• E2M - 전기 전자와 첨단 소재
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• 제8권5호
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• pp.633-639
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• 1995

Dropouts in magnetic media are a primary quality deficiency which is detrimental to magnetic signal quality and thus the major impediment to error-free recording, especially in high density digital recorders. The specific form of defects and causes found to be responsible for signal dropouts occurring in magnetic tape were studied. Dropout occurred when the RF signal falls to low level due to the various types of surface defects. However, the fall in the level of the RF signal in gravure roll coated tapes was most often caused by foreign particles adhering to the magnetic tape. It was also shown from the present study that scattered particles trapped under the tape surface or put on the top can lift it as it crosses the head, creating a spherical tent shaped defect and causing a temporary signal drop. Dropout producing substances were identified through optical and microchemical analyses. The results were correlated with measured electrical signal losses combined with analytical microscopy to clarify source identification of defects.

• 한국동물위생학회지
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• 제39권4호
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• pp.247-251
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• 2016

Salmonella is one of the most common bacteria that causes heavy losses in swine industry and major causative pathogen of food poisoning in public health. Various methods for the identification of Salmonella such as Gram staining, agglutination test, enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction (PCR) have been used. Several studies have demonstrated that Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI TOF) Mass Spectrometry (MS) identification is an efficient and inexpensive method for the rapid and routine identification of isolated bacteria. In this study, MALDI TOF MS could provide rapid, accurate identification of Salmonella spp. from swine compared with end point PCR and real time PCR.

• 한국건축시공학회지
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• 제19권5호
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• pp.467-475
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• 2019

Delay is one of the most critical issues for construction projects and leads to huge losses in both developing and industrialized countries. The construction sector in Rwanda, a rapidly-developing nation, is no exception. Delays can be mitigated only once we have identify their primary causes, and these may not be the same in each region. This study aims to ascertain the main critical factors responsible for delays in building construction in Rwanda through an intensive literature review and questionnaire survey. A total of 40 delay causative factors were obtained from a literature review and were further classified into nine major categories. The questionnaire survey was distributed to about 80 respondents from clients, contractors, and consultants. From the list of 40 different factors, the top twelve most critical causes were identified as stoppage of work due to cash flow constraints, delay in approving design documents, confidentiality of physical plan, price fluctuations and delay in approving significant change, change orders, delay in performing inspections, Ineffective project planning, inadequate drawing details, unqualified labor, lack of materials on the market and dishonesty.

• 반도체디스플레이기술학회지
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• 제21권1호
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• pp.62-66
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• 2022

Semiconductor is one of the most internationally competitive areas among domestic industries, the major concern of which is the stability of the wafer manufacturing processes. The packaging process is the final step in wafer manufacturing. Problems in the wafer packaging process cause large losses. The vibrations are supposed to be the most important factors for the packaging quality. In this study, the structure of a packaging box was analyzed through experiments and computer simulations, and further the effects of design alterations to suppress the vibrations have been investigated. The final result shows that the vibrations can be reduced substantially to improve the stability of the structure.

• 스마트미디어저널
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• 제12권1호
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• pp.54-61
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• 2023

Pricing, as one of the most important aspects of a business, should be taken seriously. Whatever affects a company's pricing system tends to affect its profits and losses as well. Currently, many manufacturing companies fix product prices manually by members of an organization's management team. However, due to the imperfect nature of humans, an extremely low or high price may be fixed, which is detrimental to the company in either case. This paper proposes the development of a fuzzy-based price expert system (Expert Fuzzy Price (EFP)) for manufacturing companies. This system will be able to recommend appropriate prices for products in manufacturing companies based on four major pricing strategic goals, namely: Product Demand, Price Skimming, Competition Price, and Target population.

• Journal of Biosystems Engineering
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• 제8권2호
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• pp.18-25
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• 1983

The binders introduced in Korea were originally designed to be used for Japonica varieties which have realtively long stem and are highly resistant to shattering. In order to use it for Tongil varieties which are short and easy to be shattered, mechanical modifications are necessary to reduce a grain loss incurred during its operation. This study was intended to investigate the binding unit, one of the major factors affecting grain losses. The binding parts of three binders used in Korea were analyzed and the grain loss was experimentally assessed for these binders. The results obtained from this study are summarized as follows: 1. From the motion analysis of discharge mechanism, the trajectory of the discharge arm appeared to be either circular or skewed elliptic. The velocity of a circular path mechanism was constant and smaller than that of a skewed elliptic path mechanism. The discharge grain loss of the former was about twice less than that of the latter. 2. It was found that the grain loss incurred due to the collision of the paddy bundles and ground was considerably high for Tongil varieties. The auxiliary discharge bar gave a significant influence on the motion and posture of the bundles, and the degree of impact on ground. 3. The installation of an auxiliary bar, which guides the paddy bundles smoothly to ground in order to reduce impact when the bundles fall down on ground, appeared to be very effective since the grain losses could be decreased by about 1.6 percentage point. However, the guide bar should be installed after some mechanical modification to reduce the velocity of discharge arm has been made.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권1호
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• pp.17-26
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• 2004

