• Title/Summary/Keyword: four point problems

Search Result 161, Processing Time 0.023 seconds

Development and Characterization of High Temperature Filter (내열성여과포의 개발 및 기초성능 규명)

  • 박영옥;구철오;임정환;김홍룡;손재익;이영우
    • Journal of Energy Engineering
    • /
    • v.7 no.1
    • /
    • pp.103-112
    • /
    • 1998
  • A high temperature fabric filter was developed and characterized in order to solve the various problems encountered in the operation of industrial fabric filters. Four kinds of dusts generated in the typical domestic industry were used for its characterization, coke dust from a steel manufacturing process, cement dust from a cement manufacturing process, fly ash from a fluidized-bed combustor, and incinerator ash from a waste plastics incinerator. The physical and chemical properties of the high temperature fabric filter were analyzed in terms of mean flow pore pressure, bubble point pore diameter, mean flow pore diameter, pore size distribution, and the changes in tensile strength and initial elastic modulus under $SO_2$ and $NO_2$ atmospheres. Pressure drop, dust penetration, and figure of merit for the fabric filter were also investigated in a bench-scale filter testing unit. The fabric filter developed in this study had good physical and chemical filter properties and showed a very applicability to typical industrial dusts treatments.

  • PDF

A Study on the Evaluating Indicators of the Level of Deterioration in High-rise and high-density Apartments (고층고밀 아파트단지의 노후도 평가지표 개발)

  • Cho, Sung-Heui;Lee, Tae-Kyung
    • Journal of the Korean housing association
    • /
    • v.20 no.4
    • /
    • pp.131-142
    • /
    • 2009
  • High-rise and high-density apartment complexes have been built and supplied on a large scale in the 1st period of the New Town project in metropolitan areas since the late 1980s. Now It has become necessary to improve those apartment complexes, which have serious deterioration problems for aging more than about 20 years accompanying simultaneity and a large scale. The purpose of this research is to develop the evaluating indicators to measure the level of deterioration of apartments inclusively and practically in order to regenerate apartments as sustainable residential environments. This study is composed of the following four parts; (a) establishing the conceptual model of evaluation of apartment deterioration, (b) selecting evaluation items, (c) constituting evaluation measurement, and(d)weighting evaluation indicators. First, deterioration of apartments was conceptualized by physical. social, and economical aspects in terms of sustainable development and proposed the conceptual model of hierarchy structure of evaluation of apartment deterioration by literature reviews. Second, evaluating items were selected based on literature reviews of existing indicators and preceding studies about apartments of Korea and foreign countries. The evaluating indicators were identified as a total of 77 evaluating items which were composed of three dimensions and 9 attributes on the basis of the conceptual model. They cover comprehensive scope of the apartment such as unit, building, complex, and site. Third, as the measurement, the 5 point ordinal scale measure was suggested. The evaluating measurement including measure standards, measure methods, and measure contents were developed by each evaluating items. Lastly, the weighting of evaluating indicators was analyzed by AHP method conducted by survey on the expert group. Items were identified as high contributors or low contributors. The weighting of these items could suggest several evaluations according to the situation. The evaluation of the level of deterioration can be done by both total evaluation and a specific field of evaluation. In addition, it is easy to grasp deteriorated attributes or dimensions by providing a radar and bar chart showing evaluation results. These evaluating indicators could be a useful tool to grasp actual methods for the regeneration of apartments.

The Characteristic of the Clothing behavior of Gay Men According to Gay Identity - Focusing on the Drama - (게이 자아 정체성에 따른 게이의 의복 특성 - 드라마 <퀴어 애즈 포크>를 중심으로 -)

  • Lee, Min-Sun;Kim, Min-Ja
    • Journal of the Korean Society of Costume
    • /
    • v.62 no.6
    • /
    • pp.1-18
    • /
    • 2012
  • This study explores the clothing behavior of homosexual men for identity creation. Since homosexuality has been viewed in terms of immoral, medical or social problems, gay males have made efforts to construct presentational styles in order to hide or reveal their sexual identities. Kate Schofield and Ruth A. Schmidt found that there were three different layers of individual gay identity construction expressed in clothing: shared gay identity, tribal identity, and situational identity. Using their framework, 630 gay men's outfits found in the U.S drama 'Queer as folk' were analyzed, which dealt with the lives of a group of gay men living in Pittsburgh, Pennsylvania. Findings point that gay males use their clothing effectively to express their sexual identity. Firstly, they use certain fashion items as the signifier of homosexuality on a gay community level. They use their clothing to attract the sexual partners. On tribal identity level, diverse and fragmented styles could be shown besides the effeminate style. Homosexual men's clothing can be classified into the following four dominate styles: the drag look, the macho look, the androgynous look and conventional look. Findings also indicate that gay males make different clothing choices for different situations in order to blend into the heterosexual or homosexual society.

