한국농업기계학회:학술대회논문집 (Proceedings of the Korean Society for Agricultural Machinery Conference) (Proceedings of the Korean Society for Agricultural Machinery Conference)
한국농업기계학회 (Korean Society for Agricultural Machinery)
- 반년간
과학기술표준분류
- 농림수산식품 > 농업기계/설비
- 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
- 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
- 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.I
- 한국농업기계학회 2000년도 하계 학술대회 논문집
- 한국농업기계학회 2000년도 동계 학술대회 논문집
한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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The torque loads were measured at the input shaft of the transmission and driving shaft of the tractor having a cage wheel attached to the driving tires as a traction aid during. a rotavating operation in wet paddy fields with deep hardpan. Their load spectra were also calculated. Effects of design parameters of the cage wheel on the load characteristics were analyzed. The torque load exerted on the input shaft decreased as diameter of the cage wheel increased and increased as the rotating speed of the rotavator increased. The torque load exerted on the driving shaft increased as the working speed of the tractor increased and decreased as the PTO speed increased. Both the torque loads with the cage wheel were greater than those without the cage wheel. The cage wheel was developed for this study.
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The objective of this study is to measure rim surface adhesion and to calculate motion resistance produced by the adhesion acting on the rim section of a circular wheel under sticky soil condition. The mechanisms of generating motion resistance by the adhesion on a circular wheel were analyzed through wheel motion. Experiments were conducted in an indoor soil bin that contains loam soil. A circular steel wheel was used for experiments. A part of the wheel rim was cut off, and transducers which can measure normal and tangential forces were installed in this section. Calculated motion resistance at a part of the rim section was superposed for one wheel rotation as motion resistance produced by the rim surface adhesion. The motion resistance increased with increasing the dynamic load. Ratio of the motion resistance to total motion resistance measured by an axis transducer was about 23 to 46 % in this study.
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Using the modified DEM (Discrete Element Method), which we proposed in order to improve the accuracy of the simulation, soil behavior and reaction by lugs of rotating wheel and a soil cutting process by a high speed blade were calculated and compared with experimental data. The DEM is one of computational mechanics, where the object body is supposed as an assembly of small particles called elements and not a continuum as in the case of FEM. We can easily treat some discrete phenomena such as cracking, separating and sliding by the DEM. We had to modify the original mechanical model, which induced too free movement of elements, adding a tension spring, which would display the role of soil adhesion. The results of DEM simulations were successful from both the soil behavior and reaction points of view.
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In this study, the NEURAL NETWORK (hereinafter referred to as NN) was applied to control of the nonlinear factors for turning movement of the crawler vehicle and experiment was carried out using a small model of crawler vehicle in order to inspect an application of NN. Furthermore, CHAOS NEURAL NETWORK (hereinafter referred to as CNN) was also applied to this control so as to compare with conventional NN. CNN is especially effective for plane in many variables with local minimum which conventional NN is apt to fall into, and it is relatively useful to nonlinear factors. Experiment of turning on the slope of crawler vehicle was performed in order to estimate an adaptability of nonlinear problems by NN and CNN. The inclination angles of the road surface which the vehicles travel on, were respectively 4deg, 8deg, 12deg. These field conditions were selected by the object for changing nonlinear magnitude in turning phenomenon of vehicle. Learning of NN and CNN was carried out by referring to positioning data obtained from measurement at every 15deg in turning. After learning, the sampling data at every 15deg were interpolated based on the constructed learning system of NN and CNN. Learning and simulation programs of NN and CNN were made by C language ("Association of research for algorithm of calculating machine (1992)"). As a result, conventional NN and CNN were available for interpolation of sampling data. Moreover, when nonlinear intensity is not so large under the field condition of small slope, interpolation performance of CNN was a little not so better than NN. However, when nonlinear intensity is large under the field condition of large slope, interpolation performance of CNN was relatively better than NN.
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Complex gear shifting and high speed-reduction ratio reduce the transmission efficiency in power driveline of agricultural tractors. According to a field test, the power transmission efficiency of a tractor in transporting operations was estimated about 70%. However, the actual efficiency was found by the experiment to fluctuate in a range of 56 to 87%. Therefore, the constant efficiency model commonly used for a simulation of power drivelines is not likely to simulate its performance more accurately. In order to predict power transmission efficiency more accurately, a new model was proposed and the new concepts of the maximum efficiency and sticking torque were introduced. The error mean between the measured and the predicted efficiencies was about 2.3% in mean. The new model reflecting the transmission characteristics in the power driveline of tractors could be used to analyze and predict the power transmission performance of tractors more accurately.
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The mechanism of the inner resistance in a rubber crawler system has been investigated to reduce the power requirement (Kitano et al. 1994). The rolling resistance of the track roller, which is one of the major inner resistances, was measured for seven different vertical loads. The rolling resistance changed periodically and could be classified into three types. In case of the vertical load less than 500N, the rolling resistance was almost constant. For the vertical load greater than 500N, the maximum value of the rolling resistance increased. Further more in case of the vertical load greater than 1200N, negative resistance appeared. Analytical simulation of the travel resistance based on experimental results and static equilibrium equations derived from three-dimension mechanical model for the rubber crawler system. It was found that the simulation method was carried out to evaluate the travel resistance occurred by the rolling resistance of the track roller. The rolling resistance for each track roller arrangement and effects of the lug phase in the right and left rubber crawler could be estimated quantitatively.
