• Title/Summary/Keyword: self-construction

검색결과 1,193건 처리시간 0.025초

Elevated temperature resistance of concrete columns with axial loading

  • Alaskar, Abdulaziz;Alyousef, Rayed;Alabduljabbar, Hisham;Alrshoudi, Fahed;Mohamed, Abdeliazim Mustafa;Jermsittiparsert, Kittisak;Ho, Lanh Si
    • Advances in concrete construction
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    • 제9권4호
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    • pp.355-365
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    • 2020
  • The influence of temperature on the material of concrete filled columns (CFCs) under axial loading has been quantitatively studied in this research. CFCs have many various advantages and disadvantages. One of the important inefficiency of classic CFCs design is the practical lack of hooped compression under the operational loads because of the fewer variables of Poisson's rate of concrete compared to steel. This is the reason why the holder tends to break away from the concrete core in elastic stage. It is also suggested to produce concrete filled steel tube columns with an initial compressed concrete core to surpass their design. Elevated temperatures have essentially reduced the strengths of steel tubes and the final capacity of CFCs exposed to fire. Thus, the computation of bearing capacity of concrete filled steel tube columns is studied here. Sometimes, the structures of concrete could be exposed to the high temperatures during altered times, accordingly, outcomes have shown a decrement in compressive-strength, then an increase with the reduction of this content. In addition, the moisture content at the minimal strength is declined with temperature rising. According to Finite Element (FE), the column performance assessment is carried out according to the axial load carrying capacities and the improvement of ductility and strength because of limitations. Self-stress could significantly develop the ultimate stiffness and capacity of concrete columns. In addition, the design equations for the ultimate capacity of concrete columns have been offered and the predictions satisfactorily agree with the numerical results. The proposed based model (FE model of PEC column) 65% aligns with the concrete exposed to high temperature. Therefore, computed solutions have represented a better perception of structural and thermal responses of CFC in fire.

Optimization of cables size and prestressing force for a single pylon cable-stayed bridge with Jaya algorithm

  • ATMACA, Barbaros;DEDE, Tayfun;GRZYWINSKI, Maksym
    • Steel and Composite Structures
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    • 제34권6호
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    • pp.853-862
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    • 2020
  • In recent years, due to the many advantages cable-stayed bridges have often constructed in medium and long span. These advantages can be listed as an aesthetically pleasing appearance, economic and easy construction, etc. The main structural elements of cable-stayed bridges are listed as deck, pylon, cables and foundation. Perhaps one of the most vital and expensive of these structural elements is stay-cables. Stay-cables ensure the allowable displacement and distribution of bending moments along the bridge deck with prestressing force. Therefore the optimum design of the stay-cables and prestressing force are very important in achieving the performance expected from the cable-stayed bridges. This paper aims to obtain the stay-cables size and prestressing force optimization of the cable-stayed bridge. For this purpose, single pylon and fan type cable configuration Manavgat Cable-Stayed Bridge was selected as an example. The three dimensional (3D) finite element model (FEM) of the bridge was created with SAP2000. Analysis of the 3D FEM of the bridge was conducted under the different combined effects of the self-weight of the structural element, prestressing force of stay-cable and live load. Stay-cable stress and deck displacement were taken into account as constraints for the optimization problem. To optimize this existing bridge a metaheuristic algorithm named Jaya was used in the optimization process. 3D FEM of the selected bridge was repeatedly analyzed by using Open Applicable Programming Interface (OAPI) properties of SAP2000. To carry out the optimization process the developed program which integrates the Jaya algorithm and the required codes for calling SAP2000 is coded in MATLAB. At the end of the study, the total weight of the stay-cables was reduced more than 40% according to existing stay cables under loads taken into account.

