• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.479-485
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• 2002

본 연구는 초음파를 이용하여 한우도체의 연도를 비파괴적이며 객관적으로 측정할 수 있는 시스템을 개발하기 위해서 수행되었다. 한우도체 연도 측정 시스템은 크게 초음파 측정장치, 자동 탐촉자 수직이동장치, 데이터 획득 및 분석장치로 구성되었는데 초음파 측정장치는 초음파 pulser/receiver 및 탐촉자, 자동 탐촉자 이동장치는 상하운동부, 구동부, 제어부, 데이터 획득 및 분석장치는 digitizer, Labview 5.1을 사용하여 구성되었다. 통합된 시스템을 이용하여 획득된 도체의 초음파 신호를 분석하기 위해 1.0~1.1 MHz의 bandpass filtering을 거쳐 hilbert 변환을 이용, envelope를 구할 수 있었으며 탐촉자와 도체의 최적 접촉 위치를 결정하기 위하여 3단계로 나누어 신호분석을 실시하였다. 시료의 개수는 40개였으며 획득된 envelope를 FFT 변환 후 PLS, PCR 분석을 수행한 결과 7단계의 PCR 분석에서 $R^2$= 0.6474의 유의성 있는 결과를 나타내었으므로 최적 접촉 위치로 결정하였다. 최적 접촉 위치를 통해 시료 80개의 추가 실험을 실시한 결과 PCR 분석에서 $R^2$= 0.4304의 결과를 나타내었으며 이를 이용, 도체의 연도를 측정하는 프로그램을 개발하고 최종 통합 시스템을 구축하였다. 본 한우도체 연도 측정 시스템의 개발을 통해 한우도체의 전단력을 예측하여 연도를 객관적으로 판정 가능할 것으로 생각되며 또한 사이즈의 확대로 도축장에 설치하는 설비로서 가능할 것이라 사료된다. 그러나 추후 좀 더 세밀한 측정과 결과의 보완을 위한 분석방법의 개선에 관한 연구가 진행되어야 할 것이다. 사용해 설계된 장치를 사용자가 쉽게 제작할 수 있도록 하였다. 공정설계프로그램을 통해 설계된 공정은 데이터베이스에 저장이 되며 장치설계프로그램에서 쉽게 이전에 설계했던 공정을 이용할 수 있도록 하여 공정 설계와 장치설계를 연계하도록 하였다.동투하시간과 비용 -종자준비부터 통마늘선별까지의 일관기계화로 투입된 주요작업의 노력은 75∼76%가 절감되고, 재배규모 3ha기준시 비용은 44-53%절감되었음. the annealing texture. Observations by TEM and EBSD revealed the formation of very fine grains of ∼1.0$\mu\textrm{m}$ after CCSS.he dislocations form local defect arrangements at the grooves permitting the substantial reduction in defect density over the remainder of the interfacial area.한 최대의 감자 재배지역을 형성하였다. 제주도는 산지지형과 따뜻한 기온으로 2기작이 가능하고, 감자가공 공장설립과 교통발달에 따른 육지 시장과의 접근이 용이해졌기 때문에 남한에서 2번째로 큰 감자재배지역이 되었다.(요약 및 결론에서 발췌)그람양성균에서 효과적이었으며, 농도별 항균력시험 결과 농도가 증가할수록 비례하여 저해율도 증가함을 알 수 있었다. 첨가농도를 달리하여 미생물의 생육도를 측정한 결과, fraction II磎꼭\ulcorner경우 그람양성균에 대해 500 ppm 이상에서 뚜렷한 증식억제효과를 나타내었다.서 뚜렷한 증식억제효과를 나타내었다.min/+}$계

• Journal of Conservation Science
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• v.37 no.2
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• pp.167-178
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• 2021

