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Trends of Disaster Management Research (행정학에서 재난관리분야의 학문적 연구경향)

  • Ahn, Hye-Won;Ryu, Sang-Il
    • The Journal of the Korea Contents Association
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    • v.7 no.10
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    • pp.183-190
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    • 2007
  • This study aim is to investigate disaster management actual in field of public administration and establish object of disaster management study by surveying the trends of disaster management for development of disaster management. This study has examined the trends in researches on disaster management that have been done so far First, their changes have been investigated by years and it was found out that the studies on disaster management accounted for 81.8% after the year of 2000. Second case studies accounted for 47.7%, with respect to the method for research which means researchers lay emphasis on case studies. Third, the studies that aim to suggest policy alternatives were found the highest with 79.5%, in regard of research objectives, an the studies on verification theories with 13.6%, which means that more efforts need to be made on theorization and verification continuously to lay the groundwork for studying disaster management. Fourth the studies have been examined by type of disaster and it was found out that since 2001 the studies on social disasters and comprehensive studies on social, man-made and natural disasters have increased by 27.3% and 50% respectively. Fifth, studies have been examined by administrative units and it was found out that the studies on central government local government, private sector and NGO's disaster management accounted for the highest percentage with 50%. Lastly, the studies on preliminary strategies(mitigation & prepaedness) and post-strategies (response & recovery) accounted for the highest percentage, 56.8%, with respect to disaster management steps, and it was shown that studies are being made preponderantly on post-strategies.

A Systematic Literature Review on SaaS: Identifying Research Trend in Korean Academia (SaaS관련 체계적인 연구문헌 분석: 국내 학술 경향 연구)

  • Lee, Hye-Jung;Lee, Jung-Woo;Cho, Cheul-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.6
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    • pp.2729-2738
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    • 2012
  • The purpose of this study is, to analyze the recent trend of studies on SaaS(Software as a Service) in Korea and to suggest a direction for the future research. For this purpose, the relevant literatures published in Korea Citation Index and literatures presented in conferences were gathered. Among these literatures, total of 39 samples were selected and used in the systematic literature review. The result shows that the application of SaaS in actual operations of industries are widely proliferated. However, the studies on SaaS generally lacks in its number and types. For example, studies so far are only on field of engineering and technology. Considering the fact that SaaS is moving towards the service orientation, studies on SaaS should develop in the fields of policy, business, individual and society sides of studies. In addition, the existing studies uses different concepts of relations between SaaS and ASP(Application Service Provider), as well as, different definitions of SaaS. Lastly, our research analyzed the problems of utilization of SaaS and found that, the quality, performance and security are presented as the core of the problems.

Analysis of Radio Propagation Environment in Busan Area for DTV Service (디지털 TV서비스를 위한 부산지역 전파환경 분석)

  • Sung Tae-Kyung;Weon Young-Su;Cho Hyung-Rae;Kim Ki-Moon
    • Journal of Navigation and Port Research
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    • v.28 no.10 s.96
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    • pp.869-874
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    • 2004
  • Digital TV broadcasting's resolution or tone quality is very excellent than analog broadcasting and has many advantages including various multimedia functions such as home shopping, home banking, internet search, telecommuting, VOD, etc. In this study, it is essential to analyze the regional electromagnetic environment before Digital TV broadcasting, and therefore we analyzed Busan area's limitation using ETRI propagation model. For maintaining high-quality Digital TV signals, we measure electric field intensity wide and far in Busan including mountains area and high-rise buildings. Generally, it has lower value by a standard ETRI propagation model than simulated value about standard model, but distribution pattern are similar with it. Compared theoretical values with the measured results, they have similar values for flat area but very different values for crowded city area and mountains area So we conclude that ETRI propagation model and theoretical model are not suitable for Busan in a free space.

The Development Method of IFC Extension Elements using Work Breakdown Structure in River Fields (작업분류체계를 활용한 하천분야 IFC 확장 개발방안)

  • Won, Jisun;Shin, Jaeyoung;Moon, Hyoun-Seok;Ju, Ki-Beom
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.4
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    • pp.77-84
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    • 2018
  • As the application of BIM (Building Information Modeling) to the civil sector has become practical, and mandatory for road projects, the standardization, development of systems, etc. for the application and operation of BIM are required. In particular, it is important to develop BIM data standards for producing, sharing and managing the lifecycle data of civil facilities because they are commonly national public facilities. The BIM data standards have been developed by utilizing or extending IFC (Industry Foundation Classes), which is an international standard, but schema extensions of river facilities has not been developed thus far. This study proposes an approach to an IFC extension for river facilities using the WBS (Work Breakdown Structure) as a fundamental study for IFC-based schema extension in the river field. For this purpose, the research was carried out as follows. First, the IFC extension development method was selected to represent the river facilities by analyzing the existing IFC structure and previous research cases for the IFC extension. Second, extended elements of the river facilities were identified through an analysis of the WBS and classified according to the high-level structure of the IFC schema. Third, the classified elements were arranged based on the IFC hierarchy and the IFC schema extension for river facilities was established. Based on the suggested extension method of IFC schema, this study developed the schema by defining the element components and parts of river facilities, such as distribution flow elements and deriving their detailed types and properties.

