• Journal of Advanced Marine Engineering and Technology
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• 제9권1호
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• pp.74-88
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• 1985

The wear becomes the most complicated cause of making various machineries short lives. In the studies by many scholors so far, the accurate and perfect methods to eliminate it completely are not found yet owing to many affected factors. On this view point of Depositional Wear, the wear test with seven different specimens from the part of frequent usage of which are carbon steel, nickel, copper, aluminum, zinc, lead and tin was attempted to make clear the relation between the wear of different metals and their melting point, crystal structure, sliding speed, load and lattice factors. The results of this study are summerized as follows; 1) Worn amount of each metal is maximum when each metal is same quality. 2) The easier becomes the the formation of solid solution in the course of friction proceeding, the more it results in worn amount of each metal. 3) The samer is each metal in crystal structure as well as lattice factor, the more it results in worn amount of each metal. These results might be of use in designing machineries, selecting materials and operating machineries.

• 한국세라믹학회지
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• 제43권2호
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• pp.131-135
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• 2006

In this study, the dielectric, magnetic and transport properties of $Gd_{0.33}Sr_{0.67}FeO_3$ have been analyzed. The dielectric loss anomaly was found to be around 170 K. The activation energy corresponding to relaxation process of this dielectric anomaly was 0.17 eV. From the temperature dependence of the characteristic frequency, we concluded that the elementary process of the dielectric relaxation peak observed is correlated with polaron hopping between $Fe^{3+}\;and\;Fe^{4+}$ ions. The electrical resistivity displayed thermally activated temperature dependence above 200 K with an activation energy of 0.16 eV. In addition, the temperature dependence of thermoelectric power and resistivity suggests that the charge carrier responsible for conduction is strongly localized.

• 한국세라믹학회지
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• 제42권9호
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• pp.613-617
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• 2005

We present the results of a combined magnetization, dc and magneto-transport study of the n = 2 Ruddlesden-Popper compound $Ca_3Mn_2O_7$ The negative thermoelectric powder is observed. The magnetic measurement data show that there is sharp magnetic transition at 134 K. However, the de and magnetoresistance of $Ca_3Mn_2O_7$ show no particular transport. Transport properties of the compound $Ca_3Mn_2O_7$ are interpreted in terms of activated hopping of small polarons in non-adiabatic regime. Polarons are most probably formed around $Mn^{3+}$ sites created by oxygen sub-stoichiometry.

• 농촌계획
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• 제16권3호
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• pp.67-76
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• 2010

The objective of this study is to investigate a priority and selection of agricultural specialization items from Daegu and Gyeongbuk region by using analytical tools such as, the Analytic Hierarchy Process(AHP) and the Scoring Method. The results of this study are as follows; 1) Five major items were selected for each region based on Daegu and Gyeongbuk regional agricultural performances. 2) The results of AHP analysis, Daegu and Gyeongbuk's agricultural experts evaluated the weight of three decision-elements(objectiveness 0.35, efficiency 0.341, identity 0.309) and seven decision-elements. 3) Results of AHP and Scoring Method analysis, Investigated a priority of agricultural specialization 3 items in 25 cities and districts Daegu and Gyeongbuk regional agricultural performances. 4) Finally, The results of this study will provide basic information on agricultural specialization policy in Daegu and Gyeongbuk region.

• Current Research on Agriculture and Life Sciences
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• 제29권
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• pp.63-74
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• 2011

The purpose of this study is a classification of farm typology and an analysis of characteristic e-commerce type of farm enterprises. The classification of sample farm enterprises thus results in six distinctively agribusiness type. The six identified types can be characteristic as follows: production type, processing type and distribution type, e-commerce type, export-agricultural type, amenity-tourism type. This article attempted to come up with workable strategies to solve these problems affecting e-commerce type farm enterprises. The main results this paper are as follows: 1) to make organization of e-commerce type farm enterprises to accomplish business goals 2) to find out solution for urgent problems and subjects of farm management 3) to practice profitable business model for e-commerce type. E-commerce type farm enterprises needs are not only technology transference but also farm management.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1997년도 제25회 춘계학술대회
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• pp.129-130
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• 1997

