• International Journal of Fluid Machinery and Systems
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• v.10 no.1
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• pp.40-46
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• 2017

Small valves including ball valves, gate valves and butterfly valves have been adopted in the fields of steam power generation, petrochemical industry, carriers, and oil tankers. Butterfly valves have normally been applied to fields where in narrow places installing the existing valves such as gate valves and ball valves have proven difficult due to the surrounding area and the heavier of these valves. Butterfly valves are used to control the mass flow of the piping system under low pressure by rotating the circular disk installed inside. The butterfly valve is benefitted by having simpler structure in which the flow is controlled by rotating the disc circular plate along the center axis, whereas the weight of the valve is light compared to the gate valve and ball valve above-mentioned, as there is no additional bracket supporting the valve body. The manufacturing company needs to acquire the performance and life test equipment, in the case of adopting the improving factors to detect leakage and damage on the seat of the valve disc. However, small companies, which are manufacturing the industrial valves, normally sell their products without the life test, which is the reliability test and environment test, because of financial and manpower problems. Furthermore, the failure mode analysis of the products failed in the field is likewise problematic as there is no system collecting the failure data on sites for analyzing the failures of valves. The analyzing and researching process is not arranged systematically because of the financial problem. Therefore this study firstly tried to obtain information about the failure data from the sites, analyzed the failure mode based on the field data collected from the customers, and then obtained field data using measuring equipment. Secondly, we designed and manufactured the performance and life test equipment which also have the real time monitoring system with the naked eye for the butterfly valves. The concept of this equipment can also be adopted by other valves, such as the ball valve, gate valve, and various others. It can be applied to variously sized valves, ranging from 25 mm to large sized valves exceeding 3000 mm. Finally, this study carries out the life test with square wave pressure, using performance and life test equipment. The performance found out that the failures from the real time monitoring system were good. The results of this study can be expanded to the other valves like ball valves, gate valves, and control valves to find out the failure mode using the real time monitoring system for durability and performance tests.

• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.1
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• pp.56-63
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• 2016

In this study, we introduce a design of Fuzzy RBFNNs-based digit recognition system using the incremental-PCA in order to recognize the handwritten digits. The Principal Component Analysis (PCA) is a widely-adopted dimensional reduction algorithm, but it needs high computing overhead for feature extraction in case of using high dimensional images or a large amount of training data. To alleviate such problem, the incremental-PCA is proposed for the computationally efficient processing as well as the incremental learning of high dimensional data in the feature extraction stage. The architecture of Fuzzy Radial Basis Function Neural Networks (RBFNN) consists of three functional modules such as condition, conclusion, and inference part. In the condition part, the input space is partitioned with the use of fuzzy clustering realized by means of the Fuzzy C-Means (FCM) algorithm. Also, it is used instead of gaussian function to consider the characteristic of input data. In the conclusion part, connection weights are used as the extended diverse types in polynomial expression such as constant, linear, quadratic and modified quadratic. Experimental results conducted on the benchmarking MNIST handwritten digit database demonstrate the effectiveness and efficiency of the proposed digit recognition system when compared with other studies.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.4
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• pp.497-503
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• 2004