For the preservation and efficient content sharing of 5 volumes (2,866 pages) of Yu Kil-Chun's book published in 1971, which provides an important collection of data for the study of modern Korean history during the late 19th century (enlightenment period of Joseon dynasty). The books were purchased and its preservation status investigated and documented electronically by scanning for permanent preservation of content and to determine the condition of preservation at the time of documentation. The degree of deterioration and damage, such as discoloration, hardening, breakage, and damage in these 50 years old modern printed books was quantified through image analysis and made attempts to visualize the damaged areas. It was observed that the degree of deterioration and damage depended on the material and the surface condition of the paper used, the degree of exposure to light, and the storage environment. The comparison of the preservation status at the time of the photographing (or scanning) and judgment as to whether or not the image under investigation was artificially modified was accomplished by comparing the electronically documented images of Seoyugyeonmun (西遊見聞) in Volume 1 of Yu Kil-Chun's works with images provided on other websites. Practical problems encountered while considering the effective preservation of electronically documented data and publicly sharing it, in the course of this study, with other academic researchers around the world were also summarized.

• Journal of Biosystems Engineering
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• v.3 no.1
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• pp.33-46
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• 1978

To get the goal of self-supply of food grain, improvement of post-harvest grain operations in rural area is under consideration as an important task of agriculture in Korea. This is study is focused on elimination of losses and deteriorations of grain and reduction of labour requirements and funds for post-harvest grain operations. The purpose of this study are presentation of basic data referring to conventional post-harvest grain operations in rural area and suggestion of improving methods for the operations, and also finding out reasonable operating processes of the operations. The result of this study are follows; 1. Grain drying in-the-filed which is performed before threshing has major factors of grain loss during drying, and so should be restrained as possible. Combine harvesting system is recommended among other king of mechanized harvesting systems for restraining in-the-field drying and securing available labors for drying. 2. It is predicted that mechanical grain drying could be prevalent when combine harvesting is taken place. Recommended grain drier for pre-combine harvesting system and for combine harvesting system is batch-type drier and circulating -type drier, respectively. 3. As existing farm storages for grain have insufficient spaces and offer poor conditions for grain storing , it is greatly needed to build up new storage which store only grains. And it is concluded that storing grain in community common storages in desirable. 4. Power supplying system for milling machinery in local milling plants, that a large capacity prime mover supplies power to 4 to 6 kinds of milling machinery simultaeously, should be converted to a system of several small capacity prime movers supplying power to each machiner y for the purpose of reducing extra consumption of energy. 5. Governmental grain, of which Korean farms produced, should be milled and stored in the local milling plant successively for the purpose of reducing transportation fee and stroing facilities. 6. Furture post-havest grain operations-drying, storing and milling should be periormed successively in he community common plant. And average optimum processing capacity of the plant is estimated about 300 metric ton of grain every year.

• Journal of the Korean Institute of Gas
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• v.15 no.3
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• pp.67-73
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• 2011

One of the important topics to prepare the up-coming era of so-called ‘hydrogen economy’ is hydrogen transmission. Pipeline is conceivably the most economic way to consistently and safely transport a large amount of hydrogen over a long distance, which may be strongly requested in hydrogen economy era. As a good starting point for the purpose, one might wonder whether conventional API pipeline steels as designed for natural gas transmission can be used as the hydrogen pipeline materials or not. To answer the question, here we performed a series of micro-/nano-indentations together with tensile tests on the hydrogen-charged API X65, X70 and X100 steels having different strength level. In this paper, from the results of tensile tests, the hydrogen effects on the mechanical behavior in the API steels are systematically evaluated.

