• Journal of Biosystems Engineering
• /
• 제20권1호
• /
• pp.13-21
• /
• 1995

This study was conducted to investigate the cutting mechanism of reciprocating knife of combine harvester. The cutting operation of reciprocating knife with the arrangement of the low-cutting and the double-cutting was demonstrated through cutting pattern diagram which was drawn by computer graphics. Various kinds and dimensions of reciprocating knives were analyzed using the developed program. The results are summarized as follows (1) The low-cutting type reciprocating knife was represented similar cutting characteristics to the standard type, but the maximum stalk-deflection was decreased as 1/2 level of the standard type. And the first ledger plate should be designed shorter than the second ledger plate. (2) The bunching area and the maximum stalk-deflection for the double cutting knife almost were not changed since cutting velocity ratio of 0.6, but the secondary cut were occurred at ratio of 0.8 and increased rapidly over these ratio. (3) The double cutting knife was recommended for the high speed combine, because its bunching area and the maximum stalk-deflection were decreased as 1/2 level of the standard type. (4) In order to maintain the proper cutting mechanism characterized by the bunching area, the maximum stalk-deflection and the secondary cutting length etc., the adequate cutting velocity at forward speed of 0.5㎧ to 1.2㎧ was from 0.3㎧ to 0.96㎧ for the double cutting knives.

• Journal of Biosystems Engineering
• /
• 제25권5호
• /
• pp.351-358
• /
• 2000

This study was conducted to develop a speed control system of a DC motor which drove a barley seeder mounted on a combine harvester. Barley seeder mounted on a combine has been known to reduce labor and cost of barley cultivation. However, development of the seeder has been unsuccessful because the combine, a dedicated rice and barley harvester has not enough space and proper power take-off for barley seeder. To develop a barley seeder, small powered motor speed controller was required. A proximity sensor for detecting working speed of the combine and a programmable one board microprocessor was used to develope a control system. Motor parameters and motor constant, relationship between seeding rate, motor speed, groove volumes of a tested roller, torque were measured. The proximity sensor sent a frequency signal to the microprocessor. In laboratory experiments, the excitation voltage of the motor was shown not to be proportional to the size of pulse width (duty ratio). A table transforming frequency signal, that represented for working speed to proper pulse width was developed from seeding rate experiments. However, seeding rate at low frequency signal was not proportional to the working speed. Seeding rate control proportional to the frequency signal was achieved by shifting of the frequency signal.

• Journal of Biosystems Engineering
• /
• 제2권1호
• /
• pp.56-80
• /
• 1977

This experimental work was conducted in order to find out the optimum time of harvest of Japonica-type (Akibare) and Indica-type(Tong-il) rice variety for three harvesting systems by investigating the harvesting losses and milling quality. The study was also concerned about the nature and amount of grain losses incurred during the each sequence of post-harvest technologies, and based on these result, a modification of existing systems giving a minimum grain loss was attempted. Binder, combine, and traditional systems were tested in this study and five grain moisture levels were disposed according to the decrease of grain moisture . The results are summarized as follows ; 1. The total losses of Akibare variety were ranged from 1.1 to 1.5 per cent for the traditional harvesting system , 2.1 to 4.8 per cent for the harvesting system by use of binder, and 2.8 to 4.3 per cent for the harvesting system by use of combine as the grain moisture content was reduced from 24 to 15 percent. Milling recovery of the harvesting system by use of binder, 74.8 ∼75.7 percent, was a little higher as it was compared to that of traditional harvesting system, 74.3 ∼75.0per cent, and that of the harvesting system by use of combine, 73.8 ∼75.0 per cent. Head rice recovery of mechanically dried paddy samples was higher than that of sun-dried paddy samples. 2. The total losses of Tong-il variety were ranged from 3.8 to 5.0 per cent for the traditional harvesting system, 5.2 to 10.0 percent for the system by use of binder, and 3.0 to 5.0 per cent for the system by use of combine as the grain moisture was reduced from 28 to 16 per cent. 3. Milling recovery of Tong-il variety harvested by the traditional harvesting system was 72.3 ∼73.6 percent and it was lower when compared to that of 72.3∼75.0 per cent harvested by binder, and 73.0∼74.6 percent harvested by combine. 4. Head rice recovery of Tong-il variety harvested by the traditional harvesting system (58.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
• /
• 제20권4호
• /
• pp.57-65
• /
• 2014

