• Title/Summary/Keyword: Center Loss

Search Result 3,755, Processing Time 0.033 seconds

A Study on the Marine Traffic Risk Assessment by using Ship Handling Simulator (선박조종 시뮬레이터를 이용한 해상교통 위험도 평가에 관한 연구)

  • Park, Young-Soo;Kim, Jong-Sung;Kim, Chol-Seong;Yong, Jeong-Jae;Lee, Hyong-Ki;Jeong, Eun-Seok
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.19 no.2
    • /
    • pp.138-144
    • /
    • 2013
  • Large and small marine accidents which are related to vessel's navigation are happening continuously and these maritime accidents have caused loss of lives and properties, and serious maritime environmental pollution damage. It is also true that maritime pollution damage is increasing due to these accidents, probability of growth of seaborne volume and complicated maritime traffic environment. Korea, recently, is developing an evaluation index which can assess sea risk through the evaluation of maritime traffic environment and provide danger and general information with relation to maritime traffic environment on target sea area to evaluate maritime traffic safety. In this paper, we intend to confirm the validity of maritime traffic safety on the basis of vessel navigator's risk consciousness and various sailing conditions by using the ship handling simulator. To confirm the validity of sailing vessel's maritime traffic safety, we use analysis of variance. By using analysis of variance, we analyze vessel navigator's characteristics, distance, speed and encounter type between vessels. Through multiple comparison of each factor's risk difference, we can confirm the change of numerical value of risk difference in statistical aspect.

Oxidation behavior of (Mo1-xWx)Si2 high-temperature heating elements (초고온용 발열체 (Mo1-xWx)Si2의 산화거동에 대한 연구)

  • Lee, Sung-Chul;Myung, Jae-ha;Kim, Yong-Nam;Jeon, Minseok;Lee, Dong-won;Oh, Jong-Min;Kim, Bae-Yeon
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.30 no.5
    • /
    • pp.200-207
    • /
    • 2020
  • MoSi2, (Mo1/2W1/2)Si2, and WSi2 powders were synthesized by self-propagating high-temperature synthesis (SHS) method. The synthesized powders were heat-treated at 500, 1,000, 1,200, 1,300, 1,400, 1,500 and 1,600℃ in ambient atmosphere. Oxidation of Mo-W silicide powder was found at low temperature of 500℃. XRD structure analysis and DTA/TG data showed that MoO3 was formed with 500℃ heat treatment for 1 hour, and that it was α-cristobalite phase that was formed with 1200℃ heat treatment, not α-quartz phase which is commonly found and stable at room temperature. Existence of W accelerated decomposition at both low and high temperature. Fully sintered MoSi2 and (Mo1/2W1/2)Si2 specimen did not show decomposition or weight loss by oxidation, with 1 hour heat treatment at either low or high temperature. Notably, it was difficult to sinter WSi2 because of oxidation reaction at low temperature.

Control Thresholds (CTs) of Imported Cabbage Worm (Artogeia rapae L.) for Chinese Cabbage in Korea (배추에 대한 배추흰나비(Artogeia rapae L.)의 요방제수준)

  • Kwon, Min;Kim, Ju-Il;Yoon, Young-Nam;Choi, June-Yeol
    • Korean journal of applied entomology
    • /
    • v.47 no.4
    • /
    • pp.401-405
    • /
    • 2008
  • This study was conducted to estimate the control thresholds (CTs) of imported cabbage worm, Artogeia rapae L., injuring Chinese cabbage. The second instar larvae of A. rapae were inoculated with five density levels on each Chinese cabbages transplanted three weeks earlier under greenhouse condition, and checked injury rates after allowing their feeding for one week and two weeks, respectively. The average leaf area consumed by single larvae was 657.7 $mm^2$ in plots inoculated at three weeks after transplanting (WAT) and 2495.8 $mm^2$ in plots at 6-WAT, respectively. In the field experiment, different numbers of A. rapae ranged from one to seven larvae were inoculated on 20 plants. The percent yield reduction (Y) of Chinese cabbage infested by different densities of A. rapae (X) for a three-week period was estimated by the following equation; (1) Y=1.764X-0.3049 ($R^2$=0.9901) in plots inoculated at 3-WAT; and (2) Y=1.0305X-0.2976 ($R^2$=0.9398) in plots inoculated at 6-WAT. Based on the relationships between the densities of A. rapae larvae and the yield index of Chinese cabbage, the number of second instar larvae which caused 5% loss of yield (gain threshold proposed by Japan), was estimated as 3.0 per 20 plants for the 3-WAT and 5.1 for the 6-WAT.

