• Title/Summary/Keyword: structural evaluation

Search Result 4,836, Processing Time 0.033 seconds

Evaluation of unanchorage blast-resistant modular structures subjected to blast loads and human injury response

  • Ali Sari;Omer Faruk Nemutlu;Kadir Guler;Sayed Mahdi Hashemi
    • Structural Engineering and Mechanics
    • /
    • v.89 no.5
    • /
    • pp.525-538
    • /
    • 2024
  • An explosion from a specific source can generate high pressure, causing damage to structures and people in and around them. For the design of protective structures, although explosion overpressure is considered the main loading parameter, parts are only considered using standard design procedures, excluding special installations. Properties of the explosive, such as molecular structure, shape, dimensional properties, and the physical state of the charge, determine the results in a high-grade or low-grade explosion. In this context, it is very important to determine the explosion behaviors of the structures and to take precautions against these behaviors. Especially structures in areas with high explosion risk should be prepared for blast loads. In this study, the behavior of non-anchored blast resistant modular buildings was investigated. In the study, analyzes were carried out for cases where modular buildings were first positioned on a reinforced concrete surface and then directly on the ground. For these two cases, the behavior of the modular structure placed on the reinforced concrete floor against burst loads was evaluated with Stribeck curves. The behavior of the modular building placed directly on the ground is examined with the Pais and Kausel equations, which consider the structure-ground interaction. In the study, head and neck injuries were examined by placing test dummies to examine human injury behavior in modular buildings exposed to blast loads. Obtained results were compared with field tests. In both cases, results close to field tests were obtained. Thus, it was concluded that Stribeck curves and Pais Kausel equations can reflect the behavior of modular buildings subjected to blast loads. It was also seen at the end of the study that the human injury criteria were met. The results of the study are explained with their justifications.

Properties Evaluation of Polyketone for Use as Earthquake-Resistant Structural Compression Material (내진 구조용 압축재로 활용을 위한 폴리케톤의 특성 평가)

  • Lee, Heon-Woo;Noh, Jin-Won;Kim, Young-Chan;Hu, Jong-Wan
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.44 no.2
    • /
    • pp.133-139
    • /
    • 2024
  • The purpose of this study is to propose a new material called polyketone to overcome the limitations of polyurethane, which is currently used as a compression member in the field of earthquake-resistant structures. Although existing polyurethane has excellent elastic properties, it tends to be insufficient to recover the displacement that occurs in the structure. On the other hand, polyketone has excellent strength performance and is attracting attention as an eco-friendly material. In order to evaluate the compression properties of polyketone, which has these advantages, we would like to conduct a comparative experiment with polyurethane that was previously used. The speed dependence of polyketone was identified through simple compression experiments and experimental speed changes under repeated loading conditions, and additional compression behavior was applied to confirm compression behavior characteristics. Polyketone showed compressive strength about 10 times higher than that of polyurethane, and its excellent recovery characteristics were demonstrated by its deformation recovery ability about 14 times higher at relatively small displacements.

Simulation of Potential Difference Analysis in Conductor-Dielectric Type Triboelectric Generator Using COMSOL Multiphysics (COMSOL Multiphysics를 활용한 도체-유전체 형태 마찰전기 발전기의 전위차 해석 시뮬레이션)

  • Yong Hoon Son;Geon-Tae Hwang
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.37 no.6
    • /
    • pp.600-608
    • /
    • 2024
  • In the era of the Fourth Industrial Revolution, electronic devices are becoming increasingly miniaturized and lightweight to overcome spatial limitations, necessitating lower power consumption. Triboelectric nanogenerators (TENGs), which convert mechanical energy into electrical energy, offer an ideal solution as small-scale power generators for these compact devices. Recent research has focused on various materials and structural designs to maximize the output of triboelectric energy harvesters, highlighting the growing importance of theoretical structure analysis software for precise evaluation. COMSOL Multiphysics software provides an accurate method for simulating the electrical characteristics of TENGs. This Tutorial Status Report introduces the process of modeling TENGs and analyzing their electrical output using COMSOL Multiphysics

Evaluation of Structural Changes and Dispersibility of Boron Nitride Nanotubes under Different Ultrasonication Conditions (초음파 처리 조건에 따른 질화붕소나노튜브 구조 변화 및 분산성 평가)