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Inoue, Eiji;Konya, Hideyuki;Hirai, Yasumaru;Noguchi, Ryozo;Hashiguchi, Koichi;Choe, Jung-Seob 146
The rubber crawler system for farm machine is composed of driving units such as track rollers, driving sprockets and rubber crawlers. Vibration characteristics of the rubber crawler system varies by driving speed, center of gravity, mass□moment of inertial□location arrangement of track rollers and dynamic parameters such as dynamic spring constant (k) and viscous damping coefficient (c) of a rubber crawler. In general, vibration of the rubber crawler system occurs by reason for mechanical interaction between the rubber crawler and track rollers. Because the dynamic spring constant and viscous damping coefficient vary periodically by mechanical characteristics(deformation characteristics) of the rubber crawler when track rollers drive on the between lugs of the rubber crawler. Therefore, both dynamic parameters k and c were expressed as Fourier series by authors through the shaking test of the rubber crawler and further, vibration characteristics of the rubber crawler system could be simulated analytically. However, actual values of dynamic parameters k and c are different from those obtained by the shaking test because dynamic characteristics of the rubber crawler vary by the effect of variable tension and driving resistance of track rollers. So, actual values of k and c should be identified in the condition of actual driving test. In this study, dynamic parameters such as k and c of the rubber crawler system, which are expressed as Fourier series, were identified using the Gauss-Newton Method. Therefore, validity of identified parameters k and c was discussed through the simulation using experimental data of actual driving test. As a result, in the Fourier series of dynamic parameters of spring constant k and viscous damping coefficient c, excellent parameter convergence and simulation were observed using the Fourier series' zero order and first term of the dynamic model. Furthermore, it was clarified that identification for model parameters which are fitted to actual dynamic motion (vibration) wave of the crawler system was possible by using the time series data observed in vertical and pitching motion of the crawler system. -
A series of soil bin experiment was carried to investigate the effects of rotary blade shape, rotational direction of rotary blade, number of blade and soil cutting disk blade on the characteristics of partial tillage. Among the three types of rotary blades, rotary blade for cultivator was considered to be proper for partial tillage of direct seeder considering the torque requirements and ratio of soil breaking. There is no need to attach so many blades to the rotary shaft. Four rotary blades were enough for efficient partial tillage by rotary tiller. Though soil cutting disk blade assisted the better formation of seedbed furrow, attachment of the soil cutting disk blade increased torque requirements.
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This study was carried out to develop a continuously variable-speed transmission(CVT) for agricultural tractor. A full-toroidal CVT mechanism with four discs and six rollers was selected as a device for changing speed ratio continuously. In the step of system layout design, the sizes of roller cylinders and end-load cylinder, which were critical factors for controlling the variator, were designed. Also the control pressure range was designed to limit the contact pressure of variator. In order to make the maximum speed of vehicle as 30km/h, the planetary gear and the six pairs of gears were designed. Also the hydraulic clutch, silent chain, hydraulic manifold and electronic controller were designed. After the design, a prototype with CVT controller was developed and tested. The speed of vehicle was changed continuously to the speed set by driver and the settling time was about 0.52 second at the step-response test (reduction ratio of variator 2.0 to 1.0), which was acceptable as a response time for working with tractor.
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Sorting cut roses according to quality is very essential to increase the value of the product. Many factors are involved in determining the grade of cut roses: length, thickness, and straightness of stem, color and maturity of bud, and extra. Among these factors, the stem straightness and bud maturity are considered to be difficult to set proper classification criteria. In this study, a prototype machine and an analysis procedure were developed to grade cut roses according to stem straightness and bud maturity by utilizing color image processing and neural network. The test results indicated 15.8% classification error for stem straightness and 10.0% for bud maturity.
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The tillage operation by rotary implements is widely done in Korea. In the case of rotary implements, the tillage depth control system is one of important implement control systems. A contact type-sensor for measurement of the ground height was designed and fabricated to evaluate the possibility of application of the sensor on the tillage depth control system. Indoor experiments were conducted to obtain static and dynamic detection characteristics of the sensor under various conditions; 1) several moisture contents for four soil samples, 2) two soil surfaces with a designed configuration, 3) four heights of the sensor from the soil surface, 4) five traveling speeds of the carrier on which the sensor was attached, and so on. The experimental results showed the detection characteristics of the sensor sufficient as the ground height sensor of the tillage depth control system.
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This study was conducted to measure the moisture content of powdered food using RF impedance spectroscopic method. In frequency range of 1.0 to 30㎒, the impedance such as reactance and resistance of parallel plate type sample holder filled with wheat flour and red-pepper powder of which moisture content range were 5.93∼-17.07%w.b. and 10.87 ∼ 27.36%w.b., respectively, was characterized using by Q-meter (HP4342). The reactance was a better parameter than the resistance in estimating the moisture density defined as product of moisture content and bulk density which was used to eliminate the effect of bulk density on RF spectral data in this study. Multivariate data analyses such as principal component regression, partial least square regression and multiple linear regression were performed to develop one calibration model having moisture density and reactance spectral data as parameters for determination of moisture content of both wheat flour and red-pepper powder. The best regression model was one by the multiple linear regression model. Its performance for unknown data of powdered food was showed that the bias, standard error of prediction and determination coefficient are 0.179% moisture content, 1.679% moisture content and 0.8849, respectively.
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On the assumption that the voices of the cows are produced by the linear prediction filter, we characterized the cows' voices. The order of this filter is determined by examining the voices characteristics both in time and frequency domains. The proposed order of the linear prediction filter is 15 for modeling voice production of the cow. The combination of the two parameters of the fundamental frequency, the slope of the straight line regressed from the log-log spectra of the amplitude-envelope and the only one coefficient involved in the linear prediction filter can differentiate the two cows.
