• Title/Summary/Keyword: Spatial Behavior

Search Result 930, Processing Time 0.038 seconds

Basic Study on Flame-Stabilization Characteristics in a Multi-Channel Combustor via a Model of a Porous-Media Combustor (다공성 연소기 모델로서의 다중 채널 연소기 내부 화염의 안정화 특성 기초 연구)

  • Park, Seung-Il;Lee, Min-Jung;Kim, Nam-Il
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.35 no.8
    • /
    • pp.815-823
    • /
    • 2011
  • Combustion phenomena in porous media combustors are widely used in industrial fields for the combustion of lowgrade fuels and the regeneration of combustion heat. However, studies of combustion phenomena in porous media have been limited, because these phenomena are difficult to observe, and the configurations of porous media are complex. We propose a simple model combustor: a multi-channel combustor that consists of many layers of combustion channels made of quartz plates. We conducted an experimental observation of the flames in the multi-channel combustor and obtained experimental results for the flame stabilization limits. Flames formulated in the multi-channel combustor showed variation in the spatial distribution depending on the heat transfer between neighboring channels. A simple analytical model was developed and the variation in the flammability limits of the multi-channel combustor was discussed. This study will enhance our understanding of flame behavior in a porous-media combustor.

An Assumed Strain Beam Element for Spatial Post-Buckling Analysis of Non-symmetric and Shear Flexible Thin-Walled Beams (박벽보의 3차원 후좌굴 해석을 위한 Locking-Free 보요소)

  • Lee, Kyoung-Chan;Kim, Moon-Young;Park, Jung-Il;Chang, Sung-Pil
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.20 no.6
    • /
    • pp.719-730
    • /
    • 2007
  • This study presents a thin-walled space frame element based on the classical Timoshenko beam theory. The element is derived according to the assumed strain field in order to resolve the shear-locking phenomenon. The shape function is developed in accordance with the strain field which is assumed to be constant at a 2-noded straight frame element. In this study, the geometrically nonlinear analysis applies the Corotational procedure in order to evaluate unbalanced loads. The bowing effect is also considered faithfully. Two numerical examples are given; monosymmetric curved and nonsymmetric straight cantilever. When these example structures behave lateral-torsional bucking, the critical loads are obtained by this study and ABAQUS shell elements. Also, the post-buckling behavior is examined. The results give good agreement between this study and ABAQUS shell.

The Development and Application of Wetland Ecology Map Program for the Study through Experience at Upo Swamp (우포늪 체험 학습을 위한 습지 생태 지도 프로그램 개발 및 적용)

  • Yang, Eun-Ju;Kim, Kee-Dae
    • Hwankyungkyoyuk
    • /
    • v.23 no.2
    • /
    • pp.97-112
    • /
    • 2010
  • The study aims to comprehend the effect of the wetland ecology education on the elementary school students' changes of recognition about wetland through the wetland ecology map program. In this study, the literary research, the experimental research and the survey methods were operated. Through the literary research, the environmental factors were extracted, and the writing item of ecology map was reconstructed based on the literary research, so the experimental research was operated with the wetland ecology map program. Through four areas of test items such as the information and knowledge, values and attitudes, development and conservation, behavior and participation, and the analysis of children's study results, the effect of the wetland ecology map program on changes of recognition about wetland was verified quantitatively and qualitatively. Wetland ecology map program would be able to be an educational approach which can achieve the 'personalization of environment' setting up predictable environmental improvement goals and satisfying the needs of spatial information of the appropriate regions from the holistic perspective that students themselves plan and participate beyond a one-time experience program. Production of ecological map through continuous monitoring is expected to improve the possibility of subjective environmental actions by operating self-directed learning. Based on the conclusion of this study, we would suggest the following. For wetland ecology map program to be supplemented and utilized, the basic education of wetland should be organized in regular school curriculum, ecology map program including various teaching learning methods be prepared actively, and in future studies, studies of ecosystem-wide wetland ecology map program including animals like birds and fish are necessary.

  • PDF

Development of Distributed Rainfall-Runoff Model Using Multi-Directional Flow Allocation and Real-Time Updating Algorithm (I) - Theory - (다방향 흐름 분배와 실시간 보정 알고리듬을 이용한 분포형 강우-유출 모형 개발(I) - 이론 -)

  • Kim, Keuk-Soo;Han, Kun-Yeun;Kim, Gwang-Seob
    • Journal of Korea Water Resources Association
    • /
    • v.42 no.3
    • /
    • pp.247-257
    • /
    • 2009
  • In this study, a distributed rainfall-runoff model is developed using a multi-directional flow allocation algorithm and the real-time runoff updating algorithm. The developed model consists of relatively simple governing equations of hydrologic processes in order to apply developed algorithms and to enhance the efficiency of computational time which is drawback of distributed model application. The variability of topographic characteristics and flow direction according to various spatial resolution were analyzed using DEM(Digital Elevation Model) data. As a preliminary process using fine resolution DEM data, a multi-directional flow allocation algorithm was developed to maintain detail flow information in distributed rainfall-runoff simulation which has strong advantage in computation efficiency and accuracy. Also, a real-time updating algorithm was developed to update current watershed condition. The developed model is able to hold the information of actual behavior of runoff process in low resolution simulation. Therefore it is expected the improvement of forecasting accuracy and computational efficiency.

