• Title/Summary/Keyword: structural work

Search Result 2,854, Processing Time 0.036 seconds

The Effects of Functional Capacity and Depression on the Life Satisfaction among the Elderly: Focused on the Mediating Effects of Spirituality (노인의 기능적 능력과 우울이 삶의 만족도에 미치는 영향: 영성의 매개효과를 중심으로)

  • Park, Sunae;Hur, Junsoo
    • 한국노년학
    • /
    • v.37 no.1
    • /
    • pp.125-149
    • /
    • 2017
  • The purpose of this study is to analyse the mediating effects of spirituality on the relationship between functional capacity and depression among the elderly. The conceptual framework was based on the integrated theory by Brief et al.(1993) to life satisfaction. The sample was collected through convenience sampling of 413 elderly persons who were 65 years of age or older drawn from senior welfare centers, community senior centers, and religious institutions in Seoul, Incheon, and Gyeonggi Province. Data analysis was performed using Structural Equation Modeling(SEM). The main findings of the present study are as following: First, spirituality had the mediated effects on which depression and IADL influenced life satisfaction. Particularly, existential spirituality on life satisfaction had larger effect size than religious spirituality. Second, the results showed that religious spirituality had positive effects on existential spirituality. These findings demonstrate that the development and implementation of programs geared for fostering religious spirituality and existential spirituality of senior citizens are needed to improve life satisfaction in the field of social welfare. To this end, the foundation of spiritual practice in the field of social work with older people should be constructed through a spirituality-related system and professional training.

Seismic behavior of K-type eccentrically braced frames with high strength steel based on PBSD method

  • Li, Shen;Wang, Chao-yu;Li, Xiao-lei;Jian, Zheng;Tian, Jian-bo
    • Earthquakes and Structures
    • /
    • v.15 no.6
    • /
    • pp.667-685
    • /
    • 2018
  • In eccentrically braced steel frames (EBFs), the links are fuse members which enter inelastic phase before other structure members and dissipate the seismic energy. Based on the force-based seismic design method, damages and plastic deformations are limited to the links, and the main structure members are required tremendous sizes to ensure elastic with limited or no damage. Force-based seismic design method is very common and is found in most design codes, it is unable to determine the inelastic response of the structure and the damages of the members. Nowadays, methods of seismic design are emphasizing more on performance-based seismic design concept to have a more realistic assessment of the inelastic response of the structure. Links use ordinary steel Q345 (the nominal yielding strength $f_y{\geq}345MPa$) while other members use high strength steel (Q460 $f_y{\geq}460MPa$ or Q690 $f_y{\geq}690MPa$) in eccentrically braced frames with high strength steel combination (HSS-EBFs). The application of high strength steels brings out many advantages, including higher safety ensured by higher strength in elastic state, better economy which results from the smaller member size and structural weight as well as the corresponding welding work, and most importantly, the application of high strength steel in seismic fortification zone, which is helpful to popularize the extensive use of high strength steel. In order to comparison seismic behavior between HSS-EBFs and ordinary EBFs, on the basis of experimental study, four structures with 5, 10, 15 and 20 stories were designed by PBSD method for HSS-EBFs and ordinary EBFs. Nonlinear static and dynamic analysis is applied to all designs. The loading capacity, lateral stiffness, ductility and story drifts and failure mode under rare earthquake of the designs are compared. Analyses results indicated that HSS-EBFs have similar loading capacity with ordinary EBFs while the lateral stiffness and ductility of HSS-EBFs is lower than that of EBFs. HSS-EBFs and ordinary EBFs designed by PBSD method have the similar failure mode and story drift distribution under rare earthquake, the steel weight of HSS-EBFs is 10%-15% lower than ordinary EBFs resulting in good economic efficiency.

A Study on the Element Technologies in Flame Arrester of End Line (선박의 엔드라인 폭연방지기의 요소기술에 관한 연구)

  • Pham, Minh-Ngoc;Choi, Min-Seon;Kim, Bu-Gi
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.25 no.4
    • /
    • pp.468-475
    • /
    • 2019
  • An end-line flame arrester allows free venting in combination with flame protection for vertical vent applications. End-line flame arresters are employed in various fields, especially in shipping. In flame arresters, springs are essential parts because the spring load and the spring's elasticity determine the hood opening moment. In addition, the spring has to work under a high-temperature condition because of the burning gas flame. Therefore, it is necessary to analyze the mechanical load and elasticity of the spring when the flame starts to appear. Based on simulations of the working process of a specific end-line flame arrester, a thermal and structural analysis of the spring is performed. A three-dimensional model of a burned spring is built using computational fluid dynamics (CFD) simulation. Results of the CFD analysis are input into a finite element method simulation to analyze the spring structure. The research team focused on three cases of spring loads: 43, 93, and 56 kg, correspondingly, at 150 mm of spring deflection. Consequently, the spring load was reduced by 10 kg after 5 min under a $1,000^{\circ}C$ heat condition. The simulation results can be used to predict and estimate the spring's load and elasticity at the burning time variation. Moreover, the obtained outcome can provide the industry with references to optimize the design of the spring as well as that of the flame arrester.

