學校 敎室內 氣候環境에 關한 硏究

李光浩,黃圭洪 全北大學校 1978 論文集 Vol.20 No.-

For this study 12 classrooms of 4 buildings Kijon Girls' School wee equipped with dry and wet-bulb psychrometers and their temperatures were recorded three times a day(at 9 a.m., at noon, at 3 p.m.) from 8th March to 23rd July, 1977 and from 22nd August to 31st October, 1977. The results are as follow: 1) Monthly average temperature and humidity show that in early spring the the temperature of 'G' room is warmer than any other room. 2) Of 66 days 57-60 days are marked by more than discomfort index 75 in 'B' 'I' 'G' rooms. 3) The correlation between temperatures of in and out was high. (Correlation coefficient, Spring : 0.60-0.92, Summer: 0.69-0.91).

A cooperative spectrum sensing scheme using adaptive fuzzy system for cognitive radio networks

Kieu-Xuan, T.,Koo, I. North-Holland [etc ; Elsevier Science Ltd 2013 Information sciences Vol.220 No.-

Cognitive radio represents a promising design paradigm for the next-generation of wireless networks that can enhance utilization of the scarce spectrum available. It allows dynamic spectrum access over temporarily unused spectrum holes that are identified by spectrum sensing. In order to enhance the sensing accuracy by taking advantage of the spatial diversity in multiple cognitive radio user networks, cooperative spectrum sensing has been proposed in the literature. However, most existing cooperative spectrum sensing schemes require knowledge of the noise variance and signal-to-noise ratio of primary signal at each node, which can add a significant transmission overhead. This paper proposes an adaptive fuzzy system-based scheme for cooperative spectrum sensing without the need for a priori network information such as the noise variance, channel state information, and characteristics of existing primary signals. Energy observations at nodes are used for online learning from the environment to make a reliable global sensing decision at a central node without further information. Simulation results show that the proposed scheme outperforms the equal-gain combination based scheme, and matches the optimal soft combination scheme in terms of sensing accuracy.

A Novel Blind Event Detection Method for Wireless Sensor Networks

Kieu-Xuan, Thuc,Choi, Sungsoo,Koo, Insoo Hindawi Limited 2014 Journal of sensors Vol.2014 No.-

The Effect of Pre-strain and Subsequent Electrically Assisted Annealing on the Mechanical Behaviors of Two Different Aluminum Alloys

Kieu-Anh Dinh,Sung-Tae Hong,Seung-Jun Choi,김문조,Heung Nam Han 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.12

The effects of pre-strain and subsequent electrically assisted annealing on the mechanical behaviors of two different (Al–Mg and Al–Si–Mg) aluminum alloys during electrically assisted dual stage forming are experimentally investigated. First, a specimen is deformed to a specific pre-strain by uniaxial tension and then automatically unloaded. After that, the pre-strained specimen is subjected to electrically assisted annealing by electric current with a fixed subsecond duration. Finally, the specimen is reloaded until fracture. Experimental results show that application of electric current with a subsecond duration induces electrically assisted annealing to both pre-strained aluminum alloys. The electric current also increases total achievable elongation until fracture during electrically assisted dual stage forming for both aluminum alloys. However, analysis of the stress–strain behavior during reloading and microstructural observations suggest that the quantitative effects of electric current on the post-electrically assisted annealing mechanical behavior and resultant microstructure are strongly dependent on the type of aluminum alloy. With the electric current density of 140 A/mm 2 , a full recrystallization followed by grain growth occurs in the pre-strained Al–Mg alloy specimens. For the pre-strained Al–Mg–Si alloy specimens, the electric current density of 140 A/mm 2 induces both annealing and solid solutioning. Together, our findings indicate that while electrically assisted annealing is effective at improving the productivity of dual stage forming of an aluminum alloy, the composition of the aluminum alloy should be carefully considered in the design of forming process utilizing the concept of electrically assisted annealing since the beneficial effect was limited for the precipitation hardening 6061-T6 aluminum alloy.

