• Title/Summary/Keyword: Coverage factor (k)

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Analysis of the Lower Extremity Reconstruction with Free Tissue Transfer in Recent 5 Years (최근 5년간 유리 피판술을 이용한 하지재건의 분석)

  • Baek, Seong-Jun;Heo, Chan-Yeong;Oh, Kap-Sung
    • Archives of Reconstructive Microsurgery
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    • v.8 no.2
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    • pp.130-138
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    • 1999
  • The lower extremity injuries are extremely increasing with the development of industrial & transportational technology. For the lower extremity injuries that result from high-energy forces, particularly those in which soft tissue and large segments of bone have been destroyed and there is some degree of vascular compromise, the problems in reconstruction are major and more complex. In such cases local muscle coverage is probably unsuccessful, because adjacent muscles are destroyed much more than one can initially expect. Reconstruction of the lower extremity has been planned by dividing the lower leg into three parts traditionally The flaps available in each of the three parts are gastrocnemius flap for proximal one third, soleus flap for middle one third and free flap transfer for lower one third. Microvascular surgery can provide the necessary soft tissue coverage from the remote donnor area by free flap transfer into the defect. Correct selection of the appropriate recipient vessels is difficult and remains the most important factor in successful free flap transfer. Vascular anastomosis to recipient vessels distal to the zone of injury has been advocated and retrograde flow flaps are well established in island flaps. Retrograde flow anastomosis could not interrupt the major blood vessels which were essential for survival of the distal limb, the compromise of fracture or wound healing might be prevented. During 5 years, from March 1993 to Feb. 1998, we have done 68 free flap transfers in 61 patients to reconstruct the lower extremity. From analysis of the cases, we concluded that for the reconstruction of the lower extremity, free flap transfer yields a more esthetic and functional results.

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Multi-Hop Clock Synchronization Based on Robust Reference Node Selection for Ship Ad-Hoc Network

  • Su, Xin;Hui, Bing;Chang, KyungHi
    • Journal of Communications and Networks
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    • v.18 no.1
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    • pp.65-74
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    • 2016
  • Ship ad-hoc network (SANET) extends the coverage of the maritime communication among ships with the reduced cost. To fulfill the growing demands of real-time services, the SANET requires an efficient clock time synchronization algorithm which has not been carefully investigated under the ad-hoc maritime environment. This is mainly because the conventional algorithms only suggest to decrease the beacon collision probability that diminishes the clock drift among the units. However, the SANET is a very large-scale network in terms of geographic scope, e.g., with 100 km coverage. The key factor to affect the synchronization performance is the signal propagation delay, which has not being carefully considered in the existing algorithms. Therefore, it requires a robust multi-hop synchronization algorithm to support the communication among hundreds of the ships under the maritime environment. The proposed algorithm has to face and overcome several challenges, i.e., physical clock, e.g., coordinated universal time (UTC)/global positioning system (GPS) unavailable due to the atrocious weather, network link stability, and large propagation delay in the SANET. In this paper, we propose a logical clock synchronization algorithm with multi-hop function for the SANET, namely multi-hop clock synchronization for SANET (MCSS). It works in an ad-hoc manner in case of no UTC/GPS being available, and the multi-hop function makes sure the link stability of the network. For the proposed MCSS, the synchronization time reference nodes (STRNs) are efficiently selected by considering the propagation delay, and the beacon collision can be decreased by the combination of adaptive timing synchronization procedure (ATSP) with the proposed STRN selection procedure. Based on the simulation results, we finalize the multi-hop frame structure of the SANET by considering the clock synchronization, where the physical layer parameters are contrived to meet the requirements of target applications.

Normalized characteristics of the photonic bandgaps in two-dimensional photonic crystals with a hexagonal lattice by FDID simulation (FDTD 시뮬레이션을 이용한 육방정계형 2차원 광자결정에서의 광자밴드갭 특성 정규화)

  • Yeo, Jong-Bin;Lee, Hyun-Yong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.38-38
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    • 2009
  • Characteristics of the photonic bandgaps (PBGs) in two-dimensional photonic crystals (2D PCs) with a hexagonal lattice have theoretically studied using a finite difference time domain (FDTD) simulation. In this research, we propose a concept of optical coverage ratio (OCR) as a new structural parameter to determine the PBGs for E-polarized light. The OCR is an optically compensated filling factor. It is possible to normalize the PBGs of 2D PCs by introducing the OCR.

