• Applied Chemistry for Engineering
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• v.10 no.7
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• pp.1092-1095
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• 1999

The well-known mixed-acid process for the aromatic nitration requires subsequent separation of spent acid, mainly dilute sulfuric acid. A novel nitration process using $HNO_3-NO_2-O_3$ was tested in a small pilot scale with 3 mol of p-nitrotoluene. Nitrogen dioxide(14.3 mol) was added three times in parts into the solution of p-nitrotoluene and $HNO_3$(6 mol) in dichloroethane. The nitration proceeded to more than 97% conversion within 5.5 h using 0.871 mol/h of ozone. As a clean process of aromatic nitration, this method is expected to replace the present process which causes the environmental problems.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.1
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• pp.115-120
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• 2016

This paper presents how LOS (Level of Service) of connectivity at railway stations is developed. Based on interview surveys to railway users at 56 railway stations, the catchment areas for railway is defined and MOE (Measures of Effectiveness) is also developed. The MOE is determined to be the weighted access time (min) and LOS "D" was set up between 45 mins and 60 mins. The 56 railway stations is evaluated based on this MOE and most of them is found to be below LOS "E". Finally some guideline for improving the LOS of accessibility. They are an expansions of accessibility facility, an expansion of bus route, an improvement of congestion roads, and expansions of parking lots for automobile users.

• Journal of the Korean Magnetics Society
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• v.11 no.4
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• pp.168-172
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• 2001

Co-Zn ferrite thin films grown on thermally oxidized silicon wafers were fabricated by a sol-gel method. Magnetic and structural properties of Co-Zn thin films were investigated by using x-ray diffractometer (XRD), atomic force microscopy (AFM), auger electron spectroscopy (AES) and a vibrating sample magnetometer (VSM). Co-Zn ferrite thin films annealed at 400 $^{\circ}C$ presented have only a single phase spinel structure without any preferred crystallite orientation. Their surface roughness of Co-Zn ferrite thin films was shown as less than 3 nm and the grain size was about 40 nm for annealing temperatures over 600 $^{\circ}C$. A moderate saturation magnetization of Co-Zn ferrite thin films for recording media was obtained in this study and there is no significant difference of their magnetic property with those external fields of parallel and perpendicular to planes of the films. The maximum value of the coercivity was obtained as 1,900 Oe for Co-Zn ferrite thin film annealed at 600 $^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.40 no.8
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• pp.784-790
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• 2003

Present investigation shows the analysis results for ceramic reinforced metal matrix composite under uniaxial transverse tensile loading. The resulting deformation, the projected damage type, and stress-strain behavior were computed depending on microstructure details such as the type of periodic reinforcement array, and the type of interface bonding. A two-dimensional finite element analysis was conducted based on the unit-cell of square, hexagonal, or diagonal periodic away For composite with strong interface bonding, the transverse stress vs. strain curve was generally increased with the increase of the ceramic volume fraction. For the composite with weakly bonded interface, however, the transverse stress vs. strain curve was reduced against the ceramic volume fraction. The decrease was caused by the interface debonding-induced stiffness reduction of the composite. For the composite of weakly bonded interface, the relative reduction rate in the final limit stress for hexagonal array was larger than that for square array. Outcome of the present study was compared favorably with the published literature data.

• Information Systems Review
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• v.9 no.3
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• pp.33-43
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• 2007

Nobody doubts about the importance of both academic and practitioner journal. Recently, however, many researchers in IS field have presented their concerns on the identity of journal of Information Systems Review (ISR). More specifically, they have been worried and concerned with the trend of deviation from the journal's original objective, which is to be the valuable practitioner-oriented journal in the IS field. With the same view in our mind, we attempt to figure out how to fix this trend. This article first analyzes the characteristics of all papers published in the ISR. Based on the findings, we present the future direction of ISR and discuss the submission guidelines about the more appropriate paper for the ISR in terms of methodology, type, and structure of paper. In addition, we propose the new review process for the newly submitted paper to the ISR. We hope this paper triggers a vigorous argument among many IS researchers and practitioners to make ISR the most prestigious outlet in the IS field.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.110-110
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• 2011

