• Title/Summary/Keyword: Key distribution

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An Ontological Question (디지털-재현, 오래된 존재론적 질문의 재등장)

  • KIM, Seongtae
    • Trans-
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    • v.5
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    • pp.1-27
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    • 2018
  • What is 'analyzing a movie'? And, what is 'its role in film studies'? The question required a systematic and scholarly answer, and filmologie was making a clear place for itself. Through psychology, aesthetics, text theories and of course semiotics, the conceptualization of 'film' has been formed. Deleuze, who has been continually writing about 'movies' in his philosophical essays, ended the debate in defining the relationship between 'image and essence' when he released 《Movie 1, Movement-Image》 in 1983. 'Film' rapidly became the topic of the century and became a 'device' that leads the way of thinking. The reason why Jean-Louis Boissier labeled this 'film' as 'device (le dispositif)' was not part of film studies. What should be noted is that the mention of 'film' became a key part of the debate of 'reproduction', which was the most popular subject of philosophy and humanities. In the digital era, the film is once again questioned about its definition. In retrospect, themes of core debates of 'History of cinema' have always been driven by simple and superficial technological changes. With the emergence of CG (Computer Graphics), the question of 'cinema' in the 21st century is not only a philosophical discussion on the problem of 'reproduction', but also a crucial change that shifted the focus of the debate on the nature of the film from 'production' to 'distribution'.

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Numerical Study of Warpage and Stress for the Ultra Thin Package (수치해석에 의한 초박형 패키지의 휨 현상 및 응력 특성에 관한 연구)

  • Song, Cha-Gyu;Choa, Sung-Hoon
    • Journal of the Microelectronics and Packaging Society
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    • v.17 no.4
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    • pp.49-60
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    • 2010
  • Semiconductor packages are increasingly moving toward miniaturization, lighter and high performance. Futhermore, packages become thinner. Thin packages will generate serious reliability problems such as warpage, crack and other failures. Reliability problems are mainly caused by the CTE mismatch of various package materials. Therefore, proper selection of the package materials and geometrical optimization is very important for controlling the warpage and the stress of the package. In this study, we investigated the characteristics of the warpage and the stress of several packages currently used in mobile devices such as CABGA, fcSCP, SCSP, and MCP. Warpage and stress distribution are analyzed by the finite element simulation. Key material properties which affect the warpage of package are investigated such as the elastic moduli, CTEs of EMC molding and the substrate. Geometrical effects are also investigated including the thickness or size of EMC molding, silicon die and substrate. The simulation results indicate that the most influential factors on warpage are EMC molding thickness, CTE of EMC, elastic modulus of the substrate. Simulation results show that warpage is the largest for SCSP. In order to reduce the warpage, DOE optimization is performed, and the optimization results show that warpage of SCSP becomes $10{\mu}m$.

Synopsis of Dragonet Fish, Family Callionymidae (Pisces, Perciformes) form Korea (한국산(韓國産) 돛양태과(科)(농어목(目)) 어류(魚類)의 분류(分類))

  • Lee, Chung-Lyul;Kim, Ik-Soo
    • Korean Journal of Ichthyology
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    • v.5 no.1
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    • pp.1-40
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    • 1993
  • Fourteen species and four genera of the family Callionymidae from Korea were reviewed and provided a tentative the key to species and genera. The taxonomic position and scientific name of the family Callionymidae were recheked together with states of their distribution. Among them, two species Callionymus kitaharai and C. doryssus previously described by Chyung(1977), were found to be the same species under synonym of Repomucenus huguenini. On the other hand, two species Repomucenus leucopoecilus and Repomucenus sp. were newly added. Seven species, previously reported as the family Callionymidae from Korea, were transferred into another generic name or specific name Draculo mirabilis into Eleucherochir mirabilis, Callionymus joponicus into Callurichthys japonics, Callionymus altivelis into Synchiropus altivelis, Callionymus kitaharai into Repomucenus huguenini, Callionymus richardsoni into Repomucenus curvicornis, Callionymus lunatus into Repomucenus lunatus, Callionymus flagris into Repomucenus oalenciennei. The species of Calliurichthys japonicus, Repomucenus lunatus, Repomucenus curvicornis, Repomucenus huguenini, Repomucenus ualenciennei and Synchiropus altivelis were mainly distributed in the South Sea, while the other species of the family were mainly distributed in the Yellow Sea of Korea.