  • Da Bin Cheon;Won Jung Choi;Seung Hwa Yoo
    • Composites Research
    • /
    • v.37 no.4
    • /
    • pp.350-355
    • /
    • 2024
  • Boron nitride nanotubes (BNNT) are materials of significant interest in next-generation technological fields due to their outstanding physicochemical properties, including excellent chemical and thermal stability. However, for effective utilization, dispersion of BNNT is essential. Unfortunately, BNNT exhibit hydrophobic surfaces and strong van der Waals forces, making their dispersion challenging. Current dispersion methods include the addition of surfactants and surface functionalization, but these chemical treatments often damage BNNT and involve cumbersome processes. In this study, we dispersed BNNT in water under various tip ultrasonication conditions and identified conditions that do not affect BNNT using FT-IR spectroscopy, Raman spectroscopy, and X-ray diffraction analysis. Subsequently, enhanced dispersibility was confirmed through turbidity measurements, and the solubility range in 15 different solvents was evaluated using the Hansen solubility parameter.

HIV-related Perceptions, Knowledge, Professional Ethics, Institutional Support, and HIV/AIDS-related Stigma in Health Services in West Sumatra, Indonesia: An Empirical Evaluation Using PLS-SEM

  • Vivi Triana;Nursyirwan Effendi;Brian Sri Pra Hastuti;Cimi Ilmiawati;Dodi Devianto;Afrizal Afrizal;Adang Bachtiar;Rima Semiarty;Raveinal Raveinal
    • Journal of Preventive Medicine and Public Health
    • /
    • v.57 no.5
    • /
    • pp.435-442
    • /
    • 2024
  • Objectives: The aim of this study was to investigate the significance of associations between knowledge, professional ethics, institutional support, perceptions regarding HIV/AIDS, and HIV/AIDS-related stigma among health workers in West Sumatra, Indonesia. Methods: We conducted a cross-sectional study involving health workers at public hospitals and health centers in West Sumatra in June 2022. The Health Care Provider HIV/AIDS Stigma Scale was employed to assess the stigma associated with HIV/AIDS. To estimate and evaluate the model's ability to explain the proposed constructs, we utilized the standardized partial least squares structural equation model (PLS-SEM). Results: In total, 283 individuals participated in this study (average age, 39 years). The majority were female (91.2%), nearly half were nurses (49.5%), and 59.4% had been working for more than 10 years. The study revealed that HIV/AIDS-related stigma persisted among health workers. The PLS-SEM results indicated that all latent variables had variance inflation factors below 5, confirming that they could be retained in the model. Knowledge and professional ethics significantly contributed to human immunodeficiency virus (HIV)-related stigma, with an effect size (f2) of 0.15 or greater. In contrast, perceived and institutional support had a smaller impact on HIV-related stigma, with an effect size (f2) of at least 0.02. The R2 value for health worker stigma was 0.408, suggesting that knowledge, professional ethics, institutional support, and perceived support collectively explain 40.8% of the variance in stigma. Conclusions: Improving health workers' understanding of HIV, fostering professional ethics, and strengthening institutional support are essential for reducing HIV-related stigma in this population.

Nasal septal anatomical variations among Saudi population and their possible coincidence with sinusitis: a computed tomography scan study

  • Gisma Ahmed Madani;Wael Amin Nasr El-Din;Asmaa S. Essawy;Khamrunissa Hussain;Islam Omar Abdel Fattah
    • Anatomy and Cell Biology
    • /
    • v.55 no.4
    • /
    • pp.423-432
    • /
    • 2022
  • The nasal septum is a crucial supporting factor for the nasal cavity and may develop several anatomical variants including septal deviation, spur and pneumatization. These variants could be associated with a higher incidence of sinusitis due to structural and functional alterations. So, the aim of this study was to assess the prevalence of nasal septal deviation (NSD), nasal septal spur (NSS) and nasal septal pneumatization (NSP) among the Saudi adult population and their links with the incidence of sinusitis by using computed tomography (CT). A retrospective study was achieved over a twenty-two months period on 681 adult Saudi subjects (420 males and 261 females) aged 20 years or older, referred for coronal CT evaluation of the paranasal sinuses. NSD and NSS were significantly more prevalent in males than females (80.0% vs. 67.4% respectively for NSD, and 34.5% vs. 24.9% respectively for NSS), while there was no statistical difference in frequency of NSP regarding gender (P=0.670). The incidence of sinusitis was significantly higher in presence of NSD and/or NSS (P<0.001 for both). On the contrary, NSP was not associated with a significant increase in the prevalence of sinusitis (P=0.131). In conclusion, NSD and NSS are more prevalent in males than females among the Saudi population with no statistical difference between both genders regarding the presence of septal pneumatization. Furthermore, sinusitis is more prevalent with the occurrence of NSD and NSS, and not related to the incidence of NSP.

