• JSTS:Journal of Semiconductor Technology and Science
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• 제12권3호
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• pp.341-352
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• 2012

This paper presents a Processing Engine (PE) which is used in Low Density Parity Codec (LDPC) application with a novel charge-recovery logic called pseudo-NMOS boost logic (pNBL), to achieve high-speed and low power dissipation. pNBL is a high-overdriven and low area consuming charge recovery logic, which belongs to boost logic family. Proposed Processing Engine is used in LDPC circuit to reduce operating power dissipation and increase the processing speed. To demonstrate the performance of proposed PE, a test chip is designed and fabricated with 0.18 2m CMOS technology. Simulation results indicate that proposed PE with pNBL dissipates only 1 pJ/cycle when working at the frequency of 403 MHz, which is only 36% of PE with the conventional static CMOS gates. The measurement results show that the test chip can work as high as 609 MHz with the energy dissipation of 2.1 pJ/cycle.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2002년도 춘계학술대회 논문집
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• pp.56-56
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• 2002

ERP 시스템 내에는 각 업종별로 특성에 맞는 업무 프로세스가 구현되어 있어야 함은 필수 불가결한 요소이다. 그러나, 범용 ERP 시스템은 거의 대부된 OEM 생산방식에 의존하고 있는 국내 중소 신발업체의 생산관리 방식과는 맞지 않는 부분이 너무 많다. 그러므로 신발제조회사의 현황에 맞는 ERP 시스템의 개발이 절실하다. 이를 위해서 첫째, 시스템 개발을 위한 신발생산용 업무 프로세스가 표준화되어야 하고 둘째, 프로그램 작성을 위한 표준업무 프로세스에 기초한 통합시스템 프로세스의 모형이 설계되어야 한다. 본 논문에서는 국내 신발제조업체들의 생산관리방식에 적합하고 신발생산 전용의 자원관리 시스템의 개발과 도입을 위한 기초로서 BPR의 수행과 표준 업무 프로세스를 구축하는 방법을 제안하였다. 그리고 이에 따른 신발생산 자원관리 시스템의 프로세스 모형을 제시하였다. 이 연구는 ERP 시스템 중 생산 자원계획을 위한 통합 프로세스 모형의 구축에 초점이 맞추어져 있으며 통합 프로세스 모형은 13개 모듈로 구성되었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.493-497
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• 1991

A problem of analysis and design of asymptotically reliable serial production systems, closed with respect to the number of carriers that transport parts between operations, is addressed. A case study of a paint shop operation at a modern automobile assembly plant is described. The results obtained indicate that optimization of the system with respect to the number of carriers available and the capacity of the feedback buffer leads to a substantial improvement in the production rate.

• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1123-1128
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• 1999

Sheep meat is the most expensive meat in developed countries. Consumption is dependent on cultural factors and will increase as population and incomes grow. In the main exporting countries (New Zealand and Australia), sheep numbers are decreasing as the market for wool is declining. Sheep meat production will develop in small and medium scale commercial systems, close to their markets.

• 한국유기농업학회지
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• 제25권4호
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• pp.805-819
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• 2017

The study was carried out to develop a mathematical model for evaluating the effect of organic fertilizers in organic rice production systems. A function to simulate the nitrogen mineralization process in the paddy soil has been developed and integrated into ORYZA2000 crop growth model. Inorganic nitrogen in the soil was estimated by single exponential models, given temperature and C:N ratio of organic amendments. Data collected from the two-year field experiment were used to evaluate the performance of the model. The revised version of ORYZA2000 provided reasonable estimates of key variables for nitrogen dynamics and crop growth in the organic rice production systems. Coefficient of determination between the measured value and simulated value were 0.6613, 0.8938, and 0.8092, respectively for soil inorganic nitrogen, total dry matter production, and rice yield. This means that the model could be used to quantify nitrogen supplying capacity of organic fertilizers relative to chemical fertilizer. Nitrogen dynamics and rice growth simulated by the model would be useful information to make decision for organic fertilization in organic rice production systems.