Purpose : Mental health service desire has been diversified according to the increase of economic level and rapid social change. Mental Health and Welfare Center(MHWC) is a provider of mental health services in Japan. This is a basic stage study which will suggest the architectural planning guidelines for MHWC. Methods : Data were collected through literature research, field surveys, and expert interviews to 69 MHWC in Japan. 1) Research for the policy and legal aspects of mental health support system. 2) Research for structural aspects of MHWC: Characteristics of establishment, management, and regional factors. 3) Research for the physical environment aspects of MHWC: Classification and evaluation of MHWC's Type by locational characteristics in Japan. Results : The result of this study can be summarized into three points. The first one, Mental Health and Welfare Center's service has being expanded to suicide, depression and stress from chronic mental illness, to reflect social needs. The second one, The average population of area installed at Mental Health and Welfare Center was 2,307,570 person, and average area of the regions were $5,745m^2$. The third one, Mental Health and Welfare Center is divided into single-structure type and combine-structure type. And combine-structure type is divided into medical-combine type, welfare-combine type, and public-combine type.

• Journal of Biosystems Engineering
• /
• 제16권2호
• /
• pp.124-132
• /
• 1991

This study was carried out to obtain the information needed in the development of forward speed control system and the improvement of combine performance. The effects of variety, grain moisture content and forward speed on the combine load characteristics were investigated through experiments. The results of this study are summarized as follows. 1. A data acquisition system was developed to measure the engine speed and the torques and speeds of the threshing cylinder, dean-grain auger and tailings-return auger. The system consisted of transducers, signal conditioner, interface board and microcomputer. The system accuracy is better than ${\pm}2.3%$ full scale. 2. Linear regression equations were obtained for the torque, speed and power requirement of threshing cylinder for different paddy varieties, grain moisture contents and feed rates. 3. The maximum value of relative frequency for threshing cylinder torque decreased as the increase in feed rate and moisture content. The range of torque fluctuation was 1.2~3.7 and 1.2~1.9 times the average and maximum torque, respectively. The maximum value of power spectrum density (PSD) appeared to be about 11 Hz regardless of paddy variety, grain moisture content and feed rate. 4. The speed of tailings return thrower decreased rapidly at below 900rpm, and it fell to near zero about 3 seconds after that time. When the travelling of combine harvester was stopped immediately after sensing the overload, it took about 7 seconds for a full recovery of the no-load speed of tailings return thrower.

• Journal of Biosystems Engineering
• /
• 제7권2호
• /
• pp.36-44
• /
• 1983

Farm population was rapidly decreasing due to shift of the people from farm sector to the non-farm sector caused by the economic growth of the country. Especially, a great shortage of farm labor in busy farming period in June and October is becoming a serious problem in maintaining or promoting land productivity. The peak of labor requirement in summer is caused by rice transplanting and barley harvesting. In order to reduce the restrictions imposed on farm management by the concurrence of labor requirement and the lack of labor, the experimental study for mechanization of barley harvesting has been carried out in the fields. 1. The machines for barley harvesting were knap-sack type reapers, windrow reaper (power tiller attachment), binder and combine. The order of higher efficiency of machine for barley harvesting was combine, binder, windrow reaper (WR), knapsack type reaper 1(KSTR1), and knap sack type reaper 2(KSTR2; mist and duster attachment). 2. The ratio of grain loss for the manual, binder, and combine plot was about four percent of total field yield. 3. The total yield of barley in 35 days and 40 days harvesting after heading were 514 kg and 507kg per 10 ares respectively. The yield of 35 days-plot was higher than other experimental plots. 4. The lowest yield was recorded in 30 days-plot due to the large quantity of immatured grains and having lighter 1000-grain weight. The ratio of immatured grains was 2.66 percent and 1000-grain weight was 29.4 grams. 5. The total harvesting cost of the windrow reaper was 10,178 won per 10 ares. It was the lowest value compared to other machines. The next were combine, binder, KSTR1, KSTR2, and manual in sequence. As a result, the optimum time of barley harvesting for mechanization was 35-40 days after heading. Combine, binder, and windrow reaper were recommended as the suitable machines for barley harvesting in the work efficiency. However, in total harvesting cost, the windrow reaper was the most promising machine for barley harvesting.

