• Title/Summary/Keyword: Critical Number

Search Result 2,519, Processing Time 0.03 seconds

The Improvement of Point Cloud Data Processing Program For Efficient Earthwork BIM Design (토공 BIM 설계 효율화를 위한 포인트 클라우드 데이터 처리 프로그램 개선에 관한 연구)

  • Kim, Heeyeon;Kim, Jeonghwan;Seo, Jongwon;Shim, Ho
    • Korean Journal of Construction Engineering and Management
    • /
    • v.21 no.5
    • /
    • pp.55-63
    • /
    • 2020
  • Earthwork automation has emerged as a promising technology in the construction industry, and the application of earthwork automation technology is starting from the acquisition and processing of point cloud data of the site. Point cloud data has more than a million data due to vast extent of the construction site, and the processing time of the original point cloud data is critical because it takes tens or hundreds of hours to generate a Digital Terrain Model (DTM), and enhancement of the processing time can largely impact on the efficiency of the modeling. Currently, a benchmark program (BP) is actively used for the purpose of both point cloud data processing and BIM design as an integrated program in Korea, however, there are some aspects to be modified and refined. This study modified the BP, and developed an updated program by adopting a compile-based development environment, newly designed UI/UX, and OpenGL while maintaining existing PCD processing functions, and expended compatibility of the PCD file formats. We conducted a comparative test in terms of loading speed with different number of point cloud data, and the results showed that 92 to 99% performance increase was found in the developed program. This program can be used as a foundation for the development of a program that reduces the gap between design and construction by integrating PCD and earthwork BIM functions in the future.

Lung Function Trajectory Types in Never-Smoking Adults With Asthma: Clinical Features and Inflammatory Patterns

  • Kim, Joo-Hee;Chang, Hun Soo;Shin, Seung Woo;Baek, Dong Gyu;Son, Ji-Hye;Park, Choon-Sik;Park, Jong-Sook
    • Allergy, Asthma & Immunology Research
    • /
    • v.10 no.6
    • /
    • pp.614-627
    • /
    • 2018
  • Purpose: Asthma is a heterogeneous disease that responds to medications to varying degrees. Cluster analyses have identified several phenotypes and variables related to fixed airway obstruction; however, few longitudinal studies of lung function have been performed on adult asthmatics. We investigated clinical, demographic, and inflammatory factors related to persistent airflow limitation based on lung function trajectories over 1 year. Methods: Serial post-bronchodilator forced expiratory volume (FEV) 1% values were obtained from 1,679 asthmatics who were followed up every 3 months for 1 year. First, a hierarchical cluster analysis was performed using Ward's method to generate a dendrogram for the optimum number of clusters using the complete post-FEV1 sets from 448 subjects. Then, a trajectory cluster analysis of serial post-FEV1 sets was performed using the k-means clustering for the longitudinal data trajectory method. Next, trajectory clustering for the serial post-FEV1 sets of a total of 1,679 asthmatics was performed after imputation of missing post-FEV1 values using regression methods. Results: Trajectories 1 and 2 were associated with normal lung function during the study period, and trajectory 3 was associated with a reversal to normal of the moderately decreased baseline FEV1 within 3 months. Trajectories 4 and 5 were associated with severe asthma with a marked reduction in baseline FEV1. However, the FEV1 associated with trajectory 4 was increased at 3 months, whereas the FEV1 associated with trajectory 5 was persistently disturbed over 1 year. Compared with trajectory 4, trajectory 5 was associated with older asthmatics with less atopy, a lower immunoglobulin E (IgE) level, sputum neutrophilia and higher dosages of oral steroids. In contrast, trajectory 4 was associated with higher sputum and blood eosinophil counts and more frequent exacerbations. Conclusions: Trajectory clustering analysis of FEV1 identified 5 distinct types, representing well-preserved to severely decreased FEV1. Persistent airflow obstruction may be related to non-atopy, a low IgE level, and older age accompanied by neutrophilic inflammation and low baseline FEV1 levels.

