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Effects of Child Welfare Service Quality Delivery and Customer Satisfaction from the Service Distribution Perspective (서비스 유통 관점에서 아동복지기관 서비스질의 전달에 대한 인식과 이용자 만족도에 미치는 영향)

  • Um, Keung-Ho;Kim, Jin-Woo
    • Journal of Distribution Science
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    • v.13 no.8
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    • pp.91-96
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    • 2015
  • Purpose - This study reviews the delivery of child welfare service quality and examines how the dimensions of the variables of customer satisfaction impact the results from a service distribution perspective. This study differs from existing research since it proposes that a recognized level of child welfare service quality is necessary to achieve customer satisfaction from the perspective of service distribution. Research design, data, and methodology - This study explores child welfare service quality factors that affect customer satisfaction. The study examines and analyzes demographic variables, service quality dimensions, and the causal relationships between child welfare service quality and customer satisfaction. Data from 300 child welfare cases were collected from organizations in Korea in the areas of Busan and Gyeongsangnamdo. The methods of analysis are as follow. First, using descriptive analysis frequency, the percentages were evaluated to assess the demographic variables. Second, Cronbach's α was used to test reliability and to evaluate the internal consistency of the measuring of items. Third, multiple regression analysis was conducted to find out how much the independent variable can affect customer satisfaction. Results - Five factors of child welfare service quality were identified in three categories: process quality (assurance, empathy), results quality (reliability, caring), and physical environment quality (tangibles). There were significant differences among the effects of the child welfare service quality factors on customer satisfaction. A multiple regression analysis was done with process quality (assurance, empathy), results quality (reliability, caring) and physical environment quality (tangibles) to test the hypothesis: assurance (t=2.434, p<0.05), empathy (t=3.677, p<0.001), reliability (t=3.271, p<0.05), caring (t=4.380, p<0.000), and tangibles (t=3.654, p<0.01) had a positive influence on child welfare service quality from a service distribution perspective. Therefore, hypotheses 1, 2, 3, 4, and 5 were supported. In addition, multiple regression analysis on the effects of the variables showed that caring (β=0.273), empathy (β=0.246), tangibles (β=0.265), reliability (β=0.152), and assurance (β=0.131) all had a positive and strong influence on child welfare service quality from a service distribution perspective. Therefore, all child welfare service quality categories (process, results and physical environment quality) were positively statistically significant. Conclusion - In this study, the main findings can be summarized as follows. First, the quality of service of child welfare consists of three dimensions of quality: process quality, results quality, and physical environment quality. The results of the multiple regression analysis also showed that caring and reliability were confirmed as more meaningful variables by the increasing loading factors. Second, the family members involved in child welfare proposed caring as the most important variable among the dimensions of service quality. Third, the results of the hypothesis testing using regression showed that all child welfare service quality factors had a positive impact on customer satisfaction. The results of the study could provide useful information to help increase the effectiveness of delivery strategies for child welfare service quality from a service distribution perspective.

A methodology for assessing fatigue life of a countersunk riveted lap joint

  • Li, Gang;Renaud, Guillaume;Liao, Min;Okada, Takao;Machida, Shigeru
    • Advances in aircraft and spacecraft science
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    • v.4 no.1
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    • pp.1-19
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    • 2017
  • Fatigue life prediction of a multi-row countersunk riveted lap joint was performed numerically. The stress and strain conditions in a highly stressed substructure of the joint were analysed using a global/local finite element (FE) model coupling approach. After validation of the FE models using experimental strain measurements, the stress/strain condition in the local three-dimensional (3D) FE model was simulated under a fatigue loading condition. This local model involved multiple load cases with nonlinearity in material properties, geometric deformation, and contact boundary conditions. The resulting stresses and strains were used in the Smith-Watson-Topper (SWT) strain life equation to assess the fatigue "initiation life", defined as the life to a 0.5 mm deep crack. Effects of the rivet-hole clearance and rivet head deformation on the predicted fatigue life were identified, and good agreement in the fatigue life was obtained between the experimental and the numerical results. Further crack growth from a 0.5 mm crack to the first linkup of two adjacent cracks was evaluated using the NRC in-house tool, CanGROW. Good correlation in the fatigue life was also obtained between the experimental result and the crack growth analysis. The study shows that the selected methodology is promising for assessing the fatigue life for the lap joint, which is expected to improve research efficiency by reducing test quantity and cost.