A Study on Design and Fabrication of High Isolation W-band MIMIC Single-balanced Mixer (높은 격리도 특성의 W-밴드용 MIMIC 단일 평형 주파수 혼합기의 설계 및 제작 연구)

  • Yi, Sang-Yong;Lee, Mun-Kyo;An, Dan;Lee, Bok-Hyung;Lim, Byeong-Ok;Rhee, Jin-Koo
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.44 no.11
    • /
    • pp.48-53
    • /
    • 2007
  • In this paper, a high LO-RF isolation W-band MIMIC single-balanced mixer was designed and fabricated using a branch line coupler and a ${\lambda}/4$ transmission line. The W-band MIMIC single-balanced mixer was designed using the $0.1\;{\mu}m$ InGaAs/InAlAs/GaAs Metamorphic HEMT diode. The fabricated MHEMT was obtained the cut-off frequency($f_T$) of 154 GHz and the maximum oscillation frequency($f_{max}$) of 454 GHz. The designed MIMIC single-balanced mixer was fabricated using $0.1\;{\mu}m$ MHEMT MIMIC process. From the measurement, the conversion loss of the single-balanced mixer was 12.8 dB at an LO power of 8.6 dBm. P1 dB(1 dB compression point) of input and output were 5 dBm and -8.9 dBm, respectively. The LO-RF isolations of single-balanced mixer was obtained 37.2 dB at 94 GHz. We obtained in this study a higher LO-RF isolation compared to some other balanced mixers in millimeter-wave frequencies.

A familial case of limb-girdle muscular dystrophy with CAV3 mutation

  • Lee, Seungbok;Jang, Sesong;Shim, Youngkyu;Kim, Woo Joong;Kim, Soo Yeon;Cho, Anna;Kim, Hunmin;Kim, Jong-Il;Lim, Byung Chan;Hwang, Hee;Choi, Jieun;Kim, Ki Joong;Chae, Jong Hee
    • Journal of Genetic Medicine
    • /
    • v.16 no.2
    • /
    • pp.67-70
    • /
    • 2019
  • Limb-girdle muscular dystrophy (LGMD) is a group of muscular dystrophies that has extremely heterogeneous clinical features and genetic background. The caveolin-3 gene (CAV3) is one of the causative genes. LGMD appears as a clinical continuum, from isolated skeletal muscle involvement to long QT syndrome. Here we report two patients without apparent muscle weakness in a family with CAV3 mutation. A 7-month-old Korean boy visited our muscle clinic because of an incidental finding of elevated serum creatine kinase (CK) concentration (680 IU/L, reference range, 20-270 IU/L) without clinical symptoms. The patient was born after an uneventful pregnancy and showed normal developmental milestones. He developed pseudohypertrophy of his calf muscle during the follow-up. We obtained a muscle biopsy at age 14 months, which showed size variations and degenerating/regenerating myofibers with endomysial fibrosis and immunohistochemical evidence of normal dystrophin. Under the impression of LGMD, we performed target panel sequencing and identified a heterozygous in-frame mutation of CAV3, c.307_312delGTGGTG (p.Val103_Val104del). Immunohistochemical staining of muscle indicated complete loss of caveolin-3 compared with normal control muscle, which supported the variant's pathogenicity. We performed segregation analysis and found that the patient's mother had the same variant with elevated serum CK level (972 IU/L). We report on autosomal dominant familial caveolinopathy caused by a pathogenic variant in CAV3, which was asymptomatic until the fourth decade. This case highlights the utility of next generation sequencing in the diagnosis of muscular dystrophies and the additive role of muscle biopsy to confirm the variants.

