• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2231-2233
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• 2001

현대사회에서 네트윅이 차지하는 비중은 점점 커져가고 있다. 따라서 네트윅을 활용할 수 있는 많은 노력들이 이루어지고 있다. 네트웍 프로토콜의 하나인 TCP/IP프로토콜을 이용한 LAN은 다른 정보를 처리하는 장치들을 연결하고, 자원을 공유하며, 고속의 통신을 가능하게하는 시스템이다. 본 논문은 TCP/IP 프로토콜과 장비와 장비 사이의 직렬 통신 방법인 RS232를 연계하는 게이트웨이를 통한 시스템 제어와 모니터링을 목적으로 하고자 한다. 제어 대상 시스템은 여러 가지의 적용이 가능하지만 본 논문을 위해 80C19SKC CPU로 제어되는 스텝 모터를 사용하였다.

• The monthly packaging world
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• s.172
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• pp.61-65
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• 2007

디스플레이용 PET필름 시장이 활황을 띌 것으로 보인다. 디스플레이용 PET필름은 확산.보호.반사 필름, 프리즘시트 등 LCD 광학필름의 원재료 격으로 국내 시장(세계약 40% 추정)은 LCD TV 등의 확산에 힘입어 올해 약 32% 정도의 고성장이 예상되고 있다. 그동안 포장재.비디오테이프∙전자부품 등 범용 PET필름 생산에 주력했던 SKC.코오롱.도레이새한 등 주요 화학.섬유 업체들이 LCD광학필름 제조에 필요한 디스플레이용 PET 필름의 생산 인프라를 확대하거나 새롭게 구축하기 시작한 것이다. 특히 그동안 기존 범용 PET 필름 생산라인의 일부를 이용해 생산했던 방식에서 탈피해 디스플레이 전용 라인을 신설, 향후 지속적인 수요확대에 대응한다는 전략을 구체화하고 있어 주목된다. 본 고에서는 (사)한국포장협회 회원사를 대상으로 조사한 내용을 바탕으로 업체별 PET 및 Nylon 시장을 살펴보도록 하겠다.

• 한국IT서비스학회:학술대회논문집
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• 2006.11a
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• pp.449-454
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• 2006

본 연구는 감리품질에 따른 감리성과와 프로젝트성과에의 영향으로 감리의뢰기관이 해당 감리기관에 재구매의도 또는 재계약의도에 대한 영향을 조사하였다. 연구결과, 설정된 연구모형을 중심으로 전반적인 분석을 수행하였으며, 경로분석 결과 모든 영향관계가 유의한 것으로 나타났다. 감리품질이 프로젝트성과와 감리효과 및 만족도에 정의 유의한 영향을 미치는 것으로 나타나 프로젝트성과와 감리 효과 및 만족도를 향상시키기 위해서는 감리품질뿐만 아니라 감리품질에 영향을 미치는 감리서비스요인에 대해 판단할 필요가 있으며, 감리효과와 만족도가 높으면 재구매에 정의 영향을 미치고, 프로젝트 성과가 높으면 재구매에 정의 영향을 미치는 것으로 나타났다.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.3
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• pp.359-364
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• 2014

Objectives: The principal aim of this study is to provide fundamental data for suggesting substantial management plan of personal air sampler by investigating current situation of work environment monitoring service provider. Materials and Methods: The questionnaires regarding a personal air sampler were sent by electronic mail to 150 institutions, except for 22 institutions which are out of business or closed temporarily, among total 172 domestic work environment monitoring service providers designated by Ministry of Employment and Labor based on 2013. The institutions which did not reply to the questionnaire for 30 days were required directly by phone call. Finally 97 institutions gave an answer to the questionnaire and therefore the respondence rate was 65%. Results: The normal operation rate of personal air sampler exceeded 70% in all the types (particle, gas and both combination) in terms of purchased year. Furthermore the personal air sampler purchased recently showed a trend of high operation rate compared to the personal air sampler purchased previously. The distribution patterns of personal air sampler In terms of manufacturers were Gillian>MSA>SKC for particle, Gillian>SKC>AMETEK for gas and Gillian>MSA>Casella for both combination, respectively. As a result, it was found that the personal air sampler manufactured by Gillian company was utilized the most in domestic work environment monitoring service provider regardless of types of personal air sampler. Conclusions: Based on the results obtained from this study, the normal operation rate according to types of personal air sampler was as follows: 94% for personal air sampler for collecting particle only, 93% for personal air sampler for collecting gas only and 89% for collecting both particle and gas. Overall, the numbers of personal air sampler possessed and operated normally in domestic work environment monitoring service provider were 5,458 and 5,062, which indicates the normal operation rate of personal air sampler in total aspect is 93%.

