• Environmental Engineering Research
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• 제15권2호
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• pp.85-91
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• 2010

Romania aims to adopt and implement the European Union's legislation, also including that for the field of water management. Like other countries, groundwater in Romania is locally polluted from point sources, such as leaking landfills, as well as from diffuse pollution sources, include fertilizers, pesticides and leakages from sewers, in urbanized areas. Diffuse pollution can also occur indirectly, by over-exploitation of groundwater wells, resulting in salt water intrusion, as well as from mining and exploitation of mineral aggregates. Romania has quite an intensive monitoring scheme to measure groundwater quality in phreatic and confined aquifers. The purpose of the work resumed in this paper was to derive natural background levels (NBL) for groundwater in order to distinguish the natural elevated concentrations of some substances (natural phenomena) from point and diffuse pollution (anthropogenic phenomena). Based on these NBLs, threshold values (TV) for groundwater will be set according to the requirements of the European Water Framework Directive and the related Groundwater Directive. This paper describes the results of a study for the derivation of NBL and TV in a pilot Groundwater Body. Also, the process and draft results for extrapolating this work for all Romanian groundwater bodies is explained, as well as points for future consideration with respect to monitoring and management.

• 통상정보연구
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• 제5권1호
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• pp.85-100
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• 2003

Legal rules applying to the commerce and international commerce in particular contracts, proper law, jurisdiction and so on, have improved with time and experience. Engaging in e-commerce on the World Wide Web may expose the company to the risk of being sued in any foreign country where Internet user can establish a legal claim. The modem law of contracts is highly sophisticated and difficult to understand. With contracts created in cyberspace, the basic rules are no difference that we can find. However, there are situations in e-commerce that are altogether new and to which the existing rules cannot apply. Here uncertainty and business risk is too high for trading partners to deal with certainty. Therefore existing law must change to e-commerce law so that it provides certainty and enforceability over e-commerce. UNCITRAL Working Group on Electronic Commerce prepared the Preliminary Draft Convention on [International] Contracts Concluded or Evidenced by Data Message from the thirty-ninth session in 2002 which applies to international contracts concluded or evidenced by means of data messages. An electronic contract is concluded when the acceptance of an offer becomes effective, and an offer becomes effective when it is received by the offeree, and an acceptance of an offer becomes effective when the indication of assent is received by the offeror according to this Convention. Electronic contract may be concluded by the interaction of an automated computer system and natural person or by the interaction of automated computer systems, and a contract formed by a natural person that accesses an automated computer system of another person has no legal effect in case the neutral person made a material error in a data message.

• Wind and Structures
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• 제28권1호
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• pp.1-17
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• 2019

Internal ring beams are primary components of new ring-stiffened cooling towers. In this study, numerical simulation of the internal flow field of a cooling tower with three ring beams under wind-thermal coupling effect is performed. The studied cooling tower is a 220-m super-large hyperbolic indirect natural draft cooling tower that is under construction in China and will be the World's highest cooling tower, the influence of peripheral radiators in operating cooling tower is also considered. Based on the simulation, the three-dimensional effect and distribution pattern of the wind loads on inner surface of the cooling tower is summarized, the average wind pressure distributions on the inner surface before and after the addition of the ring beams are analyzed, and the influence pattern of ring beams on the internal pressure coefficient value is derived. The action mechanisms behind the air flows inside the tower are compared. In addition, the effects of internal ring beams on temperature field characteristics, turbulence kinetic energy distribution, and wind resistance are analyzed. Finally, the internal pressure coefficients are suggested for ring-stiffened cooling towers under wind-thermal coupling effect. The study shows that the influence of internal stiffening ring beams on the internal pressure and flow of cooling towers should not be ignored, and the wind-thermal coupling effect should also be considered in the numerical simulation of cooling tower flow fields. The primary conclusions presented in this paper offer references for determining the internal suction of such ring-stiffened cooling towers.

• 대한토목학회논문집
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• 제43권5호
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• pp.543-553
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• 2023

이 연구는 국내 공용 중인 교량 형식 중 건설 빈도가 가장 높은 RC 슬래브 교량의 공용내하력을 간단하게 평가할 수 있는 방안에 관한 것이다. 다수의 RC 슬래브 교량이 오랜 공용기간으로 인해 상당한 노후화가 진행된 상태지만, 교량의 규모 상 1, 2종 시설물에 포함되지 않아 그동안 안전 관리에 소홀한 측면이 있다. 기존의 이론적 선행연구에서는 실측 처짐 및 실측 고유진동수에 의해 도출된 처짐응답비와 강성저하율의 관계를 이용한 RC 슬래브 교량의 손상도 평가 프로세스(안)이 제시된 바 있다. 이 연구에서는 손상도 평가 프로세스(안)의 적정성을 검토하기 위해 실 교량에 대한 평가 결과를 시설물 안전법의 안전등급 및 Matsui의 노후도 지수와 비교·검토하였다. 또한 손상도 평가 프로세스(안)의 현장적용성을 향상시켜 실측 고유진동수만으로 개략적인 공용내하력을 평가하는 개선된 방안을 제시하였다. 연구결과, 10% 정도의 공용내하력 평가 결과의 오차를 허용하는 경우, 이 연구에서 제시된 방법은 노후화된 RC 슬래브 교량의 안전성 평가 및 유지보수 우선순위 산정 등에 효율적으로 활용될 수 있을 것으로 판단되었다.

