• 한국컴퓨터정보학회논문지
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• 제9권4호
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• pp.127-131
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• 2004

본 논문에서는 소규모 실습실을 대상으로 웹기반의 네트워크 트래픽 모니터링 시스템을 제안한다. 제안된 시스템은 네트워크 관리자로 하여금 네트워클 분석하여 네트워크와 시스템의 운영 및 관리, 확장. 그리고 디자인을 지원할 수 있다. 전체 시스템은 네트워크 정보를 수집하고 분석하며, 네트워크 트래픽의 실시간 분석을 지원하는 분석 서버와 서버로부터 수신된 결과를 분석하여 사용자에게 그래픽적인 데이터로 보여주는 웹기반 사용자 인터페이스인 클라이언트 시스템으로 구성된다. 제안된 시스템은 웹기반 기술인 자바로 구현되었으며 다양한 분석 기능 및 활용방안을 제공함으로써 관리자로 하여금 실습실에 대한 효율적인 관리 활동을 지원할 수 있도록 한다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.985-990
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• 2003

In order to demonstrate Advanced Spent Fuel Conditioning Process (ACP), shielding facilities such as hot cell suitable to handling radionuclides and process property will be necessary. But the construction of new facilities needs much money, man-power and time, it is now scheduled to remodel the hot cell, which has already been installed and maintained at Irradiated Material Experiment Facility (IMEF) in the Korea Atomic Energy Research Institute (KAERI). The basic structure and concrete shield wall of hot cell partly have been constructed on the base floor in IMEF building in current status. And hot cell after remodeling will be used for carrying out the lab-scale experiment of ACP. The hot cell was built in accordance with 35 curies of fe-59(1.2 MeV) as design criteria of radiation dose limit. But the radioactive source of ACP is expected to be much higher than design criteria of IMEF, shielding ability of the hot cell in the current status is unsatisfactory to the hot test of ACP. Therefore shield wall shall be reinforced with heavy concrete, steel or lead. In this paper, dose rates are calculated according to ACP source, shielding materials, etc., and reinforcement structures are determined considering the current situation of hot cells, installation of shield windows and the easiness of work.

• 한국환경과학회지
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• 제7권5호
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• pp.573-580
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• 1998

This study examined the carbon dioxide ($CO_2$) pollution inside vehicles under low ventilation condition and evaluated the Air Quality System (AQS) for in-vehicle air quality using two techniques. The low ventilation condition is not recommended in order to keep oxygen-rich condition inside vehicles. Under the low ventilation condition, the in-vehicle $CO_2$ concentrations exceeded 1,000 ppm, the air qualify guidelines in the United States, Western Europe, and Japan, indicating more oxygen deficiency inside vehicles. On the contrary, with the AQS-on condition, the in-vehicle $CO_2$ concentrations were less than 1,000 ppm fer most of the driving time, indicating that the AQS could solve the problem of $CO_2$ accumulation inside vehicles under the low ventilation condition. The AQS test conducted by comparing carbon monoxide (CO) and volatile organic compound (VOC) concentrations inside two vehicles indicated that the AQS effectively decreased the in-vehicle concentrations by 21 to 36%, as compared to medium ventilation condition with the windows closed, the vent opened, and air conditioning on. In addition, The AQS test conducted by comparing the interior and exterior concentrations indicated that the AQS effectively decreased the in-vehicle concentrations by 18 to 31%, as compared to medium ventilation condition.

• 대한기계학회논문집B
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• 제25권11호
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• pp.1535-1542
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• 2001

A high resolution digital cinematic Particle Image Velocimetry(PIV) has been developed. The system consists of a high speed CCD camera, a continuous Ar-ion laser and a computer with camera controller. To improve the spatial resolution, we adopt a Recursive Technique for velocity interrogation. At first, we obtain a velocity vector fur a larger interrogation window size based on the conventional two-frame cross-correlation PIV analysis using the FFT algorithm. Based on the knowing velocity information, more spatially resolved velocity vectors are obtained in the next iteration step with smaller interrogation windows. When the correct velocity vector at the first step is found to be critical, a Multiple Correlation Validation(MCV) technique is applied to decrease the spurious vectors. The MCV technique turns out to improve SNR(Signal to Noise Ratio) of the correlation table. The developed cinematic PIV method has been applied to the measurement of the unsteady flow characteristics of a Rushton turbine mixer. A total of 3,245 instantaneous velocity vectors were successfully obtained with 4 ms time resolution. The acquired spatial resolution corresponds to the conventional high resolution digital PIV system using a 1K ${\times}$ 1K CCD camera.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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• pp.252-257
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• 2000

This paper describes a look-ahead algorithm of PCNC(personal computer numerical control). The algorithm is based on acceleration/deceleration before interpolation never including a command error and determines a velocity value in end point of each block(or start point of each block). The algorithm is represented as following; 1) calculating two maximum arrival velocity(v1, v2) by a acceleration value, a command velocity and distance in a previous block and a next block, 2) getting a tangent velocity(v3) of the adjacent blocks, 3) choosing a minimum value among these three velocities, and 4) setting the value to a velocity of a start point of the next block(or a end point of the previous block). The proposed look-ahead algorithm was implemented and tested by using a commercial RTOS(real time operation system) on the MS-Windows NT 4.0 in a PC platform. For interfacing to a machine, a counter board, a DAC board and a DIO board were used. The result of the algorithm increased a machining precision and a machining speed in many short blocks.

