• 제목/요약/키워드: Period sorting

검색결과 47건 처리시간 0.027초

Experiment investigation on flow characteristics of open natural circulation system

  • Qi, Xiangjie;Zhao, Zichen;Ai, Peng;Chen, Peng;Sun, Zhongning;Meng, Zhaoming
    • Nuclear Engineering and Technology
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    • 제54권5호
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    • pp.1851-1859
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    • 2022
  • Experimental research on flow characteristics of open natural circulation system was performed, to figure out the mechanism of the open natural circulation behaviors. The influence factors, such as the heating power, the inlet subcooled and the level of cooling tank on the flow characteristics of the system were examined. It was shown that within the scope of the experimental conditions, there are five flow types: single-phase stable flow, flash and geyser coexisting unstable flow, flash stable flow, flash unstable flow, and flash and boiling coexisting unstable flow. The geyser flow in flash and geyser coexisting unstable flow is different from classic geysers flow. The flow oscillation period and amplitude of the former are more regular, is a newly discovered flow pattern. By drawing the flow instability boundary diagram and sorting out the flow types, it is found that the two-phase unstable flow is mainly characterized by boiling and flash, which determine the behavior of open natural circulation respectively or jointly. Moreover, compared with full liquid level system, non-full liquid level system is more prone to boiling phenomenon, and the range of heat flux density and undercooling degree corresponding to unstable flow is larger.

Neo-Chinese Style Furniture Design Based on Semantic Analysis and Connection

  • Ye, Jialei;Zhang, Jiahao;Gao, Liqian;Zhou, Yang;Liu, Ziyang;Han, Jianguo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제16권8호
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    • pp.2704-2719
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    • 2022
  • Lately, neo-Chinese style furniture has been frequently noticed by product design professionals for the big part it played in promoting traditional Chinese culture. This article is an attempt to use big data semantic analysis method to provide effective design research method for neo-Chinese furniture design. By using big data mining program TEXTOM for big data collection and analysis, the data obtained from typical websites in a set time period will be sorted and analyzed. On the basis of "neo-Chinese furniture" samples, key data will be compared, classification analysis of overall data, and horizontal analysis of typical data will be performed by the methods of word frequency analysis, connection centrality analysis, and TF-IDF analysis. And we tried to summarize according to the related views and theories of the design. The research results show that the results of data analysis are close to the relevant definitions of design. The core high-frequency vocabulary obtained under data analysis, such as popular, furniture, modern, etc., can provide a reasonable and effective focus of attention for the designs. The result obtained through the systematic sorting and summary of the data can be a reliable guidance in the direction of our design. This research attempted to introduce related big data mining semantic analysis methods into the product design industry, to supply scientific and objective data and channels for studies on design, and to provide a case on the practical application of big data analysis in the industry.

Optimal Replacement Scheduling of Water Pipelines

  • Ghobadi, Fatemeh;Kang, Doosun
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2021년도 학술발표회
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    • pp.145-145
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    • 2021
  • Water distribution networks (WDNs) are designed to satisfy water requirement of an urban community. One of the central issues in human history is providing sufficient quality and quantity of water through WDNs. A WDN consists of a great number of pipelines with different ages, lengths, materials, and sizes in varying degrees of deterioration. The available annual budget for rehabilitation of these infrastructures only covers part of the network; thus it is important to manage the limited budget in the most cost-effective manner. In this study, a novel pipe replacement scheduling approach is proposed in order to smooth the annual investment time series based on a life cycle cost assessment. The proposed approach is applied to a real WDN currently operating in South Korea. The proposed scheduling plan considers both the annual budget limitation and the optimum investment on pipes' useful life. A non-dominated sorting genetic algorithm is used to solve a multi-objective optimization problem. Three decision-making objectives, including the minimum imposed LCC of the network, the minimum standard deviation of annual cost, and the minimum average age of the network, are considered to find optimal pipe replacement planning over long-term time period. The results indicate that the proposed scheduling structure provides efficient and cost-effective rehabilitation management of water network with consistent annual budget.

