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Study on the global distribution of far-ultraviolet emission in our Galaxy

  • Jo, Young-Soo;Seon, Kwang-Il;Min, Kyoung-Wook;Edelstein, Jerry
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.52.1-52.1
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    • 2015
  • FIMS/SPEAR is a dual-channel far-ultraviolet imaging spectrograph on board the Korean microsatellite STSAT-1, which was launched on 2003 September 27. The primary mission goal of FIMS was to conduct a survey of diffuse far UV emissions in our Galaxy. For this purpose, FIMS completed a survey of about 84% of the sky during its operation of a year and a half. The present study aims to analyze this survey data made in the far UV wavelengths to understand the global evolution of our Galaxy. The far UV wavelength band is known to contain important cooling lines of hot gas: hence, the study will show how the hot gas in our Galaxy, produced by stellar winds and supernova explosion, evolves globally to cool down and become mixed with ambient cooler medium. One of the main findings from previous analyses of the FIMS data is that molecular hydrogen exists ubiquitously in our Galaxy. This discovery leads to another important scientific question: how is molecular hydrogen distributed in our Galaxy and how does it affect globally the evolution of our Galaxy as a cold component? Hence, the present study will cover both the hot and cold components of the ISM, which will also provide the opportunity to investigate the interactions between the two.

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Comparison of Code Generation Tools from Formal Specification of Security Function (정형명세 보안기능의 코드생성 도구 비교)

  • 유희준;김일곤;최진영;김상호;노병규
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.04a
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    • pp.829-831
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    • 2002
  • 최근 들어 보안에 대한 관심이 높아지고 있으며, 많은 보안 관련 프로그램이 사용되고 있는 상황이다. 하지만 안전성을 예측하기 어려운 보안 기능을 완벽하게 구현하기 위해서 현재의 테스팅 방법론만으로는 완전성을 보장할 수 없으므로 보다 안전한 보안 기능을 구현하기 위해서 정형명세 방법은 반드시 필요하다. 또한 실제로 시스템들이 개발되는 과정에 있어서 설계될 당시와는 달리 결함을 가질 수 있다. 시스템에 대한 명세가 정확하다 하더라도 개발자인 사람의 개입으로 인해서 개발하는 도중에 명세와 다른 결과를 초래하여 결함이 발생할 수 있다. 이러한 결함은 개발자나 사용자에 의해 쉽게 발견되기 어렵다. 만일 보안 시스템이 알져지지 않은 결함이 있다면 비밀 정보가 쉽게 누설될 수 있다는 큰 문제가 발생할 수 있다. 통신망을 사용하는 인구의 확대와 더불어 다양한 형태의 통신 서비스가 제공됨에 따라 시스템의 특성이 복잡해지고 불법적인 자료 접근의 위험도 많이 노출되고 있다. 따라서 명확한 정형명세 보안기능으로부터 자동 코드 생성은 반드시 필요하다. 본 논문에서는 여러 정형 도구를 사용해서 보안기능에 대한 정형명세를 작성한 후에 소스코드 생성한 후, 정형명세를 이용하여 설계 및 구현한 프로그램에 대한 명세와 소스코드간 일치성 검토 방법을 개발하여, 정형명세를 통해 생성된 보안기능 소스코드의 보안성 측면과 성능적 측면의 Teade-Off 분석하는 것이다. 논문에서는 인증 관련 보안 기능인 S/KRY에 대해서 4개(STATEMATE MAGMUM, Rational Rose 98, SPEAR, VDM-SL)의 정형도구를 사용하여 명세 후, 소스 코드를 생성하여 생성된 각 코드에 대하여 비교하였으며, 현재 상용화 되어있는 Bellcore 의 S/KEY 시스템과의 비교를 수행하였다. 분석에서는 제품의 효율성뿐만 아니라 보안성을 중요하게 생각하였으며, 앞으로 보안 관련 소프트웨어 개발에 사용될 수 있는 도구들이 가이드 라인에 대한 정보를 제공한다.

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Occurrence of a Spear Squid, Heterololigo bleekeri (Keferstein, 1866) from Korea (화살꼴뚜기 Heterololigo bleekeri (Keferstein, 1866) 의 국내출현)

  • Kim, Yeonghye;Lee, Hae Won;Chun, Young-Yull;Kang, Hyunjung
    • The Korean Journal of Malacology
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    • v.28 no.3
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    • pp.255-258
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    • 2012
  • Forty four specimens (22.5-34.2 cm ML) of Heterololigo bleekeri were collected around Dokdo, East Sea on March 1, 2012. It was identified as H. bleekeri based on the following combination of morphological character: mantle very elongate; fin large, thick, length two-thirds of mantle length; arms very short and small in relation to body size, are formula III>II>IV>I.