Development of the Information Delivery System for the Home Nursing Service (가정간호사업 운용을 위한 정보전달체계 개발 I (가정간호 데이터베이스 구축과 뇌졸중 환자의 가정간호 전산개발))

  • Park, J.H;Kim, M.J;Hong, K.J;Han, K.J;Park, S.A;Yung, S.N;Lee, I.S;Joh, H.;Bang, K.S
    • Journal of Home Health Care Nursing
    • /
    • v.4
    • /
    • pp.5-22
    • /
    • 1997
  • The purpose of the study was to development an information delivery system for the home nursing service, to demonstrate and to evaluate the efficiency of it. The period of research conduct was from September 1996 to August 31, 1997. At the 1st stage to achieve the purpose, Firstly Assessment tool for the patients with cerebral vascular disease who have the first priority of HNS among the patients with various health problems at home was developed through literature review. Secondly, after identification of patient nursing problem by the home care nurse with the assessment tool, the patient's classification system developed by Park (1988) that was 128 nursing activities under 6 categories was used to identify the home care nurse's activities of the patient with CAV at home. The research team had several workshops with 5 clinical nurse experts to refine it. At last 110 nursing activities under 11 categories for the patients with CVA were derived. At the second stage, algorithms were developed to connect 110 nursing activities with the patient nursing problems identified by assessment tool. The computerizing process of the algorithms is as follows: These algorithms are realized with the computer program by use of the software engineering technique. The development is made by the prototyping method, which is the requirement analysis of the software specifications. The basic features of the usability, compatibility, adaptability and maintainability are taken into consideration. Particular emphasis is given to the efficient construction of the database. To enhance the database efficiency and to establish the structural cohesion, the data field is categorized with the weight of relevance to the particular disease. This approach permits the easy adaptability when numerous diseases are applied in the future. In paralleled with this, the expandability and maintainability is stressed through out the program development, which leads to the modular concept. However since the disease to be applied is increased in number as the project progress and since they are interrelated and coupled each other, the expand ability as well as maintainability should be considered with a big priority. Furthermore, since the system is to be synthesized with other medical systems in the future, these properties are very important. The prototype developed in this project is to be evaluated through the stage of system testing. There are various evaluation metrics such as cohesion, coupling and adaptability so on. But unfortunately, direct measurement of these metrics are very difficult, and accordingly, analytical and quantitative evaluations are almost impossible. Therefore, instead of the analytical evaluation, the experimental evaluation is to be applied through the test run by various users. This system testing will provide the viewpoint analysis of the user's level, and the detail and additional requirement specifications arising from user's real situation will be feedback into the system modeling. Also. the degree of freedom of the input and output will be improved, and the hardware limitation will be investigated. Upon the refining, the prototype system will be used as a design template. and will be used to develop the more extensive system. In detail. the relevant modules will be developed for the various diseases, and the module will be integrated by the macroscopic design process focusing on the inter modularity, generality of the database. and compatibility with other systems. The Home care Evaluation System is comprised of three main modules of : (1) General information on a patient, (2) General health status of a patient, and (3) Cerebrovascular disease patient. The general health status module has five sub modules of physical measurement, vitality, nursing, pharmaceutical description and emotional/cognition ability. The CVA patient module is divided into ten sub modules such as subjective sense, consciousness, memory and language pattern so on. The typical sub modules are described in appendix 3.

  • PDF

An Evaluation Model on Supply Factors of Urban Park (도시공원의 공급인자 평가모형)

