• Title/Summary/Keyword: II-VI

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Dense Downtown vs. Suburban Dispersed: A Pilot Study on Urban Sustainability

  • Wood, Antony;Du, Peng
    • International Journal of High-Rise Buildings
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    • v.6 no.2
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    • pp.113-129
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    • 2017
  • This paper presents the initial findings of a ground-breaking two-year CTBUH-funded research project investigating the real environmental and social sustainability of people's lifestyles in a number of high-rise residential towers in downtown Chicago, and a comparable number of low rise homes in suburban Oak Park, Chicago - based on actual energy bills and other real data. The study is ground-breaking because, to date, similar studies have been mostly based on very large data sets of generalized data regarding whole-city energy consumption, or large-scale transport patterns, which often misses important nuances. This study has thus prioritized quality of real data (based on around 250 households in both high rise and low rise case studies), over quantity. In both urban and suburban cases, the following factors have been assessed: (i) home operational energy use, (ii) embodied energy of the dwelling, (iii) home water consumption, (iv) mobility and transport movements, (v) urban/suburban Infrastructure, and (vi) quality of life. The full results of this seminal study will be published in the form of a CTBUH Research Report publication in 2017. Presented below is an overview of the initial (and, currently, unverified) findings of the research, together with the limitations of the study that should be taken into account, as well as future plans for developing this important pilot study.

Morphology-Controlled Fabrication of ZnS Nanostructures with Enhanced UV Emission

  • Kim, Yeon-Ho;Jang, Du-Jeon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.587-587
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    • 2013
  • ZnS is well-known direct band gap II-VI semiconductor, and it attracts intense interest due to its excellent properties of luminescence which enable ZnS to have promising materials for optical, photonic and electronic devices. Especially, the emission wavelength of ZnS falls in the UV absorption band of most organic compoundsand biomolecules, thus it is envisaged that ZnS based devices may find applications in increasingly important fluorescence sensing. We have developed a facile and effective one-step process for the fabrication of single-crystalline and pure-wurtzite ZnS nanostructures possessing sharp band-edge emission at room-temperature having diverse length-to-width ratios. Each of nanostructures was composed of chemically pure, structurally uniform, single-crystalline, and defect-free ZnS. These features not only suppress trap or surface states emission centered at 420 nm, but also enhance UV band-edge emission centered at 327 nm, which give as-synthesized our ZnS nanostructures possible sharp UV emission at room temperature. The reaction medium consisting of mixed solvents such as hydrazine, ethylenediamine, and water as well as proper reaction time and temperature have played an important role in the crystallinity and optical properties of ZnS nanostructures. As-synthesized our ZnS nanostructures possessing sharp UV emission guarantee high potential for both fundamental research and technological applications.

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A Marketing Strategy Implementation for Korea Postal Service (마케팅 전략실행을 통한 우정서비스 경쟁력 강화방안)

  • Kim Yong-Shik
    • Management & Information Systems Review
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    • v.3
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    • pp.257-285
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    • 1999
  • Korea Postal Service(KPS) nowadays lies in competitive environment with alternative business such as door-to-door delivery service. Customers began to complain about postal service quality and ask the government to reform a public firm through management innovation. But, Korea Postal Service has not met the break-even point between it's revenue and expenditure because the service is under the government system and cannot independently make major decisions on products, pricing, services, personnel management, financial policies and etc. The objective of this study is to provide marketing planners and practitioners with some guidelines when they establish marketing strategies and to help marketers on theories and practical instructions about postal service marketing when they interact with customers. I. A field survey on both customer satisfaction and internal staff satisfaction was conducted to get some ideas for the marketing strategy planning. II. Practical guidelines and instructions were made for marketers to communicate with customers in various areas such as pricing, product, service demand, marketing channel, promotion, and etc. III. Some suggestions on marketing policies for planners and mangers in the marketing strategy were described including personnel resource as well as physical resource. IV. Special issues on small packet market and direct mail market were discussed and some alternative solutions were proposed. V. Database marketing strategy was emphasized to get new business opportunities such as direct mail, and to provide differential services to customers as much as their contribution into the profitability for KPS. VI. Cyber Post Office should be constructed on Internet to provide new services which are combined with physical material flow and information technologies.