In-Plane Collision Analysis of Perforated Steel Plates (면내 충돌에 의한 유공 강판의 거동 해석)

  • Kang, Dong-Baek;Lee, Ju-Won;Na, Won-Bae;Kim, Jeong-Tae
    • Journal of Ocean Engineering and Technology
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    • v.22 no.4
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    • pp.65-71
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    • 2008
  • In many cases, open-type plate breakwaters use plates with multiple holes; the holes serve as energy dissipaters and weight reducers. Because of the multi-holes configuration, stress concentration should be considered during the design process. Among several design loading conditions, the loads from a possible collision with a man-made vessel or other unexpected events many damage a multi-perforated steel plate. In that case, the structural behavior of a multi-perforated steel plate is quite significant, and is not well understood. This study presents a collision analysis for a multi-perforated steel plate. First, four different perforation topologies (three with circles and one with squares) were selected to investigate the effect of different hole shapes on the structural response. Second, the wave force at a specific site was calculated and loaded onto a steel plate as a static load. The static stresses were used for reference values. Third, two rigid body impacters (cubical & cylindrical) were applied to the steel plates to investigate the transient stress responses. In addition, two different impacting angles ($45^{\circ}\;&\;90^{\circ}$) were selected to investigate the angle effect. From the collision analysis, the significance of the transient stresses was emphasized.

Initial Experiences of Extracorporeal Membrane Oxygenation for Trauma Patients at a Single Regional Trauma Center in South Korea

  • Ko, Ji Wool;Park, Il Hwan;Byun, Chun Sung;Jang, Sung Woo;Jun, Pil Young
    • Journal of Trauma and Injury
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    • v.34 no.3
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    • pp.162-169
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    • 2021
  • Purpose: For severe lung injuries or acute respiratory distress syndrome that occurs during critical care due to trauma, extracorporeal membrane oxygenation (ECMO) may be used as a salvage treatment. This study aimed to describe the experiences at a single center with the use of ECMO in trauma patients. Methods: We enrolled a total of 25 trauma patients who were treated with ECMO between January 2015 and December 2019 at a regional trauma center. We analyzed and compared patients' characteristics between survivors and non-survivors through a medical chart review. We also compared the characteristics of patients between direct and indirect lung injury groups. Results: The mean age of the 25 patients was 45.9±19.5 years, and 19 patients (76.0%) were male. The mean Injury Severity Score was 26.1±10.1. Ten patients (40.0%) had an Abbreviated Injury Scale (AIS) 3 score of 4, and six patients (24.0%) had an AIS 3 score of 5. There were 19 cases (76.6%) of direct lung injury. The mortality rate was 60.0% (n=15). Sixteen patients (64.0%) received a loading dose of heparin for the initiation of ECMO. There was no significant difference in heparin use between the survivors and non-survivors (70% in survivors vs. 60% in non-survivors, p=0.691). When comparing the direct and indirect lung injury groups, there were no significant differences in variables other than age and ECMO onset time. Conclusions: If more evidence is gathered, risk factors and indications will be identified and we expect that more trauma patients will receive appropriate treatment with ECMO.

Characterization of the wind-induced response of a 356 m high guyed mast based on field measurements

  • Zhe Wang;Muguang Liu;Lei Qiao;Hongyan Luo;Chunsheng Zhang;Zhuangning Xie
    • Wind and Structures
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    • v.38 no.3
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    • pp.215-229
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    • 2024
  • Guyed mast structures exhibit characteristics such as high flexibility, low mass, small damping ratio, and large aspect ratio, leading to a complex wind-induced vibration response mechanism. This study analyzed the time- and frequency-domain characteristics of the wind-induced response of a guyed mast structure using measured acceleration response data obtained from the Shenzhen Meteorological Gradient Tower (SZMGT). Firstly, 734 sets of 1-hour acceleration samples measured from 0:00 October 1, 2021, to 0:00 November 1, 2021, were selected to study the vibration shapes of the mast and the characteristics of the generalized extreme value (GEV) distribution. Secondly, six sets of typical samples with different vibration intensities were further selected to explore the Gaussian property and modal parameter characteristics of the mast. Finally, the modal parameters of the SZMGT are identified and the identification results are verified by finite element analysis. The findings revealed that the guyed mast vibration shape exhibits remarkable diversity, which increases nonlinearly along the height in most cases and reaches a maximum at the top of the tower. Moreover, the GEV distribution characteristics of the 734 sets of samples are closer to the Weibull distribution. The probability distribution of the structural wind vibration response under strong wind is in good agreement with the Gaussian distribution. The structural response of the mast under wind loading exhibits multiple modes. As the structural response escalates, the first three orders of modal energy in the tower display a gradual increase in proportion.