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Broadcast Encryption System Using Secret Sharing and Subset Difference Methods (비밀분산 기법과 Subset Difference 기법을 이용한 브로드캐스트 암호시스템)

  • Lee, Jae Hwan;Park, Jong Hwan
    • Journal of Broadcast Engineering
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    • v.20 no.1
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    • pp.92-109
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    • 2015
  • Broadcast encryption is a cryptographic primitive that allows a sender to securely broadcast a message to a set of receivers. The most influential broadcast encryption system was proposed in 2001 by Naor, Naor, Lotspiech, based on a pseudo-random generator and the Subset Difference (SD) method. In this paper, we suggest a new broadcast encryption system that is based on secret sharing and SD methods. On an efficiency aspect, our system achieves O(r) transmission cost, O($log^2n$) storage cost, and O(1) computational cost for the number n of users and the number r of revoked users. Compared to O(log n) computational cost in the previous SD method, our system has the advantage that it needs only constant-sized computational cost for decryption, regardless of the number n or r. On a security aspect, our system can achieve tighter security reduction than the previous SD method and the gap of security loss is about O(n log n). Moreover, our result shows that it is possible to give the effect of the SD method while using an information-theoretically secure key distribution technique as in the Complete Subtree method.

Dual Clusters of the Metropolitan Region: A Comparative Study on the Spatial Agglomeration, Social Capital Formation, and Institutionalization of Dongdaemun Market and Seoul Venture Valley in Seoul, Korea (서울 신신업집적지 발전의 두 유형: 동대문시장과 서울벤처벨리의 산업집적, 사회적 자본의 형성과 제도화 특성에 대한 비교)

  • 남기범
    • Journal of the Economic Geographical Society of Korea
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    • v.6 no.1
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    • pp.45-60
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    • 2003
  • As the process of economic globalization deepens market uncertainty and severe competition, modern companies are tend to rely on non-market, socio-economic mechanisms such as trust, collaboration, and interdependence, They are being more influenced by cultural economic mechanisms like networks, embeddedness, and placeness rather than explicit cost-reductions. This paper analyzes the characteristics of industrial clusters, the formation of social capital, and the process of institutionalization by comparing two distinctive types of clusters, say Teheran and East-Gate Valleys in Seoul, Korea. The one is mainly consisted of IT industries with increasing vertical integration supported by venture capitals and favorable business infrastructures. The other cluster has long been a traditional CBD frame of Seoul and has transformed to the most dynamic and productive area, characterized by one-stop 'R&D-production-distribution-consumption-after sales services'. The study of the developmental trajectory and key characteristics for these kinds of clusters can give us insight for the cluster theory. This paper firstly reviews the similarities and differences between the social capital in general and that of industrial clusters. It then profiles the growth of the two clusters over the past decade, and compares the current spatial and business structure of the two clusters, focusing on transactions costs, the creation and flow of information, and the local institutions. The paper concludes with some comments about the prospects and perils of the two types industrial clusters of Seoul.

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Characterization of New Avalanche Photodiode Arrays for Positron Emission Tomography