• 응용통계연구
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• 제23권1호
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• pp.189-196
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• 2010

미국의 1970년 징병추출(draft lottery)은 유한 순서열 (1, 2, ..., k)의 물리적 임의화를 쉬운 일로 생각하였다가 사회적 물의가 빚어진 대표적인 사례이다. 본 소고는 숫자 1, 숫자 2, ... 등의 순서로 쌓인 k장의 카드 뭉치를 물리적으로 임의화하는 데 있어 반복 시행(repeated trial)의 역할을 밝힌다. 부수적으로 독립시행 수 n, 성공의 확률이 $\theta$인 이항분포 B(n, $\theta$)에서 성공 수가 짝수일 확률은 n이 커짐에 따라 0.5에 수렴하게 됨을 보인다.

• 대한조선학회논문집
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• 제52권1호
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• pp.25-33
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• 2015

Following the previous works on the natural frequency of heaving circular cylinder, i.e. Lee and Lee (2013) and Kim and Lee (2013), an investigation of the same spirit on the 2-dimensional cylinder of Lewis form has been conducted. As before, the natural frequency is defined as that corresponding to the local maximum of the MCFR (Modulus of Complex Frequency Response), which is given by the equation of motion in the frequency domain analysis. Hydrodynamic coefficients were found by using the Ursell-Tasai method, and numerical results for them were obtained up to much higher frequencies than before, for which the method was known as numerically unstable in the past. For a wide range of H, the beam-draft ratio, and ${\sigma}$, the sectional area coefficient, including their practical ranges for a ship, results for the natural frequency were computed and presented in this work. Two approximate values for the natural frequency, one proposed by Lee (2008) and another one by the damped harmonic oscillator, were also compared with the current results, and for most cases it was observed that the current result is between the two values. Our numerical results showed that the values of the local maximum of MCFR as well as the natural frequencye increase as ${\sigma}$ increases while H decreases. At present, extension of the present finding to the 3-dimensional ship via the approximate theory like the strip method looks promising.

• 항공우주정책ㆍ법학회지
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• 제29권1호
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• pp.161-198
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• 2014

국제우주개발기구 (가칭: 이하 ISEA이라고 호칭함)를 창설하는 아이디어는 오로지 필자의 학문적이고 이론적인 의견입니다. 우리는 달, 화성, 금성, 수성 등과 기타 천체에 있는 천연 자원을 효율적이고 신속히 개발하기 위하여 새로운 국제우주개발기구의 창설이 필요하다. 새로운 국제기구로 ISEA의 창설은 1979 년의 달 협정 제18조 및 제11조 5항에 법적인 근거를 두고 있다. ISEA를 창설하기 위한 사전절차로서 우주관계 강대국들 간에 ISEA창설에 관한 국제조약 초안의 제정이 우선 필요하다고 본다. 이 논문의 주된 내용은 (1) 서론, (2) 달 내에 있는 천연자원 (heliumn-3 등)의 공동개발, (3) 우주강대국들에 의한 달과 화성, 금성, 수성 및 다른 천체의 개발을 위한 활동, (4) 달과 화성 및 다른 천체 내에 있는 천연자원에 대한 개발과 채굴권(광업권)에 관한 법적인 문제점과 해결방안, (5) ISEA에 관한 5단계의 설립절차, (6) ISEA의 설립에 관계된 국제조약초안에 포함되어야만 할 주된 12개 항목(조항), (7) 결론 등으로 구성되어 있다. ISEA의 창설은 우주공동개발을 위하여 국제사회에서 필수적으로 요구되고 있는 협력강화로 이어질 것이며 달, 화성, 금성, 수성 및 다른 천체의 천연자원의 개발에 촉매적인 역할을 하게 되고 또한 우주강국들의 이익을 위하여 자원, 기술, 인력, 금융 등을 독립형태로 중앙 집중적으로 관리 할 수가 있다. 우주강대국들 간에 우주정책, 법, 과학, 기술 및 산업 등의 분야에서 협력증진을 위하여 ISEA의 설립은 우리들에게 꼭 필요하며 바람직한 일이다. 더욱이 ISEA의 창설은 달, 화성, 금성, 수성 및 다른 천체의 천연자원의 탐험과 개발을 함에 있어 국제협력이 더욱 필요하게 될 것이다. 마지막으로, ISEA의 기구를 설립하는 데는 정치적이 추진력이 필요할 뿐만 아니라 이에 관한 후속조치도 강구되어만 한다는 것을 유념하여야만 된다. 새로운 이념과 창의력 을 가지고 우주산업을 발전시키고 우주국들 간에 우호관계를 증진 강화시키기 위하여 반듯이 ISEA의 창설이 필요하다고 본다. 만약 UN의 우주평화적 이용위원회를 포함한 우주강대국들의 내각 수반(대통령 또는 국무총리)들이 정상회담에서 ISEA의 설립에 합의한다면 가까운 장래에 ISEA의 설립은 가능하다고 필자는 확신하고 있다.

