• 제목/요약/키워드: reserve

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전력계통 건전성 지수 알고리즘 개발 (Development of Power System Health Algorithm)

  • 임진택;이성훈;이연찬;최재석;최홍석;주준영
    • 전기학회논문지
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    • 제63권10호
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    • pp.1328-1336
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    • 2014
  • This paper proposes Power System Health Index(PSHI) newly. The paper describes several kind of power system health indices based on two main categories, which are adequacy and security. In adequacy, four kinds of health indices of Frequency, Voltage, Reserve(Operating Reserve Power and Frequency Regulation Reserve Power) and Overload of lines and transformers are proposed. In security, four kinds of health indices of Voltage(154kV, 345kV and 765kV), Overload of lines and transformers, Power flow constraint among areas and SPS are proposed. All indices are mapped with three domains, which are indicated as Health, Margin and Risk, defined with expert interview. While domains of health, margin and risk is defined similar with the conventional well being analysis of power system. The criterion of the domains is proposed using an interview with expert operators and practical reliability codes in Korea. The several kinds of health index functions, which are linear ratio, piecewise linear ration and reverse ratio function etc. are developed in this paper. It will be expected that the developed health indices can help operators to control power system more successfully and also prevent power system from accident as like as black out in future because operator can make a decision immediately based on more easily visual information of system conditions from too much indices acquisition of complex power system.

Burden of Psychiatric Disorders among Pediatric and Young Adults with Inflammatory Bowel Disease: A Population-Based Analysis

  • Thavamani, Aravind;Umapathi, Krishna Kishore;Khatana, Jasmine;Gulati, Reema
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제22권6호
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    • pp.527-535
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    • 2019
  • Purpose: There is increasing prevalence of psychiatric disorders among inflammatory bowel Disease (IBD) population. Further, presence of psychiatric disorders has been shown as an independent predictor of quality of life among patients with IBD. We intended to explore the prevalence of various psychiatric disorders among pediatric and young adult population with IBD as a population-based analysis. Methods: We did a retrospective case control analysis using a deidentified cloud-based database including health care data across 26 health care networks comprising of more than 360 hospitals across USA. Data collected across different hospitals were classified and stored according to Systematized Nomenclature of Medicine-Clinical Terms. We preidentified 10 psychiatric disorders and the queried the database for the presence of at least one of the ten psychiatric disorders among IBD patients between 5 and 24 years of age and compared with controls. Results: Total of 11,316,450 patients in the age group between 5 and 24 years and the number of patients with a diagnosis of IBD, Crohn's disease or ulcerative colitis were 58,020. The prevalence of psychiatric disorders was 21.6% among IBD mainly comprising of depression and anxiety disorder. Multiple logistic regression analysis showed, IBD is 5 times more likely associated with psychiatric disorders than controls, p<0.001). We showed a steady increasing trend in the incidence of psychiatric disorders among IBD patients (2% in 2006 to 15% in 2017). Conclusion: Largest population-based analysis demonstrated an increased prevalence of psychiatric disorders among IBD patients. Our study emphasizes the need for psychological and mental health services to be incorporated as a part of the routine IBD clinic.

Assessment of Coarse Woody Debris in Gallery Forest in the Bombo-Lumene Reserve (Democratic Republic of Congo)

  • Rusaati, Butoto Imani wa;Joo, Sung-Hyun;Yun, Gi-Yun;Park, Joowon;Cephas, Masumbuko Ndabaga;Kang, Jun-Won
    • Journal of Forest and Environmental Science
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    • 제35권3호
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    • pp.205-211
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    • 2019
  • The objective of this research was to assess the amount of carbon stock of coarse woody debris (CWD) in Bombo-Lumene Reserve. Data on lying CWD was collected on 35 circular sampling plots using Line Intersect Sampling (LIS) method. A total of 230 samples CWD (${\geq}10cm$ diameter) were inventoried. The mean carbon stocks of CWD was $29.48Mg\;C\;ha^{-1}$, ranging from 4.32 to $73.54Mg\;C\;ha^{-1}$. The CWD carbon stocks displayed a wide range of variation in decay states. The allocation of CWD among the decay class of all the CWD samples reveals that the most important classes were class 1 and class 3 with 323.66 and $321.96Mg\;C\;ha^{-1}$, followed by class 4 with 264.56 and the last one was class 2 with $121.72Mg\;C\;ha^{-1}$. The results suggested that the dead wood component is important in carbon sequestration and should be taken into consideration for quantification of carbon stocks not only in Bombo-Lumene Reserve, but in all forest ecosystems in the Democratic Republic of Congo.

