• Title/Summary/Keyword: InAs 양자점

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Post-filtering in Low Bit Rate Moving Picture Coding, and Subjective and Objective Evaluation of Post-filtering (저 전송률 동화상 압축에서 후처리 방법 및 후처리 방법의 주관적 객관적 평가)

  • 이영렬;김윤수;박현욱
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.8B
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    • pp.1518-1531
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    • 1999
  • The reconstructed images from highly compressed MPEG or H.263 data have noticeable image degradations, such as blocking artifacts near the block boundaries, corner outliers at cross points of blocks, and ringing noise near image edges, because the MPEG or H.263 quantizes the transformed coefficients of 8$\times$8 pixel blocks. A post-processing algorithm has been proposed by authors to reduce quantization effects, such as blocking artifacts, corner outliers, and ringing noise, in MPEG-decompressed images. Our signal-adaptive post-processing algorithm reduces the quantization effects adaptively by using both spatial frequency and temporal information extracted from the compressed data. The blocking artifacts are reduced by one-dimensional (1-D) horizontal and vertical low pass filtering (LPF), and the ringing noise is reduced by two-dimensional (2-D) signal-adaptive filtering (SAF). A comparison study of the subjective quality evaluation using modified single stimulus method (MSSM), the objective quality evaluation (PSNR) and the computation complexity analysis between the signal-adaptive post-processing algorithm and the MPEG-4 VM (Verification Model) post-processing algorithm is performed by computer simulation with several MPEG-4 image sequences. According to the comparison study, the subjective image qualities of both algorithms are similar, whereas the PSNR and the comparison complexity analysis of the signal-adaptive post-processing algorithm shows better performance than the VM post-processing algorithm.

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The effects of e-learning characteristics on e-learner's scholastic performance (이러닝 특성이 학습자의 학업성과에 미치는 영향에 관한 연구)

  • Lee, Heon-Chul;Goo, Bon-Hee
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.5
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    • pp.201-209
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    • 2009
  • RThe main object of this study is to stipulate the relation between e-learning characteristics and e-learner's scholastic performance through the integrated study model of perspective of educational technology and information technology. Using e-learning system quality, e-learning contents characteristics and interaction as independent variable, e-learner's scholastic performance as dependent variable and learning motivation as mediator, this study has examined the relationship among these variables. Two hundreds and twelve undergraduates in cyber university participated in the survey and filled out questionnaires related to this study. The main results are as followed. First, content's quality, technical quality and the support of school affairs have a significant effect on the e-learner's scholastic performance. Second, Learning motivation plays a partial mediating role in the relationship between e-learning characteristics and e-learner's scholastic performance. The meaningful implication of this study is that to improve e-learner's scholastic performance, we have to offer e-learners more customized various learning plans, learning contents and interaction between e-learners and e-learning systems.

Fabrication of Silicon Quantum Dots in Si3N4 Matrix Using RF Magnetron Co-Sputtering (RF 마그네트론 코스퍼터링을 이용한 Si3N4 매트릭스 내부의 실리콘 양자점 제조연구)

  • Ha, Rin;Kim, Shin-Ho;Lee, Hyun-Ju;Park, Young-Bin;Lee, Jung-Chul;Bae, Jong-Seong;Kim, Yang-Do
    • Korean Journal of Materials Research
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    • v.20 no.11
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    • pp.606-610
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    • 2010
  • Films consisting of a silicon quantum dot superlattice were fabricated by alternating deposition of silicon rich silicon nitride and $Si_3N_4$ layers using an rf magnetron co-sputtering system. In order to use the silicon quantum dot super lattice structure for third generation multi junction solar cell applications, it is important to control the dot size. Moreover, silicon quantum dots have to be in a regularly spaced array in the dielectric matrix material for in order to allow for effective carrier transport. In this study, therefore, we fabricated silicon quantum dot superlattice films under various conditions and investigated crystallization behavior of the silicon quantum dot super lattice structure. Fourier transform infrared spectroscopy (FTIR) spectra showed an increased intensity of the $840\;cm^{-1}$ peak with increasing annealing temperature due to the increase in the number of Si-N bonds. A more conspicuous characteristic of this process is the increased intensity of the $1100\;cm^{-1}$ peak. This peak was attributed to annealing induced reordering in the films that led to increased Si-$N_4$ bonding. X-ray photoelectron spectroscopy (XPS) analysis showed that peak position was shifted to higher bonding energy as silicon 2p bonding energy changed. This transition is related to the formation of silicon quantum dots. Transmission electron microscopy (TEM) and electron spin resonance (ESR) analysis also confirmed the formation of silicon quantum dots. This study revealed that post annealing at $1100^{\circ}C$ for at least one hour is necessary to precipitate the silicon quantum dots in the $SiN_x$ matrix.