The effect of adding carbohydrate-rich feedstuffs to sweet potato leaves (SPL) on silage quality was studied using a total of 180 laboratory silos. Silage quality was assessed by changes of pH, dry matter (DM), crude protein (CP) and ammonia nitrogen ($NH_{3}$-N). Pre-wilted SPL was mixed with cassava root meal (CRM), sweet potato root meal (SPM) or sugar cane molasses (Mo) at levels of 0, 30, 60 and 90 g $kg^{-1}$ (air-dry weight of additives to pre-wilted weight of SPL). Samples for assessing silage quality were collected after mixing the SPL with the additive and thereafter at 7, 14, 28 and 56 days of ensiling. There was a marked decrease in pH after 7 days and the pH remained low and stable until day 56. Addition of 60 and 90 g $kg^{-1}$ resulted in a lower pH (p<0.05) than the other treatments. The DM content of the silage increased (p<0.05) with increasing levels of additive, while there were no differences in DM with time of ensiling. The CP content of the silage decreased (p<0.05) with increasing levels of additive. The CP content did not change up to 28 days, but was lower (p<0.05) after 56 days in all treatments. The $NH_{3}$-N levels were increasing (p<0.05) with time of ensiling, and were lower (p<0.05) with additive levels of 60 g $kg^{-1}$ or higher. Also, the additive source affected the $NH_{3}$-N values, with the lowest values found for Mo. Castrated male pigs (Large White$\times$Mongcai) were used in 4$\times$4 Latin square design to study the total tract digestibility and nitrogen (N) utilisation of diets with inclusion of ensiled SPL. The diets were based on cassava root meal with inclusion of protein from either fish meal (C) or SPL ensiled with CRM (D1), SPL ensiled with SPM (D2) and SPL ensiled with Mo (D3). The digestibility of DM, organic matter (OM) and CP were higher (p<0.05), and the digestibility of crude fibre (CF) was lower (p<0.05), in diet C than in diets D1, D2 and D3. However, there were no differences (p>0.05) in digestibility of dietary components between diets D1, D2 and D3. Also, the excretion of N in faeces was higher (p<0.05) and the N retention was lower (p<0.05) in diets D1, D2 and D3 than in diet C. It can be concluded from the present experiments, that a good quality silage can be produced from pre-wilted SPL by addition of 60 g $kg^{-1}$ of either CRM, SPM or Mo. Diets with inclusion of 450 g ensiled SPL $kg^{-1}$ DM showed a high digestibility of dietary components and thus ensiled SPL should be considered as a potential feed resource for growing pigs.

• Journal of Biomedical Engineering Research
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• v.36 no.4
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• pp.115-122
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• 2015

A standard air flow generator system was developed to generate air flows of various levels simultaneously applied to two different air flow transducer modules. Axes of two identical standard syringes for spirometer calibration were connected with each other and driven by a servo-motor. Linear displacement transducer was also connected to the syringe axis to accurately acquire the volume change signal. The user can select either sinusoidal or square waveform of volume change and manually input any volume as well as maximal flow rate levels ranging 0~3 l and 0~15 l/s, respectively. Various volume and flow levels were input to operate the system, then the volume signal was acquired followed by numerical differentiation to obtain the air flow signal. The measured volumes and maximal air flow rates were compared with the user input data. The relative errors between the user-input and the measured stroke volumes were all within 0.5%, demonstrating very accurate driving of the system. In case of the maximal flow rate, relatively large error was observed when the syringe was driven very fast within a very short time duration. However, except for these few data, most measured flow rates revealed relative errors of approximately 2%. When the measure and user-input stroke volume and maximal flow rate data were analyzed by linear regression analysis, respectively, the correlation coefficients were satisfactorily higher than 0.99 (p < 0.0001). These results demonstrate that the servo-motor controls the syringes with enough accuracy to generate standard air flows. Therefore, the present system would be very much practical for calibration process as well as performance evaluation and comparison of two different air flow transducer modules.

• Journal of the Korean Society for Nondestructive Testing
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• v.16 no.3
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• pp.162-173
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• 1996

Dry magnetic particle inspection(MPI) was performed to detect the surface defects of steel ingot cast billets. Magnetic properties of several materials were characterized by the measurement of the B-H hysteresis curve. The inspection results were evaluated in terms of the magnetizing current, temperature, and the amount of magnetic particles applied to billets. Magnetic flux leakage near the defect site of interest was measured and compared with the results of calculation by the finite element method in the case of direct magnetizing current. Direct and alternating magnetizing currents for materials were deduced by the comparison of the inspections. Results of the magnetic particle inspection by direct magnetizing current were compared with those of finite element method calculations, which were verified by measuring magnetic leakage flux above the surface and the surface defects of the material. For square rods, due to the geometrical effect, the magnetic flux density at the edges along the length of the rods was about 30% of that at the center of rod face for a sufficiently large direct magnetizing current, while it was about 70% for an alternating magnetizing current. Thus, an alternating magnetizing current generates rather uniform magnetic flux density over the rods, except for the region on the face across about 10 mm from the edge. The attraction of the magnetic particle by the magnetic leakage field was nearly independent of the surface temperature of the billets up to $150^{\circ}C$. However, the temperature should have been limited below $60^{\circ}C$ for an effective fixing of gathered magnetic particles to the billet surface using methylene chloride. We also found that the amount of applied magnetic particles tremendously affected the detection capability.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.670-676
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• 2016