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항공사진 및 퇴적물 분석을 통한 섬진강 침실습지 경관변화와 관리방안 (A Study on the Landscape Change and Management Plan for Seomjin River Chimsil Wetland through Aerial Photograph and Sediment Analysis)

  • 이성호;장동호
    • 한국지형학회지
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    • 제27권3호
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    • pp.25-39
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    • 2020
  • This study analyzed the management plan of Seomjin River Chimsil Wetland by identifying landscape changes through aerial photographs analysis and concentrations of sedimentation. Geophysical Landscape Change Analysis showed that vegetation accounts for more than half of the total area. The Barren land and water body was somewhere repeatedly increased and decreased and made an irregular form in the study area. The soil was acidic, and no eurtophication was shown, but it was potential to form wetland. In addition, the research area has been terrestrification of sand bar for a long period of time, forming a soil layer. Although the characteristics of river deposits were shown in the study area, the grain size was a particulate matter, and the sorting was 'very poorly sorted'. In some areas of Seomjin River Chimsil Wetland, sand bars were formed, but most areas were undergoing to terrestrification. Therefore, in order to preserve the riverine area and to serve by a bridge between the land ecosystem and the underwater ecosystem, it is very necessary to remove some vegetation, create a proper waterway, and restore the wetland.

울산시 언양 지역 최종빙기 뢰스 형성과 퇴적물 특성 (The formation and characteristics of loess sediments during the last glacial period in the Eonyang area, Ulsan-si, Korea)

  • 윤순옥;박충선;황상일
    • 한국지형학회지
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    • 제19권4호
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    • pp.157-168
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    • 2012
  • 언양단면은 울산광역시 울주군 삼남면 신화리의 삼동천이 태화강에 유입하는 지점에 위치한다. 언양단면에서 OSL 연대측정, 대자율, Y값 및 입도 분석 등 다양한 물리적 분석을 행하였다. 상부층의 조립 물질은 바람에 의해 주로 근거리에서 운반되었으며, 점이층과 하부층의 조립 물질은 유수에 의해 퇴적되었다. 언양단면은 대자율 변화의 불규칙성, Y값의 높은 편차, 매우 불량한 분급 등 한국의 봉동, 거창, 대천 등 다른 지역 퇴적층과 차이가 크다. 이러한 언양단면의 특성은 기존의 중국 뢰스고원과 인접한 범람원 등 다양한 기원지로부터 운반되었거나 다른 작용의 영향을 전체적으로 받았을 가능성을 시사한다. 언양단면의 퇴적물은 MIS 3 후기부터 MIS 2 시기까지 형성되었다.

만성 정신분열증 환자의 인지기능에 미치는 Clozapine 장기치료의 효과 (The Effect of Long-term Treatment with Clozapine on Cognitive Functions in Chronic Schizophrenic Patients)

  • 이홍식;김지현;전지용;정민정
    • 생물정신의학
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    • 제1권1호
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    • pp.109-116
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    • 1994
  • 연구배경: 정신분열증 환자에서 보이는 인지기능의 장애와 음성증상과의 관계는 아직 정확히 밝혀져 있지 않다. 음성증상을 효과적으로 호전시키는 것으로 알려진 clozapine을 만성 정신분열증 환자들에게 9개월 간 투여하여 인지기능이 호전될 수 있는지 조사하고 임상증상의 호전 정도와 인지기능의 호전정도 사이의 상관 관계를 평가하였다. 방 법: 만성정신분열증 환자(16명)를 대상으로 Wisconsin Card Sorting Test, Digit Span Test 및 Judgment of Line Orientation Test 등의 심리검사를 clozapine 투약 전과 9개월 후 각각 실시하였다. 또한 BPRS를 사용하여 투약전과 9개월 간의 투약 이후의 정신병리를 평가하였으며 이를 신경심리검사 결과와 비교하였다. 결 과: Clozapine은 만성정신분열증 환자의 양성 및 음성 증상을 모두 유의하게 호전시켰다. 신경심리검사 결과 집중력, 단기 기억력, 시각-지각력에는 유의한 호전이 있었으며 집행능력에서도 통계적으로 의의있지는 않으나 호전되는 경향을 보였다(p=0.066). 환자들의 임상증상과 신경심리검사 결과 사이에는 아무런 상관관계도 발견할 수 없었다. 결 론: 만성정신분열증 환자들에서 clozapine 장기 투여를 통해 임상증상은 물론 집중력 및 단기기억력 등 일부 인지기능의 호전을 기대할 수 있으며 특히 보다 정교한 정보처리와 관련되는 집행능력 역시 9개월 이상 장기 치료를 통해서 호전될 수 있음을 시사하였다. 또한 정신분열증 환자에서 나타나는 인지기능의 장애는 임상증상에 의한 2차적 현상이 아니라 하나의 독립된 병리임을 추측할 수 있다. 향후 보다 객관적인 결론을 위하여 타 항정신병약물과의 비교 연구가 지속적으로 필요하다고 본다.