Effect of the sintering temperature on the carbonization behaviour of woodceramics from the cashew nut shell waste

Kieu Do Trung Kien,Do Quang Minh 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.1

Woodceramics is carbon ceramics with porous structures that can be used in many technical fields. In this study,woodceramics was prepared by mixing cashew nut shell waste (CNSW) and liquefied wood with a ratio of 1/0.6 and thensintered in an inert atmosphere at 700 oC-1200 oC. The influence of sintering temperature on the carbonization behavior offormed woodceramics was determined by X-ray diffraction, Fourier transforms infrared spectroscopy, Isotope Ratio MassSpectrometry measurement, and Scanning Electron Microscope/ Energy Dispersive X-Ray Analysis techniques. Theexperimental results showed that the carbon content increased when the sintering temperature increased. In addition to theincreased carbon content, the degree of graphitization of woodceramics also increased. It is represented by an increasedintensity of the (002) peaks and a decrease in the d002 value on the X-ray diffraction patterns. The SEM/EDX results alsoshowed that appeared small graphite particles in the amorphous background at 1000 oC-1200 oC. However, the d002 value ofthe samples is only in the range of 0.3339-0.4094 nm, so the structure of the formed carbon is a non-graphite structure.

일반논문 : 베트남 소수민족 전문가의 문화다양성 정책 참여경험에 관한 연구

( Kieu Trang Le ),김영순 ( Young Soon Kim ),김창아 ( Chang Ah Kim ) 인하대학교 교육연구소 2016 교육문화연구 Vol.22 No.1

본 연구는 베트남 소수민족 문화다양성 정책에 참여하는 베트남 전문가들을 대상으로 한 심층면담을 통하여 베트남의 문화정책 수립의 요건과 그 영향을 기술하고 해석하는데 목적이 있다. 이를 위해 총 6명의 연구참여자를 선정하였다. 이들은 다수민족 출신과 소수민족 출신으로구성된 베트남 문화관련 기관의 전·현직 기관장이다. 면담의 주요 질문은 베트남의 문화정책 수립과정의 참여 경험에 초점을 두었다. 심층면담, 문헌조사, 현지 조사를 통해 수집한 자료는 전사와 코딩을 통하여 의미단위를 추출하고 ``다양한 소수문화``, ``문화다양성 정책 과정``, ``문화다양성정책의 영향`` 으로 재범주화 하였다. 연구결과, 전문가들은 베트남의 문화다양성 요소로서 언어, 역사, 문화 공간, 생활문화, 풍습과 종교, 전통예술 및 관습과 관습법을 제시하였다. 베트남 문화다양성 정책의 수립 과정의 특징은 체계성, 소통의 어려움, 문화의 정제로 규정할 수 있었다. 또한 문화다양성 정책의 결과로는 소수 민족의 시혜, 가치 있는 문화에 대한 배려, 대외적 호평 등이 확인되었다. 하지만 베트남의 문화다양성은 정부의 민족 공존을 위한 많은 노력과 별도로 소수민족들이 실제 생활을 함께 함으로써 변화되는 부분이 더욱 많은 것으로 드러났다. The purpose of this study is to describe and analysis the influence of cultural policy process in Vietnam by conducting an in-depth interview of Vietnamese experts who participate in cultural policy process in Vietnam. For this purpose, we conduct in-depth interview with experts who participate in minority ethnic policy process in Vietnam. There are six research participations who are current or former heads of organizations related to culture in Vietnam. They are consisted of both majority and minority ethnic group. Questionnaire which is used in the interview focuses on cultural policy process. After transcribing and coding data collected through in-depth interview, literature research, field study, we extract these data into units of meaning, then re-categorize them as ``Diverse Minority Cultures``, ``Cultural Diversity Policy Process`` and ``Influence of Cultural Diversity Policy``. The results of this study shows that experts mentioned language & history, cultural space, living culture, custom & religions, traditional art and common law as elements of cultural diversity in Vietnam. The process of making cultural diversity policies in Vietnam could be prescribed by identity, difficulty in communication and purification of culture. It is also verified that the consideration for dispensation and valuable culture of minority ethnics as well as its public popular is result of cultural diversity policies. However, the cultural diversity in Vietnam shows that the government makes an effort for the harmony among ethnics and tries to makes separated minority ethnics to live together. It is necessary to evaluate the limitation of this study that it focused merely on recognitions of experts whose representation is on the government. Therefore, we suggest further study which analyses the recognition of Vietnamese people in general.