• 한국생활과학회지
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• 제18권2호
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• pp.509-522
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• 2009

This is a basic study to improve air quality of school classrooms in winter time. The purposes are to check indoor thermal and air environment in school classrooms during winter and to analyze influencing factors on indoor environment. The measurements of students' physical elements with questionnaire surveys were carried out in a total of 6 classrooms. As a result, this research shows that the temperature of one classroom was below indoor thermal standard level, three classrooms had lack of heat, and two classrooms are heated much, which induce relatively low humidity. All of 6 classrooms had lack of ventilation, being high level of $CO_2$ concentration and 2 classrooms are in condition of high PM10 concentration. The majority of students(76%) answered that the cause of their 'heated space syndrome' is because of the lack of ventilation. Students' opening windows for ventilations is hardly carried out at normal times, except that indoor temperature is over standard. That is, we can suggest one of solutions, which is to enable students to operate heating and ventilating system by themselves according to students' physical condition.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2010년도 춘계학술발표대회
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• pp.24.1-24.1
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• 2010

In practical operation, the exposed surfaces may get dirty thus degrade the performance of devices. So the combination of self cleaning and antireflection is very desirable for use in outdoor photovoltaic and displaying devices, self cleaning windows and car windshields. For the purpose of self cleaning, the surface needs to be either superhydrophobic or superhydrophilic. However, in practice AR in the visible region and self cleaning are a pair of competitive properties. To satisfy the requirements for superhydrophobic or superhydrophilic surfaces, high surface roughness is required. But it usually cause severely light scattering. Photo-responsive coatings (TiO2, ZnO etc.) can lead to superhydrophilic. However, the refractive indices are high. Thus for porous structure, controlling pore size in the underwavelength scale to reduce the light scattering is very crucial for highly transparent and self cleaning antireflection coating. Herein, we demonstrate a simple method to make high performance broadband antireflection layer on the glass surface, by "carving" the surface by hot alkali solution. Etched glass has superhydrophilic surface. By chemical modification, it turns to superhydrophobic. Enhanced transparency (up to 97%) in a broad wavelength range was obtained by short time etching. Also antifogging effect has been demonstrated, which may offer advantage for devices working at high humidity environment or underwater. Compositional dependence of the properties was observed by comparing three different commercially available glasses.

• KIEAE Journal
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• 제11권6호
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• pp.127-132
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• 2011

Since the late 20th century, countries of the world have made every effort to solve environmental problems due to global warming. The Korean Government has also made various efforts on reducing energy and $CO_2$ emission under the motto of "Low-Carbon Green Growth". In order to achieve the goal to reduce energy in the construction field, severe design standards and regulations on saving energy in new buildings have been established. However, for maximizing the reduction of energy in buildings, it is time to focus on deteriorated buildings where applications of energy saving designs and techniques have been insufficient. Especially, there are little guidelines and researches on reducing energy through remodeling at deteriorated school buildings which were built over 20 years ago. This paper suggests the priority of factors to reduce energy on the remodeling process at deteriorated school buildings using the AHP(Analytic Hierarchy Process) method. For applying the AHP method, the survey of staffs in the Education Offices and board members in the Korea Institute of Ecological Architecture and Environment was conducted via e-mail. As a result, factors of insulation, daylighting, system control, and windows turned out important in the energy reducing remodeling process at deteriorated school buildings, while factors of artificial lighting, solar heating, ventilation, and system did relatively unimportant.

• 한국정보처리학회논문지
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• 제6권8호
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• pp.2020-2030
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• 1999

해상시험에서 획득되는 자료는 함정 1척당 53GB 정도의 대용량으로 고가이며, 재현이 불가능하므로 체계적인 관리가 요구된다. 본 논문에서는 각 시험별로 획득, 관리되어오던 대용량 원시자료와 다양한 분석기법을 통하여 추출한 분석자료를 통합하여 장기간 저장함과 동시에 체계적으로 관리, 제공할 목적으로 개발되어 운용중인 해상시험자료 데이터베이스 시스템에 대해서 논한다. 대용량 CD-쥬크박스를 자진 유닉스 서버와 윈도우 환경의 클라이언트로 구성된 시스템으로 현재 입력된 6003개의 검색건수를 이용하여 클라이언트/서버 각각에 대해서 성능 평가를 수행한다.

• 교육시설
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• 제15권2호
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• pp.16-26
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• 2008

This study investigates the results of planning high school facility in accordance with the scope of the 7th educational curriculum by employing user satisfaction methodology. A high school in On-Yang, built recently to fulfill the objective of the curriculum was investigated in detail. Structured interview survey on both students and teachers were done while observation of the entire facility was carried out at the same time. Based on analysis of the interview and the observation, questions were developed, and subsequently questionnaire surveys, focused on how satisfied the students were regarding the school facility and what improvements could be made, were completed. The findings suggest that the degree of variation in planning class room should be employed considerably, as well as the efficiency of route among the facility blocks. Aspects of the other planning factors such as storey height, location of doors and windows, and equipments regarding the purpose of class room are additionally discussed.