• Clean Technology
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• v.8 no.4
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• pp.217-222
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• 2002

The effects of initial cadmium ion concentrations (50, 100, 200, 300ppm), and feeding velocities (30, 45, 60mL/hr) on the removal ratio of cadmium ion by Pseudomonas aeruginosa ATCC 27853 immobilized in Ca-alginate gel beads in a packed-bed column reactor were investigated at operating temperature $37^{\circ}C$. The removal ratio of cadmium ion with variable initial concentration was decreased in the following order : 50ppm > 100ppm > 200ppm > 300ppm. The optimum removal conditions of cadmium ion by Pseudomonas aeruginosa ATCC 27853 were initial concentration 50ppm, feeding velocity 30mL/hr.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.307-310
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• 2003

A gene encoding streptodornase(sdc) from Streptococcus equisimilis H46A was expressed in S. equisimilis H64H sdc under the control of the streptokinase gene promoter. Secretion of the streptodornase was directed by the signal sequences of streptokinase or streptodornase. The expressed streptodornase activity from S. equisimilis H46A sdc transformant with streptokinase promoter - streptodornase coding sequence fusion vector was 2.3 fold higher than that from wild type. Construct of signal sequence region replaced by streptokinase ones was similarly expressed as a wild type. But constructs of skc or lrp core regions of streptokinase promoter streptodornase fusion were similarly expressed as in sdc mutant. In conclusion, improved expression of streptodornase by use of streptokinase promoter required the full length of promoter.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.359-361
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• 2006

As circuits become increasingly complex and devices sizes shrinks, the demands placed on global planarization of higher level. Chemical Mechanical Polishing (CMP) is an indispensable manufacturing process used to achieve global planarity. In the CMP process, Diamond Disk (DD) plays an important role in the maintenance of removal rate. According to studies, the cause of removal rate decrease in the early or end stage of diamond disk lifetime comes from pad surface change. We also presented pad cutting rate (PCR) as a useful cutting ability index of DD and studied PCR trend about variable parameters that including size, hardness, shape of DD and RPM, pressure of conditioner It has been shown that PCR control ability of pressure and shape is superior to RPM and size. High pressure leads to a decrease of cell open ratio of pad surface because polyurethane of pad is destroyed by pressure. So low pressure high RPM condition is a proper removal rate sustain. By examining correlations between RPM and pressure of conditioner, it has been shown that PCR safe zoneto satisfy proper removal rate has the range 0.06mm/hr to 0.12mm/hr.

• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.674-678
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• 1992

An instrument is described that can obtain directly the whole capacitance vs. potential curve and accurately even in dilute solutions using positive feedback for IR correction. Applying a small (7∼10 mV) triangular signal, controlled rectification of the resulting square wave using sample-and-hold circuit allows one to plot the corrected double layer capacitance over a wide potential range. Several illustrations involving the improved performance characteristics of its applicability are given and its limitations discussed.

• Macromolecular Research
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• v.13 no.1
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• pp.19-29
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• 2005

Polymer composites based on a thermotropic liquid-crystalline polymer (TLCP) and poly(butylene terephthalate) (PBT) were prepared using a melt blending process. Polymer composites consisting of bulk cheap polyester with a small quantity of expensive TLCP are of interest from a commercial perspective. The interactions between the PBT chains and the flexible poly(ethylene terephthalate) (PET) units in the TLCP phase resulted in an improvement in the compatibility of PBT/TLCP composites. TLCP droplets deformed and fragmented into smaller droplets in the PBT/TLCP composites, which resulted in TLCP fibrillation through the effective deformation of the TLCP droplets. The nucleation activities of the PBT/TLCP composites increased by adding even a small amount of the TLCP component.

• Macromolecular Research
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• v.17 no.8
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• pp.591-596
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• 2009

To trace the plasticizing effects of propylene glycol (PG) on poly(vinyl alcohol) (PVA), the rheological properties of PVA solutions in dimethyl sulfoxide (DMSO) and the physical properties of PVA films were discussed in terms of PG content. Both properties were closely related to the hydrogen bond breaking effects of PG The 6 and 12 wt% PVA solutions containing PG exhibited Bingham behavior, which was more noticeable at lower plasticizer content and higher polymer concentration. The 6 wt% PVA solutions containing more than 30 wt% PG showed a sudden decrease of viscosity over the frequency range of 0.08 and 0.2 rad/s. However, the 12 wt% PYA solutions showed no viscosity reduction even at a PG content up to 40 wt%. The glass transition temperature of the PVA/PG films was almost linearly decreased with increasing PG content but an abrupt reduction was observed at a plasticizer content 30 wt%, suggesting that the hydrogen bond breaking effects of PG on PVA became dominant between 20 and 30 wt%. This effect was further supported by the similar tendency of the tensile properties.