• JOURNAL OF ELECTRICAL WORLD
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• no.7 s.67
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• pp.22-25
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• 1982

• Korean Journal of Materials Research
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• v.7 no.7
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• pp.547-558
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• 1997

Pb(Mg$_{1}$3/Nb$_{2}$3)O$_{3}$[PMN]-PbTiO$_{3}$[PT]계 고용체의 상경계조성(MPB)영역에 대해 La을 첨가하여 변성시킨 La변성 (1-x)PMN-xPT(x=0.35) 고용체를 만들어 온도-유전율 특성, 전계유기 분극특성 및 변위특성을 조사하였다. PMN-PT의 상경영역의 조성인 x=0.35에 대해 La함량을 0-10at%까지 변화시켰다. PMN-PT계 고용체에서 PT 의 함량이 증가함에 따라 전계유기변위 및 히스테리시스 특성이 모두 증가하였다. 전계유기변위 값 $\varepsilon$ 는 능면정과 정방정의 공존영역인 MPB(x=0.35)조성에서 가장 높은 값($\varepsilon$ = 2 x $10^{-3}$)을 보여 주었다. MPB조성에 대해 La을 첨가한 계의 전계유기변위를 조사한 결과 La의 첨가량이 적을 때 (La=0-5at%)는 La의 함량이 증가함에 따라 히스테리시스 특성이 감소하였고 $\varepsilon$ 은 증가하여 고성능의 액튜에이터 재료에 적합한 조성물로 기대된다.

• Electronics and Telecommunications Trends
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• v.9 no.3
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• pp.17-31
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• 1994

중소기업의 기술혁신은 제품의 생산성을 높임으로써 궁극적으로는 새로운 영역에의 참여와 고용창출 효과를 가져올 뿐만 아니라 국가의 수출경쟁력에 이바지하는 기여도가 매우 높다. 중소기업은 규모가 작고 유기적인 조직구조의 특성상 탄력적으로 기술혁신에 대처할 수 있는 유리한 면이 있지만, 국내의 중소기업 기술혁신은 매우 열악한 상태이다. 따라서 대기업을 위주로 형성되어 있는 통합생산관리시스템(CIM)의 개념을 도입하고 산업용네트워크와 통합생산관리시스템을 적용하는 중소기업 기술혁신의 추진전략에 대해 설명하였다.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.1
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• pp.63-72
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• 2009

고령 근로자의 작업환경 실태와 건강검진 자료를 분석하여 그들의 건강한 생활과 삶의 질을 향상시킬 수 있는 정책의 기초자료를 마련하고자 시도되었다. 대상자는 부산, 경남지역에 소재하는 41개 사업장에서 유해인자에 노출되어 작업하는 공정에 있는 50세 이상 근로자 112명(남성 91명, 여성 21명)을 대상으로 소음, 분진, 유기용제, 중금속, 작업형태 및 작업강도 등을 측정, 분석하였으며, 건강검진 자료는 일반건강진단표를 이용하여 다음과 같은 결과를 얻었다. 1. 대상자의 평균연령은 54.9(남성 55세, 여성 54.7세) 세였으며, 평균근무기간은 8.7년이 였으며, 조사대상 사업장중 71.5%가 50인 이하의 근로자를 고용하고 있는 사업장이 였다. 2. 소음에 폭로 대상자 중 31.3%가 90dB(A)인 노출기준치을 초과하였으며, 그 외의 분진, 유기용제, 중금속 등의 노출기준치를 초과한 대상자는 없었다. 3. 조사대상자 중 9%는 청력이 비정상이였으며, 78.6%의 대상자는 경작업과 중등작업을 하였으며, 52.7%는 전신을 이용하여 작업하는 형태였다.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.6
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• pp.201-204
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• 2007

In this paper, fully embedded and miniaturized diplexer device has been developed and characterized for dual-band/mode CDMA handset applications. The size of the embedded diplexer is significantly reduced by embedding high Q circular spiral inductors and high DK MIM capacitors into a low cost organic package substrate. The fabricated diplexer has insertion losses and isolations of -0.5 and -23 dB at 824-894 MHz and -0.7 and -22 dB at 1850-1990 MHz, respectively. Its size is $3.9mm{\times}3.9mm{\times}0.77mm$. The fabricated diplexer is the smallest one which is fully embedded into a low cost organic package substrate.