도서관 및 유관기관 취업 사서의 고용실태 조사 연구 (A Study on Cognitive Survey for Employment Prospect of Library and Related Organization)

  • 노영희
    • 한국도서관정보학회지
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    • 제48권1호
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    • pp.43-75
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    • 2017
  • 본 연구에서는 사서의 고용실태 및 환경, 취업전망에 대한 인식을 조사하기 위해 사서 대상 설문조사를 수행하였으며, 그 결과는 다음과 같다. 첫째, 인식조사를 기반으로 한 도서관 현장의 고용환경은 낮은 임금, 불안정한 일자리, 전공비일치 직원배치로 인한 업무의 어려움, 상사와의 불화, 사서로서의 자존감 저하, 업무량과다, 열약한 업무환경 등으로 나타났다. 둘째, 대학의 문헌정보학과 교육과정에 추가되어야 할 내용으로 현장 근무자들은 문화프로그램 관련, 전자정보 조직 및 서비스 등을 가장 높게 선호하였다. 셋째, 비정규직의 고용환경은 높은 경쟁률, 낮은 임금, 높은 이직횟수, 과다한 업무량 등으로 나타났다. 넷째, 취업준비 시 가장 큰 애로사항은 취업 정보의 부족으로 나타났다. 따라서 위의 연구결과를 기반으로 한 다양한 개선책이 요구되며, 특히, 취업정보시스템의 구축, 현장중심 교육과정의 도입, 채용시 구체적 직무조건 제시가 요구된다고 할 수 있다.

간호사의 조직 의사소통 만족과 환자안전에 대한 태도와의 관계 (Relationship Between Intra-Organizational Communication Satisfaction and Safety Attitude of Nurses)

  • 김경자;한정숙;서미숙;장봉희;박미미;함형미;유문숙
    • 간호행정학회지
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    • 제18권2호
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    • pp.213-221
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    • 2012
  • Purpose: Communication in hospitals is one of the major factors in patient safety. So, the purpose of this study was to identify the relationship between intra-organizational communication satisfaction and the safety attitude of nurses in hospitals. Method: A descriptive survey design with convenience sampling was used. Data collection was done using a self-report questionnaire answered by 278 nurses from one university hospital located in Kyeoung-gi Province, Korea. Result: Intra-organizational communication satisfaction positively correlated with safety attitude (r=.747, p<.01). Among the 6 sub dimensions of safety attitude, perceptions of management (r=.675, p<.01), job satisfaction (r=.640, p<.01) and teamwork climate (r=.600. p<.01) were strongly related to intra-organizational communication satisfaction. Multiple regression analysis was done to identify explanation power of intra-organizational communication satisfaction against safety attitude. The model was significant (F=48.540, p<.01). Intra-organizational communication satisfaction accounted for 60.9% of variance in safety attitude (Adj $R^2$=.609). Conclusions: The results of this study indicate that higher levels of intra-organizational communication satisfaction promote positive safety attitude in hospital nurses and that communication media quality is an important factor in patient safety attitude. Therefore, developing interventions to revitalize intra-organizational communication level based on communication media quality will help in the construction of positive safety attitude in nurses.

무선 랜을 이용한 MOST 네트워크 진단 시스템의 설계 및 구현 (Design and Implementation of a Diagnostic System for MOST Network using Wireless LAN)

  • 장시웅;김경진;전영준
    • 한국정보통신학회논문지
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    • 제15권8호
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    • pp.1695-1703
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    • 2011
  • 자동차의 사용자 편의 및 안전에 대한 다양한 요구로 전장 장치의 수가 증가함에 따라 이들 장치들을 보다 효과적으로 제어할 수 있도록 네트워크를 이용한 전장 시스템이 구축되고 있다. 본 논문에서는 MOST 네트워크로 연결된 장치들과 네트워크의 상태를 진단하고 이들을 효과적으로 관리하기 위하여 무선 랜을 이용한 MOST 네트워크진단 시스템을 설계 및 구현하였다. 차량 멀티미디어 네트워크 표준인 MOST는 최근 자동차의 인포테인먼트 시스템 구축에 적용되고 있으며 이를 적용한 다양한 장치들이 개발되고 있다. 본 논문에서 구현한 무선 진단 시스템은 MOST 네트워크 자가 진단뿐만 아니라 MOST 전장 장치의 상태를 진단하여 오류를 미리 판단할 수 있으며, 무선 랜으로 연결하여 언제든지 휴대형 이동 단말기를 통해서도 차량 내부 MOST 네트워크 시스템의 상태를 확인 및 관리할 수 있다.