• Journal of IKEEE
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• v.22 no.2
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• pp.289-301
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• 2018

IIoT, the IoT technology applied to the industrial field, is being used as a monitoring technology for increasing in production rate and safety of workers. However, monitoring through the construction of IIoT network using Ethernet and RS485 in production lines where dozens to hundreds of machine tools are manufacturing components, have difficulties of infrastructure cost and network flexibility and fluidity. Therefore, in this paper, using IEEE 802.15.4 standard WSN device to construct a Ad-Hoc WSN in the production line. In addition, the transmission period and order of the sensor nodes are set by applying the EtherCAT communication method in which the payload frames are shared by all the sensor nodes. From this, we have overcome the problem of reliability decline and real-time issue due to the packet collision of wireless network and confirmed that it is a wireless network routing method that can be used in the actual industrial field.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.42-47
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• 2017

In this study,we conducted an injection molding analysis of metal powder materials for the development of flanges, which are necessary adapters for optical communication. The metal powder injection molding process is a technique for producing an injection molded article having a complicated shape by mixing ceramic or stainless powder and binders. It is used to produce products which require complex processing technology or for which the productivity is low. The purpose of this study is to minimize the manufacturing processing of products which are manufactured through existing mechanical processing procedures. For the injection molding analysis, we mixed stainless STS316 metal powder with binders at a ratio of 6 to 4 to make molding materials consisting of granular pellets. Then, three-dimensional modeling and meshing were carried out to obtain the optimal injection molding analysis conditions(molding temperature, melting temperature, injection time, injection temperature, injection pressure, packing time and cooling time). As a result of the analysis, it was discovered that the inlet became available 13.29 seconds after the first injection. Also, as the flowing and packing in the melt through the sprue, runner and gate were stable, it is expected that good molds can be manufactured.

• Korean Journal of Agricultural Science
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• v.11 no.2
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• pp.278-283
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• 1984

Shearing characteristics of cornstalks were investigated under quasi-static conditions at various knife approach angles and shear angles in order to determine their importance to the cutting action of mowers. Corn variety used in this study was pioneer that was grown in the field of Chungnam National University. The results obtained were as follows: 1. The shearing process had two shearing stages in cornstalks, which was different from those of rice and other forage crops due to the hard crust. 2. Force and energy of shear were decreased progresively with height of the cornstalks. 3. The minimum shear force occured at shear angle of about $60^{\circ}$ and approach angle of about $10^{\circ}$ 4. The condition of minimum shear energy coincides with that of minimum shear force. 5. Effects of knife approach angles were more significant than those of shear angle for force and energy of shear.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.12a
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• pp.72-72
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• 2020

곤달비(Ligularia stenocephala)는 쌍떡잎식물, 국화과의 다년생 초본식물로서 한국·일본·타이완·중국 등에 분포하며, 우리나라에는 전남 홍도가 특산 자생지라고 하며 주로 강원도, 경북 경주, 전북 남원 등지에서 재배되고 있다. 곤달비는 어린 부분을 생채, 데친 나물, 국거리, 튀김, 묵나물로 식용한다. 특수 성분으로는 Isopropenyl, dimethoxybenzofuran, Liguhodgsonal, Ligujapon, Ligularinone A, Ligularinone B 등이며 신경을 안정시키는 진정작용, 진통억제, 정기를 보익하고 허약함을 보하는 기능이 있고, 한방에서는 뿌리가 신경통, 유종(乳腫) 등에 쓰인다. 곤달비는 주로 시설하우스나 노동력이 많이 드는 임간에서 재배되어 생산 단가가 높아 소비활성화를 위한 가공제품을 생산하기가 힘들다. 본 연구는 곤달비를 저비용 대량 생산을 위한 노지재배 생력화 재배기술을 확립하고자 시험을 수행하였다. 2019년 4월부터 2020년 11월까지 전라북도 농업기술원 허브산채시험장(해발 500m)에서 곤달비 노지재배를 대상으로 이랑폭 90cm, 120cm, 180cm 3처리구로 하여 시기별 생육특성, 수량성, 생리장해 등을 조사하였다. 2019년 4월 정식 후 활착률은 180cm 처리구에서 92.1%로 가장 높았고 120cm 처리에서 90.2%로 가장 낮았으며, 생존율 또한 180cm 처리구에서 87.2%로 가장 높았고 120cm 처리에서 84.4%로 가장 낮았다. 생육특성 결과 1차년도에는 초장, 엽장, 엽폭은 생육 초기부터 후기까지 90cm 처리구에서 가장 높았고, 엽수는 120cm 처리구에서 가장 많았다. 2차년에는 180cm 처리구에서 초장 61.2cm, 엽장 32.6cm, 엽폭 31.3cm, 엽수 12.7개/주로 다른 처리구에 비해 좋은 생육상태를 보였다. 이랑폭별 수확량은 180cm에서 1,073.7kg/10a로 120cm 955.7kg/10a, 90cm 923.3/kg/10a 비해 높은 수량성을 보였다. 생리장해는 2020년 3월 저온으로 인한 냉해를 출현 초기에 모든 처리구에서 받았다. 곤달비 노지재배 발생하는 병해충은 나비·나방류, 노린재류 3종류이며 그 중 점무늬병은 모든 처리구에서 30% 이상 피해가 나타났다.

