• 경영정보학연구
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• 제7권2호
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• pp.41-59
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• 2005

본 연구는 모바일콘텐츠 중 성장 가능성이 가장 큰 것으로 예측되는 모바일게임에 대해 사용자들의 사용의도에 영향을 미치는 요인의 탐색을 위해 기술수용모델의 인지된 용이성, 인지된 유용성, 사용의도의 기본 모델에 모바일 게임특성과 모바일 디바이스의 특성, 즐거움요인을 추가로 확장하여 모바일 게이머의 게임 사용의도에 대한 영향 요인을 실증적으로 검증하였다. 그 결과 모바일게임 사용의도의 선행 요인으로 설정된 유용성과 용이성, 즐거움 요인 모두 사용의도에 유의한 영향력이 있는 것으로 나타났다. 한편 모바일 게임의 유용성 인식에는 개성표현성과 즐거움 요인은 유의한 것으로 나타났으나 용이성은 유의하지 않은 것으로 나타났으며, 인지된 용이성의 선행요인으로 설정된 자기효능감, 조작성, 화면크기, 실행속도 중에서는 자기효능감과 조작성만이 유의한 것으로 나타났다. 또한 인지된 즐거움에 영향을 미치는 요인으로 조작성, 디자인/스토리, 보상, 용이성이 유의한 것으로 나타났으며, 이중 용이성의 영향력이 가장 큰 것으로 나타났다. 통계적 검증 결과 통해 모바일 게임 콘텐츠 개발과 관련된 실무적 시사점을 도출하였다.

• Elastomers and Composites
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• 제44권3호
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• pp.196-208
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• 2009

감응 성질을 탑재한 복잡한 고분자 재료가 시장에 등장하기 시작하고 있다. 가역적이며 비공유성인 상호작용을 사용하여 이와 같은 감응형 재료를 설계하는 예가 많아지고 있다. 최근에 개발된 수소결합 단위가 이와 같은 설계 기법을 극으로 치닫게 하고 있다. 단량체를 이어주는 힘이 수소결합뿐인 초분자 고분자는 온도나 용매의 변화에 기계적 성질이 감응되는 재료를 형성한다. 본 보문에서는 수소결합으로 이루어진 초분자 고분자가 자기치유 재료로 사용되는 예를 소개한다. 재생 가능한 고무성 재료를 합성하는 일은 그리 매력적이라 할 수 없다. 그러나 상온에서 접착제를 사용하지 않고도 손상을 반복해서 치유할 수 있는 고무 재료는 우리의 상상의 나래를 펼치게 하는 재료이다. 외부의 간섭 없이 환경적 자극에 비선형적으로 감응하여 파손된 부분을 치유시키는 재료인 자기치유 재료는 여러 가지 첨단공학 계에서 엄청난 가능성을 가진 재료라 할 수 있다.

• 천문학회보
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• 제43권1호
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• pp.43.1-43.1
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• 2018

Star formation in galaxies predominantly takes place in giant molecular clouds (GMCs). While it is widely believed that UV radiation feedback from young massive stars can destroy natal GMCs by exciting HII regions and driving their expansion, our understanding on how this actually occurs remains incomplete. To quantitatively assess the effect of UV radiation feedback on cloud disruption, we conduct a series of theoretical studies on the dynamics of HII regions and its role in controlling the star formation efficiency (SFE) and lifetime of GMCs in a wide range of star-forming environments. We first develop a semi-analytic model for the expansion of spherical dusty HII regions driven by the combination of gas and radiation pressures, finding that GMCs in normal disk galaxies are destroyed by gas-pressure driven expansion with SFE < 10%, while more dense and massive clouds with higher SFE are disrupted primarily by radiation pressure. Next, we turn to radiation hydrodynamic simulations of GMC dispersal to allow for self-consistent star formation as well as inhomogeneous density and velocity structures arising from supersonic turbulence. For this, we develop an efficient parallel algorithm for ray tracing method, which enables us to probe a range of cloud masses and sizes. Our parameter study shows that the net SFE, lifetime (measured in units of free-fall time), and the importance of radiation pressure (relative to photoionization) increase primarily with the initial surface density of the cloud. Unlike in the idealized spherical model, we find that the dominant mass loss mechanism is photoevaporation rather than dynamical ejection and that a significant fraction of radiation escapes through low optical-depth channels. We will discuss the astronomical.