정적재하시험을 통한 장경간 중공 웨브 PSC 거더교의 내하력 평가 (Evaluation of the Load Carrying Capacity of Existing Bridges with Long Span Hollow Web Prestressed Concrete Girder by Static Load Test)

  • 김성겸;장판기;장일영
    • 한국구조물진단유지관리공학회 논문집
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    • 제22권3호
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    • pp.97-102
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    • 2018
  • 기존 PSC I형 거더는 콘크리트의 자중, 정착구 및 긴장방식 등의 영향으로 장경간화의 적용성이 불리하였다. 이를 극복하기 위하여 PSC 거더의 복부에 중공을 도입하고 다단계 긴장을 도입함으로써 50~70m 경간에 적용 가능한 중공 웨브 PSC I형 거더를 개발하고 실교량으로 시공하였다. 본 연구는 중공 웨브 PSC I형 거더교 현장에서 정적재하시험을 통하여 계측을 한 결과와 대상 구조물의 유한요소해석 결과를 바탕으로 비교, 분석하여 중공 웨브 장경간 PSC 거더교의 공용내하력과 안전성을 평가하였다. 본 교량의 정적재하시험과 수치해석 결과가 유사하게 나타났으며 중공 웨브 PSC I형 거더의 거동을 잘 모사하는 것으로 나타났다. 교량의 모든 거더는 설계 활하중 하에서 충분한 내하력을 확보하는 것으로 평가되었고 안전성을 확보하여 시공 결과의 적절성을 확인하였다.

연안재해 저감을 위한 친수형 호안 블록개발에 관한 연구 (A Study on Hydrophilic Protection Block Development for Reduction of coastal disaster)

  • 김종길
    • 디지털융복합연구
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    • 제15권3호
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    • pp.211-219
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    • 2017
  • 연안재해 저감을 위한 정부 사업 중 연안침식 및 퇴적을 저감시키기 위한 연안정비 사업 1단계(2000년~2009년)와 2단계(2010년~2019년)가 현재까지 진행중이다. 이와 같은 연안정비 사업을 수행함에 있어 연안 보호를 위한 인공 콘크리트 피복재의 설치가 필요하다. 현재 국내에서는 일본에서 개발된 제품을 현장에 적용하고 있거나, 호안보호공 설치를 시행하는 건설사에서 자체 개발한 블록을 설치하고 있는 추세이다. 그렇지만 이에 대한 수리특성 검증 및 안정성확보 여부, 설계기법과 같은 기술적인 검토는 부족한 상황이다. 본 연구에서는 이런 점들을 보완하여 사람들의 접근성이 좋으면서 연안재해 저감 및 보호 능력이 우수한 친수형 호안 블럭을 개발하고자 한다. 본 연구를 통하여 호안블록의 수리특성 및 안정계수를 도출할 수 있었다.

의령 입산마을의 중층적 경관 특성 (A Study on the Over-layered Landscape Characteristics of Ipsan Village, Uiryeong Area)

  • 임의제;소현수;배수현
    • 농촌계획
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    • 제24권1호
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    • pp.113-127
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    • 2018
  • This study comprehends that the landscape of Ipsan Village is the accumulated output of the landscape management and social behavior by the historic personages through the reference research and field surveys. And the study sorted out the over-layered landscape characteristics of Ipsan Village by analyzing the dispersed landscape elements as follows. First, right before the start of Japanese invasions to Korea(1592-98), Tamjin(耽津) An(安) Family moved into Ipsan and started establishing the a single clan village. At a site with mountain background and facing the water(背山臨水), the village used to be a typical farming one with an organically planned road-system and housing area following the traditional order. However, the landscape has changed drastically since the 20th century with the construction of banks, roads and readjustment of arable land etc. Second, the original landscape, which can be figured out through the 'Gosanjaesibyukgyeong(高山齋十六景)' in the 18th century, shows its harmony with natural landscape: mountain & valley, stream & field, traditional trees, etc, cultural landscape: village, well, spring, etc, and momentary landscape: seasons, time, weather phenomena, sound, behavior, etc. Third, based on the second, 16 natural landscape elements: mountain & stream, planting, etc. and 25 cultural landscape elements: housing spaces, self-cultivation & ceremony spaces, community spaces and modern education & enlightenment spaces were selected and interpreted as landscaping meanings. Fourth, the over-layered landscape which stems from the compositive functions and inter-connectivity of landscape elements which consists Ipsan Village is regarded as 'Natural geographical and Fungsu landscape', 'Rural production and livelihood landscape', 'Confucian ceremony and symbolic landscape' and 'Modern education and enlightenment landscape.'