  • Song, Tae-Yong;Park, Yong;Chung, Yong-Hyun;Jung, Jin-Ho;Jeong, Myung-Hwan;Min, Byung-Jun;Hong, Key-Jo;Choe, Yearn-Seong;Lee, Kyung-Han
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2003.09a
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    • pp.45-45
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    • 2003
  • The aim of this study was the characterization and performance validation of new prototype avalanche photodiode (APD) arrays for positron emission tomography (PET). Two different APD array prototypes (noted A and B) developed by Radiation Monitoring Device (RMD) have been investigated. Principal characteristics of the two APD array were measured and compared. In order to characterize and evaluate the APD performance, capacitance, doping concentration, quantum efficiency, gain and dark current were measured. The doping concentration that shows the impurity distribution within an APD pixel as a function of depth was derived from the relationship between capacitance and bias voltage. Quantum efficiency was measured using a mercury vapor light source and a monochromator used to select a wavelength within the range of 300 to 700 nm. Quantum efficiency measurements were done at 500 V, for which the APD gain is equal to one. For the gain measurements, a pencil beam with 450 nm in wavelength was illuminating the center of each pixel. The APD dark currents were measured as a function of gain and bias. A linear fitting method was used to determine the value of surface and bulk leakage currents. Mean quantum efficiencies measured at 400 and 450 nm were 0.41 and 0.54, for array A, and 0.50 and 0.65 for array B. Mean gain at a bias voltage of 1700 V, was 617.6 for array A and 515.7 for type B. The values based on linear fitting were 0.08${\pm}$0.02 nA 38.40${\pm}$6.26 nA, 0.08${\pm}$0.0l nA 36.87${\pm}$5.19 nA, and 0.05${\pm}$0.00 nA, 21.80${\pm}$1.30 nA in bulk surface leakage current for array A and B respectively. Results of characterization demonstrate the importance of performance measurement validating the capability of APD array as the detector for PET imaging.

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Gene-gene Interaction in Cerebral Infarction Patients : A Study on Relationship Between Apolipoprotein E, ACE Gene Polymorphism and Sasang Constitution

  • Kim Jong Kwan;Kim Hyoung Soon;Bae Young Chun;Lee Sang Min;Kim Kyung Yo;Joo Jong Cheon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.4
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    • pp.1192-1198
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    • 2004
  • Sasang Constitutional Medicine is a major branch of Korean Traditional Medicine. The differences of disease susceptibility to be shown in Sasang constitution may be due to genetic factors. Therefore, I examined interrelationship among cerebral infarction (CI), apolipoprotein E (apo E) gene polymorphism, and Sasang constitutional classification. Apo E is a key protein modulating the highly atherogenic apoB containing lipoproteins and is a candidate gene for the development of coronary artery disease (CAD). The ε2 and/or ε4 alleles were the first to be implicated in premature CAD, which resulted in this polymorphism being extensively studied. I investigated the association between apo E genotype and CI by case-control study in a Korean population. I also classified CI patients and control group into groups according to Sasang Constitutional Medicine. 218 CI patients and 379 controls without CI were examined. Apo E genotype was determined by 8% polyacrylamide gel separation after DNA amplification. A frequency of apo E ε3/ε3 in the apo E genotype distribution was higher in the CI patients compared with that in controls. Also, it was widely known that Taeumin was easily attacked with CI, but there was no association between apo E polymorphim and Taeumin. However, the Taeumin constitution did not enhance the relative risk for CI in the subjects with apo E ε2 and/or ε4 alleles. No differences in the apo E genotypes frequencies were observed in the Taeumin compared with that in the other constitutions. In addition, I investigated whether the DD(deletion/deletion) or ID(insertion/deletion) genotype of angiotensin converting enzyme (ACE) gene, a candidate gene for CI, was associated with CI, Taeumin constitution, and apo E polymorphism. As a result, the frequency of Taeumin constitution was significantly higher in CI patients with both apo E ε3/ε4 and ACE ID/DD genotypes than in the remaining Sasang constitutions. In summary, it was concluded that the apo E polymorphism is a major risk factor for CI in Koreans and the ACE ID/DD genotype enhanced the relative risk for CI in the subjects with apo E ε3/ε4 genotype and Taeumin constitution.

Estimation of Disease Code Accuracy of National Medical Insurance Data and the Related Factors (의료보험자료 상병기호의 정확도 추정 및 관련 특성 분석 -법정전염병을 중심으로-)