In this study, we analyzed the utensils, covers and mats that were used for making meju, the shape of meju, and the heating method used for making meju from the 225 ways of preparing jang mentioned in the 32 volumes of the ancient cook books from 530 AD to 1950. The heating method of traditional meju bean and starch included 57 kinds of steaming, 59 of boiling, 21 of roasting + boiling, and 2 of cooking. The shape of meju included 41 kinds of egg, 27 of ball, 22 of lump, a kind of doughnut, 8 kinds of hilt, 6 of flat, 4 of chip, and a kind of square. Among the 72 gochoojang meju, the heating method of bean included 9 kinds of boiling, and 6 kinds of steaming; whereas the heating method of starch included 19 kinds of steaming of dough, 11 of rice cooking, and 5 of boiling of dough. The utensils for molding of bean meju were 49 kinds of straw sack, 14 of round straw container, 11 of heating bed, 7 of large straw bowl or Japanese-snailseed, 5 of jar, 4 of ditch, 3 of straw bowls, 2 of pottery steamer of dough, 2 of gourd, and a kind of long round bamboo bowl and sack of straw. The cover and the mat used for molding of meju included 36 kinds of straw, 17 kinds of paper mulberry leaf, 15 of wide straw seat, 14 of mugwort, 11 of pine tree leaf, 10 of soybean leaf, 6 of cocklebur leaf, 6 of sumac leaf, 6 of barley straw, 6 of mulberry leaf, 5 of fallen leaf, 5 of cogon grass, 4 of reed seat, 3 of scrap of cloth, 2 of Indian bean tree leaf, a kind of reed. There were only 5 kinds of hanging.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.377-377
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• 2012

Microprocessor technology now relies on copper for most of its electrical interconnections. Because of the high diffusivity of copper, Atomic layer deposition (ALD) $TaN_x$ is used as a diffusion barrier to prevent copper diffusion into the Si or $SiO_2$. Another problem with copper is that it has weak adhesion to most materials. Strong adhesion to copper is an essential characteristic for the new barrier layer because copper films prepared by electroplating peel off easily in the damascene process. Thus adhesion-enhancing layer of cobalt is placed between the $TaN_x$ and the copper. Because, cobalt has strong adhesion to the copper layer and possible seedless electro-plating of copper. Until now, metal film has generally been deposited by physical vapor deposition. However, one draw-back of this method is poor step coverage in applications of ultralarge-scale integration metallization technology. Metal organic chemical vapor deposition (MOCVD) is a good approach to address this problem. In addition, the MOCVD method has several advantages, such as conformal coverage, uniform deposition over large substrate areas and less substrate damage. For this reasons, cobalt films have been studied using MOCVD and various metal-organic precursors. In this study, we used $C_{12}H_{10}O_6(Co)_2$ (dicobalt hexacarbonyl tert-butylacetylene, CCTBA) as a cobalt precursor because of its high vapor pressure and volatility, a liquid state and its excellent thermal stability under normal conditions. Furthermore, the cobalt film was also deposited at various $H_2/NH_3$ gas ratio(1, 1:1,2,6,8) producing pure cobalt thin films with excellent conformality. Compared to MOCVD cobalt using $H_2$ gas as a reactant, the cobalt thin film deposited by MOCVD using $H_2$ with $NH_3$ showed a low roughness, a low resistivity, and a low carbon impurity. It was found that Co/$TaN_x$ film can achieve a low resistivity of $90{\mu}{\Omega}-cm$, a low root-mean-square roughness of 0.97 nm at a growth temperature of $150^{\circ}C$ and a low carbon impurity of 4~6% carbon concentration.