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Effect of Rapid thermal treated CdS Films prepared by CBD (CBD법으로 성장된 CdS 박막의 급속 열처리 효과)

  • Park, Seung-Beom;Song, Woo-Chang;Lim, Dong-Gun;Yang, Kea-Joon;Shim, Nak-Soon;Lee, Sang-Kyo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.227-227
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    • 2008
  • CdS is II-VI semiconductor with a wide band gap of approximately 2.42 eV. CdS is the most popularly employed heterojunction partner to p-CdTe due to its similar chemical properties. The as-deposited films are annealed in Rapid Thermal Annealing (RTA) system in various atmosphere(Air, Vacuum and $N_2$) at $500^{\circ}C$. In this work, X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) of chemical bath deposited (CBD) CdS films on glass is carried out. In case of the annealed CdS films in $N_2$, grain size was larger than as-annealed films.

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Structural Properties of chemically deposited CdS Films on plasma treated PET (고밀도 산소 플라즈마 처리된 폴리머 기판에 성장시킨 CdS 박막의 특성 분석)

  • Song, Woo-Chang;Park, Seung-Beom;Lim, Dong-Gun;Lee, Jae-Hyeong;Park, Jong-Kuk;Park, Ha-Yong;Kim, Jeong-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.228-228
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    • 2008
  • CdS is II-VI semiconductor with a wide band gap of approximately 2.42 eV. CdS is the most popularly employed heterojunction partner to p-CdTe due to its similar chemical properties. In this work, to improvement of the surface properties of the CdS films, PET substrate is treated by high density $O_2$ plasma. CdS films are prepared by chemical bath deposition(CBD) method. In case of the PET substrate with plasma treatment for 2min, the crystalline orientation of CdS films exhibits a strong hexagonal(002). Grain size was increased from 300nm without $O_2$ plasma treatment to 380nm with an $O_2$ plasma treatment.

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Cytotoxicity of Trichothecenes to Human Solid Tumor Cells in Vitro

  • Choi, Sang-Un;Choi, Eun-Jung;Kim, Kwang-Hee;Kim, Nam-Young;Kwon, Byung-Mog;Kim, Sung-Uk;Bok, Song-Hae;Lee, So-Young;Lee, Chong-Ock
    • Archives of Pharmacal Research
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    • v.19 no.1
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    • pp.6-11
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    • 1996
  • The trichothecenes are sesquiterpenoid mycotoxins characterized by the 12,13-epoxytrichothec-9-ene ring system. We have tested cytotoxicity of several naturally-occurring or synthesized trichothecenes against human solid tumor cell lines. Among them, trichothecin(I) and $4-\beta$-Acetoxy-12,13-epoxytrichothec-9-ene (trichodermin, II) exhibited highly cytotoxic activities. 4-.betha.-Hydroxy-12,13-epoxytrichothec-9-ene (trichodermol, III) and $4-\beta$-Methoxy-12,13-epoxytrichothec-9-ene (IV) had mild cytotoxicities. But 12,13-Epoxytrichothec-9-ene-4-one (V) and $4-\beta$-Hydroxy-12,13-epoxytrichothec-9-ene(VI) had no cytotoxicities up to 10 $\mug/ml$. And in the tested cell lines, HCT15 colon cancer cell line was the most sensitive to all tested trichothecenes.

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The Relationship of Factors that Effects on Acceptance Intention in Smart Eduction (스마트교육 수용의도에 영향을 미치는 요인 간의 관계 분석)

  • Kang, Hye-Young;Lee, Jang-Ik;Kim, Sung-Wan
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2012.07a
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    • pp.141-144
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    • 2012
  • 이 연구는 스마트교육 수용의도에 영향을 미치는 요인들의 관계를 분석하는데 목적이 있다. 기존 정보기술수용모형(technology acceptance model) 관련 선행연구를 토대로, 스마트교육 수용의도에 영향을 미치는 잠재모형을 개발하였다. 잠재모형의 예비타당성 검증절차를 거친 후, 이를 통해 수정된 모형을 검증하기 위해 경기도 A 연구소의 스마트교육 체험학습프로그램을 이수한 초 중 고등학생 132명을 대상으로 설문조사를 실시하고 그 자료를 수집 및 분석하였다. 연구결과, 다음과 같은 가설들이 채택되었다. 상호작용성은 지각된 유용성에 영향을 미친다(가설 I). 상호작용성은 지각된 사용용이성에 영향을 미친다(가설 II). 상호작용성은 지각된 수용의도에 영향을 미친다(가설 III). 사회적 영향은 지각된 유용성에 영향을 미친다(가설 IV). 사회적 영향과 상호작용성은 서로 영향을 미친다(가설 V). 지각된 유용성은 수용의도에 영향을 미친다(가설 VI). 지각된 사용용이성은 수용의도에 영향을 미친다(가설 VII). 또한 연구모형의 적합도 검증 결과, $x^2$값은 6.600, 유의확률은 .086으로서 유의수준 .05에서 모형과 자료가 일치한다는 영가설이 채택되었으며, GFI, CFI, TLI 값은 각각 .98, .99, .99로 높은 적합도 수준을 보였다. 다만, RMSEA 값은 .09로서 다소 높은 값을 보이지만, 수정된 연구모형의 적합성을 해하는 수준은 아닌 것으로 판단되었다.