A Comparative Study on the Emotional Space Characteristics of the Museums Designed by Wright, Corbusier, and Mies (라이트.꼬르뷔제.미스의 감성적 뮤지엄 공간 특성에 관한 비교연구)

  • Suh, Swoo-Kyung
    • Korean Institute of Interior Design Journal
    • /
    • v.16 no.6
    • /
    • pp.189-196
    • /
    • 2007
  • The purpose of this study is to make a comparative analyzation toward abstracted emotional properties appeared in the museum exhibition spaces designed by the three masters of the modern architecture;Frank Lloyd Wright, Le Corbusier and Mies van der Rohe. In addition, this study will also aim to inquire into how the emotional properties have affected the third generation architects. It is especially expected that the 'emotional tendency' emerging in various fields of the present time can serve as useful information through the analysis of emotional design properties appeared in the exhibition space which is directly linked with the human lives. In order to achieve the purpose of the study, in New York by Wright, in Tokyo by Le Corbusier and in Berlin by Mies Van der Rohe were selected. As for the analyzation methodology to be adopted for deriving the aiming points at the emotional design, five criteria of analyzation have been established in order to understand the properties of the emotional area: they are (1) spatial affordance, (2) human congeniality, (3) emotional factors of the area, (4) constitution of the area and (5) expressive division of the area. Using these criteria, this study will reveal what are some of the emotional characteristics shown in each museums and its analytical result will be useful to apply to future museum design. It is especially expected that the 'emotional tendency' emerging in various fields of the present time can serve as useful information through the analysis of emotional design properties appeared in the exhibition space of design which is directly linked with the human behavior.

Similar Trajectory Retrieval on Road Networks using Spatio-Temporal Similarity (시공간 유사성을 이용한 도로 네트워크 상의 유사한 궤적 검색)

  • Hwang Jung-Rae;Kang Hye-Young;Li Ki-Joune
    • The KIPS Transactions:PartD
    • /
    • v.13D no.3 s.106
    • /
    • pp.337-346
    • /
    • 2006
  • In order to analyze the behavior of moving objects, a measure for determining the similarity of trajectories needs to be defined. Although research has been conducted that retrieved similar trajectories of moving objects in Euclidean space, very little research has been conducted on moving objects in the space defined by road networks. In terms of real applications, most moving objects are located in road network space rather than in Euclidean space. In similarity measure between trajectories, however, previous methods were based on Euclidean distance and only considered spatial similarity. In this paper, we define similarity measure based on POI and TOI in road network space. With this definition, we present methods to retrieve similar trajectories using spatio-temporal similarity between trajectories. We show clustering results for similar trajectories. Experimental results show that similar trajectories searched by each method and consistency rate between each method for the searched trajectories.

Rainfall Trend Detection Using Non Parametric Test in the Yom River Basin, Thailand

  • Mama, Ruetaitip;Bidorn, Butsawan;Namsai, Matharit;Jung, Kwansue
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2017.05a
    • /
    • pp.424-424
    • /
    • 2017
  • Several studies of the world have analyzed the regional rainfall trends in large data sets. However, it reported that the long-term behavior of rainfall was different on spatial and temporal scales. The objective of this study is to determine the local trends of rainfall indices in the Yom River Basin, Thailand. The rainfall indices consist of the annual total precipitation (PRCTPOP), number of heavy rainfall days ($R_{10}$), number of very heavy rainfall days ($R_{20}$), consecutive of dry days (CDD), consecutive of wet days (CWD), daily maximum rainfall ($R_{x1}$), five-days maximum rainfall ($R_{x5}$), and total of annual rainy day ($R_{annual}$). The rainfall data from twelve hydrological stations during the period 1965-2015 were used to analysis rainfall trend. The Mann-Kendall test, which is non-parametric test was adopted to detect trend at 95 percent confident level. The results of these data were found that there is only one station an increasing significantly trend in PRCTPOP index. CWD, which the index is expresses longest annual wet days, was exhibited significant negative trend in three locations. Meanwhile, the significant positive trend of CDD that represents longest annual dry spell was exhibited four locations. Three out of thirteen stations had significant decreasing trend in $R_{annual}$ index. In contrast, there is a station statistically significant increasing trend. The analysis of $R_{x1}$ was showed a station significant decreasing trend at located in the middle of basin, while the $R_{x5}$ of the most locations an insignificant decreasing trend. The heavy rainfall index indicated significant decreasing trend in two rainfall stations, whereas was not notice the increase or decrease trends in very heavy rainfall index. The results of this study suggest that the trend signal in the Yom River Basin in the half twentieth century showed the decreasing tendency in both of intensity and frequency of rainfall.