• Journal of Labour Economics
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• v.24 no.2
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• pp.125-162
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• 2001

According to the survey results on non-standard employment, most of the non-standard workers are women and work at service jobs and some jobs that do not require firm-specific skill. Also wages of non-standard workers appear to be lower than those of standard workers by 10~19%. Non-standard workers are very much likely to be excluded from beneficiaries of economic growth because job contents and ability are not important relatively as criteria in determining their basic wage and their benefits are also much lower in severance pay and bonuses, vacations, 4 social insurances, education and training opportunities. Because of very low rate of union membership, the working conditions of non-standard workers are not expected to be improvable easily by unions. It seems that the reason of the demand increase for non-standard workers is mainly because not only an individual establishment demands quantitative flexibility in employment, but also there are tendencies of being smaller in establishment size and of growing service industries macro-economically. The number of non-standard workers are expected to increase continuously in the future, too.

• Resources Recycling
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• v.30 no.2
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• pp.61-67
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• 2021

Scraps are a byproduct of the machining process used for transforming titanium ingots into useful mechanical parts. Scraps take two forms, namely, bulky scraps, which are produced by cutting, and chipped scraps, which are produced by milling. Bulky scraps are comparatively easier to recycle because of their small surface area and less oxygen content; as a result, they pose only a small risk of explosion. In contrast, chipped scraps pose a higher risk of explosion, because of which, their recycling is complicated, resulting in most such scraps being discarded. With the aim of avoiding this waste, we proposed a novel process for converting chipped scraps into stable carbide materials. Methods typically applied to reduce particle size and impair the formation of solid solution type phase in the carbide materials were used to improve the mechanical properties of carbides prepared from chipped scraps. Our novel recycling process reduced carbide production costs and improved carbide quality.

• Korean Journal of Organic Agriculture
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• v.29 no.2
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• pp.187-207
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• 2021

This study examined the perception of farmers who employ foreign workers. A survey was conducted on 110 farms, and the main research results are as follows. First, as many farmers hire foreign workers in informal ways other than the employment permit system or seasonal worker programs, it is important to increase the number of registered foreign workers through the employment permit system or seasonal worker programs. Second, it is important to improve farmers' perception of compliance with the minimum wage, as some farmers pay wages below the legal minimum wage. Third, the subjective productivity evaluation results of farmers showed that the difference in labor productivity between foreigners and foreigners was not significant. This means that hiring foreign workers is due to other factors such as ease of management and cost rather than productivity. Fourth, many farmers were willing to hire existing foreign workers even if they paid extra wages after the expiration of the employment permit system. Finally, promotion and improvement of the additional system for foreign workers' workplaces are needed to solve problems caused by foreign employment during off-farming season.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.03b
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• pp.116-119
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• 1999

The effects of secondary phase morphology and carbon content on the plastic deformation of 0.2C-1.5Si-1.5mn TRIP(TRansformed Induced Plasticity) steel have been investigated at various annealing and bainitic transformation temperatures. The morphology of ferrite and secondary phases was controlled by the annealing temperature and the distribution of secondary phase was controlled by the bainitic transformation temperature. The secondary phase contributed to elongation and/or UTS depending on the ferrite morphology which determined deformation mode simple elongation or rotation of secondary phase along the tensile direction In case of the sample containing the granular type retained austenite the elongation was improved as carbon stabilized the austenite phase. If the film-shape retained austenite in acicular ferrite was dominant however UTS was enhanced as the transformed martensite was hardened by carbon.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.260-261
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• 2007

본 논문에서는 800MHz와 1.9GHz 대역의 시스템에 적용할 수 있는 20dB 방향성 결합기를 8층 PCB 기판에 내장하여 소형화 및 저가화 할 수 있도록 설계하였다. 방향성 결합기는 4층과 6층에 coupled line으로 적층함으로써, 다층 PCB기판을 최대한 활용하여 공간을 최소화하였다. 또한, 고유전율을 가진 필름을 이용하여, coupled line의 끝에 내장형 고용량 커패시터를 연결하여 설계하였다. 6 $\times$ 6 $\times$ 0.7 (height)$mm^3$ 크기로 설계된 방향성 800MHz 결합기의 경우 -20dB의 coupling 특성, -0.6dB의 transmission 특성, -25dB의 isolation 특성을 나타내었다. 패키징 기판에 내장된 방향성 결합기는 단말기 및 통신시스템의 소형화에 크게 기여할 수 있을 것이다.