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표층퇴적물 분석을 통한 동계 안면도 바람아래해수욕장 주변의 퇴적환경 변화특성 (Characteristics Variation of the Sedimentary Environment in Winter Season around the Baramarae Beach of Anmyeondo Using Surface Sediment Analysis)

  • 장동호;김장수;박노욱
    • 한국지형학회지
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    • 제17권1호
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    • pp.15-27
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    • 2010
  • 이 연구는 바람아래해수욕장 주변의 퇴적물 입도조성을 시·공간적으로 분석하여 퇴적환경 변화특성을 고찰하고자 하였다. 연구결과, 2009년 겨울철 표층퇴적물은 크게 자갈, 모래, 역질사, 역니질사, 니질사, 실트질사, 모래질실트 등의 7개 퇴적상으로 구분되었다. 평균입도를 시계열 분석(2002~2009)한 결과, 간석지 퇴적물은 평균 입도가 세립해지고, 분급은 불량해졌다. 그러나 해빈지역은 동일시기에 퇴적물의 입도가 조립화 되었고 분급이 양호해졌다. 이러한 결과는 해빈과 간석지의 퇴적환경 변화가 서로 다른 경향성을 가지고 있기 때문이다. 즉, 할미섬을 중심으로 남서쪽 해빈지역은 외해로 열려 있어 상대적으로 고에너지 환경으로 세립질 퇴적물이 제거되는 환경에서 퇴적된 결과이다. 간석지 중 가장 안쪽의 만입지의 세립화는 왕복성 조류에 의해서 유입된 퇴적물이 정조시에 퇴적되었거나 지형적인 영향에 의한 에너지 감소로 퇴적된 것으로 판단된다. 남서쪽 외해 쪽의 간석지들의 세립화 원인은 규모가 큰 섬옷섬이 외해로부터 유입되는 파랑을 막아주어 상대적으로 저에너지 환경 하에 놓이면서 조석의 영향을 받으면서 세립질 퇴적물질들이 지속적으로 퇴적된 결과로 판단된다.

사중극자 유전영동 트랩에서의 입자의 동특성에 관한 연구 (Analysis of Particle Motion in Quadrupole Dielectrophoretic Trap with Emphasis on Its Dynamics Properties)

  • 니치 찬드라세카란;이은희;박재현
    • 대한기계학회논문집B
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    • 제38권10호
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    • pp.845-851
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    • 2014
  • 유전영동(DEP)이란 비균질의 전기장과 그에 따라 입자 내부에 형성되는 극성힘에 의해 용매에 분산되어 있는 입자에 야기되는 운동을 의미하며, 세포, 바이러스, 나노입자 등의 트래핑, 입자분류, 셀분리 등과 같은 다양한 생물학적 응용에 이용되어 왔다. 지금까지 유전영동트랩에 대한 해석은 주기평균 ponderomotive force 에 기반한 정특성 해석이 주를 이루고 있으며, 동특성에 대해서는 많은 연구가 이루어져 있지 않다. 이는 지금까지 유전영동트랩이 적용된 입자들의 크기가 상대적으로 매우 크기 때문으로, 분석입자의 크기가 매우 작은 나노단위 분석에서는 적절하지 않다. 본 연구에서는, 다양한 시스템 파라미터들에 대한 트래핑의 동역학적 반응 및 그들의 트래핑 안정성에 대한 영향을 심도깊게 관찰하고자 한다. 특히, 입자의 전도율에 따른 입자의 동특성의 변화 또한 관찰하고자 한다.