Open heart surgery of Ebstein's anomaly -Report of 12 cases- (Ebstein 기형에 대한 개심술 -12례 보고-)

  • Ahn, Hyuk;Park, Yee-Tae;Rho, Joon-Ryang;Suh, Kyung-Phill;Lee, Yung-Kyoon
    • Journal of Chest Surgery
    • /
    • v.16 no.2
    • /
    • pp.157-163
    • /
    • 1983
  • Ebstein's anomaly is a rare congenital cardiac malformation oand the ideal surgical correction seems controversial at present, and some problems are left unsolved in the surgical correction of this anomaly. Between June 1978 and June 1982, 12 patients with Ebsteins' anomaly underwent corrective open heart surgery at Seoul National University Hospital. Except for one patient, who had no ASD, all had a huge right atrium, secundum type ASD, and definite atrialized right ventricle. Typically, displaced tricuspid valve leaflets were found in all cases, but the degree of displacement and deformity were variable. In the point of NYHA functional classification, five were in class II, six were in class III, and one was in class IV. Ten patients were operated on by tricuspid valve replacement and pication. Two patients were operated on only by plication and annuloplasty techniques, and in all cases, ASD was closed. Postoperatively, four patients suffered from complete A-V block, and two of them died immediately. The remaining two patients took pacemaker generator implantation with good results. The other eight patients were in good condition. Tricuspid valve replacement using tissue valve and plication of the atrialized rght ventricle seems to be a good method of surgical correction for Ebstein's anomaly.

  • PDF

DEVELOPMENT OF DENTULOUS STOCK TRAYS FOR KOREANS (한국형 유치악용 기성트레이의 개발에 관한 연구)

  • Song, Dae-Sung;Kang, Seok-Ku;Cho, Hye-Won;Dong, Jin-Keun
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.34 no.4
    • /
    • pp.755-779
    • /
    • 1996
  • This study was designed to development of stock tray for Korean. The subjects for this study were 374 persons(male : 204, female : 170) with age $19{\sim}28$. The study models were made with irreversible hydrocolloid impression material and conventional stock tray, Individual trays were made on the study model and the master models were made after impression with polysulfide rubber impression material. Each of the master models measured 12 measuring points on the maxillary model and 13 measuring points on the mandibular model with digital sliding caliper. The values were analyzed statistically by SAS analysis. The measuring points were analysed and were consulted for the development of new stock tray for Korean. Maxillary models were divided into four groups acceding to the width between buccal alveolar ridges below the contact point of first molar and second molar. The size of new tray of the upper first group was 82mm (width), 60mm(length). That of the upper second group was 77mm (width), 59mm (length). That of the upper third group was 72mm (width), 58mm (length). And that of the upper fourth group was 67mm (width), 57mm (length). Mandibular models were devided into three group according to the width between lingual alveolar ridges below the second molar. The size of new tray on lower first group was 40mm (width), 55mm (length). That of the lower second group was 36mm (width), 55mm (length). And that of the third group was 32mm (width), 55mm (length). The author tested the fitness of newly designed stock tray in 52 subjects with normal occlusion and obtained good results that the problems of conventional stock tray were worked out.

  • PDF

Analysis on Current State and Development Cases of Ubiquitous Tourism Information Service (유비쿼터스 관광 정보서비스 구축 현황 및 사례 분석)

  • Kim, Hyun-Jeong
    • The Journal of the Korea Contents Association
    • /
    • v.10 no.1
    • /
    • pp.407-416
    • /
    • 2010
  • As ubiquitous technology has been developed and has come into everyday life, it has been integrated to tourism information service. However, each regional government develops ubiquitous tourism information service independently without successful example or standard. Therefore, this paper aims to analyze existing cases of domestic ubiquitous tourism information service as a foundation research to establish standard and effective development strategy for accelerating ubiquitous tourism information service in the future. First, ubiquitous technology trend which can be adapted to tourism information service was reviewed by secondary research. Second, representative cases of ubiquitous tourism information service were collected and analyzed in four aspects such as adapted ubiquitous technology, adapted device, service content and type of content. Finally, overall development strategy of ubiquitous tourism information service was discussed based on the analysis result. This paper contributes to get an outline of present conditions and problems of existing ubiquitous tourism information service, suggest overall development direction for ubiquitous tourism information service and point out necessity of the standard and unified plan for nationwide development and management.

A Study on the Service Quality Evaluation of Public Libraries by the Use of LibQUAL+: The Case of Public Libraries in Seoul that Contracting Out to Private Sector (LibQUAL+를 적용한 공공도서관 서비스 품질 평가에 관한 연구 - 서울시 소재 민간위탁 공공도서관을 중심으로 -)

  • Ryu, Ju-Hyun;Lee, Sang-Bok
    • Journal of the Korean BIBLIA Society for library and Information Science
    • /
    • v.23 no.2
    • /
    • pp.271-294
    • /
    • 2012
  • This study is designed to evaluate the service quality of public libraries according to managing entities by LibQUAL+ and to devise ways to improve problems based on comparison and analysis of the differences in the service qualities. To achieve this, four public libraries in Seoul according to the managing entities were investigated. They consisted of libraries of public corporations, cultural centers, foundations and universities. Minimum service quality level, desired service quality level and perceived service quality was analyzed based on nine-point Lickertis scale. A survey was employed and consisted of twenty-two items. The results showed that current level of service met the minimum level, yet failed to reach their desired service level. The study suggested that public libraries contracting out to private sector need to actively apply users' demands and the changing environment of libraries, and continue to strive to provide public library users with high quality service through efforts of evaluating and improving the services for their users.