최근 국제적으로 물관리의 차세대 개념으로서 지능형 물관리(Smart Water Grid)가 활발하게 논의되고 있다. 우리나라에서도 일부 학자들을 중심으로 이에 대한 개념이 도입되고 있다. 현재까지 정리된 지능형 물관리의 개념은 최근 급성장한 정보통신기술을 활용하여 기존에 비효율적으로 운영되는 물관리의 시스템을 획기적으로 개선하자는 것이다. 따라서 이론적으로는 물의 생산, 정수, 배송 그리고 이용과 처리에 이르는 전 과정을 실시간으로 통합하여 관리하는 것이 가능하다. 국제적으로는 IBM과 Siemens 등과 같이 정보통신과 물산업을 선도하는 기업 주도의 기술개발이 진행되는 단계이다. 2000년대 초반에는 용수수급의 효율화를 위한 장치개발에 주력하였으나, 현재에는 용수수급과 관련된 제반사항에 대한 기술적 통합시스템 구축으로 적용범위를 넓히고 있다. 우리나라에서도 도시인프라 자료의 통합관리와 수질 모니터링 시스템 구축이 추진되었으며, 2010년 12월 발표된 새만금종합개발계획에서는 본격적으로 활용을 검토하고 있다. 그러나 지능형 물관리의 기술적 통합시스템 전략은 곧 심각한 제도적 장벽에 직면할 것이다. 아무리 우수한 기술적 시스템이 개발된다고 하여도 제도적 기반의 구축이 없으면 국민경제에 도움이 되는 현실적용에는 한계가 있다. 기존에 확립된 물관리의 제도적 기반으로는 한정된 지역의 좁은 영역에서 활용될 수밖에 없다. 이것은 우리나라의 물관리가 기본적으로 법적, 제도적, 행정적 차원에서 분리되어 운영되고 있기 때문이다. 본 연구는 지능형 물관리가 지향하는 기술적인 통합시스템 구축이 당면할 제도적 한계를 도출하고 이를 극복하기 위한 정책적 방향을 제시하고자 한다. 또한 2009년 국회에 제출된 물관리기본법(안)에 지능형 물관리의 개념을 도입하는 방안을 모색하고자 한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.2
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• pp.291-297
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• 2008

The solid particle erosion behaviour of unidirectional carbon fiber reinforced plastic (CFRP) composites was investigated. The erosive wear of these composites was evaluated at different impingement angles ($30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $90^{\circ}$), different impact velocities (40, 55, 60, 70m/s) and at three different fiber orientations ($0^{\circ}$, $45^{\circ}$, $90^{\circ}$). The erodent was SiC sand with the size $50-100{\mu}m$ of irregula. shapes. The result showed ductile erosion behaviour with maximum erosion rate at $30^{\circ}$ impingement angle. The fiber orientations had a significant influence on erosion. The erosion rate was strongly dependent on impact velocity which followed power law $E{\propto}\;V^n$. Based on impact velocity (V), impact angle (${\alpha}$) and fiber orientation angle (${\beta}$), a method was proposed to predict the erosion rate of unidirectional fiber reinforced composites.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.81-81
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• 2011