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At harvest, the starch contents of apples, which were related to their maturity, were quantified by using image analysis. The stained area was measured by a computer vision system when an apple slice was stained with KI/I
$_2$ solution. The stained area ratio of the stained area of the apple slice to its whole area, or the starch index, was defined as an indicator of starch content. When Tsugaru apples were manually sorted into immature, turning and mature groups, their starch indices were 0.374, 0.312 and 0.129, respectively. Meanwhile, the starch index had correlation to various physicochemical properties of Tsugaru apples. At the statistically significant level of 0.1 %, it was correlated with the pH value, bio-yield force, rupture force and color of intact and skin-removed apples. At the 1 % significant level, it had the correlation with the density and moisture content. -
Since the SSC(soluble solid contents) and titratable acidity of fruit are highly concerned to the taste, the need for measuring them by non-destructive technology such as NIR(Visual and Near-infrared) spectroscopy is increasing. Specially, in order to grade the quality of each fruit with a sorter at sorting and packing facilities, technologies for online measurement satisfying the tolerance in terms of accuracy and speed should be developed. Many researches have been done to develop devices to measure the internal qualities of fruit such as SSC, titratable acidity, firmness, etc. with the VIS(Visual)/NIR(Near Infrared) reflectance spectra. The distributions of the SSC, titratable acidity, firmness, etc. are different with respect to the position and depth of fruit, and generally the VIS/NIR light can interact with fruit in a few millimeters of pathlength, and it is very difficult to measure the qualities of inner flesh of fruit. Therefore, to measure the average concentrations of each quality factor such as SSC and titratable acidity with the reflectance-type NIR devices, the spectra of fruit at several positions should be measured. Recently, the interest about the transmittance-type VIS/NIR devices is increasing. NIR light can penetrate through the fruit about 1/10-1/1,000,000 %. Therefore, very intensive light source and very sensitive sensor should be adopted to measure the transmitted light spectra of intact fruit. The ultimate purpose of this study was to develop a device to measure the transmitted light spectra of intact fruit such as apple, pear, peach, etc. With the transmittance-type VIS/NIR device, the feasibility of measurement of the SSC and titratable acidity in intact fruit cultivated in Korea was tested. The results are summarized as follows; A simple measurement device which can measure the transmitted light spectra of intact fruit was constructed with sample holder, two 500W-tungsten halogen lamps, a real-time spectrometer having a very sensitive CCD array sensor and optical fiber probe. With the device, it was possible to measure the transmitted light spectra of intact fruit such as apple, pear and peach. Main factors affecting the intensity of transmitted light spectra were the size of sample, the radiation intensity of light source and the integration time of the detector. Sample holder should be designed so that direct light leakage to the probe could be protected. Preprocessing method to the raw spectrum data significantly influenced the performance of the nondestructive measurement of SSC and titratable acidity of intact fruit. Representative results of PLS models in predicting the SSC of peach were SEP of 0.558 Brix% and R2 of 0.819, and those in predicting titratable acidity were SEP of 0.056% and R2 of 0.655.
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The study was executed for development of sensing elements of electronic tongue which could discriminate taste of liquid and semi-liquid foods. Five polymeric membranes which were composed of polymer, plasticizer, electro-active materials were prepared. After each polymeric membranes were mounted in an electrode body, membrane potentials due to electrochemical reaction with taste stimuli were measured. The experimental results were interpreted in view of the membrane's non-selective responses to stimuli.
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Agricultural products are easily deformable its shape because of some external forces. However, these force behavior is difficult to measure quantitatively. Until now, many researches on the mechanical property was performed with various methods such as material testing, chemical analysis and non-destructive methods. In order to investigate force behavior on the cellular unit of agricultural products, electro-microscope based 3D image processing method will contribute to analysis of plant cells behavior. Before image measurement of plant cells, plant sample was cut off cross-sectioned area in a size of almost 300-400
${\mu}$ m units using the micron thickness device, and some of preprocessing procedure was performed with fixing and dyeing. However, the wall structure of plant cell is closely neighbor each other, it is necessary to separate its boundary pixel. Therefore, image merging and shrinking algorithm was adopted to avoid disconnection. After then, boundary pixel was traced through thinning algorithm. Each image from the electro-microscope has a information of x,y position and its height along the z axis cross sectioned image plane. 3D image was constructed using the continuous image combination. Major feature was acquired from a fault image and measured area, thickness of cell wall, shape and unit cell volume. The shape of plant cell was consist of multiple facet shape. Through this measured information, it is possible to construct for structure shape of unit plant cell. This micro unit image processing techniques will contribute to the filed of agricultural mechanical property and will use to construct unit cell model of each agricultural products and information of boundary will use for finite element analysis on unit cell image. -
The feasibility of precision farming for small sized fields was studied by determining fertilizing amount of nitrogenous and calcareous to a cite specific region. A detailed soil survey at three experimental fields of 672㎡, 300㎡ and 140㎡ revealed a considerable spatial variation of the pH and organic matter(OM) levels. Soil organic matter was measured using Walkley-Black method and soil pH was measured with a pH sensor. Soil sample was obtained by Grid Node Sampling Method. The soil sampling depth was 10 - 20 cm from the soil surface. To display soil nutrient variation, a soil map was made using Geographic Information System (GIS) software. In soil mapping, soil data between nodes was interpolated using Inverse Distance Weighting (IDW) method. The variation was about 1 - 1.8 in pH value and 1.4 -7 % in OM content. Fertilizing Amount of nitrogenous and calcareous was determined by the fertilizing equation which was proposed by National Institute of Agricultural Science and Technology.(NIAST). The variation of fertilizing amount was about 3 - 11 kg/10a in nitrogenous and 70 - 140 kg/10a in calcareous. The results showed a feasibility of precision fertilizing for small size fields.