암의 원인지각에 관한 탐색적 연구 -Q 방법론 적용- (An Inquiry into Causal Perceptions of Cancer)

  • 김분한
    • 대한간호학회지
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    • 제24권3호
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    • pp.364-376
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    • 1994
  • This study was initiated to find the characteristic awareness of disease in Korean culture and then, with its applying to psychological nursing, to help cancer victims cope with their disease. Research period was from Dec. 1, 1989 to Aug.3, 1992. The research method, while the method of face-to-face interview with 33 cancer victims were mainly adopted, was to identify the causal perception through analyses of literature and traditional sayings deeply rooted in Korean culture. The causal perceptions were differentiated into 4 sections, which apply to 32 cancer victims with Q-sorting. Be-ing coded into grades from 1 to 9, the data were analyzed with the aid of Quanal program on PC ; in analyzing Q-factor principal component analysis method was used. The results were revealed as follows : 1. Subject victims owe their disease to 1) the omnipotent and animating powers in Shamanism rooted in Korean culture, 2) their intimate persons, i.e. their husband, wife, children, or other fellows ameng their groups. 3) victims themselves, and 4) nowhere, for they thought the disease is the struggle with their own self. 2. In Q-methodology analysis, cancer victims are categorized into 5 types. The first type, self-mastery type, consisting of 11 subjects, has the characteristic of overcoming their disease with their own strong will or by the help of the Omnipotent God, which is estimated to be the ideal type to cope with the disease. The second type, omnipotent & animating powers-dependent type, consisted of 7 subjects, who have the causal perception of traditional shamanism. The third type, intimate person-dependent type, consisted of 4, all of whom are women and whose causal perception has the characteristic of the their complains about each member of their family, espectially about their husband. The fourth type, fate-recipient type, was the com-plex form of the first and the second types. It consisted of 6 subjects, to whom cancer had meant bad fate coming on them but had to be overcome by their strong will. The fifth type, personal type, consisted of 4, whose causal perception is toward themselves personality It is hoped that the study provide the chance of developing nursing intervention to help cancer victims accept and overcome their disease as their own reality instead of attributing to anyone or any-thing else.

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정신분열병 환자의 인지 기능 재활에 대한 보드게임 요법의 효과 분석 (The Effects of Board-Game Therapy on Cognitive Rehabilitation in Patients with Chronic Schizophrenia)

  • 윤탁;정안순
    • 생물정신의학
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    • 제13권2호
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    • pp.82-94
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    • 2006
  • Objectives : In order to explore effects of board-game therapy for cognitive rehabilitation in patients with schizophrenia, we investigated the change of executive cognitive function over a 2-month period of board-game therapy in patients with schizophrenia. Methods : Two groups of chronic schizophrenic inpatients were participated in this study. One group(n=21) were treated with board-game therapy for 2 months and the other control group(n=19) were not treated. For the evaluation of the executive cognitive function, a Wisconsin Card Sorting Test(WCST) was administered before and after the introduction of the board-game therapy. PANSS score change was also evaluated. Result : At the beginning of this study, there was no significant difference in performance of cognitive function tests, demographical data or clinical severity between both patient groups. After 2 months of treatment with the board-game therapy, the board-game therapy group showed significant improvements of executive cognitive function without any significant change of their schizophrenic symptoms. On the contrary, there was no change in control group. Conclusion : This study showed that a board-game therapy is effective for the enhancement of executive cognitive function in patients with chronic schizophrenia. A board-game therapy could be introduced with ease into psychiatric fields, such as inpatients' or outpatients' clinic wards and day hospital. Our result indicates that the board-game therapy is a promising tool for the enhancement of cognitive function, especially executive cognitive function and helpful for cognitive rehabilitation for schizophrenic patients.

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