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On the Analysis and Improvement of Calculus for Life Science ('생명과학을 위한 수학' 강의 분석 및 개선 방안에 대한 소고)

  • Kang, Hye-Jeong;Kim, Do-Han;Seo, Seung-Hyun;Ahn, Heung-Ju;Choe, Kwang-Seok
    • Communications of Mathematical Education
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    • v.20 no.4 s.28
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    • pp.503-521
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    • 2006
  • 'Calculus for Life Science' is one of the calculus courses for students majoring life science in Seoul National University. Contrary to the other calculus courses for students in natural sciences and engineerings, in 'Calculus for life Science' we have primarily chosen computer-based curriculum that is useful to life science and so we have tried to fulfill the requirements of the students majoring life science. Like this, we are of the opinion that there are diverse requirements in life science as well as other majors in basic mathematical education of the university. Upon this view, in this research, we consider the present conditions, the points at issue and study improvements of them. In section II and III, we introduce briefly the present 'Calculus for Life Science' focused on the curriculum. In section IV, according to the course evaluations and questionnaire, we make an analysis of the present condition and the points at issue of 'Calculus for Life Science'. In section V and VI, we present the improvements of the curriculum and the several education environments.

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A Numerical Prediction of Pollutant Material Budget during the Flood and Dry Season in Gwangyang Bay (광양만의 홍수기 및 갈수기의 오염물질수지 예측)

  • Kim, Jin-Hyuk;Lee, In-Cheol;Yoon, Han-Sam
    • Journal of Ocean Engineering and Technology
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    • v.23 no.4
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    • pp.25-31
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    • 2009
  • To predict pollutants during the flood and dry season in Gwangyang Bay, the net-fluxes and pollutant material budgets of COD, T-N, and T-P were calculated in Gwangyang Bay using a 2-D hydrodynamic model. Calculating the net-flux for each area in Gwangyang Bay showed that the net-fluxes in regions IV, V, and VII were increasing, but those of regions II, III, and VI were decreasing. In budget calculations for COD, T-N, and T-P in Gwangyang Bay, it was estimated that during the dry season the COD is approximately 1.6 times higher than during the flood season. The T-N during the flood season is approximately 7 times higher than during the dry season. However, the material budget for T-P in Gwangyang Bay predicted that it is almost nonexistent. Moreover, the central part of Gwangyang Bay (Region IV) has the highest material budget of overall pollutants.

A Study of the Development of City Parks in Japan since the 1970's

  • Tsukada, Shinya;Yuzawa, Akira
    • Proceedings of the Korean Institute of Landscape Architecture Conference
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    • 2007.10b
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    • pp.54-59
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    • 2007
  • The purpose of this paper is to study the development of city parks in Japan since the 1970's. The result of investigation is as follows; (1) Regarding research of city parks since 1970, applying the qualification theory III, The researches of the park were divided into the categories as follows; ( i ) children's playground, (ii) the spatial function of green tracts of land, (iii) the evaluation of actual use viewpoint , (iv) the historical viewpoint, ( v ) the natural environment protection viewpoint, and (vi) the social capital, citizen's participation and park management viewpoint. (2) the researches of the actual use viewpoints are increasing. This trend shows that the research viewpoints have been shifted from the individual using to the various subjects of using. (3) The researches of the historical viewpoint, researches focusing on Asia are increasing. This trend shows that the research viewpoints have been shifted to the relationship between the planning and the realization. (4) The research on the natural environmental protection viewpoints has seen a large expansion from the evaluation of forest in parks. (5) The social capital, citizen's participation and park management viewpoint were increased, as well as community development and the spreading effect.

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