Current Status and Developments of Comparative Education at Universities in Korea and World Wide (세계적 동향에 비추어 본 우리나라 대학의 비교교육학 교육현황과 과제)

  • Hyun, Kyung S.;Park, Elisa L.
    • Korean Journal of Comparative Education
    • /
    • v.18 no.4
    • /
    • pp.1-26
    • /
    • 2008
  • The purpose of this study is to present the overall landscape of Comparative Education study in teacher training program at universities in Korea. The Comparative Education in Korea is relatively young without a lengthy tail on its name and still on the way of upgrading itself, however various efforts are gathering for the development of Comparative Education. With this understanding, this paper diagnoses the current status of Comparative Education in Korea by analyzing 1) the number of institutions which provide Comparative Education lectures for their teacher training program, 2) aims of Comparative Education teaching, 3) curricular and course titles, 4) teaching methods and textbooks, and 5) current issues and problems currently laid on Comparative Education in Korea designated by actual lecturers and professors who are in charge of Comparative Education lectures. The historical development of Comparative Education in Korea will be briefly presented at the beginning part of the chapter. To gauge the comparative position of Korean Comparative Education, the second half of this paper introduces the cases of Comparative Education at universities worldwide, presenting various countries' status of Comparative Education along with their developmental status. As the first research which pays an attention on the current figure of Comparative Education in Korea, it will form an impetus on why we should teach college students about comparative education and on what next step should be carried for further development of Comparative Education at universities based on the comparative understanding of other countries. Since it is in the transitional stage in terms of its development, it would be critical to have a self-analysis of the current status, which will help to lay the comprehensive understanding background for designating the future direction of its development.

Study on G. Deleuze's "Francis Bacon: The Logic of Sensation" - Focus Primarily on Concept of 'Figure' - (들뢰즈의 『감각의 논리』에 관한 연구 - '형상'개념을 중심으로 -)

  • Jin, Gi-haeng
    • Journal of Korean Philosophical Society
    • /
    • v.141
    • /
    • pp.263-286
    • /
    • 2017
  • It is well known to us that in its enlarged sense Deleuze's philosophy has confrontation with platonism that has dominated the whole western ideas, and in a narrow sense it is confrontation with representative thinking and representative arts. In other words, it's obvious what Deleuze has considered the most important in his whole of ideas is to think not in a representative way but in a non-representational way and to disentangle thinking from its representative image. To examine the way how Deleuze criticize representation, and how he overcome modern ideas is not just to make a clean breast of platonic inheritance. Because they are essential for facing up to the actual circumstances of our contemporaries who have degraded servility of totalitarian thoughts under the thinking of identity, and furthermore, it is essential for overcoming this situation and proceeding to nomadic thinking, liberating thinking. This study is not intended to be a definitive account of all his criticism of representation. Because, as is well known, Deleuze's criticism of representation contains a wide variety. And so this study were limited a relatively small number of points in Deleuze's position on representation as follows. How does Deleuze's criticism of representation has been developed in his theory of paintings? And what does it mean to us today? In this paper, I paid special regard to make sense out Deleuze's concept of 'figure' in his important writings that pertains to an analysis of his criticism of representation, Francis Bacon: The Logic of Sensation. And having traced the development process of the concept of 'figure', I want to understand the implicit meaning of the concept in constant flux of his critical thinking.

Activating the Proliferation of Keratinocyte Stem Cells by Paeonol, a Compound from Natural Herb (Paeonol에 의한 표피줄기세포 활성화)

  • Kim, Do Hyung;Kim, Hyo Jin;Yeo, Hyerin;Lee, Cheon Goo;Lee, Sang Hwa
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.42 no.2
    • /
    • pp.145-152
    • /
    • 2016
  • Epidermis is continuously regenerated by keratinocyte stem cells (KSCs) residing in basement membrane, which is critical to the survival of an organism. KSCs are believed to persist during the whole lifetime and generate an enormous number of keratinocytes, required for the maintenance of epidermis, through transit amplifying cells dividing definite times until they become differentiated. In this report, we have developed a phenolic compound, paeonol, purified from Moutan Cortex, as a KSC proliferation activator, by screening about 350 herbal compounds. The cell proliferation activation by paeonol is specific for KSC not for keratinocyte, and no significant difference in the expression of p63 protein, a KSC marker, in KSCs treated with paeonol was observed in FACS analysis with anti-p63 antibody. In the colony forming assay, paeonol-treated KSC showed improved colony forming activity more than 1.3 fold. In addition, the result of PCR array shows that the activity of paeonol is through several signal pathways involving stem cell functions. These results suggest that paeonol could enhance KSC proliferation activity without reduction in stemness and could be applied to cosmetics as a KSC activating ingredient.