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Planting of Urban Environmental Forest and Community Planting Area (도시환경림 및 군락식재지의 배식 기법 연구)

  • Cho, Woo;Lee, Kuong-Jae
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.1
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    • pp.70-82
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    • 1998
  • The purpose of this study was to propose the community planting method through analyzing the plant community structure of three green space types and the relationship of vegetation and wild bird inhabitation of urban environmental forest in Seoul, Korea. The results from this study showed that the vegetation stratification, coverage, and species diversity were closely related to the wild bird inhabitation. In addition, the environmental forest in study site was analyzed as a negative factor that may decrease the biodiversity. Therefore the ecological structure and environmental condition must be considered in order to improve the quality of environmental forest. Based on results in three green space types, the planting species, density and species size for proper community planting were proposed in this study. The ecological niche relationships among sixteen selected species were also presented. The results will be provided as an valueable output for the completed community planting of urban green space in the central region, Korea.

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A Study on FMEDA Process for SIL Certification : A Case Study of a Flame Scanner (SIL 인증을 위한 FMEDA 프로세스 연구 : 화염검출기 사례를 중심으로)

  • Kim, Sung Kyu;Kim, Yong Soo
    • IE interfaces
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    • v.25 no.4
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    • pp.422-430
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    • 2012
  • In this article, we introduced the estimation method by 'Safety Integrity Level'(SIL) for the criterion of safety assurance and performed a case study on a flame scanner. SIL requires probabilistic evaluation of each set of equipment used to reduce risk in a safety related system. FMEDA(Failure Modes, Effects and Diagnostic Analysis) method is widely used to evaluate the safety levels and provides information on the failure rates and failure mode distributions necessary to calculate a diagnostic coverage factor for a part or a component. Basically, two parameters resulting from FMEDA are used for SIL classification of the device : SFF(Safe Failure Fraction) and PFD(Probability of Failure on Demand). In this case study, it is concluded that the flame scanner is designed to fulfill the condition of SIL 3 in the aspect of SFF and PFD.

Base Station Placement for Wireless Sensor Network Positioning System via Lexicographical Stratified Programming

  • Yan, Jun;Yu, Kegen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.11
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    • pp.4453-4468
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    • 2015
  • This paper investigates optimization-based base station (BS) placement. An optimization model is defined and the BS placement problem is transformed to a lexicographical stratified programming (LSP) model for a given trajectory, according to different accuracy requirements. The feasible region for BS deployment is obtained from the positioning system requirement, which is also solved with signal coverage problem in BS placement. The LSP mathematical model is formulated with the average geometric dilution of precision (GDOP) as the criterion. To achieve an optimization solution, a tolerant factor based complete stratified series approach and grid searching method are utilized to obtain the possible optimal BS placement. Because of the LSP model utilization, the proposed algorithm has wider application scenarios with different accuracy requirements over different trajectory segments. Simulation results demonstrate that the proposed algorithm has better BS placement result than existing approaches for a given trajectory.

Seroprevalence of Measles Antibody and its Attributable Factors in Elementary Students of Routine 2-dose Schedule Era with Vaccination Record (예방접종력이 있는 초등학생의 홍역 항체 양성률 및 기여 요인)

  • Lim, Hyun-Sul;Goh, Un-Yeong;Yang, Byung-Guk;Kim, Young-Taek;Lee, Jong-Koo;Bae, Geun-Ryang
    • Journal of Preventive Medicine and Public Health
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    • v.38 no.4
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    • pp.431-436
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    • 2005
  • Objectives : We investigated the seroprevalence of the measles antibody and its at tributable factors for the students who underwent routine 2-dose Schedule Era. Methods : The subjects were 996 students of the national measles seroepidemiologic study in December 2000 who had vaccination records. We conducted a questionnaire survey and we performed serologic testing for the measlesspecific IgG by using an enzyme linked immunosorbent assay. Results : The coverage for the first dose of the MMR vaccination at 12-15 months of age was 95.1% and the coverage for the second dose of MMR at 4-6 years of age was 35.0%. The proportion of subjects undergoing 2-dosesof MMR dec reased as the age of the subjects increased. The seropositive rate of the measles antibody was significantly high in the second dose vaccinees (93.5% in the second dose group, 84.7% in the non-second dose group, p<0.001) and it was 72.0% in the 0-dose group, 85.4% in the 1-dose group and 93.7% in the 2-dose group (p<0.001). Two point eight percent of the subjects had a past history of measles infection. On the multiple logistic regression analysis, the first and second dose (odds ratio, 8.54; 95% CI.=3.05-23.91), the first dose (odds ratio, 3.06; 95% CI.=1.20-7.81) and the outbreak in the year 2000 (odds ratio, 1.89; 95% CI.=1.24-2.88) were the significant factors for the seropositivity. Conclusions : Maintaining high coverage with a 2-dose vaccination program would be the decisive factor to prevent an outbreak of measles and to eliminate measles in Korea.