  • PDF

Visual Analysis of Regional Variations in Antidepressant Use and Suicide Rate (항우울제 사용 및 자살률의 지역적 편차에 대한 시각적 분석)

  • Kim, Ho-Jung;Lee, Iyn-Hyang
    • Korean Journal of Clinical Pharmacy
    • /
    • v.28 no.4
    • /
    • pp.308-319
    • /
    • 2018
  • Background: Some mental illnesses such as depression are known to be one of the risk factors of suicide and proper antidepressant therapy can reduce suicidal behavior. Objectives: This study aimed to analyze regional variations in antidepressant consumption and adherence, suicide rate, prevalence of suicide related mental disorders, and access to relevant healthcare services. Methods: Cross-sectional analyses were conducted using National Patients Sample data compiled by the Health Insurance Review and Assessment Service between 2014 and 2016. We included patients who had a diagnosis record of suicide related mental disorders during the study period. Cause of death statistics and National health and medical statistics were used to identify suicide rate and distribution of healthcare service. We conducted visual analyses, chi-squared tests, independent t-tests and correlation analyses to demonstrate regional variations. Results: Between 2014 and 2016, the average prevalence of suicide related mental disorders was 5.4 per cent. Suicide rate and prevalence of suicide related mental disorders were higher in Gangwon, Chungcheong, and Jeolla (p < 0.001), and lower in Seoul (p < 0.001) than the national average. Unexpectedly, regional variations in antidepressant consumption were seen in the limited area including Daejeon, Chungnam and Gyeongnam (p < 0.05). The number of mild patient-centered clinics was associated positively with antidepressant consumption (p < 0.01) and associated negatively with suicide rate (p < 0.01). Conclusion: There were some regional variations in prevalence of suicide related mental disorders, antidepressant adherence and suicide rate. The higher level of antidepressant therapy and the lower level of suicide rates were seen in regions with easy access to mild patient-centered clinics.

A Study on the Disabled' Use Behavior and Needs towards the Library Space (도서관 공간에 대한 장애인 이용행태 및 요구 분석)

  • Bae, Kyung-Jae
    • Journal of Korean Library and Information Science Society
    • /
    • v.50 no.2
    • /
    • pp.25-42
    • /
    • 2019
  • This study identified the experiences that the disabled actually feel in the library space in the face of growing social demands for spatial functions in public libraries. This study also tried to determine the requirements for the space that disabled wanted. For the research, 15 subjects were selected for each of the five people who were blind, deaf, and handicapped with experience using the library and individual in-depth interviews were conducted for the research. The study found that the experience of the disabled in the library space differed by type of disability and generally more negative experiences were found than positive ones. Misperception about the disabled of library staff and the non-disabled were having a significant impact on the disabled's negative experience for library space. There were a wide variety of opinions on the requirements for library space and there were generally negative perceptions about the current level of library space for the Integrated library service space.

The Water Deer on a Road: Road-Kill Characteristics of a Nationally Abundant but Internationally Threatened Species

  • Kim, Kyungmin;Seo, Hyunjin;Woo, Donggul;Park, Taejin;Song, Euigeun
    • Journal of Forest and Environmental Science
    • /
    • v.37 no.1
    • /
    • pp.62-68
    • /
    • 2021
  • Despite numerous efforts on reducing road-kill worldwide, the collisions have been occurring continuously. Many factors are affecting road-kill occurrences and the effect is various by species. We investigated Hydropotes inermis argyropus road-kill characteristics on the national highway. We examined 9,099 H. i. argyropus road-kill points with distance to the gaps on road (interchange and intersection) and distance to six natural land-cover types as explanatory variables. We also examined the number of road-kill occurrences according to temporal variation using chi-square test with 9,658 events. In general, H. i. argyropus road-kill location tended to occur close to the gaps on road, agricultural lands and forests. The average distance from road-kill to the gap was 694.7 m and 78.6% of the collisions were occurred within 1 km from the gaps. In addition, Kruskal-Wallis test showed the distance between road-kill points and each land cover and the gaps was significantly different. The temporal analyses showed that the differences of the H. i. argyropus road-kill frequency are significant in both month and season. Our results implies H. i. argyropus road-kill location tended to occur close to the gaps on road, agricultural lands and forests in general, especially during May and June, according to their seasonal behavior. Thus, we suggest there is a need of concentrated management on the roads with specific characteristics for both wildlife and human safety.