한라산천연보호구역 내 버섯 종 다양성 연구 (Biodiversity research of mushrooms in hallasan mountain natural reserve)

  • 이승학;고기범;고평열
    • 한국버섯학회지
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    • 제18권4호
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    • pp.292-296
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    • 2020
  • 본 연구는 한라산천연보호구역의 기초자료 확보를 목적으로 수행된 한라산천연보호구역 기초학술조사 중 버섯류에 대한 연구로, 2018년 4월부터 10월까지 7개월 동안 성판악탐방로와 돈내코탐방로 사이 지역을 대상으로 수행되었다. 조사된 버섯은 총 65과 184속 392종이며, 이 중 187종의 버섯이 죽은 나무나 나뭇가지에서 발생하였다. 주름버섯목에 속하는 버섯이 184종으로 가장 높게 나타났고, 시기적으로는 7월에 206종으로 가장 많이 발생하였다. 또한 대부분의 버섯은 600~800 m 사이 고도에서 발생하였다. 본 연구에서 조사된 버섯들 중 기후변화 생물지표종에 해당되는 버섯이 5종, 후보종 2종이 나타났으며, 392종 중 국외 반출 승인 대상 생물자원에는 163종이 해당되었다(*Appendix 홈페이지에 업로드).

예비전력의 효시(嚆矢) 호국군(護國軍)의 성격에 관한 연구 (A study on the characteristics of the Korea National Guard the root of the reserve power)

  • 박종현
    • 융합보안논문지
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    • 제22권5호
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    • pp.127-134
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    • 2022
  • 호국군은 비록 짧은 역사였지만 대한민국 예비군제도의 효시라는 점에서 큰 의미를 가진다. 이러한 호국군에 대한 연구는 그동안 소극적으로 진행되어 왔다. 그나마도 진행된 연구는 역사적 관점에서 단편적인 서술에만 국한되어 왔고 호국군의 성격을 규명하지는 못하였다. 따라서 본 연구에서는 호국군이 존재했던 시대적 배경을 살펴본 다음 법적·제도적, 군사적, 정치적 관점의 새로운 시선에서 호국군의 성격을 규명하고자 노력하였다. 연구결과를 종합해보면 호국군은 법률적 지지를 받으면서 전시에 대비한 효율적인 제도로 탄생하였다. 그리고 선진국형 모병제도인 지원병제를 채택했다는 점, 호국군만의 별도 사관학교를 통해 장교를 양성했으며 후방지역작전에 기여했다는 점은 군사적 측면에서 높이 평가된다. 반면, 호국군을 창설하는 과정부터 정치권과 비군사단체가 결탁하였다는 점은 부정적이다. 끝으로 본 연구를 계기로 6.25전쟁 이전에 존재했던 예비전력에 관한 연구가 좀 더 활발해지기를 기대한다.

생물권보전지역에 대한 지역민 의식조사 연구 -광릉숲 생물권보전지역을 사례로- (Results of An Awareness Survey of Local Residents Regarding Biosphere Reserves -A Case Study of the Gwangneung Forest Biosphere Reserve-)

  • 박찬영;염성진
    • 한국환경과학회지
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    • 제32권12호
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    • pp.933-941
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    • 2023
  • Since the Industrial Age, economic activities have raised environmental concerns, emphasizing the importance of biodiversity conservation areas. However, a fundamental contradiction exists between conservation and utilization, leading to conflicting interests. In light of these issues, the aim of this study was to propose efficient operational strategies for future urban biodiversity conservation areas, while also promoting local community economic development. Accordingly, the focus was the Gwangneung Forest Biosphere Reserve as a case study. The findings reveal the following. First, all local residents recognize the importance of the biosphere reserve and hold a high regard for its direct role in conservation. Second, developing and promoting brands appears to have a more positive impact on local economic activation than activating projects linked to the biosphere reserve. Simultaneously, local residents have expressed negative evaluations of indiscriminate facility development, fearing reckless expansion. Third, if governance is promoted in the future, community participation will likely increase, leading to a strengthening of conservation awareness and the establishment of a framework among local residents and those in adjacent areas. Findings of this study are expected to serve as fundamental data for establishing effective communication among local residents in protected areas facing similar challenges, thus facilitating efficient decision-making processes.

Prevalence of posttraumatic stress disorder in orthopedic trauma patients and a call to implement the Injured Trauma Survivor Screen as a prospective screening protocol in the United States