Pest monitoring through field surveys and surveillance helps in forecasting the population build up of pest. It reduces the load of pesticides application and forms the basis of Integrated Pest Management in sericulture. Common sampling techniques for quantifying pest populations and damage caused by them are reviewed emphasizing the need for quick and simple sampling methods. Various direct and indirect sampling methods for establishing pest populations are discussed and methods have been discussed to use indirect sampling method under IPM programme in sericulture. The use of pheromone lures and traps forms one of the important ingredients of integrated pest management, which calls for integration of all available methods in a cost effective and environmental friendly manner offering consistent efficacy. Silk-worms feed on the variety of silk host plants and spin cocoons. Each silk host plant is attacked in the field by number of insect pest species. Several pests are common to mulberry, tasar, oak tasar, muga and eri host plant but pest status and seasonal abundance differs from each crop. The key pests are serious perennially occurring persistent species which cause considerable yield loss every year on large areas and require control measure. Regular occurrence of minor pest is noticed but sudden increase in its population is not known. The occasional pests are sporadic but potential causing sufficient damage. Silk losses due to attack of all the pests have not been calculated. However, information on pest biology and ecology, and control practices being practiced is available but the period of outbreak of major pests and predators on silkworms and its host plant needs to be reinvestigated. Pest and predators forecasting based on surveillance information may provide an opportunity to minimize the losses, particularly to reduce expenditure involved in pest management.

• 한국통신학회논문지
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• 제24권7B호
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• pp.1322-1330
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• 1999

B-ISDN과 같은 초고속 네트워크에서 전송오류의 주요원인은 과잉밀집 상태에 있어서의 버퍼 오버플로우이며 이로 인해 셀 손실을 야기한다. 기존의 통신 프로토콜은 손실된 패킷이나 전송에러들을 다루기 위해 ARQ와 같이 오류회복을 위해 재전송 기법을 사용하고 있으나 이러한 ARQ 방법들은 재전송으로 인한 전송 지연시간이 매우 크기 때문에 초고속 네트워크에서는 적합하지 않다. 따라서 본 논문은 이러한 문제를 줄이기 위하여 B-ISDN에서 FEC를 이용한 셀손실 회복기법을 제안하였다. 제안된 기법은 새로운 순서번호(SN)인 SN*를 이용하여 연속적인 셀손실을 식별한다. SN*는 SN이외에 다른 두 개의 필드(ST, LI)를 조합하여 생성한 순서번호로 그 특성에 따라 가산적(additive) SN*와 승산적(multiplicative) SN*로 구분된다.이러한 연구결과로 FEC는 네트워크 노드상에 버퍼 오버플로우로 인한 셀손실이 발생한 경우에 유용하며 B-ISDN과 같은 초고속 통신망에서의 셀손실 회복에 효과적으로 사용할 수 있는 오류에 기법임을 보여주고 있다. 본 논문에서 제안된 효율적인 셀손실 회복기법은 향후 ATM 네트워크에서의 우선순위 제어, 과잉밀집 제어 등의 연\ulcorner에 효율적으로 사용될 수 있다.

• 자원ㆍ환경경제연구
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• 제21권4호
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• pp.947-980
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• 2012

본고는 농업부문 및 국가경제에 대한 기후변화의 장기적 영향을 분석한다. 우선 작물 시뮬레이션 및 준모수적 분석법 등을 이용하여 쌀, 낙농 및 축산업에 대한 기후변화의 생산성 영향을 예측하고, 다음으로 축차적 동태 CGE모형을 이용하여 예측된 생산성 영향으로 유발되는 경제적 영향을 평가한다. 분석결과 우선 기후변화의 생산성 영향에서, 낙농 및 축산업의 경우 지속적으로 생산성이 하락하는 것으로 예측되었고, 쌀의 경우, 작물 시뮬레이션 적용 시 생산성 하락이, 준모수적 분석법을 적용 시 생산성이 상승한 후 다시 하락하는 것으로 예측되었다. 다음으로 쌀의 두 가지 예측결과를 기준으로 두 가지 시나리오를 설정하고 축차적 동태 CGE모형에 반영하여 경제적 영향을 평가한 결과, 2050년 연간 GDP 예상손실률이 시나리오에 따라 각각 0.2%, 0.02%로 나타났으며, 세부부문별로는 농업생산부문과 식품가공업, 농업용 투입재 산업, 그리고 몇몇 유통관련 산업에서 경제적 효과가 크게 나타났다. 그리고 대부분의 선행연구에서 간과되던 낙농 및 축산업 부문의 경제에 미치는 영향이 큰 것으로 나타났는데, 위 결과는 쌀부문 외 다른 농업생산부문에서의 기후변화 효과분석이 필요함을 제시한다.

• 한국농공학회논문집
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• 제54권6호
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• pp.45-52
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• 2012

Along with global warming, ever intensifying weather events have increased damages to agricultural farms and facilities. The objective of this study was to investigate the spatial distribution and regional characteristics of agricultural damages by extreme weather events. Agricultural disaster statistics provided by the National Emergency Management Agency were summed over for a 13-year period from 1998 to 2010 and used for the spatial analysis. Two indices of damage area ration and property damage per unit area were introduced to quantify regional agricultural damages. As the results, farm inundation accounted for the largest area primarily damaged by typhoons with heavy rainfalls. Most property damages to farm lands originated from farm erosion in the alpine regions by localized guerrilla rains. The two major causes of damages to greenhouse and livestock facilities were typhoon with strong wind and winter blizzards. Gangwon was the province of the largest property loss mostly from farm land erosion losses, followed by Gyeongnam, Jeonnam, and Chungnam where losses to greenhouse and livestock facilities were relatively greater. Property loss per unit area was also the greatest for the Gangwon province (4.91 M\/ha), followed by Gyongnam and Chungnam of 2.20 and 1.50 M\/ha, respectively. Unit loss for greenhouse and livestock facilities was 13.3 M\/ha, approximately 13 times greater than that for farm land (1.06 M\/ha). The study findings indicated the importance of reducing highland farm erosion and reinforcing farming facilities structures for agricultural disaster management.