• Journal of Preventive Medicine and Public Health
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• v.15 no.1
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• pp.187-196
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• 1982

The followings are the results of the study on industrial accidents occurred at 12 factories manufacturing metal products during the period of 2 years from January 1980 to December 1981 in the area of Yong-Dung-Po in Seoul. The results of the study are as follows: 1. The incidence rate of industrial injuries was 45.7 per 1,000 workers of the sample group and the rate of male (54.0) was three times higher than that of female (17.5). 2. In age groups, the highest rate was observed in the group of under 19 years old with 83.5, while the lowest in the group of 40s. 3. It was found that those who had short term of work experience produced a higher rate of injuries, particularly, the group of workers with less than 1 year of experience showed the highest rate of it as 48.1%. 4. In working time, the highest incidence rate occurred 3 and 7 hours after the beginning of their working showing the rate of 6.0 and 6.1 per 1,000 workers, respectively. 5. The highest incidence rate was observed on Monday as 8.4 per 1,000 workers, and it was 18.3% in aspect of the days of a week. 6. In aspect of the months of a year, the highest incidence was observed on July 1,000 workers and the next was on March as 4.8. These figures account for 11.8% of total occurrence in respective month. as 5. 4 per and 10.5% 7. In causes of injuries, the accident caused by power driven machinery showed the highest rate with 37.5%, the second was due to handling without machinery with 17.2%, and the third was due to falling objects with 14.2%, and striking against objects with 10.2%, and so on. 8. By parts of the body affected, the most injuries 84.3% of them occurred on both upper and lower extremities with the rate of 58.8% for the former and 25.5% for the latter. Fingers were most frequently injured with a rate of 40.3%. Comparing the sites of extremities affected, rate of injuries on the right side was 55.0% and 45.0% on the left side. 9. In the nature of injury, laceration and open wound were the highest with 34. 0%, the next was fracture and dislocation with 31. 9%, and sprain was the third with 8.1%. 10. On the duration of treatment, it lasted less than one month in 68.9% of the injured cases, of which 14.5% of the cases were recovered within 2 weeks, and 54.4% of them were treated more than 2 weeks. And the duration of the treatment tended to be prolonged in larger industries. 11. The ratio of insured accidents to uninsured accidents was 1 to 4.7.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.305-315
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• 2016

Due to the change from small volume production to small quantity batch production systems, individual companies have been attempting to produce a wide range of operating strategies, maximize their productivity, and minimize their WIP level by operating with the proper cycle time to defend their market share. In particular, using a complex workflow and process sequence in the manufacturing line has some drawbacks when it comes to designing the production strategy by applying analytical models, such as mathematical models and queueing theory. For this purpose, this paper uses three heuristic algorithms to solve the job release problem at the bottleneck workstation, product mix problem in multi-purpose machine(s), and batch size and sequence in batch machine(s). To verify the effectiveness of the proposed methods, a simulation analysis was performed. The experimental results demonstrated that the combined application of the proposed methods showed positive effects on the reduction of the cycle time and WIP level, and improvement of the throughput.