A Study on the Design Change History Management for BIM-based Architecture-Structure Collaboration (BIM 기반 건축-구조분야 협업을 위한 설계변경 이력관리 방안 연구)

  • Park, kyoung Jun;Ock, Jong Ho
    • Korea Science and Art Forum
    • /
    • v.37 no.3
    • /
    • pp.135-145
    • /
    • 2019
  • IFC(Industry Foundation Classes) is used for information exchange in BIM-based collaboration process, and it does not secure reliability of information exchange results between fields due to structural limitations. In the end, it is a realistic problem that we have to use specialized BIM software by field, and we can not secure smooth interoperability in the process of information exchange and change. This study was conducted to find ways to secure the interoperability of BIM work between architecture and structure fields by utilizing Open Source provided by software developers to solve these problems. First, through expert survey and in-depth interview, information and improvement factors required in the process of collaboration between architecture and structure were derived. Second, in order to find a solution to the improvement factors, existing studies related to Open-API and domestic and overseas APIs were investigated and analyzed. Third, Ad-On was developed to secure interoperability by using Open API, mainly BIM S/W, which is mainly used in each field. As a result of the study, the possibility of securing interoperability through the management of the design change history between fields was confirmed by using API. It is judged that the application range of API will be expanded to the construction and maintenance field in the future. Therefore, in order to increase the usability for application diffusion, further research on interface improvement through user-centered verification is needed.

The mediating effect between the degree to provide emotional labor and personal relationship in the intent to stay for Care worker (돌봄 여성노동자의 감정노동수행정도와 직무지속의사와의 관계에 있어 대인관계의 매개효과)

  • Ji, Eun Gu;Kim, Min Ju;Lee, Won Ju
    • 한국사회정책
    • /
    • v.20 no.3
    • /
    • pp.141-170
    • /
    • 2013
  • The purpose of this study is to find out the relationship among the degree to provide emotional labor, personal relationship and the intent to stay of female care service workers. Specifically, this study focuses on the mediating effect of the personal relationship (client and agency relation). The path analysis and structural equation modeling analysis were performed on the collected data using SPSS18.0. and AMOS 8.0. And Sobel test conducted for examine the mediating effect. The results are the followings. First, the result of the analysis showed that agency relationship was an indirect factor as the partial mediating effect on relationship between the degree to provide emotional labor and the intent to stay for the care women workers. The result suggests that education utilizing various techniques and strategies to overcome the difficulty accompanied by emotional labor such as communication education and the government try to effort managing and controlling the agency which impact on the labor condition of care workers. Second, the government also tries to provide the trust and collaboration network system which construct a good relationship between the care worker and the agency.

Laos 2017: The Coexistence of Political Stagnation and Economic Change (라오스 2017: 정치적 정체와 경제적 변화의 혼재)

  • LEE, Yo Han
    • The Southeast Asian review
    • /
    • v.28 no.1
    • /
    • pp.145-171
    • /
    • 2018
  • Laos' 2017 is a year of political "stagnation" and economic "change". In the political arena, despite the achievements such as the improvement of the corruption perception index (CPI), it is necessary to watch the progress of the reform. Diplomatically, the influence of China is expected to increase further. In particular, since November 2017, Xi Jinping's visit to Laos is expected to strengthen the framework of cooperation between the economic corridor and Lanchang-Mekong Cooperation Meeting. And Laos continued to have friendly relations with other neighboring countries, the ASEAN countries. However, the issue of the Laos-Cambodian border issue following the general election in Cambodia may recur. The economic sector maintained a high growth rate due to capital inflows from the construction of large infrastructures and the favorable tourism industry, but structural problems such as deficits in the fiscal and current account should be resolved. Korea and Laos discussed the comprehensive cooperation between the two countries through the Mekong Senior Officials' Meeting in March 2017 and the Ministerial Meeting of the Korean-Lao Foreign Minister in September 2017. Laos is Korea's eighth ODA aid (grant), and ODA will become an important diplomatic cooperation channel between the two countries in the future. In the economic relationship, the trade sector is on a declining trend, but investment and human exchanges are steadily increasing.

Contribution of Two-Stage Mixing Approach on Compressive Strength of Mortar Made of Recycled Fine Aggregate (2단계 배합방법이 순환잔골재 혼입 모르타르의 압축강도에 미치는 영향)

  • Kim, Yu-Jin;Kim, Gyu-Won;Chung, Chul-Woo
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.8 no.4
    • /
    • pp.490-497
    • /
    • 2020
  • This work has been initiated to find possibility whether recycled fine aggregate can be used as a source of aggregate for structural concrete or not. Two-stage mixing approach was chosen in order to maximize strength potential from recycled fine aggregate. Moisture content of the recycled fine aggregate was changed, and two different types of two-stage mixing approaches were applied to produce cement mortar. The strength of mortar made of 100% recycled fine aggregate by two-stage mixing approaches was compared to that of mortar made of 100% washed sea sand. According to the results, the effect of moisture content on compressive strength was observed from low water cement mortar(W/C 0.3). In case of W/C 0.5 cement mortar, no clear relationship was observed between moisture content and strength development. It was found that two-stage mixing approach has a potential to increase the strength of mortar made of 100% recycled fine aggregate. In case of modified version of two-stage mixing approach which first prepares cement paste and pours recycled fine aggregate into the cement paste, was more effective to increase the strength of mortar made of 100% recycled fine aggregate.