• Asian-Australasian Journal of Animal Sciences
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• 제17권1호
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• pp.18-26
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• 2004

This study evaluated the impact of an AI heifer calf rearing scheme on dairy stock development, in a coconut grazing and a peri-urban smallholder dairy production system in the Western Province of Sri Lanka. The heifer rearing scheme included free advice on calf rearing, drugs, acaricides, minerals and subsidised concentrates for 30 months. The farmers in the coconut growing area integrate dairying with their plantation, they sell their milk to the main processors. The peri-urban farmers are intensive milk producers, who sell their milk at informal markets. To estimate the effect of the heifer rearing scheme on dairy replacement stock development, scheme farmers were compared with farmers who did not participate in the scheme. Calf mortality was twice as high in non-scheme farms (23-28%) as in scheme farms (12-14%). The scheme had a positive effect on weight development and scheme heifers calved 4.5 months earlier than non-scheme heifers. The calf rearing package is cost effective in both farming systems, however, the required cash inputs are a major constraint. The costs per in-calf heifer under the scheme are much lower than the production of such animals by either multiplication in state farms or importing them. The coconut grazing system showed the highest potential for producing surplus dairy stock.

• Asian-Australasian Journal of Animal Sciences
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• 제14권5호
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• pp.733-745
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• 2001

This review paper discusses the relevance and potential importance of food-feed systems in Asian agricultural systems, and in particular the role and contribution of legumes to these systems. A food-feed system is one that maintains, if not increases, the yield of food crops, sustains soil fertility, and provides dietary nutrients for animals. It involves a cropping pattern within which the feed crop has many beneficial effects without competing for land, soil nutrients and water with the food crops. The agricultural environment is described with reference to the priority agro-ecological zones and prevailing mixed farming systems in Asia. Within these systems, animal production is severely hampered by critical feed shortages which can however, be alleviated by the integration of suitable leguminous forages into the cropping systems. The review also focuses on the role and potential importance of leguminous forages in terms of biodiversity, their uses in farming systems, beneficial effects on animal performance, and draws attention to six case studies in different countries that clearly demonstrate many benefits of developing such food-feed systems. Considerable opportunities exist for widening the use of forage legumes in the development of systems with several complementary advantages (e.g. fenceline, cover crops, fodder banks, forage source and erosion control) to improve the development of sustainable crop-animal systems in Asia.

• Asian-Australasian Journal of Animal Sciences
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• 제22권2호
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• pp.216-224
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• 2009

In Japan, since rice consumption has been decreasing with the westernization of Japanese eating habits, surplus paddy fields have been increasing. If these surplus paddy fields can be utilized for forage rice production as feed for animal production and excretions (feces and urine) from animal production can be applied to the paddy fields as manure, then the problems of surplus paddy fields and excretions from animal production may be solved, and the environment kept sustainable. The objectives of the present study were to apply a bio-economic model to dairy and forage rice integration systems in Japan and to examine the merit of introducing whole crop rice silage (WCRS), as well as economic and environmental effects of various economic and management options in the systems. Five simulations were conducted using this model. The use of WCRS as a home-grown feed increased environmental loads and decreased economic benefit because of the higher amount of purchased feed, when compared to the use of typical crops such as maize, alfalfa and timothy silage (simulation 1). Higher economic benefits from higher forage rice yields and higher milk production of a dairy cow were obtained (simulations 2, 3). There were no economic and environmental incentives for utilizing crude protein (CP) rich WCRS, because an increase in the CP content in WCRS led to the use of more chemical fertilizers, resulting in high production costs and nitrogen outputs (simulation 4). When evaluated under the situation of a fixed herd size, increasing forage rice yields decreased the total benefit of the production, in spite of the fact that the amount of subsidies per unit of land increased (simulation 5). It was indicated that excess subsidy support may not promote yield of forage rice. It was, however, observed in most cases that dairy and forage rice integration systems could not be economically established without subsidies.

• IEIE Transactions on Smart Processing and Computing
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• 제5권1호
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• pp.22-28
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• 2016

Multi-loop control of a boost converter needs a current-sensing circuit to detect the inductor current. Current sensorless multi-loop control reduces the cost, size and weight of the converter. The Luenberger observer (LO) is widely used to estimate the inductor current for current sensorless control of a switching converter. However, the design of the LO-based sensorless multi-loop control has not been well presented, so far. In this paper, a closed-loop characteristics evaluation method is proposed to design an LO-based current sensorless multi-loop control for boost converters. Simulations show evaluations of the closed-loop characteristics. Practical experiments on a digital processor confirm the simulations.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1118-1122
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• 2005

In order to keep production balance at a mixed-model assembly line and a painting line, large WIP(Work- In-Process) inventories are required between two lines. To increase the efficiency of line handling through reducing the inventories under this circumstance, this paper concerns with a sequencing problem for a mixed-model assembly line that includes a painting line where the uncertain elements regarding the defective products exist. Then, we formulate a new type of the sequencing problem minimizing the line stoppage time and the idle time with forecasting the supply time of the products from the painting line. Finally, we examine the effectiveness of the proposed sequencing through computer simulations.