Fabrication of Polymerase Chain Reaction Plastic Lab-on-a-Chip Device for Rapid Molecular Diagnoses

Kieu The Loan Trinh,Hainan Zhang,강동진,강성현,Ben D. Tall,이내윤 대한배뇨장애요실금학회 2016 International Neurourology Journal Vol.20 No.S1

Purpose: We aim to fabricate a thermoplastic poly(methylmethacrylate) (PMMA) Lab-on-a-Chip device to perform continuous- flow polymerase chain reactions (PCRs) for rapid molecular detection of foodborne pathogen bacteria. Methods: A miniaturized plastic device was fabricated by utilizing PMMA substrates mediated by poly(dimethylsiloxane) interfacial coating, enabling bonding under mild conditions, and thus avoiding the deformation or collapse of microchannels. Surface characterizations were carried out and bond strength was measured. The feasibility of the Lab-on-a-Chip device for performing on-chip PCR utilizing a lab-made, portable dual heater was evaluated. The results were compared with those obtained using a commercially available thermal cycler. Results: A PMMA Lab-on-a-Chip device was designed and fabricated for conducting PCR using foodborne pathogens as sample targets. A robust bond was established between the PMMA substrates, which is essential for performing miniaturized PCR on plastic. The feasibility of on-chip PCR was evaluated using Escherichia coli O157:H7 and Cronobacter condimenti, two worldwide foodborne pathogens, and the target amplicons were successfully amplified within 25 minutes. Conclusions: In this study, we present a novel design of a low-cost and high-throughput thermoplastic PMMA Lab-on-a- Chip device for conducting microscale PCR, and we enable rapid molecular diagnoses of two important foodborne pathogens in minute resolution using this device. In this regard, the introduced highly portable system design has the potential to enable PCR investigations of many diseases quickly and accurately.

Study on sintering process of woodceramics from the cashew nutshell waste

Kieu Do Trung Kien,Phan DinhTuan,Toshihiro Okabe,Do Quang Minh,Tran Van Khai 한양대학교 세라믹연구소 2018 Journal of Ceramic Processing Research Vol.19 No.6

In this study, the sintering mechanism of woodceramics (WCs) from cashew nut shell waste (CNSW) was studied by analyzingchemical reactions and structural changes during the sintering process of of CNSW powder, liquefied wood and green bodiesof WCs at 900 oC for 60 minutes in the CO2 atmosphere. The chemical and structural properties of the products wereinvestigated by X-ray diffraction (XRD), Raman spectroscopy, Fourier Transform Infrared (FTIR), and scanning electronmicroscope (SEM). The results showed that the decomposition reactions of liquefied wood and CNSW occurred simultaneouslyto form the hard carbon and the soft carbon at high temperature. The sintering mechanism of WCs has been presented.

Determination of isoorientin levels in rat plasma by ultra-high performance liquid chromatography coupled with diode array detector and its application to a pharmacokinetic study

Kieu Trang, DoanNguyen,Kim, YuChul,Kwon, Seung-Hwan,Jang, Choon-Gon,Maeng, Han-Joo Medknow Publications 2019 Pharmacognosy magazine Vol.15 No.60

An Efficient Weight-Based Cooperative Spectrum Sensing Scheme in Cognitive Radio Systems

KIEU-XUAN, Thuc,KOO, Insoo The Institute of Electronics, Information and Comm 2010 IEICE TRANSACTIONS ON COMMUNICATIONS - Vol.93 No.8

<P>Cooperation is an attractive approach to improving the spectrum sensing performance of cognitive systems experiencing deep shadowing and fading. In this letter, an efficient weight-based cooperative spectrum sensing scheme is proposed. Simulation results show that the proposed scheme has better accuracy than “AND,” “OR,” and “half-voting” combination schemes and has similar spectrum sensing accuracy but with lower computational and communication complexity in comparison to the “optimal data fusion” rule.</P>