• 제목/요약/키워드: Behaviour Quality

검색결과 162건 처리시간 0.025초

산성황산동 용액 내에서 동판위에 녹청 형성에 관한 기초적 조사 (An Investigation on the Patination of Copper in Acidic Copper Sulfate Solution)

  • 윤승열
    • 한국표면공학회지
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    • 제5권3호
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    • pp.77-85
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    • 1972
  • A method of preparation of synthetic ignorgaic coating on copper (patina) has been presented . An Eh--pH diagram was constructed for the present Cu-H2O-SO$_4$ system using the most recently available thermodynamic data. In the path of the patination at room temperature the general behaviour of copper in acidic copper sulfate solutions with potassium chlorate as an oxidizing agent appeared to follow those predictable in this Eh-pH diagram. In the presence 0.05 molar cupric sulfate at a temperature of about 28$^{\circ}C$ a green brochantite (CuSO$_4$$.$3Cu(OH)$_2$) layer was formed on copper sheet in 20 days. In a solution having an initial pH of 3.5 the development of a brochantite coating has been observed to take place in two stages. In the first, a layer of cuprous oxide formed on the copper at a relatively rapid rate. In the ensuing step the outer layer of cuptrite was oxidized at much slower rate to form brochantite. The syntetic coatings appeared to consist of crystal-lites of brochanitite growing perpendicular to the cuprose oxide surface. The outer tips of the -crystallites were reasily broken off and gave to the layer a rather chalky character. Underneath, at the brochantite Cu$_2$O interface, however, the green layers were firmely attached. The effect of reagent concentration , solution agitation , and moderate temperature increase were investigated to improve the quality of coating. So also in a qualitative way were the effect of light.

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Temperature dependence of energy band gap for ZnO thin films

  • Hong, Myung-Seok;Hong, Kwang-Joon
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.99-100
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    • 2007
  • ZnO films on $Al_2O_3$ substrates were grown using a pulsed laser deposition method. Through photoluminescence (PL) and X-ray diffraction (XRD) measurements, the optimum growth conditions for the ZnO growth were established. The results of the XRD measurements indicate that ZnO films were strongly oriented to the c-axis of the hexagonal structure and epitaxially crystallized under constraints created by the substrate. The full width half maximum for a theta curve of the (0002) peak was $0.201^{\circ}$. Also, from the PL measurements, the grown ZnO films were observed to give free exciton behaviour, which indicates a high quality of the epilayer. The Hall mobility and carrier density of the ZnO films at 293 K were estimated to be $299\;cm^2/V\;s$ and $8.27\;{\times}\;10^{16}\;cm^{-3}$, respectively. The absorption spectra revealed that the temperature dependance of the optical band gap on the ZnO films was $E_g(T)\;=\;3.439\;eV\;-\;(5.30\;{\times}\;10^{-4}\;ev/K)T^2(367\;+\;T)$.

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학교보건지표의 해외 동향과 국제 비교 (The Trend and International Comparison of Overseas School Health Indicators)

  • 신선미
    • 한국학교보건학회지
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    • 제24권2호
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    • pp.181-189
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    • 2011
  • Purpose: The purpose of this study was to identify the trend of overseas school health indicators and to investigate indicators comparable internationally. Methods: Using the key words, school, health, indicators and policy through formal literature and web sites, the resources were used after the completeness of resources such as the presence of author, year published and place, and reproducibility was evaluated. Results: In overseas, the interest of school health indicators has increased gradually since 1960. Quality indicators as well as quantitative indicators are important as the good school health indicators. The overseas school health indicators have been very comprehensive, not only including students, but also including the expanded population such as school personnel, parents, family and community, process and outcomes, policies, social and cultural environment. The trend of school health research is from traditional issue-based to indicatorbased which makes comprehensive interpretation including development of school health service and life satisfaction. Among internationally comparable indicators, Health Behaviour in School-aged Children (HBSC) and Global School-based Student Health Survey (GSHS) were chiefly for students' health and behavior level, and the School Health Service Survey (SHS) was for school health service personnel and policy. Conclusion: Characteristics of overseas school health indicators were expanded population, and comprehensive and internationally comparable indicators. Therefore, Korea school health indicators need to be comprehensive using expanded population and qualitative indicators, and consider standardized indicators comparable internationally.