The distribution of the molecular hydrogen in the Milky way

  • Jo, Young-Soo;Seon, Kwang-Il;Min, Kyoung-wook
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.2
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    • pp.40.1-40.1
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    • 2016
  • We present the far-ultraviolet fluorescent molecular hydrogen ($H_2$) emission map observed with FIMS/SPEAR for ~76% of the sky. The fluorescent $H_2$ emission is found to be saturated by strong dust extinction at the optically thick, Galactic plane region. However, the extinction-corrected intensity of fluorescent $H_2$ emission is found to have strong linear correlations with the well-known tracers of the cold interstellar medium, such as the E(B-V) color excess, neutral hydrogen column density N(HI), $H{\alpha}$ emission, and CO $J=1{\rightarrow}0$ emission. The all-sky molecular hydrogen column density map is also obtained using a photodissociation region model. We also derive the gas-to-dust ratio, hydrogen molecular fraction ($f_{H2}$), and $CO-to-H_2$ conversion factor ($X_{CO}$) of the diffuse interstellar medium. The gas-to-dust ratio is consistent with the standard value $5.8{\times}10^{21}atoms\;cm^{-2}mag^{-1}$, and the $X_{CO}$ tends to increase with E(B-V), but converges to the Galactic mean value $1.8{\times}10^{20}cm^{-2}K^{-1}km^{-1}s$ at optically thick regions with E(B-V)>2.0.

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Unintentional and Involuntary Personal Information Leakage on Facebook from User Interactions

  • Lin, Po-Ching;Lin, Pei-Ying
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.7
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    • pp.3301-3318
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    • 2016
  • Online social networks (OSNs) have changed the way people communicate with each other. An OSN usually encourages the participants to provide personal information such as real names, birthdays and educational background to look for and establish friendships among them. Some users are unwilling to reveal personal information on their personal pages due to potential privacy concerns, but their friends may inadvertently reveal that. In this work, we investigate the possibility of leaking personal information on Facebook in an unintentional and involuntary manner. The revealed information may be useful to malicious users for social engineering and spear phishing. We design the inference methods to find birthdays and educational background of Facebook users based on the interactions among friends on Facebook pages and groups, and also leverage J-measure to find the inference rules. The inference improves the finding rate of birthdays from 71.2% to 87.0% with the accuracy of 92.0%, and that of educational background from 75.2% to 91.7% with the accuracy of 86.3%. We also suggest the sanitization strategies to avoid the private information leakage.

Influence of luminous jig to catching of squid jigging in the Korean waters (오징어 채낚기 낚시의 야광이 어획에 미치는 영향)

  • RYU, Kyung-Jin;KIM, Hyung-Seok
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.55 no.4
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    • pp.303-309
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    • 2019
  • This study identified the characteristics of squid jig in korea waters by investigating the effect of color and luminous performance of squid jig on the catch of squid and experimenting the result of jig according to green jig or white jig, and whether using luminous or not were tested in the sea to improve the jig of squid jigging. For this purpose, a total of 13 sea experiments were conducted using T/S No. 2 Galmaegi. As a result, 341 squids were caught. Among them, 221 squids were caught by green jig (64.8%), 64 squids were caught by white jig (18.8%), 41 squids were caught by green luminous jig (13.8%), and nine squids were caught by white luminous jig (2.6%). The green jig commonly used in jigging vessel was most effective, and luminous jig was less effective than that non-luminous jig. The squids caught were Japanese flying squid (Todarodes pacificus), swordtip squid (Loligo edulis) and spear squid (Loligo bleekeri), and no significant characteristics were found according to the color of jig and the presence of luminous.