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The optimal equations to predict the soil tempratures of twelve cities in the region of the southern part of the Korea such as Changhung, Cheju, Chinju, Kwangju, Masan, Miryang, Mokpo, Muan, Pusan, Sogwipo, Ulsan, Yoosu, were suggested as function of time and soil depth and the time dependent variation and soil depth dependent distribution of temperature were analyzed for the back data of the geothermal energy utilization system design and agricultural usages. The equation form is
$T(x,\;t)\;=\;T_{m}\;-\;T_{so}{\cdot}Exp(-\xi){\cdot}cos{\omega}(t\;-\;t_{o}\;-\;x\;/\sqrt{2{\alpha}{\omega}}$ ) and it can predict the soil temperatures well with the correlation factor of 0.98 or upwards for most data. The range of mean soil temperature was$14.99~18.53^{\circ}C$ and soil surface temperature swing, 11.65~14.54 days, soil thermal diffusivity,$0.025~0.069\;m^2/day$ except Mokpo of$0.100\;m^2/day$ , and phase shift, 19.66~27.81 days. During about thirty years from 1960s to 1990s, the mean soil temperature was increased by$0.04~1.25^{\circ}C$ . The temperature difference depending on soil depth was not significant. -
Soil chemical properties, relief of field surface, SPAD values and grain yield were investigated in a 0.5ha paddy field in 1999 to obtain basic field information for precision agriculture. Descriptive statistics of field information showed that the coefficient of variation ranged from 1.63% to 38.7%. Field information showed a high spatial dependence for within paddy field. The ranges of spatial dependence were from 15m to 60m, respectively. Kriged maps enable the visualization and comparison the spatial variability of field information. The causes of spatial variability of the field information could be explained rationally by a field management map. Grain yield was negatively correlated with pH, relief values, whereas, was positively correlated with total C, total N, C/N ratio, mineralizable N, available P and exchangeable K, Ca at the significant level of 1 %.
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One of the way of the preserving environment is the circulation of materials. Japan's cereal food self-sufficiency rate is less than 30%. Japan imports more than 30 million tons of food every year. Japanese are afraid of international food trade giving damages to environment. Advanced farm mechanization integrated with precision farming is an answer to solve these problems. Crop scientists, soil scientists and agricultural engineers at Kyoto University cooperate together in studying precision agriculture for paddy rice since 1996. Automatic follow-up combine and autonomous vehicle have been developed. Remotely sensing by using machine vision has been studied to measure nitrogen contents. Field map i.e. soil, growth and yield, in paddy field of 0.5 ha has been made. In this report the concept and objectives of advanced farm mechanization and precision agriculture research at Kyoto University are introduced.
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A machine vision system using charge coupled device(CCD) camera for the weed detection in a radish farm was developed. Shape features were analyzed with the binary images obtained from color images of radish and weeds. Aspect, Elongation and PTB were selected as significant variables for discriminant models using the STEPDISC option. The selected variables were used in the DISCRIM procedure to compute a discriminant function for classifying images into one of the two classes. Using discriminant analysis, the successful recognition rate was 92% for radish and 98% for weeds. To recognize radish and weeds more effectively than the discriminant analysis, an artificial neural network(ANN) was used. The developed ANN model distinguished the radish from the weeds with 100%. The performance of ANNs was improved to prevent overfitting and to generalize well using a regularization method. The successful recognition rate in the farms was 93.3% for radish and 93.8% for weeds. As a whole, the machine vision system using CCD camera with the artificial neural network was useful to detect weeds in the radish farms.
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The objective of this research is to detect the papaya fruits on tree in an orchard. The detection of papaya on natural background is difficult because colors of fruits and background such as leaves are similarly green. We cannot separate it from leaves by color information. Therefore, this research will use shape information instead. First, we detect an interested object by detecting its boundary using edge detection technique. However, the edge detection will detect every objects boundary in the image. Therefore, shape description technique will be used to describe which one is the interested object boundary. The good shape description should be invariant in scaling, rotating, and translating. The successful concept is to use Fourier series, which is called "Fourier Descriptors". Elliptic Fourier Descriptors can completely represent any shape, which is selected to describe the shape of papaya. From the edge detection image, it takes a long time to match every boundary directly. The pre-processing task will reduce non-papaya edge to speed up matching time. The deformable template is used to optimize the matching. Then, clustering the similar shapes by the distance between each centroid, papaya can be completely detected from the background.