국내 및 해외에서 생산 되는 윤활유에 Cloud-point curves 및 상용성 개념을 도입하여 이러한 데이터를 측정할수 있는 장치를 기존의 Light scatering, Neutron scatering, Visible Method등이 아닌 He-Ne Laser를 이용하여 측정하는 장치이다. He-Ne Laser을 이용하여 공중합체 용액의 Cloud-point curves를 측정하였고, 측정 Cloud-point curves 데\ulcorner를 연속열역학적 상평형관계식에 적용 coex istence curves를 추산하였으며 추산치와 측정치를 비교 검토하였다. 멀지 않은 해에는 이러한 분석장치가 상용화되어 윤활유 제품의 상용성을 평가하는 장치가 될 것으로 사료된다. 따라서, 기존 윤활유 제품 및 신제품의 상용성(compatibility)을 He-Ne Laser을 이용하여 측정하고 다른 일면으로는 윤활유 제품의 고품질화 및 제품의 경쟁력을 강화하는데 커다란 영향을 미치리라 사료된다.

• Journal of Advanced Marine Engineering and Technology
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• 제13권3호
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• pp.37-47
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• 1989

A calcuation method of the temperature distribution for various shape due to the constant heat input is studied in this paper. So far, the method of try and error is carring out on the mould design. The reason of adopting this method is due to hardly estimate the cooling system in the mould base. As above description, the most part of the mould is supposed as a rectangular, cylinderical and triangular shape and made a governing equation of heat transfer and solved it to numerical analysis by finite-difference method(central- difference). After that in order to confirm that the temperatures are measured on different shape specimens from the part of frequent usage of which are carbon, crome-molybden, tool and stainless steel those were compared with the results of calculations presented in this paper.

• 한국유기농업학회지
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• 제19권2호
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• pp.145-156
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• 2011

This research targets housewives residing in Daegu among whole consumers. The first step is to divide housewives into two groups, group 1 which has experience of purchasing environment-friendly agricultural products and group 2 which has no experience. Then in the next step, research proceeds to investigate perception, present behavior and future intention of purchasing environment-friendly agricultural products. Based on this, it intends to provide both basic information which is needed for producers and distributors to set their systemic marketing strategy to increase consumption of environment-friendly agricultural products and effective way to vitalize the consumption.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.668-671
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• 1999

현대 사회의 컴퓨터 사용자 계층은 점점 그 범위와 수가 커지고 있다 이러한 추세는 앞으로도 계속 증가할 것이다. 따라서 많은 사람들은 더 편리하고 익히기 쉬운 컴퓨터의 사용법을 원하고 생활속에서 더 많이 컴퓨터를 활용하기를 원한다. 그러므로 인간에게 가장 친숙한 음성을 이용함으로써 이런 사용자들의 필요를 충족시킬 수 있을 뿐 아니라 사용자가 쉽게 접할 수 있도록 할 수 있다. 그러므로 본 논문의 목적은 이러한 상황에서 인간과 기계와의 인터페이스를 인간의 기본적인 의사소통 수단인 음성을 이용하여 보다 빨리 작업 할 수 있게 하는 취지에 있다. 기존의 인식알고리즘은 그 복잡성이 높을수록 인식률은 증가하나 계산시간이 많이 걸린다는 단점이 있다. 이러한 계산시간의 증가는 윈도우환경의 컴퓨터 사용시 다른 프로그램의 실행에 지장을 줄 수 있다. 따라서 인식률은 증가시키면서 인식 시간은 감소시킬 수 있는 방법들이 필요하다. 본 논문에서는 컴퓨터 사용시 쓰이는 명령어를 기본으로 하여 보다 빠른 인식 처리를 수행하기 위해 기준 패턴의 후보자를 선정하는 방법을 제안한다

• Journal of Forest and Environmental Science
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• 제11권1호
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• pp.1-21
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• 1995

본 논문은 1992년 리우환경회담 이후 변화하고 있는 세계산림자원 및 국제목재시장에 능동적으로 대처하기 위한 방안을 모색하고자 의도 하였다. 특히 우리나라의 산림자원은 III영급 이하가 90% 정도를 차지하는 어린 임분으로 아직 육성임업단계에 있으므로 해외목재자원의 확보는 필수적이며 시급한 과제이다. 따라서 안정적으로 해외목재자원을 확보하기 위한 몇가지 전략을 제시하였다.