Moderating Effects of Political Skill in the Relations Perceived Co-Workers Politics-OCBC and -Turnover Intention (동료 조직정치지각과 동료지향 조직시민행동 및 이직의도 관계에서 정치적 기술의 조절효과)

  • Lee, Eun-Kook;Ji, Sung-Ho;Kim, Mee-Sung
    • The Journal of the Korea Contents Association
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    • v.15 no.9
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    • pp.478-493
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    • 2015
  • The present study is aimed to investigate on the moderation of self-rated political skill on the relationships between perceived co-workers' politics and outcome variables (OCB toward co-workers and turnover intention). The used data for analysis was collected from 375 employees who have worked for public and private companies located in Jeju. The results are as follows. First, the main impacts of perceived co-workers politics(PCP) on OCB-C was not statistically significant, whereas the relation of PCP to turnover was positively significant. Second, moderating effects by political skill in the relationship perceived co-workers' politics and OCB-C was not significant, but the moderation in the relation perceived co-workers' politics-to-turnover intention was supported. Implications of the current study are 1) the casual effects of politics on OCB was demonstrated, in particular, the results of previous studies which was not consistent to account for the impact of politics on OCB was proved by the differentiation of research target. The result will help to understand perceived politics. In addition, moderation of political skill in the relation perceived co-workers' politics-to-turnover intention will contribute to expand researcher area of political skill.

The Study on the Perception Types of the Service Practitioners Working for Intellectually Disabled People on the Relationships with their Service Users (지적장애 이용자와의 관계에 대한 실천가의 인식유형)

  • Park, Sook-Kyung;Kim, Yong-Deug
    • Korean Journal of Social Welfare
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    • v.62 no.1
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    • pp.367-389
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    • 2010
  • The purpose of this study is to find out perception types of service practitioners working for intellectually disabled adults on the relationships with their service users who use residential and domiciliary care services. For this purpose, this study adopted two research methods: Q-methodology and survey. This study found out three major types of practitioners' perception on the relationships with their service users. The first is the type of superficial orientation for equal relationship. The second is the type of reflective recognition on the driven relationships by practitioners. The third is that of compassionate at the advocacy for service users. In the result of survey in which respondents are practitioners working in residential care homes, small group homes and community service centers, 48.2% of respondents show the first type, 40.5% the second, 11.1% the third. Recently, in the area of personal social service for the intellectually disabled people, the importance of service users' participation and self-determination in the process of service provision is gaining higher concerns. In this context, making change on relationships between service workers and users is raised as important issue. In this environment, the results of this study could be useful to develop equal and supporting relationships.

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A Study on the Problems in the Use of CCTV by the Police and Some Proposals (경찰CCTV 운용상의 문제점과 개선방안)

  • Lee, Sang-Won;Lee, Seung-Chal
    • Korean Security Journal
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    • no.10
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    • pp.215-242
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    • 2005
  • As CCTV can be an effective tool to prevent or suppress crime at low cost, they have been widesoread in developed countries. In spite of their effectiveness, they infringe some constitutional rights such as the right to privacy, the right of likeness and the right to control over personal information. The police and ward offices install CCTV in public areas to prevent crimes without a legal basis or standard. When information obtained in such a way is used as investigation data for the police or as an evidence in a court, it can cause serious trouble. To solve this problem, legal restriction on the installation of CCTV as should be clearer. Since current laws on public agencies' protection of personal information are too general, they are not effective enough to protect personal information. Therefore, Personal Information Protection Organic Act should be enacted to make a legal basis for protecting comprehensive personal information. It should be obvious who installs CCTVs, who pay for the cost and how they are managed. Before installation, the police and ward offices should obtain residents' consent through a public hearing or voting (on the range and purpose of installation), or conduct an impact assessment. During installation, CCTVs should be limited to prevent or suppress crimes, keep public order and void dangers. In case of making a sign of installation, it must specify its rights. After installation(operation/management phase), they should abide by principles of information protection and try not to infringe constitutional right. In the cognitive aspect, the police should constitutional rights must be secured although it is important to carry out their missions. The police should serve citizens and change to the police of communities. Citizens should understand that constitutional right can be infringed if public order is not maintained. When citizens cooperate with the police, they fear of crimes will decrease.

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Influence of User-Motivation on User-Commitment in Social Media: Moderating Effects of Social Pressure (소셜미디어 이용 동기가 이용자 몰입에 미치는 영향: 사회적 압력의 조절효과)

  • Bae, Jee-Woo;Park, Cheong-Yeul
    • The Journal of the Korea Contents Association
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    • v.15 no.1
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    • pp.462-474
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    • 2015
  • This article is aimed to investigate the role of social pressure in the influential relationship of user motivation on user commitment in social media. On this purpose, user motivation in social media was divided into 3 sub-dimensions as social motivation, functional motivation and hedonic motivation and social pressure was also categorized into informational isolation pressure and conformity pressure and then it was explored that how the social pressure makes differential effects in the relationship of each dimensions of user motivation and user commitment. Major findings are as follows. First, user's social motivation and hedonic motivation in social media had significant positive influence on user commitment. Second, the informational isolation pressure showed moderating effect in the relation of functional motivation and commitment. Third, conformity pressure displayed moderating effect in the relation of social motivation and commitment. This article suggests empirical supports about the role of social pressure in the phenomena of social media use and commitment, but requires to explore more specific factors and multi-dimensional studies in regard of social pressure in social media.