  • Victoria J. Nedder;Mary A. Breslin;Vanessa P. Ho;Heather A. Vallier
    • Journal of Trauma and Injury
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    • 제37권1호
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    • pp.67-73
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    • 2024
  • Purpose: Posttraumatic stress disorder (PTSD) is prevalent and is associated with protracted recovery and worse outcomes after injury. This study compared PTSD prevalence using the PTSD Checklist for DSM-5 (PCL-5) with the prevalence of PTSD risk using the Injured Trauma Survivor Screen (ITSS). Methods: Adult trauma patients at a level I trauma center were screened with the PCL-5 (sample 1) at follow-up visits or using the ITSS as inpatients (sample 2). Results: Sample 1 (n=285) had significantly fewer patients with gunshot wounds than sample 2 (n=45) (8.1% vs. 22.2%, P=0.003), nonsignificantly fewer patients with a fall from a height (17.2% vs. 28.9%, P=0.06), and similar numbers of patients with motor vehicle collision (40.7% vs. 37.8%, P=0.07). Screening was performed at a mean of 154 days following injury for sample 1 versus 7.1 days in sample 2. The mean age of the patients in sample 1 was 45.4 years, and the mean age of those in sample 2 was 46.1 years. The two samples had similar proportions of female patients (38.2% vs. 40.0%, P=0.80). The positive screening rate was 18.9% in sample 1 and 40.0% in sample 2 (P=0.001). For specific mechanisms, the positive rates were as follows: motor vehicle collisions, 17.2% in sample 1 and 17.6% in sample 2 (P>0.999); fall from height, 12.2% in sample 1 and 30.8% in sample 2 (P=0.20); and gunshot wounds, 39.1% in sample 1 and 80.0% in sample 2 (P=0.06). Conclusions: The ITSS was obtained earlier than PCL-5 and may identify PTSD in more orthopedic trauma patients. Differences in the frequency of PTSD may also be related to the screening tool itself, or underlying patient risk factors, such as mechanism of injury, or mental or social health.

재난상황 시 예비군 긴급대응부대 창설 및 운용방안에 관한 연구 (A Study on the Establish and Operating Plan of Reserve Components Emergency Response Forces)

  • Seo, SeungBae
    • 한국재난정보학회 논문집
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    • 제14권1호
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    • pp.9-16
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    • 2018
  • 재난상황하에서는 신속한 지역단위 재난복구를 전문적으로 담당하는 인력이 필요하다. 그러나, 현재의 재난대응체계에서는 대민지원, 자원봉사 등 수준에서 재난복구를 시행하고 있으므로 전문성 부족으로 인한 초기대응 및 재난복구 지연, 재난 지속시 대응 미흡 등 다양한 문제점이 발생하고 있다. 그러므로, 재난상황시 지자체단위 초기 대응능력 구비와 신속히 재난복구를 할 수 있는 전문성을 가진 부대의 창설이 필요하다. 따라서, 본 연구에서는 재난상황하 긴급 재난복구를 통한 지역안정과 재해 주민구호, 재난이전으로의 신속한 전환을 위한 예비군 긴급대응부대를 창설과 운용방안 수준의 방향성을 제시하였다.

Short-term Reactive Power Reserve Optimization Based on Trajectory Sensitivity

  • Sun, Quancai;Cheng, Haozhong;Zhang, Jian;Li, Baiqing;Song, Yue
    • Journal of Electrical Engineering and Technology
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    • 제12권2호
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    • pp.541-548
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    • 2017
  • An increasing concern is paid to short-term voltage stability with the growth of penetration of induction motor loads. Reactive power reserve(RPR) of power system is critical to improve voltage stability. A definition of short-term voltage stability-related RPR(SVRPR) is proposed. Generators vary their contributions to voltage stability with their location and system condition, etc. Voltage support coefficient based on the second-order trace sensitivity method is proposed to evaluate SVRPR's contribution to short-term voltage stability. The evaluation method can account for the generator's reactive support in transient process and the contingency severity. Then an optimization model to improve short-term voltage stability is built. To deal with multiple contingencies, contingency weight taking into account both its probability and severity is proposed. The optimization problem is solved by primal dual interior point method. Testing on IEEE_39 bus system, it is indicated that the method proposed is effective. Short-term voltage stability is improved significantly by the way of SVRPR optimization. Hence, the approach can be used to prevent the happening of voltage collapse during system's contingency.

Design, analyses, and evaluation of a spiral TDR sensor with high spatial resolution

  • Gao, Quan;Wu, Guangxi;Yu, Xiong
    • Smart Structures and Systems
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    • 제16권4호
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    • pp.683-699
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    • 2015
  • Time Domain Reflectometry (TDR) has been extensively applied for various laboratory and field studies. Numerous different TDR probes are currently available for measuring soil moisture content and detecting interfaces (i.e., due to landslides or structural failure). This paper describes the development of an innovative spiral-shaped TDR probe that features much higher sensitivity and resolution in detecting interfaces than existing ones. Finite element method (FEM) simulations were conducted to assist the optimization of sensor design. The influence of factors such as wire interval spacing and wire diameter on the sensitivity of the spiral TDR probe were analyzed. A spiral TDR probe was fabricated based on the results of computer-assisted design. A laboratory experimental program was implemented to evaluate its performance. The results show that the spiral TDR sensor featured excellent performance in accurately detecting thin water level variations with high resolution, to the thickness as small as 0.06 cm. Compared with conventional straight TDR probe, the spiral TDR probe has 8 times the resolution in detecting the water level changes. It also achieved 3 times the sensitivity of straight TDR probe.