Efficacy of Single-Port Video-Assisted Thoracoscopic Surgery Lobectomy Compared with Triple-Port VATS by Propensity Score Matching

  • Song, Kyung Sub;Park, Chang Kwon;Kim, Jae Bum
    • Journal of Chest Surgery
    • /
    • v.50 no.5
    • /
    • pp.339-345
    • /
    • 2017
  • Background: In recent years, single-port video-assisted thoracoscopic surgery (VATS) for lobectomy in non-small cell lung cancer (NSCLC) patients has become increasingly common. The objective of this study was to compare the feasibility and safety of single-port and triple-port VATS lobectomy. Methods: A total of 73 patients with NSCLC who underwent VATS lobectomy from December 2011 to August 2016 were retrospectively reviewed, including 47 in the triple-port group and 26 in the single-port group. Statistical analysis was performed after propensity score matching. Patients were matched on a 1-to-1 basis. Results: Operative time and intraoperative blood loss in the triple-port group and the single-port group were similar ($189.4{\pm}50.8minutes$ vs. $205.4{\pm}50.6minutes$, p=0.259; $286.5{\pm}531.0mL$ vs. $314.6{\pm}513.1mL$, p=0.813). There were no cases of morbidity or mortality. No significant differences in complications or the total number of dissected lymph nodes were found between the 2 groups. In the single-port group, more mediastinal lymph nodes were dissected than in the triple-port group ($1.7{\pm}0.6$ vs. $1.2{\pm}0.5$, p=0.011). Both groups had 1 patient with bronchopleural fistula. Chest tube duration and postoperative hospital stay were shorter in the single-port group than in the triple-port group ($8.7{\pm}5.1days$ vs. $6.2{\pm}6.6days$, p=0.130; $11.7{\pm}6.1days$ vs. $9.5{\pm}6.4days$, p=0.226). However, the differences were not statistically significant. In the single-port group, the rate of conversion to multi-port VATS lobectomy was 11.5% (3 of 26). The rates of conversion to open thoracotomy in the triple-port and single-port groups were 7.7% and 3.8%, respectively (p=1.000). Conclusion: In comparison with the triple-port group, single-port VATS lobectomy showed similar results in safety and efficacy, indicating that single-port VATS lobectomy is a feasible and safe option for lung cancer patients.

Public Shared Service Centers for Collaborative Government: A Case Study of the United States and the United Kingdom (협업정부 구현을 위한 행정공유서비스센터 도입방안 연구 - 정부 공유서비스센터 선진국 사례연구를 기반으로 -)

  • Hong, Kil Pyo;Chung, Choong Sik;Kim, Pan Suk
    • Informatization Policy
    • /
    • v.21 no.3
    • /
    • pp.33-55
    • /
    • 2014
  • Public Shared Service Centers (PSSC) consolidate functions such as human resources, information technology, financial management or accounting into one office to serve an organization. A prominent example from the United States is the Federal Information Technology Shared Services Strategy. It supports mission, administrative, and infrastructure-related IT functions through providing organizations in the Executive Branch of the Federal Government (Federal Agencies) with policy guidance on the full range and lifecycle of intra- and inter-agency information technology (IT) shared services. This study looks at the Federal Information Technology Shared Services Strategy in order to draw lessons for fostering collaborative government through the use of PSSC. It finds the following factors are critical for success when implementing IT shared services: (1) agency leadership must be solidly behind their IT shared service plan, or the needed changes will not happen at the business unit, program, or system levels; (2) there must be a move away from internally-centered, program-specific thinking, and a move toward a paradigm of consuming and providing IT shared services with multiple groups whenever possible; and (3) successfully managing "loss of control" issues is central, and optimizing business processes is essential to move from stove-piped workflows to processes that work across the agency enterprise and beyond. Therefore, the study suggests that a Korean model of PSSC implementation be introduced, and that good IT Governance is a crucial component of PSSC strategies.