• 농촌계획
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• 제7권2호
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• pp.41-53
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• 2001

A village appraisal is a study of the village, carried out by the people who live there as a basis for influencing its future. It is an exciting opportunity for a village to take a good look at itself, and it is a project in which everyone can be involved. It involves gathering factual information and the opinions of local people, so as to build up an overall picture of the village. An appraisal is a questionnaire survey carried out by and for the local community. It aims to identify local characteristics, problems, needs, threats, strengths and opportunities. It is a means of taking stock of the community and of creating a sound foundation of awareness and understanding on which to base future community action. Over the past 30 years more than 2,000 village appraisals have been undertaken in rural Britain. This research examined 48 village appraisals which had been carried out in England between 1985 and 1999. The suggested strengths and weaknesses of the village appraisals are: the target of the whole population in an area; the wide-ranging in its coverage of issues; well linked to a county-wide support agency; a good tool for identifying needs and wants, and local priorities; a good tool of local democracy and of increasing self-confidence in individuals and the whole community; not an exhaustive survey; very labour intensive; too little coverage of issues relating to the local economy; the lack of any input by professional planners and so forth.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.222-222
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• 2011

Titanium dioxide (TiO2) has a number of applications in optics and electronics due to its superior properties, such as physical and chemical stability, high refractive index, good transmission in vis and NIR regions, and high dielectric constant. Atomic layer deposition (ALD), also called atomic layer epitaxy, can be regarded as a special modification of the chemical vapor deposition method. ALD is a pulsed method in which the reactant vapors are alternately supplied onto the substrate. During each pulse, the precursors chemisorb or react with the surface groups. When the process conditions are suitably chosen, the film growth proceeds by alternate saturative surface reactions and is thus self-limiting. This makes it possible to cover even complex shaped objects with a uniform film. It is also possible to control the film thickness accurately simply by controlling the number of pulsing cycles repeated. We have investigated the ALD of TiO2 at 100$^{\circ}C$ using precursors titanium tetra-isopropoxide (TTIP) and H2O on -O, -OH terminated Si surface by in situ X-ray photoemission spectroscopy. ALD reactions with TTIP were performed on the H2O-dosed Si substrate at 100$^{\circ}C$, where one cycle was completed. The number of ALD cycles was increased by repeated deposition of H2O and TTIP at 100$^{\circ}C$. After precursor exposure, the samples were transferred under vacuum from the reaction chamber to the UHV chamber at room temperature for in situ XPS analysis. The XPS instrument included a hemispherical analyzer (ALPHA 110) and a monochromatic X-ray source generated by exciting Al K${\alpha}$ radiation (h${\nu}$=1486.6 eV).

• 대한화학회지
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• 제50권6호
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• pp.506-514
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• 2006

연구는 교실 밖 화학체험학습 프로그램의 적용이 중학생들의 과학 탐구 능력과 과학 관련 태도에 미치는 영향을 알아보는 것이다. 교실 밖 화학체험학습 프로그램은 ‘재미있는 교실 밖 화학, ‘신나는 과학수업'을 위해 개발된 것으로 자연환경에 부합되는 화학체험 제재를 선정하여 자연에서 실험 소재를 구하고 일상생활 속에서 경험할 수 있는 자연친화적 화학실험으로 구성되었다. 교실 밖 화학체험학습 프로그램은 전일제 계발활동을 통하여 교실과 실험실을 벗어난 자연환경에서 적용하였다. D중학교 3학년 과학반 학생들을 대상으로 실험 집단과 비교 집단으로 나누어 실험 집단은 교실 밖 화학체험학습 프로그램에 참가시키고 비교 집단은 전통적 수업방식을 따랐다. 두 집단 사이의 과학 탐구 능력과 과학 관련 태도의 변화를 비교·분석하고 교실 밖 화학체험학습 프로그램에 대한 학생들의 반응을 알아보았다. 그 결과, 교실 밖 자연친화적 화학실험은 중학생들의 과학 탐구 능력과 과학 관련 태도를 향상시켰다. 또한 학생들의 70% 이상이 교실 밖 화학체험학습 프로그램에 긍정적인 반응을 보였으며 과학에 대한 관심과 흥미, 자발적 참여도가 높아졌다.

• 한국간호교육학회지
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• 제7권2호
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• pp.196-206
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• 2001