Mixed-mode fatigue crack growth behaviors in 5083-H115 aluminum alloy (5083-H115 알루미늄 합금의 혼합 모우드 피로 균열성장 특성)

  • 옹장우;진근찬;이성근;김종배
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.13 no.3
    • /
    • pp.461-471
    • /
    • 1989
  • For the mixed-mode crack problems the direction of crack growth, the crack path and the rational representation of fatigue crack growth rates should be studied to predict fatigue life and safety of structures. In this study, a round specimen which produce nearly identical effects in all loading directions is proposed to make an easy measurement of initial direction of crack growth. The mode I and mode II stress intensity factors of the specimen were calculated using finite element method, in which the square root singular stresses at the crack tip are modeled by means of four rectangular quarter-point eight-noded elements surrounding the crack tip. Experimental results for high strength aluminum alloy showed that the direction of mixed-mode crack growth agree well with maximum principal stress criterion as well as minimum strain energy density criterion, but not with maximum shear stress criterion. From data of fatigue crack growth rates using crack geometry projected on the line perpendicular to the loading direction it is easily established that mixed-mode fatigue crack growth in 5083-H115 aluminum alloy goes predominantly with mode I crack growth behaviors.

The Characteristics of "Wooded Fortress of Beopseongjin in Yeonggwang" and Perspectives on the Problems of Landscape Management ("영광 법성진 숲쟁이" 의 특성 분석과 경관관리 문제점 고찰)

  • Choi, Jai-Ung;Kim, Dong-Yeob
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.13 no.6
    • /
    • pp.13-24
    • /
    • 2010
  • Beopseongpo has been one of the most thriving ports of the Jeolla region since the Goryeo Dynasty (918-1392). During the time of King Seongjong (r. 1469-1494) of Choseon Dynasty, a navy garrison had been deployed and the port was named Beopseongjin, as recorded in the 1485 edition of Grand code for state administration (Gyeongguk daejeon). Dangsan forests and Bibo forests have been maintained by local residents since hundreds of years ago. Dangsan forests have been applied to the scale of government and public offices. The objectives of this study were to understand the characteristics of the "Wooded Fortress of Beopseongjin in Yeonggwang" as "Scenic Site No. 22", and to investigate the conservational problem of the wooded fortress of Beopseongjin and seashore. The "Wooded fortress of Beopseongjin in Yeonggwang" consists of a Dangsan forest and two Bibo forests. But, the presence of the Dangsan forest has not been well known to the public. Although the wooded fortress has been somewhat disturbed by cultural activities, the Dangsan rituals have been held until the present every January 15 by lunar calendar. On the other hand, the seashore in front of Beopseongpo plays an important role as a scenic view. It was one of the reason that the "Wooded fortress of Beopseongjin in Yeonggwang" had been designated as a national cultural property of "Scenic Sites". However, the sandbar was reclaimed in 2009 to build commercial buildings. An integrated plan should be prepared to conserve the landscape of "Wooded fortress of Beopseongjin in Yeonggwang", which requires close partnership among local residents, experts, and local government. At present, four new buildings have been built. Although we have lost the sandbar, it is indispensable to secure the visibility of Wooded Fortress of Beopseongjin at the entrance of the village.

Structural efficiency of various strengthening schemes for cold-formed steel beams: Effect of global imperfections

  • Dar, M. Adil;Subramanian, N.;Dar, A.R.;Majid, Muheeb;Haseeb, Mohd;Tahoor, Mugees
    • Steel and Composite Structures
    • /
    • v.30 no.4
    • /
    • pp.393-403
    • /
    • 2019
  • Cold-formed steel (CFS) has a great potential to meet the global challenge of fast-track and durable construction. CFS members undergo large buckling instabilities due to their small wall thickness. CFS beams with corrugated webs have shown great resistance towards web buckling under flexure, when compared to the conventional I-sections. However, the magnitude of global imperfections significantly affects the performance of CFS members. This paper presents the first attempt made to experimentally study the effect of global imperfections on the structural efficiency of various strengthening schemes implemented in CFS beams with corrugated webs. Different strengthening schemes were adopted for two types of beams, one with large global imperfections and the other with small imperfections. Strength and stiffness characteristics of the beams were used to evaluate the structural efficiency of the various strengthening schemes adopted. Six tests were performed with simply supported end conditions, under four-point loading conditions. The load vs. mid-span displacement response, failure loads and modes of failure of the test specimens were investigated. The test results would compensate the lack of experimental data in this area of research and would help in developing numerical models for extensive studies for the development of necessary guidelines on the same. Strengthening schemes assisted in enhancing the member performance significantly, both in terms of strength and stiffness. Hence, providing an economic and time saving solution to such practical structural engineering problems.