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Hirai, Yasumaru;Inoue, Eiji;Hashiguchi, Koichi;Kim, Young-Keun;Inaba, Shigeki;Tashiro, Katsumi 287
Calculation of the flexural rigidity value (EI) is indispensable for prescription of deflection characteristics of crop stalks in harvesting□Conventionally□EI has been determined by either average EI of the whole stalk or average EI of each stems divided into node through the calculation method of cantilever with homogeneous section□However□deflection characteristics of crop stalks caused by mechanical operation such as combine harvester were not exactly presumed by these conventional EI through the experiment by authors. Further, actual EI of a stalk changes in company with a change of moisture contents as time passes during the experiment. Finally, efficient calculation method for determining EI is needed in order to improve these problems. In this study, mechanical model based on actual structure of the crop stalk with variety sectional area was proposed. This mechanical model is calculated by the theory of cantilever with continuous stages. Therefore, improvement of both calculating accuracy on EI and efficiency of measuring system was tried. At first, this calculation method was applied to piano wire of which EI was recognized in advance. As a result, EI calculated from this new method coincided approximately with piano wire's EI. Next, applying to crop stalks as same as piano wire, relationship between loads acting on crop stalks and deflection values calculated by EI using this new calculation method was exactly presumed in comparison with conventional method. Further, measuring time of deflection test was greatly reduced. Finally, new calculation method of EI will be available for estimating mechanical characteristics of so many kinds of crop stalks in harvesting operation. Further, in this study, new deflection test using image-processing apparatus by computer will be introduced. -
We have developed bio-system derived algorithm: Leaf Cellular Automata(LCA). LCA are one form of cellular automata. LCA are reffered to activity of a leaf. LCA have four layers: the "CO
$_2$ Layer", the "Stoma Layer", the "Starch Layer" and the "Water Layer". In order to evaluate this optimization algorithm, we used a pattern matching problem. -
This paper introduces a new concept of automation for bio-production with tele-operative system. The proposed system showed practical and feasible way of automation for the volatile bio-production process. Based on the proposition, recognition of the job environment with object identification was performed using computer vision system. A man-machine interactive hybrid decision-making, which utilized a concept of tele-operation was proposed to overcome limitations of the capability of computer in image processing and feature extraction from the complex environment image. Identifying watermelons from the outdoor scene of the cultivation field was selected to realize the proposed concept. Identifying watermelon from the camera image of the outdoor cultivation field is very difficult because of the ambiguity among stems, leaves, shades, and especially fruits covered partly by leaves or stems. The analog signal of the outdoor image was captured and transmitted wireless to the host computer by R.F module. The localized window was formed from the outdoor image by pointing to the touch screen. And then a sequence of algorithms to identify the location and size of the watermelon was performed with the local window image. The effect of the light reflectance of fruits, stems, ground, and leaves were also investigated.
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This study was carried out to develop an automatic grafting system suitable for fruit-vegetable seedlings. The study consisted of two research sections: 1) development of a medium-sized, low-cost automatic grafting system for cooperative farms and commercial seedlings production company, and 2) commercializing research for prototype development based on the above concepts. The grafting robot developed in this research can be described as follows, a. Developed grafting robot can cover the whole operations for grafting scion and rootstock, only if operator provides scion and rootstock tray. b. Five seedlings can be grafted at one time, and about 1,200 seedlings can be grafted in one hour. c. The success ratio of mechanical grafting scion and rootstock with ceramic pin bonding provided by the holder is more than 95% when the conditions of seedlings are satisfied. d. The grafting efficiency has improved over 10 times compared with manual work, and the grafting cost generated 44% savings.
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In this research, a grafting robot with plug in method is used. Plug in method is a method that uses a tapered axis for scion and a tapered hole for stock as processing style of conjugation parts. In the case of handling a grafting seedling, gripping a stem is doing with simple mechanisms of devising to reduce damages to stems. For example, providing cushions between gripper and stem, and fitting a gripper to a stem. Both scions and stocks need cutting, but there is bigger influence for scions than stocks, so problems of cutting scions and special qualities of grippers are necessary to investigate.
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Ultrasonic and magnetic resonance imaging systems are used to visualize the interior states of biological objects. These nondestructive methods have many advantages but too much expensive. And they do not give exact color information and may miss some details. If it is allowed to destruct some biological objects to get the interior and exterior information, constructing 3D image from the series of the sliced sectional images gives more useful information with relatively low cost. In this paper, PC based automatic 3D model generator was developed. The system was composed of three modules. One is the object handling and image acquisition module, which feeds and slices objects sequentially and maintains the paraffin cool to be in solid state and captures the sectional image consecutively. The second is the system control and interface module, which controls actuators for feeding, slicing, and image capturing. And the last is the image processing and visualization module, which processes a series of acquired sectional images and generates 3D graphic model. The handling module was composed of the gripper, which grasps and feeds the object and the cutting device, which cuts the object by moving cutting edge forward and backward. Sliced sectional images were acquired and saved in the form of bitmap file. The 3D model was generated to obtain the volumetric information using these 2D sectional image files after being segmented from the background paraffin. Once 3-D model was constructed on the computer, user could manipulate it with various transformation methods such as translation, rotation, scaling including arbitrary sectional view.
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The objective of this research work is to develop an autonomous levee-weeding robot. In this paper, pathway control system for the robot is developed and simulated. A prototype autonomous vehicle for levee weeding is also developed and used in the actual test. The results obtained in this research work is summarized as follows; 1) The simulated typical time history of lateral displacements and heading angle of the vehicle in straight run shows that the vehicle tendency is always to achieve the target path from any of its deviated position and heading angle. 2) The test run on an asphalt surface by the prototype crawler-type vehicle is in good agreement with the simulation results.
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An automatic guidance system for combine was designed to harvest paddy rice by following a predetermined path. The automatic guidance system consisted of DGPS to locate position of combine, a gyro sensor system to measure heading angle, ultrasonic sensors to detect obstacles, a hydraulic system, microcomputer as a controller, and I/O interface system. Hydraulic cylinders and valves were installed to control movement of the combine. The heading angle and the position of the combine, and ultrasonic measurements from edge were used as the inputs of the controller. The operating position of hydraulic cylinder was determined as output of the controller. The automatic guidance system was evaluated at the 45-m straight path by changing the posture of the combine. The average RMS errors were 14.0 cm without offset and 15.0 cm with 1-m offset. The DGPS provided accurate position information within the limited error to guide the combine in the field. The results showed that the automatic guidance system could guide the combine autonomously in the paddy field when the posture of the combine was changed.