Simulation Study for a UV Water Disinfection Unit Powered by a Photovoltaic System

  • Riahi, Said;Mami, Abdelkader;Minzu, Viorel
    • International Journal of Computer Science & Network Security
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    • 제22권1호
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    • pp.175-182
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    • 2022
  • This work presents a simulation model for a specific UV disinfection system (UVDS) powered by a Photovoltaic System. The global UVDS also includes the electronic converters, Electronic Ballast, UV Lamp and Motor Pump. The equations that model the physical components' behaviour are connected to obtain a dynamic global model. The latter is converted in a Simulink/Matlab model, which allows to carry out simulation series concerning the entire UVDS. The physical parameters: the irradiation G and the temperature T, are considered as inputs. series of measurements carried out in order to show how these parameters affect the current, the voltage of the PVs and especially the value of the current of the UV lamp, on the other hand a study on the behavior and the evolution of the parameters of the motor pump such as the armature current, motor torque, speed of rotation and the water flow. The purpose of all this is to realize how important are the two parameters concerning the lamp current and the water flow because they are two very important factors to keep an adequate water quality.

A Study on the Syntagma & Paradigm by Repetition, Variation and Contrast in Ads

  • Choi, Seong-hoon
    • 예술인문사회 융합 멀티미디어 논문지
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    • 제7권9호
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    • pp.1-12
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    • 2017
  • This study is the academic work to explore the potential meanings of print advertisements. Linguistic features such as repetition, variation, contrast and phonological structure in the verbal texts of ads can give rise to shades-of-meaning or slight variations in advertising. The language of advertising is not only language in words. It is also a language in images, colors, and pictures. Pictures and words combine to form the advertisement's visual text.. While the words are very important in delivering the sales message, the visual text cannot be ignored in advertisements. Forming part of the visual text is the paralanguage of the ad. Paralanguage is the meaningful behaviour accompanying language, such as voice quality, gestures, facial expressions and touch in speech, and choice of typeface and letter sizes in writing. Foregrounding is the throwing into relief of the linguistic sign against the background of the norms of ordinary language. This paper focuses its discussion on the advertisements within the framework of the paradigmatic and the syntagmatic relationship. The sources of ads have been confined to Malboro. The ads were reselected based on purposive sampling methods.

포도 품종간 송이 부위별 생리적 특성과 수확 후 냉각과 유통성 관계 (Physiological properties of grape cluster portions between cultivars and the effect of postharvest cooling on the marketability)

  • 민정호;임병선;최윤수;이경민;김달우;황용수
    • 농업과학연구
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    • 제39권1호
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    • pp.1-8
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    • 2012
  • Rapid loss of grape berry quality after harvest occurs due to poor postharvest management. Understanding physiological properties between cultivars is required to develop practical technologies to control fast quality deterioration of tables grapes. Physiological characteristics of whole cluster, rachis and berries were examined to find their effects on postharvest behaviour of table grapes. 'Tamnara' showed high respiration rate and browning of rachis compared to 'Campbell Early'. Weight loss of rachis of 'Cheongsoo' was highest of three cultivars. Berry decay in 'Cheongsoo' begins at the connection portion between peduncle and berry, and berry decay of 'Cheongsoo' was the most severe among three cultivars. Precooling at $0^{\circ}C$ showed better results than cooling at $10^{\circ}C$ regardless of cultivars but cooling effect decreased when simulated marketing period increased up to 10 days. Plastic film wrapping was effective on reducing decay in general but not at higher marketing temperature. For successful commercialization of newly developed grapes, the inhibition technology of rachis browning in 'Tamnara' is required and decay control in 'Cheongsoo' through establishment of cold chain system is recommended.

Factors Affecting Brand and Student Decision Buying Fresh Milk: A Case Study in Ho Chi Minh City, Vietnam

  • NGO, Huan Quang;NGUYEN, Thang Quyet;LONG, Nguyen Thanh;TRAN, Tung Van;HOANG, Tri M.
    • The Journal of Asian Finance, Economics and Business
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    • 제6권3호
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    • pp.247-258
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    • 2019
  • The paper aims to examine the factors affecting brand and student decision in buying fresh milk. Combining qualitative and quantitative research methods, this study used self-completed questionnaires to investigate 520 students in Ho Chi Minh City. The results of the study show that that there are five key determinants affecting the dairy brand and student decision in buying fresh milk, including: (1) product quality, (2) fair price, (3) product promotion and customer services, (4) product convenience, and (5) reference group's attitude to the brand. In addition, it is also found that product brand has a direct and positive impact on the student decision. The finding in this study is quite different from other existing literatures in terms of the importance level of the determinants of the student decision in buying fresh milk; specifically, in deciding to buy their fresh milk, students are often interested in the promotion and customer service, the product convenience, and the reference group for the purchase, more than in the quality and price of the product. From these findings, some managerial implications are proposed for policy-makers and relevant enterprises to have appropriate policies and strategies for their business development.