• Archives of Reconstructive Microsurgery
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• v.16 no.2
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• pp.113-118
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• 2007

Purpose: The purpose of this work was to describe the results of treatment for motor vehiclerelated crushing injuries among children and adolescents under sixteen years in Korea. Materials and Methods: A retrospective analysis was conducted of data from children who were under sixteen year and injured foot by motor vehicles. Cases were documented 1) age at the time of injury, 2) injured site, 3) the area of accident, 4) the kind of vehicle, 5) associated injuries, 6) methods of treatment for soft tissue reconstruction and 7) complications. The relationships between the area of accident and associated injuries, and the kind of vehicle and associated injuries were analyzed using Chi-square test and Fisher exact test. Results: There were 97 children who were 15 year and younger. The mean age was 7.4 years, and 65% were boys. The left foot was more dominant side of injury (57%). Seasonal variation was seen with the number of injuries peaking during the summer (43%, p<0.05). Among the vehicles, 78.3% were the large vehicles (bus, truck or van). The where of accident was more frequent at an alley or less than two lanes of traffic. But, the relationships between the place of accident and associated injury or the kind of vehicles and associated injury were not statistically significant. The associated injury were fracture or dislocation (23 cases, 35.9%), injury of tendon (21 cases, 32.8%). There were amputation or disarticulation of foot in 8 cases (8.2%) and post-traumatic deformities such as flatfoot, hindfoot varus or valus deformities by tendon injury in 7 cases (7.2%). Conclusion: More than 50% of crushing or degloving injuries of child's foot by traffic accidents happened in boys between 5 to 9 years old. The associated injury was unrelated with size of vehicles or accident place at the time of accident. But, even though foot injury happened in an alley or one lane by small vehicles, child who hurt feet by car need thorough investigation about associated injury. If a surgeon keep in mind and treat child to associated injury necessarily, can minimize complication. Microsurgical reconstruction for soft tissue defect was prior to other methods.

• Korean Chemical Engineering Research
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• v.55 no.6
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• pp.807-815
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• 2017

This study investigated the removal efficiency of residual pentane from paclitaxel according to the drying temperature in the case of rotary evaporation, and performed a kinetic and thermodynamic analysis of the drying process. At all the temperatures (25, 30, 35, 40, and $45^{\circ}C$), a large amount of the residual solvent was initially removed during the drying, and the drying efficiency increased when increasing the drying temperature. Five drying models (Newton, Page, modified Page, Henderson and Pabis, Geometric) were then used for the kinetic analysis, where the Henderson and Pabis model showed the highest coefficient of determination ($r^2$) and lowest root mean square deviation (RMSD), indicating that these models were the most suitable. Furthermore, in the thermodynamic analysis of the rotary evaporation, the activation energy ($E_a$) was 4.9815 kJ/mol and the standard Gibbs free energy change (${\Delta}G^0$) was negative, whereas the standard enthalpy change (${\Delta}H^0$) and standard entropy change (${\Delta}S^0$) were both positive, indicating that the drying process was spontaneous, endothermic, and irreversible.

• Korean Journal of Poultry Science
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• v.40 no.3
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• pp.223-234
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• 2013

Poultry industry is abounding day by day as it engrosses less cost of investment per bird as compared to large animals. Poultry have the most copious genomic tool box amongst domestic animals for the detection of quantitative trait loci (QTL) and marker assisted selection (MAS). Use of multiple markers and least square techniques for mapping of QTL affecting quality and production traits in poultry is in vogue. Examples of genetic tests that are available to or used in industry programs are documented and classified into causative mutations (direct markers), linked markers in population-wide linkage disequilibrium (LD) with the QTL (LD markers), and linked markers in population wide equilibrium with the QTL (LE markers). Development of genome-wide SNP assays, role of 42 K, 60 K (Illumina) and 600 K (Affymetrix$^{(R)}$ Axim$^{(R)}$) SNP chip with next generation sequencing for identification of single nucleotide polymorphism (SNP) has been documented. Hybridization based, PCR based, DNA chip and sequencing based are the major segments of DNA markers which help in conducting of MAS in poultry. Economic index-marker assisted selection (EI-MAS) provides platform for simultaneous selection for production traits while giving due weightage to their marginal economic values by calculating predicted breeding value, using information on DNA markers which are normally associated with relevant QTL. Understanding of linkage equilibrium, linkage dis-equilibrium, relation between the markers and gene of interest are quite important for success of MAS. This kind of selection is the most useful tool in enhancing disease resistance by identifying candidate genes to improve the immune response. The application of marker assisted selection in selection procedures would help in improvement of economic traits in poultry.