A REVIEW ON THE ODSCC OF STEAM GENERATOR TUBES IN KOREAN NPPS

  • Chung, Hansub;Kim, Hong-Deok;Oh, Seungjin;Boo, Myung Hwan;Na, Kyung-Hwan;Yun, Eunsup;Kang, Yong-Seok;Kim, Wang-Bae;Lee, Jae Gon;Kim, Dong-Jin;Kim, Hong Pyo
    • Nuclear Engineering and Technology
    • /
    • v.45 no.4
    • /
    • pp.513-522
    • /
    • 2013
  • The ODSCC detected in the TSP position of Ulchin 3&4 SGs are typical ODSCC of Alloy 600MA tubes. The causative chemical environment is formed by concentration of impurities inside the occluded region formed by the tube surface, egg crate strips, and sludge deposit there. Most cracks are detected at or near the line contacts between the tube surface and the egg crate strips. The region of dense crack population, as defined as between $4^{th}$ and $9^{th}$ TSPs, and near the center of hot leg hemisphere plane, coincided well with the region of preferential sludge deposition as defined by thermal hydraulics calculation using SGAP computer code. The cracks developed homogeneously in a wide range of SGs, so that the number of cracks detected each outage increased very rapidly since the first detection in the $8^{th}$ refueling outage. The root cause assessment focused on investigation of the difference in microstructure and manufacturing residual stress in order to reveal the cause of different susceptibilities to ODSCC among identical six units. The manufacturing residual stress as measured by XRD on OD surface and by split tube method indicated that the high residual stress of Alloy 600MA tube played a critical role in developing ODSCC. The level of residual stress showed substantial variations among the six units depending on details of straightening and OD grinding processes. Youngwang 3&4 tubes are less susceptible to ODSCC than U3 and U4 tubes because semi-continuous coarse chromium carbides are formed along the grain boundary of Y3&4 tubes, while there are finer less continuous chromium carbides in U3 and U4. The different carbide morphology is caused by the difference in cooling rate after mill anneal. There is a possibility that high chromium content in the Y3&4 tubes, still within the allowable range of Alloy 600, has made some contribution to the improved resistance to ODSCC. It is anticipated that ODSCC in Y5&6 SGs will be retarded more considerably than U3 SGs since the manufacturing residual stress in Y5&6 tubes is substantially lower than in U3 tubes, while the microstructure is similar with each other.

Full Scale Testing of the Effect of Stairwell Pressurization on Pressure Differential and Flow Velocity

  • Son, Bong-Sae;Park, Kyung-Hwan;Chang, Young-Bae
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.11 no.3
    • /
    • pp.83-89
    • /
    • 2011
  • A series of full-scale testing was conducted to examine the effect of stairwell pressurization on the pressure differential between the stairwell and the auxiliary room and between the auxiliary room and the residence. Also, flow velocity profiles at open doors were measured. The building tested was a condominium that had twenty floors above the ground and two floors underground. For pressurization of the stairs, a blower was used to supply air into the stairwell at one location underground. Thirteen different cases were tested, and test variables included the number of floors with open doors and the flow rate of the air supply. When the doors on the first floor were open, the pressure differential between the stairwell and the auxiliary room was distributed almost uniformly except for locations near the first floor. When the flow rate was in the range of 180~270 CMM and the doors of one floor were open, the flow velocity could satisfy the requirement of fire safety standards and the stairwell pressure was positive at all levels. However, the minimum pressure requirement (10 Pa) could not always be satisfied. When doors on two floors were open, the flow velocity requirement could be satisfied by increasing the flow rate, but it was found impractical to satisfy the minimum pressure requirement without causing excessive pressure differential in the area near the blower.