Random Forest Method and Simulation-based Effect Analysis for Real-time Target Re-designation in Missile Flight (유도탄의 실시간 표적 재지정을 위한 랜덤 포레스트 기법과 시뮬레이션 기반 효과 분석)

  • Lee, Han-Kang;Jang, Jae-Yeon;Ahn, Jae-Min;Kim, Chang-Ouk
    • Journal of the Korea Society for Simulation
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    • v.27 no.2
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    • pp.35-48
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    • 2018
  • The study of air defense against North Korean tactical ballistic missiles (TBM) should consider the rapidly changing battlefield environment. The study for target re-designation for intercept missiles enables effective operation of friendly defensive assets as well as responses to dynamic battlefield. The researches that have been conducted so far do not represent real-time dynamic battlefield situation because the hit probability for the TBM, which plays an important role in the decision making process, is fixed. Therefore, this study proposes a target re-designation algorithm that makes decision based on hit probability which considers real-time field environment. The proposed method contains a trajectory prediction model that predicts the expected trajectory of the TBM from the current position and velocity information by using random forest and moving window. The predicted hit probability can be calculated through the trajectory prediction model and the simulator of the intercept missile, and the calculated hit probability becomes the decision criterion of the target re-designation algorithm for the missile. In the experiment, the validity of the methodology used in the TBM trajectory prediction model was verified and the superiority of using the hit probability through the proposed model in the target re-designation decision making process was validated.

Fabrication and analysis of $1.3\mum$ spot-size-converter integrated laser diodes (광모드변환기가 집적된 $1.3\mum$ SC-FP-LD 제작 및 특성 해석)

  • 심종인
    • Korean Journal of Optics and Photonics
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    • v.11 no.4
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    • pp.271-278
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    • 2000
  • We have fabricated and analyzed the lasing characteristics of 1.3$\mu\textrm{m}$ Spot-Size-Converter (SSC) integrated Fabry-Perot (FP) laser diodes, which are very promising light sources for optical subscriber networks. SSC-LDs has been developed by BIB (buttjoint-built-in) coupling and selective MOVPE growth. High-performances were achieved such as the slope efficiency from the SSC facet of 0.23-0.32 mW/mA, the full-width at the half maximum of the far-field pattern (FFP) of 9.5$^{\circ}$~12.3$^{\circ}$, the alignment tolerances of $\pm$2.3$\mu\textrm{m}$ and $\pm$2.5$\mu\textrm{m}$ within the extra-coupling loss of 1 dB for the vertical and parallel directions, respectively. These experimental results were compared to theoretical ones in order to clarify the operational problems and give a good design direction of the fabricated SSC-LDs. It was revealed that an asymmetric output power from the facets, an irrelevancy of FFP and the waveguide structure around SSC facet region, and a poor temperature characteristics were originated from the scattering in the BIB and SSC sections and SHB effect in the active section for the first time.t time.

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A Dynamic Analysis of the Women's Labor Market Transition: With a Focus on the Relationship between Productive and Reproductive Labor (여성의 생산노동과 재생산노동의 상호연관성이 취업에 미치는 영향에 관한 경험적 연구)

  • 이재열
    • Korea journal of population studies
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    • v.19 no.1
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    • pp.5-44
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    • 1996
  • Wornen's lahor market participation as well as the policy concern for wider utilization of married women, have continuously grown up. However, research efforts on the determinants of women's labor market participation, in the context of the relationship hetween life courses and active entry into lahor market, has been far behind the growing interest in this field. This study has conducted an event histoiry analysis of women's labor market transition utilizing personal occupational history data collected by the Korea Institute for Women's Development in 1991. The analysis is divided into tow parts: First part introduces logit regression to analyze the determinants of women's labor market participation and exit. The second part employs Cox regression to see the variation of transition rate between employment and non-employment. The result shows that there is a wide variation in women's labor market participation according to age, cohort, and family formation. Special note is needed for the significantly negative effect of marriage and child birth on labor market participation. The transition pattern of lower class women with less education fits well to the prediction of neo-classical economics; but the tendency of highly educated women's regression to non-employment reveals the strong influence of the unfavorable labor market structure, which can be better explained by the neo-structuralist perspective. There is a strong trade-off between productive and reproductive labor of women, which can only be corrected by strong policy implementation, such as extended child care facilities, abolition of discriminatory employment practices, and expansion of flexible part-time employment.