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Recent mechatronics technology is the most appropriate high technology in the agricultural application to save repetitious labor. Cow's body parameters were measured by traditional several measurer. Image processing technology was used to measure automatically their parameters to reduce lots of labor and time. The parameters were measured form a small model cow, which is easily measured, instead to a real cow. The image processing system designed and built for this project was composed of a Pentium PC, and TV frame card two cameras which were located on side and top of model cow. 11 parameters of cow's body were measured and the error between real data and the data by image processing was less than 10%. Based on the results of this research the parameters of a real cow could be measured in the future.
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In Korea, researches on year-round leaf vegetables production system are in progress, most of them focused on environmental control. Therefore, automation technologies for harvesting, transporting, and grading are in great demand. A robot system for harvesting lettuces, composed of a 3-DOF (degree of freedom) manipulator, an end-effector, a lettuce feeding conveyor, an air blower, a machine vision system, six photoelectric sensors, and a fuzzy logic controller, was developed. A fuzzy logic control was applied to determine appropriate grip force on lettuce. Leaf area index and height were used as input variables and voltage as an output variable for the fuzzy logic controller. Success rate of the lettuce harvesting was 94.12%, and average harvesting time was approximately 5 seconds per lettuce.
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A survey on the rice processing facilities scattered in the country was conducted in order to collect some basic data for the facilities upgrading and renovation plans. Thirty RPC and 287 custom rice mills were randomly selected among 30 cities and counties in eight provinces where the present status of facilities, management practices and other matters were monitored and evaluated. Following are the major findings of this survey.
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The red ginseng is very popular as a health food. It has been manufactured with raw ginseng by the conventional method. But, the yield of the heaven grade ginseng (the best quality red ginseng) among the whole products is around 5-7%, Therefore, the yield should be improved in order to increase economic returns. In this study, a new model of drying system was developed to improve the yield of heaven grade ginseng from 7% to 15% or more. For this system, temperature and relative humidity were controlled by the feedback control system, and a solenoid valve for steam supply and other variables were controlled by the PC. The special features of this system developed are an image processing system for monitoring the red ginseng during the drying process in the drying chamber, and a cylindrical porous tray for holding ginseng that is rotating with the speed of 0-10rpm in the drying chamber and makes uniform drying of red ginseng possible.
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A rice mill plant with a capacity of 2.5 ton/hr was constructed with automated facilities at Chonnam National University. A simulation model was developed with SLAM SYSTEM for evaluating and improving the rice mill plant. The developed model was validated in the views of hulling efficiency, milling efficiency, milled rice recovery, other materials produced, and bottlenecks in the processes. The results of hulling efficiency, milling efficiency, milled rice recovery in the simulation were, respectively, 81.1%, 89.5%, and 73.1%, while those of the actual mill plant were 81.5%, 90.2%, and 73.5%. The simulation results including the productivity of other materials(chaff, bran, broken rice, stone, etc) produced in the processes were almost similar with those of the actual process. In the simulation the bottlenecks were found out in the processes of separating brown rice and of sorting colored rice. These phenomenon also appeared in the actual process. It needed to increase the hourly capacity of the brown rice separator and the rice color sorter. As the developed model could well express the automated rice mill plant, it could be used for designing and improving rice mill plants. In addition, an alternative model needed to be developed for the system control more accurately and for increasing the rice quality.
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This study was performed to examine the effects of infrared (IR)/heated-air combination drying on some quality attributes of Korean white ginsengs. Ginseng roots were dried in a dryer where both the far infrared ray and heated-air are available as drying energy sources. Diametral shrinkage, external color, total saponin content, and ginsenosides and free sugar composition of the IR/heated-air combination dried ginsengs were measured and compared with those of commercial white ginseng products. The external color became lower in lightness and higher in saturation as the IR radiating plate temperature increased. IR/heated-air combination dried white ginsengs at IR plate temperature of 100
$^{\circ}C$ was comparable to the commercial white ginseng products in color characteristics. Diametral shrinkage ratios ranged from 20 to 36% and appeared to be independent on the different drying methods. No definite evidence could be found whether the IR/heated-air combination drying and the conventional. hot-air drying practice resulted in white ginsengs having different ginsenoside contents and compositions. No conclusion could be made on whether the various drying treatments used in the study had effects on the free sugar contents and compositions of white ginsengs. -
Post harvest processes for rice include drying, storage and processing. Drying has a great effect on the quality of the grain. The existing rice centers are with the ill equipped, especially with drying and storage facilities. The rice harvesting has bully mechanized, a large volume of rice with high moisture content are taken to the rice processing complex(RPC). Three, the need for drying and storage facilities becomes more urgent. At present the daily drying capacity of RPC can't exceed over 40~50 M/T. Therefore new technology and facilities for a high quality and main efficient drying should be introduced one such technology is the continuous flow drying system. This research, aims to test performance efficiency the mixed continuous flow grain dryer was whose daily drying capacity is 100 M/T. The results of the performance tests of the dryer are shown as follows; (1) The temperature distribution of the drying modules were measured by a temperature recorder. The fifth module showed the highest value, followed by the seventh and the third. (2) When the intake air temperature was
$55^{circ}C$ , the drying rates were 1.7 and 2.6%, wb/pass in the exhaust temperatures of 20 and$22^{circ}C$ . And when the intake air temperature was$60^{circ}C$ , the drying rates were 1.7 and 2.3%, wb/pass in the exhaust temperatures of 22 and$25^{circ}C$ . (3) The average increased rate of cracked grains after the drying process was 0.7% which is below the tolerance limit (2.0%) of the continuous grain dryer. -
A natural air in-bin grain dryer with a grain circulator was developed for on farm use. Natural air drying test for rough rice was carried out to evaluate drying rate, uniformity of moisture content distribution in grain bed and energy consumption. It took 10 days to dry 8 ton of paddy rice from 21.9%(w.b) to 16.7%(w.b) moisture contents using the prototype dryer. The average drying rate was 0.52%/day. The uniformity of moisture content after drying was superior to the conventional natural air dryer where is grains were not circulated during drying periods. The dryer performance evaluation index was 738.3KJ/(kg.water), which was more effective than that of grain circulation t)pe hot air dryer(3,500-5,000 KJ/kg.water).