Sol-gel spin-coating법을 이용하여 ZnO 박막을 증착하였다. Sol 전구체 용액을 Si(100) 기판에 증착하고 전열처리(pre-heat treatment)하여 gel 상태의 ZnO 박막을 형성시킨 후 다른 속도로 냉각시켰다. Atomic force microscopy (AFM), X-ray diffraction (XRD), Raman, photoluminescence (PL)을 이용하여 냉각속도가 ZnO 박막의 구조적 및 광학적 특성에 미치는 영향을 분석하였다. 느린 속도($5^{\circ}C$/min)로 냉각시킨 ZnO 박막은 나노섬유질구조(nano-fibrous structure)를 나타내었고, 상온에서 바로 냉각시킨 ZnO 박막은 매우 매끄러운 표면(mirror-like surface)을 나타내었다. ZnO (100), ZnO (002), ZnO (101) 방향을 나타내는 회절피크가 관찰되었고, 냉각속도에 따른 ZnO 박막의 배향성을 알아보기 위하여 texture coefficient (TC)를 계산해 보았다. 상온에서 바로 냉각시킨 ZnO 박막(TC(002)=76.3%)이 느린 속도로 냉각시킨 박막(TC(002)=45.2%)보다 (002) 방향으로의 배향성이 우세하게 나타났으며, 잔류응력도 작았다. 뿐만 아니라 PL을 이용한 광학적 특성평가에서도 상온에서 바로 냉각시킨 ZnO 박막에서 더 강한 강도와 좁은 반치폭(full-width at halt-maximum)을 갖는 near-band-edge emission (NBE) 피크가 관찰되었다. 후열처리에 따른 구조적 및 광학적 특성 변화 또한 연구하였다.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.05a
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• pp.239-242
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• 2009

최근 3 차원 측정 기술을 활용한 운동 기능성의 향상을 위한 연구가 활발히 진행되고 있다. 그 예로 3 차원 인체 정보를 이용한 의복패턴 제작 시에 필요한 절개선으로 피부상에서 동작 시 늘어나지 않는 선(Lines of Non-Extension, LoNE)을 찾아내어 활용한 연구가 발표된 바 있다. 이러한 LoNE 은 기존 의복구성을 위한 봉제선이나 기능선으로 활용될 때 동작기능성을 저해하지 않는 특징이 있다. 이에 본 연구에서는 스포츠웨어에서 활동성이 큰 상체의 어깨부위에서 Lines of Non-Extension 을 탐색하고자 하였다. 연구 방법으로는 20 대 후반 남성 2 명을 대상으로 체표의 등 부분에서 3cm 간격으로 계측점을 표시한 후 3D 인체 데이터 (Cyberware, WB)를 획득하였다. 측정시의 자세는 팔을 $30^{\circ}$, $90^{\circ}$, $135^{\circ}$, $180^{\circ}$ 외전시켰다. 피부 표면에서의 길이 변화는 구획의 크기를 달리하면서 가로, 세로, 사선방향으로 동작에 따라서 측정하였다. 변화량은 정자세($30^{\circ}$)를 기준으로 A 라 하였을 때, 기준자세와의 차이가 가장 큰 변화량을 보인 자세를 B 라 하고 A 와 B 간의 차이로 계산하였다. 연구결과, NASA 의 Biosuit 에서 소개된 Iberall(1970)의 LoNE 중 진동둘레를 포함한 팔 부위와 등, 어깨 부위에서 유사한 라인을 찾았다. 본 연구에서와 같이 구획별 사선방향 피부 변화량을 측정하는 것은 피부면에 숨겨진 인간공학적 의복 기능선을 탐색하는 데 효과적임을 확인하였다.

• The Journal of the Korea Contents Association
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• v.15 no.2
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• pp.370-376
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• 2015

The aim of this study was to survey the recognition and utilization of traditional medicine among the clinical doctors who working at traditional medicine hospital in Vietnam. The survey was conducted for 3month from September to November, 2012. As a result, the highest recognized traditional medicine was acupuncture(91.4%) and herbal medicine(86.1%). Almost of respondents had ever used acupuncture(99.4%), massage or acupressure(97.6%) and herbal medicine(95.3%) in daily clinical practice. And commonly treated health problem was neurological and psychological disease(23.5%). The most used diagnostic methods were tongue diagnosis and pulse diagnosis(97.6%). This survey will help to explore the point of contact between the traditional medicine of Vietnam and Korea. This survey results could be used as basic materials to actively approach traditional medical markets through international exchange and cooperation in the future.