  • Shin, Eui-Chul;Park, Yong-Mun;Park, Yong-Gyu;Kim, Byung-Sung;Park, Ki-Dong;Meng, Kwang-Ho
    • Journal of Preventive Medicine and Public Health
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    • v.31 no.3 s.62
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    • pp.471-480
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    • 1998
  • This study was undertaken in order to estimate the accuracy of disease code of the Korean National Medical Insurance Data and disease the characteristics related to the accuracy. To accomplish these objectives, 2,431 cases coded as notifiable acute communicable diseases (NACD) were randomly selected from 1994 National Medical Insurance data file and family medicine specialists reviewed the medical records to confirm the diagnostic accuracy and investigate the related factors. Major findings obtained from this study are as follows : 1. The accuracy rate of disease code of NACD in National Medical Insurance data was very low, 10.1% (95% C.I. : 8.8-11.4). 2. The reasons of inaccuracy in disease code were 1) claiming process related administrative error by physician and non-physician personnel in medical institutions (41.0%), 2) input error of claims data by key punchers of National Medical Insurer (31.3%) and 3) diagnostic error by physicians (21.7%). 3. Characteristics significantly related with lowering the accuracy of disease code were location and level of the medical institutions in multiple logistic regression analysis. Medical institutions in Seoul showed lower accuracy than those in Kyonngi, and so did general hospitals, hospitals and clinics than tertiary hospitals. Physician related characteristics significantly lowering disease code accuracy of insurance data were sex, age group and specialty. Male physicians showed significantly lower accuracy than female physicians; thirties and fortieg age group also showed significantly lower accuracy than twenties, and so did general physicians and other specialists than internal medicine/pediatric specialists. This study strongly suggests that a series of policies like 1) establishment of peer review organization of National Medical Insurance data, 2) prompt nation-wide expansion of computerized claiming network of National Medical Insurance and 3) establishment and distribution of objective diagnostic criteria to physicians are necessary to set up a national disease surveillance system utilizing National Medical Insurance claims data.

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The Study of Diffusion and Outlook for Smart Phone in Smart Nomad Era (스마트 노매드 시대 스마트폰의 확산과 전망에 대한 연구)

  • Nam, Chong-Hoon
    • Journal of Digital Contents Society
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    • v.11 no.3
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    • pp.315-322
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    • 2010
  • This study focused on mobile trend in diffusion of smart phone. Presently, it has been evolved from digital nomad to smart nomad. Smart nomad era is based on digital technology with mobility and being smart. Smart nomad that is made up high-end device and intellectual content has changed structure of industry and life style. Smart phone is a core key in smart nomad era. In 2010 smart phone has been distributed about 2.5 hundreds million which is 20% of whole mobile phone sales and the volume of smart phone sales will be getting bigger and bigger in near future. Although, there are various reasons for success of smart phone market, this research focused 4 reasons: first, development of mobile device, second, evolution of mobile content distribution, third, support of government system, fourth, success of Docomo i-mode and Apple i phone. Smart phone will grow up more rapidly. Smart phone eco-system will be more competitive in the world. In Korea, smart phone eco-system also will be very competitive. For success in the middle of this competitive environment, Korea should lead the competitive phase with development of ability of creation software and content, construction of various partnership and evolution of next generation technology and service.

The Impact of Consumer Characteristics Upon Trust and Purchase Intentions in B2C E-marketplaces (오픈마켓에서 개인특성이 신뢰 및 구매의도에 미치는 영향에 관한 실증연구)

  • Cho, Hwi-Hyung;Hong, Il-Yoo
    • Information Systems Review
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    • v.12 no.3
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    • pp.49-73
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    • 2010
  • The lack of customer satisfaction and trust remains a key barrier to electronic commerce. From the standpoint of online merchants, it is critical to build consumer trust by lessening sources of apprehensions and uneasiness associated with online transactions. This paper explores the relationships between customer satisfaction and intermediary's trustworthiness factors in B2C e-marketplaces. It also aims at examining the effects of consumer characteristics, including propensity to trust and Internet shopping self-efficacy, upon trust and purchase intentions. To meet the research objectives, an empirical study has been conducted by surveying 223 active e-marketplace buyers in Korea. The findings of the present research indicate that customer satisfaction positively affects all the three attributes of trustworthiness (i.e., competence, benevolence, and integrity), and more specifically it has a quite strong association with benevolence. In addition, propensity to trust has no significant influence on trust or purchasing intentions, and only affects benevolence and integrity with no direct effect on competence. Finally, Internet shopping self-efficacy was found to affect both trust and purchasing intentions, suggesting that e-marketplaces seek an online strategy designed to strengthen loyalty for customers with high self-efficacy, while they use a strategy to improve the usability and usefulness of their website to attract customers with low self-efficacy. The paper concludes with implications and directions for future research.