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Analysis of Blasting Vibration at the Irregular Layered Structure Ground (불규칙한 층상구조 지반에서의 발파진동 분석)

  • Kim, Seung Hyun;Lee, Dong Wook
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.5
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    • pp.891-901
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    • 2016
  • By comparing test blasting data experimented in three layered-structure polymorphic grounds to a geological profile, influence of blast vibration with respect to uncontrollable ground characteristics was analyzed. Inefficient blast have been performed without sufficient verifications or confirmations because insufficiencies with regard to experiments and data of blasting engineering on the layered structures to be irregularly repeated clinker layer consisted of volcanic clastic zones. It is difficult to quantify N values of clinkers within test blasting region because they have diverse ranges, or coverages. An absolute value of attenuation coefficient N in a field, estimated by blasting vibration predictive equation (SRSD), are lesser than criteria of a design instruction, meaning that vibrations caused by blast can spread far away, and the vibrational characteristics of blasting test No.1, indicating relatively small values, inferred by the geological profile, pressures of gas by the explosion may be lost into a widely distributed clinker layers by penetrating holes resulted from blast into vicinity of clinker layers located in bottom of soft rock layers at the moment of blast. As a result, amounts of spalling rocks are decreased by almost half. Also, ranges of primary frequencies in the fields are identified as similar to those of natural frequency of typical structures.

PRELAMINATED FREE FLAP FOR THE RECONSTRUCTION OF MAXILLARY DEFECTS (전판상화 유리조직판을 이용한 상악결손 재건)

  • Kim, Ji-Youn;Pang, Kang-Mi;Park, Jong-Chul;Kim, Sung-Min;Myoung, Hoon;Kim, Myung-Jin;Lee, Jong-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.35 no.1
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    • pp.13-20
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    • 2009
  • Background In contrast to defects of the mandible and mouth floor region, in the defect of maxilla, the availability of firmly attached oral and nasal mucosal linings is needed. In addition to it, in consider of operation field, operating convenience, and esthetics, reconstruction using prelaminated flap is strongly recommended. Therefore we consider the prelaminated flap through the cases that is reconstructed using prelaminated forearm flap and prelaminated scapular flap. Patients and Methods From 2001 to 2008, in OMFS SNUDH, there were 6 cases that had reconstruction using prelaminated forearm free flap and other 3 cases that had reconstruction using prelaminated scapular flap of maxilla. The average age of patients that were reconstructed using prelaminated forearm free flap was 47.5 years, the average prelaminated period (after $1^{st}$ operation ${\sim}$ until $2^{nd}$ operation) was 51.8 days and the average follow-up period after $2^{nd}$ operation was 35.3 months. As well, the average age of patients that were reconstructed using prelaminated scapular free flap was 37 years, the average prelaminated period (after $1^{st}$ operation ${\sim}$ until $2^{nd}$ operation) was 57 days and the average follow-up period after $2^{nd}$ operation was 42.3 months. Results Except 1 case that were reconstructed using prelaminated scapular flap, we could get firmly attached oral and nasal stable skin(mucosal like) lining, more adequate thickness flap than any other flap and improved esthetic and functional results in the other 8 cases that were reconstructed using prelaminated flap. The complications of the prelaminated forearm flap cases were inconvenient swallowing, sputum, limitation of mouth opening and difficult mastication. It came from flap shrinkage of the flap in some aspect, as well as other combined operations such as mass resection or RND. The difficult point of the reconstruction of prelaminated scapular flap was the possibility of vascular damage at preparation of flap in $2^{nd}$ surgery. The damage could cause the failure of the prelaminated scapular flap. And the skin-lining of the prelaminated flap had limitations, so it is needed to study about the cultured oral epithelium-lining flap instead of the skin-lining flap. Conclusion We considered about advantages, complications and notable things of prelaminated flap through maxillary reconstruction cases using prelaminated forearm flap and prelaminated scapular flap so far. Furthermore, we should go on studying for functional reconstruction of prelaminated fasciomucosal flap using cultured oral epithelium.

An Analysis of Relationship between Industry Security Education and Capability: Case Centric on Insider Leakage (보안교육과 보안관리 역량의 상관관계 분석: 인가된 내부자 기밀유출사례를 중심으로)

  • Lee, Chi-Seok;Kim, Yanghoon
    • The Journal of Society for e-Business Studies
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    • v.20 no.2
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    • pp.27-36
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    • 2015
  • Current leakage of industrial technologies with revealing state secret against nation is gradually increasing and scope of the spill is diversified from technology-oriented leakage to new economic security sector like information and communication, electrical and electronic, defense industry, illegal export of strategic material, economic order disturbance by foreign country, infringement of intellectual property, etc. So the spill damage can affect not only leaked company but also national interests and entire domestic industry. According to statistics from National Industrial Security Center of National Intelligence Service, a major cause of technology leakage is not only by external things about hacking and malignant code, but internal leakage of former and current employees account for about 80%. And technology leakage due to temptation of money and personal interests followed by technology leakage of subcontractor is steadily increased. Most studies in the field of security have tended to focus on measuring security capability of company in order to prevent leakage core assets or developing measurement Indicators for management rather than security activities of the company members that is most important. Therefore, this study analyzes the effect of most underlying security education in security activities on security capabilities of enterprise. As a result, it indicates that security education have a positive(+) correlation with security capabilities.