The purpose of this study was to identify Korean adolescents' sexual harassment conditions and patterns in schools as well as their psychological reactions when they are under sexual harassments or they committed sexual harassments. The subjects were 475 middle and high schoolers in Pusan and Gyeong Sang Nam-Do. The survey was executed from July 1 through Dec. 31, 2000. The collected data was analyzed by SPSS WIN 8.0 using percentage, mean. The results of this study were as follows: 1. the linguistic sexual harassment such as 'lewd jokes or dirty talks' was the major pattern(35.4%), The body touching such as 'kiss or embracing', 'internet transmission of pornography', 'sexual harassing of body characteristics', touching breast', 'grasping of hands or body touching', 'body touching in secret place', 'urging to sit in touch or on knees', 'exposing of special body areas', and 'showing pornography' followed in a row. 2. The eighteen point three percents of subjects had the experience to commit sexual harassment. The forty four point seven percent of above subjects committed it against their classmates. The first time to commit sexual harassment was their middle school period (38.4%). Their motives to commit it were as under: 'killing time'(48.8%), 'annoying', 'attracting attention from the other sex', 'expressing lovely emotions', 'urging of their friends', 'misunderstanding that the other partners felt good when they experienced sexual harassment, 'showing their strength' etc. their with committing harassments they felt as under ; 'joyful'(61.6%), 'funny,' 'desirous to try again', 'thrilling', 'breaking stress', very pleasant', 'exciting', 'regretful', 'guilty', and 'feeling fear' etc. 3. Twenty four point two percents of the population exposed to sexual harassments. The sexual harassers were almost their classmates (42.7%). And then unknown people', 'boy or girl friends and school staffs' followed in a row. The places where harassments happened were 'inside classroom'(69.8%), 'school bus and subway', 'outside school', etc. The feelings when experienced harassments were 'anger' (51.3%), 'hurting self-respect', 'embarrassing', 'rejection', 'insulting', 'shame', 'fear', 'dislike', 'anxiety', 'melancholy' etc. The reasons not to have consultations after sexual harassments were 'worrying to be well-known'(49.6%), 'believing not helpful enough', 'regarding simple mischief', 'trying to revenge directly', 'understanding their mistakes', 'worrying retaliation' etc.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2009년도 춘계학술대회 논문집
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• pp.111-112
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• 2009

Diamond-like carbon (DLC) is a convenient term to indicate the compositions of the various forms of amorphous carbon (a-C), tetrahedral amorphous carbon (ta-C), hydrogenated amorphous carbon and tetrahedral amorphous carbon (a-C:H and ta-C:H). The a-C film with disordered graphitic ordering, such as soot, chars, glassy carbon, and evaporated a-C, is shown in the lower left hand corner. If the fraction of sp3 bonding reaches a high degree, such an a-C is denoted as tetrahedral amorphous carbon (ta-C), in order to distinguish it from sp2 a-C [2]. Two hydrocarbon polymers, that is, polyethylene (CH2)n and polyacetylene (CH)n, define the limits of the triangle in the right hand corner beyond which interconnecting C-C networks do not form, and only strait-chain molecules are formed. The DLC films, i.e. a-C, ta-C, a-C:H and ta-C:H, have some extreme properties similar to diamond, such as hardness, elastic modulus and chemical inertness. These films are great advantages for many applications. One of the most important applications of the carbon-based films is the coating for magnetic hard disk recording. The second successful application is wear protective and antireflective films for IR windows. The third application is wear protection of bearings and sliding friction parts. The fourth is precision gages for the automotive industry. Recently, exciting ongoing study [1] tries to deposit a carbon-based protective film on engine parts (e.g. engine cylinders and pistons) taking into account not only low friction and wear, but also self lubricating properties. Reduction of the oil consumption is expected. Currently, for an additional application field, the carbon-based films are extensively studied as excellent candidates for biocompatible films on biomedical implants. The carbon-based films consist of carbon, hydrogen and nitrogen, which are biologically harmless as well as the main elements of human body. Some in vitro and limited in vivo studies on the biological effects of carbon-based films have been studied [$2{\sim}5$].The carbon-based films have great potentials in many fields. However, a few technological issues for carbon-based film are still needed to be studied to improve the applicability. Aisenberg and Chabot [3] firstly prepared an amorphous carbon film on substrates remained at room temperature using a beam of carbon ions produced using argon plasma. Spencer et al. [4] had subsequently developed this field. Many deposition techniques for DLC films have been developed to increase the fraction of sp3 bonding in the films. The a-C films have been prepared by a variety of deposition methods such as ion plating, DC or RF sputtering, RF or DC plasma enhanced chemical vapor deposition (PECVD), electron cyclotron resonance chemical vapor deposition (ECR-CVD), ion implantation, ablation, pulsed laser deposition and cathodic arc deposition, from a variety of carbon target or gaseous sources materials [5]. Sputtering is the most common deposition method for a-C film. Deposited films by these plasma methods, such as plasma enhanced chemical vapor deposition (PECVD) [6], are ranged into the interior of the triangle. Application fields of DLC films investigated from papers. Many papers purposed to apply for tribology due to the carbon-based films of low friction and wear resistance. Figure 1 shows the percentage of DLC research interest for application field. The biggest portion is tribology field. It is occupied 57%. Second, biomedical field hold 14%. Nowadays, biomedical field is took notice in many countries and significantly increased the research papers. DLC films actually applied to many industries in 2005 as shown figure 2. The most applied fields are mold and machinery industries. It took over 50%. The automobile industry is more and more increase application parts. In the near future, automobile industry is expected a big market for DLC coating. Figure 1 Research interests of carbon-based filmsFigure 2 Demand ratio of DLC coating for industry in 2005. In this presentation, I will introduce a trend of carbon-based coating research and applications.