Bright stars observed by FIMS/SPEAR

  • Jo, Young-Soo;Seon, Kwang-Il;Min, Kyoung-Wook;Choi, Yeon-Ju;Lim, Tae-Ho;Lim, Yeo-Myeong;Edelstein, Jerry;Han, Wonyong
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.44.1-44.1
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    • 2016
  • In this paper, we present a catalogue of the spectra of bright stars observed during the sky survey using the Far-Ultraviolet Imaging Spectrograph (FIMS), which was designed primarily to observe diffuse emissions. By carefully eliminating the contamination from the diffuse background, we obtain the spectra of 70 bright stars observed for the first time with a spectral resolution of $2-3{\AA}$ over the wavelength of $1370-1710{\AA}$. The far-ultraviolet spectra of an additional 139 stars are also extracted with a better spectral resolution and/or higher reliability than those of the previous observations. The stellar spectral type of the stars presented in the catalogue spans from O9 to A3. The method of spectral extraction of the bright stars is validated by comparing the spectra of 323 stars with those of the International Ultraviolet Explorer (IUE) observations.

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Comparative assessment of seismic rehabilitation techniques on a full scale 3-story RC moment frame structure

  • Di Ludovico, M.;Balsamo, A.;Prota, A.;Manfredi, G.
    • Structural Engineering and Mechanics
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    • v.28 no.6
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    • pp.727-747
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    • 2008
  • In the framework of the SPEAR (Seismic PErformance Assessment and Rehabilitation) research Project, an under-designed three storey RC frame structure, designed to sustain only gravity loads, was subjected, in three different configurations 'as-built', Fiber Reinforced Polymer (FRP) retrofitted and rehabilitated by reinforced concrete (RC) jacketing, to a series of bi-directional pseudodynamic (PsD) tests under different values of peak ground acceleration (PGA) (from a minimum of 0.20g to a maximum of 0.30g). The seismic deficiencies exhibited by the 'as-built' structure after the test at PGA level of 0.20g were confirmed by a post - test assessment of the structural seismic capacity performed by a nonlinear static pushover analysis implemented on the structure lumped plasticity model. To improve the seismic performance of the 'as-built' structure', two rehabilitation interventions by using either FRP laminates or RC jacketing were designed. Assumptions for the analytical modeling, design criteria and calculation procedures along with local and global intervention measures and their installation details are herein presented and discussed. Nonlinear static pushover analyses for the assessment of the theoretical seismic capacity of the structure in each retrofitted configuration were performed and compared with the experimental outcomes.

Displacement-recovery-capacity of superelastic SMA fibers reinforced cementitious materials

  • Choi, Eunsoo;Mohammadzadeh, Behzad;Hwang, Jin-Ha;Lee, Jong-Han
    • Smart Structures and Systems
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    • v.24 no.2
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    • pp.157-171
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    • 2019
  • This study investigated the effects of the geometric parameters of superelastic shape memory alloy (SE SMA) fibers on the pullout displacement recovering and self-healing capacity of reinforced cementitious composites. Three diameters of 0.5, 0.7 and 1.0 mm and two different crimped lengths of 5.0 and 10.0 mm were considered. To provide best anchoring action and high bond between fiber and cement mortar, the fibers were crimped at the end to create spear-head shape. The single fiber cement-based specimens were manufactured with the cement mortar of a compressive strength of 84 MPa with the square shape at the top and a dog-bone shape at the bottom. The embedded length of each fiber was 15 mm. The pullout test was performed with displacement control to obtain monotonic or hysteretic behaviors. The results showed that pullout displacements were recovered after fibers slipped and stuck in the specimen. The specimens with fiber of larger diameter showed better displacement recovering capacity. The flag-shaped behavior was observed for all specimens, and those with fiber of 1.0 mm diameter showed the clearest one. It was observed that the length of fiber anchorage did not have a significant effect on the displacement recovery, pullout resistance and self-healing capacity.

A Study on limit of Policeman's Exertion in Police Questioning (불심검문시 경찰관의 유형력행사의 한계)

  • Yoo, In Chang
    • Journal of Digital Convergence
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    • v.10 no.10
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    • pp.229-235
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    • 2012
  • Police questioning is police measure for acquiring information or inquiring an identification without questionee's will in order to accomplish the goal under the Police Act. However, like spear and shield, it has its own inherent limits between both sides of public power and human right and has stirred an hot issue in our society for longtime. The core problem is whether policeman can force a questionee stop when the questionee refuses policeman's stop requirement, the first step for police questioning. Some opinions argue that police questioning has somewhat effects on crime prevention and suspect arrest but people still have inconvenience and refusal from experiences of reckless police questioning in the past. Because of this, the police needs to recover people's trust on police questioning. In order to do so, in case of police questioning, human right should be superior to crime prevention or suspect arrest. This is the time's call. So when there is a police questioning, policeman's exertion of it on the questionee who refuse it should be conducted under strict conditions.