Increased yielding effect of silica on rice grown on Akiochi soil (추낙답수도(秋落沓水稻)에 대(對)한 규산(珪酸)의 증수효과(增收效果))

  • Park, Young Dae;Kim, Yung Sup
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.4 no.1
    • /
    • pp.1-11
    • /
    • 1971
  • 1. Rice plant grown with silica had more elect leaves and heading was one week earlier with silica than without silica grown in both water culture and Akiochi soil. 2. Silica content of rice plant was apparently increased by silica application and the increase insilica was more increased by bassal application of silica than top dressing. The content of other eements in plant decreased with silica application and the trend was most noticeable in iron. 3. Rice plant low in silica were more susceptible to reaf blast, Helminthosporium, mites and smaller brown plant hopper. 4. There was no significant effect of silica on increasing the dry matter production of rice plant grown on water culture, but silica remarkerbly increased the dry matter production of rice plant grown on Akiochi soil. The increasing effect of silica on rice grown on Akiochi fields was more noticeable than that of grown on Pots. 5. In rice plant grown on Akiochi soil, number of spikelets and percentage of ripened grains were increased by application of silica. The silica effects can be increased by application of well balanced nitrogen and potassium ratio. 6. From these results, it can be concluded that silica seems to have no direct effect on rice growth, but application of silica to Akiochi soil associated with low silica supply may be critical for healthy growth of rice plant, and silica directly related to rice agronomy.

  • PDF

Study for Feature Selection Based on Multi-Agent Reinforcement Learning (다중 에이전트 강화학습 기반 특징 선택에 대한 연구)

  • Kim, Miin-Woo;Bae, Jin-Hee;Wang, Bo-Hyun;Lim, Joon-Shik
    • Journal of Digital Convergence
    • /
    • v.19 no.12
    • /
    • pp.347-352
    • /
    • 2021
  • In this paper, we propose a method for finding feature subsets that are effective for classification in an input dataset by using a multi-agent reinforcement learning method. In the field of machine learning, it is crucial to find features suitable for classification. A dataset may have numerous features; while some features may be effective for classification or prediction, others may have little or rather negative effects on results. In machine learning problems, feature selection for increasing classification or prediction accuracy is a critical problem. To solve this problem, we proposed a feature selection method based on reinforced learning. Each feature has one agent, which determines whether the feature is selected. After obtaining corresponding rewards for each feature that is selected, but not by the agents, the Q-value of each agent is updated by comparing the rewards. The reward comparison of the two subsets helps agents determine whether their actions were right. These processes are performed as many times as the number of episodes, and finally, features are selected. As a result of applying this method to the Wisconsin Breast Cancer, Spambase, Musk, and Colon Cancer datasets, accuracy improvements of 0.0385, 0.0904, 0.1252 and 0.2055 were shown, respectively, and finally, classification accuracies of 0.9789, 0.9311, 0.9691 and 0.9474 were achieved, respectively. It was proved that our proposed method could properly select features that were effective for classification and increase classification accuracy.

Evaluation of Fire Investigation as the Separation Distances for Several Types of Insulation Panels (단열패널 종류별 이격거리에 따른 화재감식 평가)

  • Kim, Jeong-Hun;Kim, Da-Seul
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.22 no.4
    • /
    • pp.403-412
    • /
    • 2021
  • Despite strengthening requirements for fire retardancy and applied buildings of insulation panels, the number of fires and influence of damage have increased. In this study, the thermal effects were evaluated as the separation distances, and three types of EPS panel, glass wool panel, and gypsum board panel were then selected. Temperature sensors on the panels were installed vertically from the ground. The fire source on the lamination layer of lumber was ignited by changes in the separation distances (0 cm, 25 cm, 50 cm) from the panels. The test results suggested that the maximum temperature was 349 ℃ in the EPS panel. The inside/outside shape changes were limited by the height of the low and middle positions until the critical point of a 25 cm separation distance. Furthermore, the combustion marks appeared after 500 s on average, and then the EPS panel with a high fire strength showed a broad "U type" pattern, glass wool panel, and gypsum board panel showed medium or narrow "V type" pattern. Therefore, the acquired data can provide valuable information for evaluating the fire risks and verifying fire investigation from buildings composed of these insulation panels.