Introducing Contract-out in the Policing Service : Focusing on Policing segregated System (치안서비스의 민간위탁 도입에 관한 연구 : 치안분업모델을 중심으로)

  • Choe, Jung-Taek
    • Korean Security Journal
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    • no.12
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    • pp.309-333
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    • 2006
  • These days, the majority of public service area presents increment of utilizing a contracting-out with the following reasons such as cost-efficiency, maintenance of population changes in flexible manner, and convenience of management. The social changes have influence on policing structure and regional security system as well as problems associated with accepting the contracting-out in the public policing sector. However, many issues such as limited contracting-out sector, difficulty of encouragement of participation to private sector, and limitation of making a contract with contracting-out would be brought up when initiate contracting-out to the public policing sector. Changing security system to lower budget, planning restructure of organization, developing alterable partial contracting-out, establishing private and public cooperate system and rationalizing contract system are the suggestions to solve and modify the raising problems. This study suggests a differentiate regulation of policing services compare to currently existing contracting-out method to consider a distinctive working environment. The suggestions are as follows: 1. develop a security segregate model, 2. build a cooperative system between private and public policing sector, 3. broaden opportunity of participation of private policing sector, 4. open-competition among qualified private tender to make a contract. The private contracting-out in the public security service sector should be manage in different manner compare to other private contracting-out in government-oriented public service sector. Since work performance of each private contracting-out agency is strongly bond to safety of every civilian in the nation, it is essential to increase its standard of qualification of each agency.

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Mediating Effects of Emotional Labor in the relationships between Communication Ability and Customer Oriented Behaviors: Focusing upon Self-Employed Businessmen (소상공인 커뮤니케이션 능력과 고객지향적 행동 관계에서 감정노동의 매개효과)

  • Moon, Joung Hyun;Lee, Dong Cheol;Kim, Jae-pil
    • The Journal of the Korea Contents Association
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    • v.16 no.3
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    • pp.376-390
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    • 2016
  • The purpose of present study is to investigate mediating effects of emotional labor in the links between communication ability of small businessmen and customer orientation behavior. In detail, it is demonstrated both impacts of communication ability on customer orientation behavior and emotional labor (surface acting, deep acting), and of emotional labor (surface acting, deep acting) on customer orientation behavior. Furthermore, mediating effects of emotional labor (surface acting, deep acting) will be verified. The data for analysis was collected from 270 employees in small businessmen located in Jeju. The results are as follows. First, the main impacts of communication ability on customer orientation behavior and emotional labor (surface acting, deep acting) were statistically significant, in addition, emotional labor (surface acting) was positively associated with customer orientation behavior. Surface acting as a mediator was partially mediated the relation. The result will help to understand the importance for communication ability in small businessmen, and it suggests the crucial implecation in the communication study of service suppliers.

Comparative Analysis of Trade-Labor Linkage in FTAs of the US and EU (미국과 EU의 FTA에 나타난 무역-노동기준 연계에 관한 비교 분석)

  • Kang, Yoo-Duk;Ko, Bo-Min
    • Korea Trade Review
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    • v.41 no.3
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    • pp.1-25
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    • 2016
  • This study reviews international discussions about the trade-labor linkage and examines the labor chapters of FTAs enforced by the US and the EU from a comparative perspective. Since early 1990s, starting from the NAFTA, the US has included forceable labor provisions in its FTAs and this trend continues to the TPP which was concluded in October 2015. On the other hand, the EU's labor provisions in its FTAs have been composed of promotional elements on labor rights based on cooperations and dialogues. These different features of labor provisions in the US and European FTAs are mainly due to the motives of the FTAs of the US and the EU respectively as well as their domestic situations with regards to domestic law and institutional set-ups. The coordination of labor provisions involves a long-term institutional as well as regulatory convergence which triggers not only economic but also social changes, compared to a relatively short-term effect of tariff elimination. For Korea which has been a FTA partner country both with the US and the EU, it is significant to keep the different characteristics in the labor provisions in mind, particularly in the process of its implementation. Concerning the implementation of Korea-US FTA, it might be problematic if Korean law and its regulatory practice on labor-management relations do not comply with that of the US. The Korea-EU FTA case can also have an indirect impact on Korea's labor laws since it stipulates in its provisions that both parties should have discussions not only within each government but also with the civil communities including NGOs. Thus, Korea should pay more attention to the true meaning in labor provisions of both FTAs in order to promote its firms to be equipped with the right labor-management system in their operations abroad.

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