Current status of Atomic and Molecular Data for Low-Temperature Plasmas

  • Yoon, Jung-Sik;Song, Mi-Young;Kwon, Deuk-Chul
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2015.08a
    • /
    • pp.64-64
    • /
    • 2015
  • Control of plasma processing methodologies can only occur by obtaining a thorough understanding of the physical and chemical properties of plasmas. However, all plasma processes are currently used in the industry with an incomplete understanding of the coupled chemical and physical properties of the plasma involved. Thus, they are often 'non-predictive' and hence it is not possible to alter the manufacturing process without the risk of considerable product loss. Only a more comprehensive understanding of such processes will allow models of such plasmas to be constructed that in turn can be used to design the next generation of plasma reactors. Developing such models and gaining a detailed understanding of the physical and chemical mechanisms within plasma systems is intricately linked to our knowledge of the key interactions within the plasma and thus the status of the database for characterizing electron, ion and photon interactions with those atomic and molecular species within the plasma and knowledge of both the cross-sections and reaction rates for such collisions, both in the gaseous phase and on the surfaces of the plasma reactor. The compilation of databases required for understanding most plasmas remains inadequate. The spectroscopic database required for monitoring both technological and fusion plasmas and thence deriving fundamental quantities such as chemical composition, neutral, electron and ion temperatures is incomplete with several gaps in our knowledge of many molecular spectra, particularly for radicals and excited (vibrational and electronic) species. However, the compilation of fundamental atomic and molecular data required for such plasma databases is rarely a coherent, planned research program, instead it is a parasitic process. The plasma community is a rapacious user of atomic and molecular data but is increasingly faced with a deficit of data necessary to both interpret observations and build models that can be used to develop the next-generation plasma tools that will continue the scientific and technological progress of the late 20th and early 21st century. It is therefore necessary to both compile and curate the A&M data we do have and thence identify missing data needed by the plasma community (and other user communities). Such data may then be acquired using a mixture of benchmarking experiments and theoretical formalisms. However, equally important is the need for the scientific/technological community to recognize the need to support the value of such databases and the underlying fundamental A&M that populates them. This must be conveyed to funders who are currently attracted to more apparent high-profile projects.

  • PDF

A Study on the Validation of Vector Data Model for River-Geospatial Information and Building Its Portal System (하천공간정보의 벡터데이터 모델 검증 및 포털 구축에 관한 연구)

  • Shin, Hyung-Jin;Chae, Hyo-Sok;Hwang, Eui-Ho
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.17 no.2
    • /
    • pp.95-106
    • /
    • 2014
  • In this study, the applicability of a standard vector model was evaluated using RIMGIS vector data and a portal based river-geospatial information web service system was developed using XML and JSON based data linkage between the server and the client. The RIMGIS vector data including points, lines, and polygons were converted to the Geospatial Data Model(GDM) developed in this study and were validated by layers. After the conversion, it was identified that the attribute data of a shape file remained without loss. The GeoServer GDB(GeoDataBase) that manages a DB in the portal was developed as a management module. The XML-based Geography Markup Language(GML) standards of OGC was used for accessing to and managing vector layers and encoding spatial data. The separation of data content and expression in the GML allowed the different expressions of the same data, convenient data revision and update, and enhancing the expandability. In the future, it is necessary to improve the access, exchange, and storage of river-geospatial information through the user's customized services and Internet accessibility.

Distal Soft-Tissue Procedure with or without Proximal Metatarsal Osteotomy for Mild to Moderate Hallux Valgus (중등도 이하의 변형을 보이는 무지외반증에서 연부조직 교정술과 근위부 절골술의 비교)

  • Cho, Duck-Yun;Kim, Hee-Chun;Seon, Chang-Wan
    • Journal of Korean Foot and Ankle Society
    • /
    • v.1 no.1
    • /
    • pp.5-11
    • /
    • 1997
  • Multiple surgical procedures for the correction of hallux valgus have been described. The surgical algorithm is based on the degree of deformity, patient's age, and the presence or absence of arthritis. It is known that the role of an isolated distal soft-tissue procedure is limited and the procedure must be used in conjunction with the proximal metatarsal osteotomy to correct most hallux valgus. We reviewed retrospectively the clinical & radiological results of distal soft-tissue procedure with or without proximal metatarsal osteotomy, performed in 18 patients (29 cases ) who had mild to moderate degrees af hallux valgus deformity. The results were as follows : In 20 cases with isolated soft-tissue procedures, the preoperative hallux valgus angle (HV) averaged 30.6 degrees and the postoperative HV averaged 7.3 degrees. The preoperative intermetatarsal angle (IM) averaged 12.5 degrees and postoperative IM averaged 10.4 degrees. 2. In 9 cases with the proximal metatarsal osteotomy added, the preoperative HV averaged 32.5 degrees, and the postoperative HV averaged 8.0 degrees. The preoperative IM averaged 12.5 degrees, and postoperative IM averaged 10.1 degrees. 3. There was no significant difference of loss of correction, presence of complication, patients own satisfaction, between two groups. In conclusion, as for the patients with mild to moderate degrees of hallux valgus deformities, the clinical and radiological results following distal soft tissue procedure and proximal metatarsal osteotamy are not proved to be superior to those following isolated soft-tissue procedures.

  • PDF