  • Chang, Byung-Moon
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.38 no.1
    • /
    • pp.1-11
    • /
    • 2010
  • The purpose of this paper is to evaluate supply factors of urban parks to answer the research question: What are the causal effects of supply factors of urban parks on visitor satisfaction? After reviewing the literature and the Korean park planning process, we constructed a conceptual framework and have formulated the hypothesis of this research. We had obtained data through a questionnaire, which surveyed 452 visitors at 8 urban parks in Daegu Metropolitan City in 2008, based on a stratified sampling method. After the elimination of 96 unsuitable samples, we have analyzed the data using descriptive statistical methods, Pearson's correlation analysis and a path analysis method. We have found that: 1) While the direct and indirect effect of accessibility(ACC) on visitor satisfaction(VS) turned out to be 0.184 and 0.220, respectively, the indirect effect of information(IFM) and promotion(PRM) on VS turned out to be 0.101 and 0.177, respectively. 2) While the direct and indirect effect of service(SVR) on VS turned out to be 0.130 and 0.236, respectively, the direct effect of ACC turned out to be 0.698. 3) While the direct effect of ACC, SVR and attraction(ATT) on VS turned out to be 0.184, 0.130 and 0.698, respectively, composing 67.96% of causal effect, the indirect effect of ACC, IFM, PRM and SVR on VS turned out to be 0.220, 0.101, 0.177 and 0.236, respectively, composing 42.04% of causal effect. 4) The magnitude of causal effect of supply factors on VS turned out to be ATT(39.98%), ACC(23.14%), SVR(20.96%), PRM(10.14%) and IFM(5.78%) in order, and 5) the causal effect of external supply factors of ACC, IFM and PRM compose 39.06% of the causal effect while that of the internal supply factors of SVR and ATT is 69.94%. The research results suggest that: 1) Planning for park marketing strategy and remedial directions for existing urban parks, in order to increase visitor satisfaction, be focused on IFM and PRM, especially. 2) The research approach and path analysis method adopted by this research be valid and highly useful for planning and evaluation of other recreation areas. It is recommended that: 1) Structural Equation Model on supply factors of urban parks be established in the future. 2) Evaluation of supply factors by type of urban park be performed.

A Study on the Designer's Post-Evaluation of Gyeongui Line Forest Park Based on Ground Theory - Focused on Yeonnam-dong Section - (근거이론을 활용한 설계자의 경의선숲길공원 사후평가 - 연남동 구간을 중심으로 -)

  • Kim, Eun-Young;Hong, Youn-Soon
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.47 no.3
    • /
    • pp.39-48
    • /
    • 2019
  • This research is based on the analysis of in-depth interviews of designers who participated in the design of the Yeonnam-dong section, which was completed in 2016. The case study site has received many domestic and foreign awards and is receiving very positive reviews from actual users. 53 concepts were derived from the open coding of the ground theory methodology. Thirty-four higher categories incorporated the concepts and 18 higher categories that reintegrated them. Later, the six categories of the ground theory were interpreted as the paradigm, and it was determined that the aspects of 'will of client' and 'work efficiency', 'site resources' and 'field manager's specialty' were the categories that had the greatest positive impact on the park construction. The key category of this park's construction was interpreted as "a park-construction model with active empathy and communication." The results of the study and are linked to the following research proposals. First, the need to improve the trust between the client and the landscape designer and the need to improve the customary administrative procedures; second, the importance of the input of landscape experts into the park construction process; third, the importance of all efforts to develop the design; fourth, the importance of on-site circular resources and landscape preservation; and fifth active social participation to increase the opportunity. This study, which seeks to grasp the facts that existed behind the park's construction, which received excellent internal and external evaluations, and has a qualitative, objective and structural interpretation of the social network related to the park's construction, in contrast to the conventional quantitative post-evaluation. It is expected that the administration and system improvements related to landscaping will be further improved through the continuation of in-depth post-evaluation studies.

Development of an evaluation tool for dietary guideline adherence in the elderly (노인의 식생활지침 실천 평가도구 개발)

  • Young-Suk Lim;Ji Soo Oh;Hye-Young Kim
    • Journal of Nutrition and Health
    • /
    • v.57 no.1
    • /
    • pp.1-15
    • /
    • 2024
  • Purpose: This study aimed to develop a comprehensive tool for assessing dietary guideline adherence among older Korean adults, focusing on the domains of food and nutrient intake, eating habits, and dietary culture. Methods: Candidate items were selected through a literature search and expert advice. The degree of adherence to dietary guidelines was then evaluated through a face-to-face survey conducted on 800 elderly individuals across five nationwide regions. The items for dietary guideline adherence evaluation tool were selected through exploratory factor analysis of the candidate items in each of the three areas of the dietary guidelines, and construct validity was verified by performing confirmatory factor analysis. Using the path coefficient of the structural equation model, weights were assigned to each area and item to calculate the dietary guideline adherence score. A rating system for the evaluation tool was established based on national survey results. Results: A total of twenty-eight items were selected for evaluating dietary guideline adherence among the elderly. Thirteen items related to food intake, seven to eating habits, and eight to dietary culture. The average score for dietary guideline adherence was 56.9 points, with 49.8 points in the food intake area, 63.2 points in the eating habits area, and 58.6 points in the dietary culture area. Statistically significant correlations were found between dietary guideline adherence scores and food literacy (r = 0.679) and nutrition quotient scores (r = 0.750). Conclusion: The developed evaluation tool for dietary guideline adherence among Korean older adults can be used as a simple and effective instrument for comprehensively assessing their food and nutrient intake, dietary habits, and dietary culture.