• Journal of Biosystems Engineering
• /
• 제38권4호
• /
• pp.248-254
• /
• 2013

Purpose: This study was performed in order to obtain basic data for policy development and R&D to sharpen competitiveness in domestic agricultural machinery industry by analyzing the recent status of demand and supply for tractor, rice transplanter(riding type), and combine. Methods: Basic data from 199,275 units of tractor, rice transplanter (riding type), and combine was offered by the National Agricultural Cooperative Federation and Korea Agricultural Machinery Industry Cooperative. Those agricultural machines were supplied by the government's loan support from 2003 to 2012. Results: Recent supply of tractor is only 13,000 units or so per annum, thereby being stagnated. Rice transplanter and combine in 2012 corresponded to 3,810 units and 2,490 units, respectively. The domestic market share of the imported agricultural machinery accounted for 60.0% in tractor, 99.5% in saddle rice transplanter, and 80.9% in combine, thereby having been sharply increased 33.1%p, 42.0%p and 53.6%p compared to the ones in 2003. Life spans of tractor, combine and saddle rice transplanter are 3.7, 3.7 and 4.2 years, respectively. Among the discontinued models, the one less than 300 units supplied was occupied up to 70~85%. Conclusions: The domestic demand and the export expansion are needed through developing a model of agricultural machinery of having competitiveness to domestically activate agricultural machinery industry.

• 한국정보통신학회논문지
• /
• 제7권1호
• /
• pp.42-49
• /
• 2003

OFDM should be used for the fourth generation communication for high speed communication. Because of high spectral efficiency and high tolerance to fading channel, OFDM is applied to many high speed wire and wireless communication such as DAB (Digital Audio Broadcast), DVB(Digital Video Broadcast), IMT 2000 etc. Inter-modulation, however, is derived from PAR(Peak to Average Power Ratio) of OFDM signals. The paper describes PTS(Partial Transmit Sequence) and SLM(Select Mapping) of an existing methods which can reduce PAR. And then this papers proposed the new method that is called "Combine method". The method proposed in this paper is to combine PTS and SLM. As a result of the simulation, Combine PAR method is better than the existing methods.

• 한국환경과학회지
• /
• 제22권2호
• /
• pp.131-138
• /
• 2013

In order to provide a scientific foundation for herb application in landscape, the photographs were taken from the herb landscape in urban green space and sightseeing garden. The questionnaire-based survey was also applied to analyze the cognitive situation of herb. Most investigators love herb, but have a low level of herb; Interviewees' consideration of herb function lie in ornamental, healthcare and medical treatment; The bulk of the visitors think herb landscape is insufficient; Investigators' preferences for herb application forms are landscape edging and combining with stone. We also probe into the optimum allocation form combining herb with landscape elements. When we combine herb with landscape water or landscape architecture, artistic conception and reasonable plant allocation should be considered; When we combine herb with landscape path or garden ornament, reasonable plant disposition and appearance and practical collocation should be thought over; When we combine herb with flower-border, richly colored landscape and reasonable plant allocation should be deliberated on.

• Journal of Biosystems Engineering
• /
• 제17권2호
• /
• pp.171-176
• /
• 1992

This study was intended to develop the design theory of the threshing unit of a head-feeding rice combine. It may be applied for various combining capacities with different cutting widths and forward speeds. Design factors in the theoretical development are : (1) dimensions of the threshing drum, (2) tooth approching angle, (3) distance between the adjacent teeth on their spiral setting line, (4) number of spirals, and (5) total number of teeth on the drum. A computer simulation program was developed to predict the proper dimensions for the threshing drum and tooth arrangement. A simulation for the prospective combine with varied capacities was also demonstrated. The parameters analyzed in the developed design theory were shown to be consistent with those of existing combines.