파일 니트의 복합 후가공 기술에 의한 고품위 침장제품 개발에 관한 연구 - 원사 종류에 따른 원단의 물리적 특성 고찰을 중심으로 - (Development of Hi-Quality Bedding Items by Multi-Finishing System of Pile Knitted Fabrics - Physical Properties of Textile according to Yarn Types -)

  • 손은종;황영구;박신웅;최윤선;정성훈
    • 한국염색가공학회지
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    • 제29권4호
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    • pp.231-238
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    • 2017
  • There are many kinds of elements and processes for the development of high quality bedding products like fiber, high-temperature heat treatment, dyeing process, tenter drying with softening agent and multiple final finishing. Especially we examined the mechanical characteristic properties of fabrics according to different yarn types. The critical physical properties of the yarn consisting the pile knitted fabrics were obtained for the development of the hi-grade bedding items. The material property and the exhaustion behaviour of the developed pile knitted fabrics composing of different yarns were measured and observed. The physical properties of the developed fabric were evaluated through the material property analysis of the yarn, the physical nature of the pile knitted fabrics and the data of the exhaustion performance; tensile strength, tensile elongation, tearing strength, cross section of yarn types, dyeing properties etc. And then high-class of bedding items were knitted using the double raschel machine to make the pile knitted fabrics.

전기철도 집전장치의 아크량에 따른 비디오 이미지 분석 (Video Image Analysis in Accordance with Power Density of Arcing for Current Collection System in Electric Railway)

  • 박영;이기원;박철민;김재광;전아람;권삼영;조용현
    • 전기학회논문지
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    • 제62권9호
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    • pp.1343-1347
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    • 2013
  • This paper presents an analysis methods for current collection quality in catenary system by means of video image based monitoring system. Arcing is the sparking at the interface point between pantograph and contact wire when the electric trains have traction current values at speed. Percentage of arcing at maximum line speed is measurable parameters for compliance with the requirements on dynamic behaviour of the interface between pantograph and contact wire in accordance with requirement of IEC and EN standards. The arc detector and video is installed on a train aim at the trailing contact strip according to the travel direction. The arc detector presented and measured verity of value such as the duration and power density of each arc and the video image is measured a image when the arc is occurred in pantograph. In this paper we analysis of video image in accordance with power density of arcing from arc detector and compared with video image and power density of arcing so as to produce quality of arcing from image.

Contaminant transport through porous media: An overview of experimental and numerical studies

  • Patil, S.B.;Chore, H.S.
    • Advances in environmental research
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    • 제3권1호
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    • pp.45-69
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    • 2014
  • The groundwater has been a major source of water supply throughout the ages. Around 50% of the rural as well as urban population in the developing countries like India depends on groundwater for drinking. The groundwater is also an important source in the agriculture and industrial sector. In many parts of the world, groundwater resources are under increasing threat from growing demands, wasteful use and contamination. A good planning and management practices are needed to face this challenge. A key to the management of groundwater is the ability to model the movement of fluids and contaminants in the subsurface environment. It is obvious that the contaminant source activities cannot be completely eliminated and perhaps our water bodies will continue to serve as receptors of vast quantities of waste. In such a scenario, the goal of water quality protection efforts must necessarily be the control and management of these sources to ensure that released pollutants will be sufficiently attenuated within the region of interest and the quality of water at points of withdrawal is not impaired. In order to understand the behaviour of contaminant transport through different types of media, several researchers are carrying out experimental investigations through laboratory and field studies. Many of them are working on the analytical and numerical studies to simulate the movement of contaminants in soil and groundwater of the contaminant transport. With the advent of high power computers especially, a numerical modelling has gained popularity and is indeed of particular relevance in this regard. This paper provides the state of the art of contaminant transport and reviews the allied research works carried out through experimental investigation or using the analytical solution and numerical method. The review involves the investigation in respect of both, saturated and unsaturated, porous media.