• 설비공학논문집
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• 제28권6호
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• pp.232-241
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• 2016

Installing a ventilator for an apartment house composed of over 100 dwelling units was mandated in 2006 to improve indoor air quality. In the case of mechanical ventilators, the air change rate is kept stable, however 68% of dwellers do not operate their ventilator because of an increased electrical bill and noise. In the case of natural ventilators, the former problems are settled, but there are concerns about cold draught and an increase of heating/cooling cost. Authors are developing a heat recovery type natural ventilator which is a natural ventilator equipped with total heat recovery element, and it is expected that those problems of mechanical ventilator and natural ventilator are resolved by this. The combined type diffuser of this study is an under developed fit to the heat recovery type natural ventilator above. There are no standards to evaluate the performance for this type of diffuser. Due to this issue this study investigated the performance of the ventilation and maintained a thermal environment for the combined type diffuser by comparing it with existing diffusers. The results revealed that the performances of the combined type of diffusers showed different features from the existing ones, and was estimated to be high enough in the performances above.

• Journal of Community Nutrition
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• 제4권2호
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• pp.118-129
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• 2002

Nutrition is important in the management of diabetes mellitus, however, there are few little education materials specifically designed for older adults. The objective of this study was to develop nutrition education materials for prevention and management of diabetes moll for older adults. Materials developed were a booklet and four leaflets. The contents of materials were based on lesson plans. After several revisions of the draft of materials, illustrations and icons appropriate to the contents were designed using illustrator 9.0 and Photoshop 6.0. The booklet was composed of five chapters and 40 pages. The first chapter began with an introduction about diabetes and diabetes management by diet, exercise and medication. The second chapter dealt with ideal body weight, calculation of adequate caloric intake and food exchange list. The third chapter provided information for meal planning and sample menus. The fourth chapter focused on practical tips on nutritional care of diabetes, by providing tips on reducing sugars, fat and salt, and suggestions on eating for special occasions. The fifth chapter dealt with information in case of low blood sugars, exercise and foot care. The topics of the four leaflets were “Diabetes, what is it and care”, “Food exchange list and meal planning”, “Healthy eating for diabetes”, “Special care for diabetes low blood sugars, exercise and foot care” Each leaflet was composed of six sections and was printed in large paper (B4 size) for older adults. The draft of educational materials were re-viewed by four nutrition professionals and finally pilot-tested with ten adults aged 50 and older. The characteristics of the developed materials are as follows, i) messages are delivered using simple, specific information, ⅱ) messages focused on practical applicable tips, ⅲ) various pictures, illustrations and artwork were created and inserted to enhance understanding and interest, ⅳ) sections including risk factor assessment, calculation of ideal body weight and meal planning were designed to induce the user's participation, ⅴ) sample menus and food pictures were inserted in the booklet, vi) characteristics of older adults and transformed characteristics are diversely used to help the user feel familiarity. These materials are self-explanatory and can be used by older adults. These materials also can be used widely in nutrition education at public health centers or senior centers.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.384-389
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• 2009

일반적으로 사용자의 동작 정보는 human-computer interaction 에 유용하게 사용되는데, 이때 사용자의 의도 파악은 주로 움직임의 가속도 정보를 통해 분석된다. 그러나 일반적인 사람의 움직임은 등속 운동 및 미미한 가속도를 수반하는 경우가 많아 기존의 접근 방식으로는 사용자의 모든 움직임을 검출하기 어려운 단점이 있으며, 경우에 따라서는 부자연스러운 움직임을 유발시키기도 한다. 본 논문에서는 이러한 문제를 해결하기 위해 자연스러운 interaction 을 위한 새로운 인터페이스 방식을 제안하고 이의 활용방안에 대해 논의한다. 제안된 시스템은 중력을 기구부의 복원력으로 활용하여, 초기화와 같은 가속도계 기반의 IMU 의 공통적인 문제를 해결하고 또한 비교적 간단한 움직임으로도 다양한 신호 패턴을 생성시킬 수 있도록 하는 것에 그 목적을 둔다.