전북 지역 학교 급식 영양사의 학교 급식 시설${\cdot}$설비에 대한 만족도 연구 (A Study on School Dietitians' Satisfaction with Foodservice Facilities and Utilities in the Chonbuk Area of Korea)

  • 최혜연;노정옥
    • 한국식품영양학회지
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    • 제20권2호
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    • pp.218-225
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    • 2007
  • This study was conducted to investigate the satisfaction of school dietitians with foodservice facilities and utilities in the Chonbuk area of Korea. Self-administered questionnaires were collected from a total of 22 dietitians. Statistical data analysis was completed using the SPSS v. 10.0 program. The results are summarized as follows. Among the 222 school foodservice systems, 68.5% of the schools prepared meals the conventional way and 31.5% prepared them the commissary way. Most of the school foodservice facilities were located on the first floor. Satisfaction with the location of the foodservice facility was not significantly different between the conventional and commissary systems. However, overall dietitian satisfaction with the foodservice facility locations was poor. Approximately 30% of the dietitians responded that one of the most important problems for foodservice management was the limited space and worn-out equipments in the kitchens. For dietitians' satisfaction on the types of facilities present, most schools had constructed dietitian offices, food storage facilities, cafeterias, rest rooms, dressing rooms, and preparation facilities. Yet, the amenities most often missing were storage facilities, preparation facilities, dressing rooms, rest rooms, etc. For overall satisfaction with the status of facilities and utilities, we found no significant differences between dietitians in the conventional(2.89) and commissary foodservice systems(2.86); however, the satisfaction level among the dietitians was poor. Therefore, governmental regulation agencies need to review and approve plans prior to the new construction or extensive remodeling of school foodservice facilities. Finally, content analysis was also conducted regarding the dietitians' opinions on foodservice facilities and utilities.

The Etiology and Treatment of the Softened Phallus after the Radial Forearm Osteocutaneous Free Flap Phalloplasty

  • Kim, Seok-Kwun;Kim, Tae-Heon;Yang, Jin-Il;Kim, Myung-Hoon;Kim, Min-Soo;Lee, Keun-Cheol
    • Archives of Plastic Surgery
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    • 제39권4호
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    • pp.390-396
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    • 2012
  • Background The radial forearm osteocutaneous free flap is considered to be the standard technique for penile construction. One year after their operation, most patients experience a softened phallus, so that they suffer from difficulties in sexual intercourse. In this report, we present our experience with phalloplasty by radial forearm osteocutaneous free flap, as well as an evaluation of the etiology and treatment of the softened phallus. Methods Between March 2005 and February 2010, 58 patients underwent phalloplasty by radial forearm osteocutaneous free flap. Most of their neophallus had been softened subjectively and among them, 12 patients who wanted correction were investigated. We performed repetitive fat injection, artificial dermis grafting, silicone rod insertion, and rib bone with cartilaginous tip graft. Physical examination, plain radiograph, computed tomography, bone scintigraphy, and satisfaction scores were investigated. Results Most of the participants' penises have been softened after phalloplasty, and the skin elasticity had been also decreased. On plain radiograph, the distal end of the bone was self-rounded; however, the bone shape of the neophallus had no significant interval changes or resorption. Computed tomography showed equivocal density of cortical bone. On bone scintigraphy, the bone metabolism was active at 3 months postoperatively, and remained active 9 years postoperatively. Conclusions The use of a rib bone with cartilaginous tip graft could be an option for improvement of the softened phallus. Silicon rod insertion is also worth considering for rigidity of the softened phallus. Decreased rigidity due to soft tissue atrophy could be alleviated with repeated fat injection and artificial dermis grafting.