A Study on the School Uniform Pants Sizing System depending on Lower Body Type for Highschool Girls (여고생 하반신 체형특성에 따른 교복바지 치수설정에 관한 연구)

  • Choi, Eun-Hee;Do, Wol-Hee
    • Fashion & Textile Research Journal
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    • v.14 no.5
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    • pp.834-845
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    • 2012
  • This study was conducted to provide basic information on developing highschool-uniform pants with more suitable fit and to suggest a sizing system for highschool girls' uniform pants that adequately reflects their body figures. To understand the features of high school girls' lower body type, the body measurement values of 833 girls from 16~18 years of age based on Size Korea(2010) were analyzed statistically. For the classification of lower body type for high school girls, a factor analysis and cluster analysis were conducted. The collected data were processed with the programs SPSS 18.0 for windows. The results in this study are follows: The lower body types for high school girls were divided into 3 groups. Body Type A is average stature but the biggest circumference, Type B is the biggest stature and the medium body type, Type C is the smallest stature and skeleton structure. KS size intervals were used for frequency distribution of height and waist for the lower body. Sizing system of the uniform company and frequency distribution of sizes were compared. Using the two-way distribution of highschool girls' waist circumference and hip circumference, sizing system considering body type distribution and high frequency distribution section of sizes was suggested. This study established new sizing system depending on lower body fixed as 26 number of sizes. The most suitable standard is fixed as 12 number of sizes ; 64-88, 64-91, 67-88, 67-91, 67-94, 70-91, 70-94, 70-97, 73-94, 73-97, 76-97, 76-100. The coverage is also calculated. And the coverage of new standard was 63.5%. The continuous study on the uniform pants sizing system of the obesity types is required.

Relationship between Experience of Requesting Verification of Healthcare Benefit Coverage and Patients' Trust in Physicians and Hospitals (진료비 확인 민원신청 경험과 의사 및 의료기관에 대한 신뢰도와의 관련성)

  • Hahm, Myung-Il;Min, Insoon
    • Health Policy and Management
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    • v.23 no.3
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    • pp.289-300
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    • 2013
  • Background: Patients' trust in their physicians or hospitals is important to guarantee the effectiveness of care and to encourage revisits. This study aimed to identify the relationship between the experience of requesting verification of healthcare benefit coverage via the Health Insurance Review Agency (HIRA) and patients' trust in their physicians or hospitals. Methods: For this population-based study, 800 adult respondents aged 20 to 65 years were recruited using random sampling and telephone surveys. Respondents were divided into two groups: 1) 400 people had experience in requesting the HIRA verification service for the purpose of confirmation of whether the costs they paid were appropriate among metropolitan habitants, and 2) 400 people comprised members of the public who had no experience requesting the verification service. Results: Experience with requesting verification services was likely to lower the patients' trust in medical institutions, but not in their physicians (p<0.05). In addition, patients who were satisfied with their physicians and hospitals were more likely to trust the physicians and hospitals than dissatisfied patients. Conclusion: Patients' trust might be an important factor influencing hospital success. Patients' trust in medical suppliers, such as physicians and hospitals, encourages a positive relationship between medical suppliers and patients. Therefore, medical suppliers must provide appropriate care to patients to improve patients' trust in them.

A Multi-Antenna Mobile Measurement System for DTV Coverage Measurement (DTV 커버리지 측정을 위한 다중 안테나 이동측정시스템)

  • Jeong, Young-Seok;Yang, Hae-Sool
    • Journal of Digital Convergence
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    • v.11 no.11
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    • pp.85-94
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    • 2013
  • This paper presents a novel mobile measurement system with multi antennas which enable mobile measurement as well as fixed measurement with telescope mast. Proposed system installed 4 omni directional antennas for the space diversity process and one directional log periodic antenna for the simultaneous conventional fixed measurement. Whole antenna systems are connected to the custom DTV channel analyzers with Ethernet networks respectively and processed by the main controller to calculate real time average receive levels. To prove the performance of proposed system, the typical receive models are categorized as 3 area types - open area, building area and house area, and then intensive field tests were performed through mobile and fixed measurement phases. With these measurement data, the relationships between mobile and fixed measurement are analyzed, and the concept of compensation factor is proposed to assume the average receive level of signal. The field test is fulfilled as a co-work with public broadcasters and the proposed system is applied to the intensive coverage measurement projects for metropolitan areas by the korean government agencies.