3D Printing-Based Ultrafast Mixing and Injecting Systems for Time-Resolved Serial Femtosecond Crystallography (시간 분해 직렬 펨토초 결정학을 위한 3차원 프린팅 기반의 초고속 믹싱 및 인젝팅 시스템)

  • Ji, Inseo;Kang, Jeon-Woong;Kim, Taeyung;Kang, Min Seo;Kwon, Sun Beom;Hong, Jiwoo
    • Korean Chemical Engineering Research
    • /
    • v.60 no.2
    • /
    • pp.300-307
    • /
    • 2022
  • Time-resolved serial femtosecond crystallography (TR-SFX) is a powerful technique for determining temporal variations in the structural properties of biomacromolecules on ultra-short time scales without causing structure damage by employing femtosecond X-ray laser pulses generated by an X-ray free electron laser (XFEL). The mixing rate of reactants and biomolecule samples, as well as the hit rate between crystal samples and x-ray pulses, are critical factors determining TR-SFX performance, such as accurate image acquisition and efficient sample consumption. We here develop two distinct sample delivery systems that enable ultra-fast mixing and on-demand droplet injecting via pneumatic application with a square pulse signal. The first strategy relies on inertial mixing, which is caused by the high-speed collision and subsequent coalescence of droplets ejected through a double nozzle, while the second relies on on-demand pneumatic jetting embedded with a 3D-printed micromixer. First, the colliding behaviors of the droplets ejected through the double nozzle, as well as the inertial mixing within the coalesced droplets, are investigated experimentally and numerically. The mixing performance of the pneumatic jetting system with an integrated micromixer is then evaluated by using similar approaches. The sample delivery system devised in this work is very valuable for three-dimensional biomolecular structure analysis, which is critical for elucidating the mechanisms by which certain proteins cause disease, as well as searching for antibody drugs and new drug candidates.

The Effect of Resource Scarcity on Ageism in the Younger Generation: The Moderating Effect of Socioeconomic Status (자원 부족이 청년세대의 노인차별주의에 미치는 영향: 사회경제적 지위의 조절효과를 중심으로)

  • Lee, Inyeong;Park, Hyekyung
    • Korean Journal of Culture and Social Issue
    • /
    • v.27 no.2
    • /
    • pp.139-165
    • /
    • 2021
  • In this study, we focused on the socio-structural factors that cause ageism, investigating whether the influence of the resource scarcity on ageism in the younger generation depends on socioeconomic status. To test this hypothesis, we conducted an online study of 219 adults in their 20s and 30s. Specifically, participants were randomly assigned to either the resource scarcity priming condition or the control condition, and completed a writing task. After this, participants responded to ageism and socioeconomic status items. As a result, the effect of resource scarcity on ageism was not significant. However, we found that socioeconomic status moderated the impact of resource scarcity on ageism. In other words, resource scarcity priming has been shown to significantly reduce ageism for individuals who have relatively lower socioeconomic status. This finding is in line with previous studies in which people of low socioeconomic status were found to be more sympathetic to socially disadvantaged individuals suffering deleterious situations such as resource scarcity. This work is significant in that we have looked at both the situational and personal factors influencing ageism, and in that we have attempted to examine the causal influence of resource scarcity on ageism through an experimental approach. However, since the alternative explanation of the findings has not been completely excluded, replication through further studies will be necessary.

The Effect of Ground Heterogeneity on the GPR Signal: Numerical Analysis (지반의 불균질성이 GPR탐사 신호에 미치는 영향에 대한 수치해석적 분석)

  • Lee, Sangyun;Song, Ki-il;Ryu, Heehwan;Kang, Kyungnam
    • Journal of the Korean GEO-environmental Society
    • /
    • v.23 no.8
    • /
    • pp.29-36
    • /
    • 2022
  • The importance of subsurface information is becoming crucial in urban area due to increase of underground construction. The position of underground facilities should be identified precisely before excavation work. Geophyiscal exporation method such as ground penetration radar (GPR) can be useful to investigate the subsurface facilities. GPR transmits electromagnetic waves to the ground and analyzes the reflected signals to determine the location and depth of subsurface facilities. Unfortunately, the readability of GPR signal is not favorable. To overcome this deficiency and automate the GPR signal processing, deep learning technique has been introduced recently. The accuracy of deep learning model can be improved with abundant training data. The ground is inherently heteorogeneous and the spacially variable ground properties can affact on the GPR signal. However, the effect of ground heterogeneity on the GPR signal has yet to be fully investigated. In this study, ground heterogeneity is simulated based on the fractal theory and GPR simulation is carried out by using gprMax. It is found that as the fractal dimension increases exceed 2.0, the error of fitting parameter reduces significantly. And the range of water content should be less than 0.14 to secure the validity of analysis.