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Samples of banana were dried in a two-stage heat pump dryer capable of producing stepwise control of the inlet drying air temperature while keeping absolute humidity constant. Two stepwise air temperature profiles were tested. The incremental temperature step change in temperature of the drying air about the mean air temperature of 30
$^{\circ}C$ was 5$^{\circ}C$ . The total drying time for each temperature-time profile was about 300 minutes. The drying kinetics and color change of the products dried under these stepwise variation of the inlet air temperature were measured and compared with constant air temperature drying. The stepwise air temperature variation was found to yield better quality product in terms of color of the dried product. Further, it was found that by employing a step-down temperature profile, it was possible to reduce the drying time to reach the desired moisture content. -
The water conditioning experiments of brown rice were performed to verify the effect of brown rice conditioner and to decide the optimum operating variables for the conditioner. The initial moisture contents of 13-14%(wb) brown rice were used as experimental samples. The flow rate of brown rice passing through the conditioner was 2,940 kg/hr and water was supplied proportionally from 80 cc/min to 240 cc/min. The differences between expected and measured moisture contents were neglected except 0.25%(wb) of the maximum differences at 0.2920((cc/min)-water/(kg/min)'%-brown rice) of water supply rate. For the initial moisture contents of 13-14%(wb) brown rice, it was found that a proper water supply rate was 0.2415((cc/min)-water/(kg/min).%-brown rice) and the increments of whole rice was 2.3% compared to non conditioned ones. It was considered that the conditioning process did not influence the whiteness of milled rice because the whiteness differences between conditioned and non-conditioned milled rice were negligible.
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Fertilizer impaction mechanism was simulated using a commercial program RecurDyn
$^{(R)}$ a dynamic program that could handle contact problems. Even if there had been numerous papers on modeling of fertilizer applicator, the performance predictions were not satisfactory due to simplification in modeling. The most significant simplification was assumption of fertilizer particles as a solid particle. The assumption would eliminate rotation of fertilizer particles during the impaction mechanism. However, impaction of rotating body would be different from that of a solid particle. This paper introduced how the impaction was modeled using RecurDyn$^{(R)}$ . In order to simulate, restitution coefficient and contact time was measured. A stiffness coefficient and a damping coefficient of a fertilizer was theoretically estimated using the measured data. Validity of the simulation result was not proved yet, but judged to be promising.ged to be promising.ing. -
Positioning garlic cloves in upright standing in garlic field has been regarded as a very important job because it affects clove rooting, growing and, eventually, quality and yield in garlic production, Because of the geometrical uniqueness and irregularity of garlic cloves in shape, the planting operation has been conducted by manual work that needs a tremendous human labors and increases garlic production cost. The overall objective of this research was to develop garlic planting machine through investigating physical properties of garlic and designing clove upright positioning device after figuring out the factors affecting metering device and upright clove positioning mechanism. With the outcomes of the metering and posture positioning experiment, a garlic clove planter having twelve planting rows was developed for 37kW type tractor and feasibility test was carried out in the field. And, According to the performance test and cost analysis, the planter could accomplish planting operation of one hectare plot in 6.3 hours giving 48 times better efficiency, 6.3hrs/ha, and 74.2% of production cost reduction effect, 1,092,546won/ha, than the manual works of 299hrs/ha and 282,258won/ha. And, break-even point ofthe planter was calculated as of 2.71 hectares.
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This study was carried out in order to find out an effective machinery utilization strategy by conducting a survey on utilization and maintenance of agricultural machinery. The survey showed that the no. of utilization hours for power tiller in a year was 190.2hrs, 208.6hrs for tractor, 59.1hrs for rice transplanter, 74.0 hrs for combine, 44.6 cultivator and 254.4hrs for 4.4hrs for grain dryer. The period covered the time the machine was until it became unserviceable. The results are as follows: 10.0yrs for power tiller, 7.5yrs for tractor, 7.4yrs for rice transplanter and 5.4yrs for combine. This indicate that the actual period of use for power tiller and rice transplanter was longer than the expected period of duration years so there is a need for adjustment. The factors considered by the farmers for purchasing agricultural machine were: farm size(32%), machine operation (26.0%), performance(l4.0%) and post or after sales service(12.6%), according to the survey. It showed that repair cost rate in a year was classified into major agricultural machine; 4.8% for combine; 3.9% for tractor; 3.5% for rice transplanter; 2.0% for power tiller; 1.6% for grain dryer; and 1.2% for cultivator. The reasons for poor maintenance were insufficient after sales service(25%) and difficulty in buying parts(75%) because of the unavailability of parts in local shops(55%), imported models(30%) and outmoded model(15%).
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The Higher industerialization, The shorter labor for fanning with not also reduction of quantity like as agricultural population but also deterioration of quality like as old age or womon in Korea. Most of Farmers magnified their farm land for increasing income, but they have been in difficulties because of employment of skillful driver of farm machinery and ensurance farm labor which need finishing seasonable works. (omitted)
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A persimmon harvesting vehicle that can be operated in hilly orchards as well as a manipulator that can be used to harvest persimmons located in remote positions in the trees were designed and developed. The vehicle could be operated with keeping balanced position in an inclined field and its working platform could be moved up and down easy to approach fruits in a remote region with the aids of a hydraulic and a electrical and electronics systems. The weight of the vehicle was 927 kg and the center of gravity was located at 427 mm to the inner side from the center of a right driving caterpillar, 607 mm to a rear axle from the center of a front axle, and 562 mm to upward from ground. The automatic level control sensor for leveling the working platform was activated within 14.5 ∼ 16.5 degrees of slope variation. The total length of the manipulator was 1.39 m and weight is 975 g. It was powered by a 12 V geared motor to detach persimmon fruits with a rotational force. The gripper was made of plastic and rubber to increase a frictional force. In a performance evaluation test, static tipping angle, dynamic tipping angle toward front side when the vehicle was moving downward, climbing angle, driving speed of the vehicle were measured or calculated. In persimmon harvesting tests 24.9% of yield was increased by hand picking with the aid of the vehicle and additional 7% of yield were increased when the manipulator was used. Therefore, 99010 of total possible yield was achievable when both of the vehicle and the manipulator were used for the manual persimmon harvesting. Increase in 22.5% of total yield was achieved with the manipulator only.
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Cabbage is the most important vegetables in korea. The cabbage production was based on arduous human labor. A comprehensive research for substituting the human work by machines has been performed at present. In general, cabbage is cultivated on hillside in korea. The harvested cabbage in a field and carrying it to a vehicle for transportation are very laborious work. Hand labor in cabbage transportation to the market damages the quality of cabbage and is also a cause to increase the cost of cabbage production. This study was to design and evaluate a prototype cabbage loader for deserving efficient and safe transportation of cabbage. The developed cabbage loader was a semi-tracked vehicle operated by a hydraulic system, allowing the safe transporting and the loading of cabbage in a steep field. The maximum loading capacity of the loader was 1.0 ton. By using safety devices attached to the loader, the static slopes were 34.0% and 37.4% for the left and the rear roll-over, respectively. The maximum field speed was about 6km/hr with two cabbage pallets of 750kg at a 25% inclined field. The field capacity was about 35 pallets/hr in case of picking up, carrying and unloading two cabbage pallets. The field efficiency of the loader was analyzed to be more than 8 times in comparison of the conventional human labor. The developed loader would be applied for loading and carrying the other vegetables due to the similarity of operations. The study suggested a standard approach to the design of field machines operated in a steep field.
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Since Chinese cabbages weigh 3 to 5kgf and are big in size at the time of harvest, handling operations such as harvesting, loading and unloading including transportation require the highest labor demand among all other cultivation processes. Recently, though several cabbage harvesters were developed in Japan and Europe, those harvesters were not suitable for Chinese cabbages cultivated in Korea because of the size and shape. The cabbage harvester is almost meaningless without any proper cabbage piling and pallet unloading mechanism. Most harvesters developed so far adopted a sort of slide and free falling way in collecting cabbages into the pallet. Three or four labors are usually required for cleaning incoming cabbages and loading those in the pallet. Because of the required time for piling cabbages without severe damage and the required space capacity to carry empty and loaded pallets, harvesting speed should be adjusted in accordance with time required for consecutive operations. Up to now, any automatic or semi-automatic collecting device has not been developed in the world to pile cabbages on the layer one by one into the pallet in the ordered way with little damage and to unload pallet from the harvester continuously during the harvest process. To compromise system expenses and function, Semi-automatic cabbage piling and pallet unloading mechanism was devised and it required one labor. The foldable mesh pallet with a size of 1050mm x 1050mm x 1000mm and holding capacity of around 70 cabbages was utilized. The prototype for piling and unloading mechanism was composed of three parts such as feeding device, automatic piling device with retractable bellows, and pallet unloading device. Prior to developing the prototype, the geometric properties and the amount of the damage of the cabbage caused during the piling operation were investigated. Considering the height of the pallet, a series of cabbage carrying plates were mounted to the bracket chain to lift and to carry cabbages to the loading device. Indoor laboratory experiments showed that the cabbage carrying chain conveyor worked successfully. Considering the conveying speed 0.46m/sec of the pull up belt from the cabbages on the ground, the speed of cabbage carrying chain conveyor worked property in the range of 0.26m/sec to 0.36m/sec. The system allowed the operator to modify the position of cabbage slightly. Overall system worked successfully resulting into almost same capacity without severe damage to the cabbage as human did.
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Performance of a hydraulic system is influenced by its working temperature. Therefore, it is very important to make the system perform uniformly in an entire range of the working temperature. In this study a simulation of a hydraulic control system for the powershift transmission of tractors was conducted and the effect of the temperature was investigated in terms of design conditions of the system. Results of the simulation are as follows. The hydraulic control system with a spring accumulator was found to be more convenient to control the shifting time than that with a gas accumulator. By returning the oil from the clutches to the system through a path between the filter and pump, the time delay due to the pressure difference between the low and high temperatures could be reduced. Therefore, it was recommended that the hydraulic control system for the powershift transmission of tractors must be equipped with a spring accumulator and a circuit to return oil from the clutches to the system through a path between the filter and pump.
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Performance of a four- wheel tractor fabricated by Tongyang Moolsan Co., Ltd, Korea was tested in Thailand during May-June 2000. Wheel slip and field capacity were measured in three fields using different traction devices and implements. The tractor worked satisfactorily in the test conditions. Wheel slip of 26.05-33.63 % and the field capacity of 0.17 - 0.20 ha/hr were observed during plowing operation. Further tractive performance tests using a three-point linkage configuration are recommended in Thailand field conditions. Different designs of cage wheels are recommended to be tested to optimize the tractive performance.