• Journal of the Microelectronics and Packaging Society
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• v.8 no.2
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• pp.37-42
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• 2001

The BGA package has been the area array package of choice for several years. Recently, the transition has been to finer pitch configurations called Chip Scale Packages (CSP). Several of these package types are available at 0.5 mm pitch. requiring surface mount assemblers to evaluate and optimize various elements of the assembly process. This presentation describes the issues associated with making the transition from BGA to CSP assembly. Areas addressed will include the accuracy of pick and place equipment, printed wiring board lines and spaces, PWB vias, in-circuit test issues, solder paste printing, moisture related factors, rework and reliability. The transition to 0.5 mm pitch requires careful evaluation of the board design, solder paste selection, stencil design and component placement accuracy. At this pitch, ball and board pad diameters can be as small as 0.25 mm and 0.20 mm respectively. Drilled interstitial vias are no longer possible and higher ball count packages require micro-via board technology. The transition to CSP requires careful evaluation of these issues. Normal paste registration and BGA component tolerances can no longer achieve the required process levels and higher accuracy pick and place machines need to be implemented. This presentation will examine the optimization of these critical assembly operations, contrast the challenges at 0.5 mm and also look at the continuation of the process to incorporate smaller pitch flip chip devices.

• Korean Journal of Adult Nursing
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• v.16 no.3
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• pp.366-377
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• 2004

Purpose: This study is a descriptive research study to develop the Nurse's Humor Questionnaire, and then analyze humor's appreciation and use by Korean nurses. Method: The three stages used to develop the questionnaire were to make a conceptual framework, make an open questionnaire through the 2nd preliminary inquiry, and make a structured questionnaire based on collected statements through the developed open questionnaire. The subjects that carried out completely a structured questionnaire were 337 nurses. Result: 1) The final developed questionnaire consists of 6 domains and 67 items. The reliability of 'When feeling humor's expression'(${\alpha}=0.7079$), 'The barrier factors of humor's use'(${\alpha}=0.7895$), and 'Humor's values' (${\alpha}=0.8336$) was high. 2) The results related to Humor's values of nurses that showed significant differences were as follow: (1) age, marital status, and current position (2) a negative correlation between stress and humor's values (3) humor's sources: daily life and conversation (4) frequency of used humor (5) types of used humor: word humor, imitation, adequate situation and technical terms, and (6) when using humor's expression: tense atmosphere, awkward atmosphere and adequate situation. Conclusion: The developed tool can be used for understanding nurse's humor. This will help to develop the humor program as a nursing intervention for health promotion.

• Korean Journal of Adult Nursing
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• v.26 no.5
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• pp.512-521
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• 2014

Purpose: This study examined the effect of work environment and job satisfaction on service quality among staff caring for the elderly. Methods: A convenient sample was 192 staff members from 95 elderly facilities. Data collection occurred from June to July, 2011 using a self-administered questionnaire. Data was analyzed using SPSS/WIN 18.0. Results: Among the subscales of Work Environment Scale, the self-realization score was the highest followed by workload, nervousness, and conflict. The mean score of job satisfaction was 71.43. Reliability was the highest followed by assurance, empathy, responsiveness, and tangibles. Predictive factors of service quality included self-realization work environment and job satisfaction. Conclusion: Exploration of strategies to improve the recognition of self-realization work environment and job satisfaction will be necessary in order to increase of service quality among staffs in elderly facility.

• Journal of Welding and Joining
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• v.9 no.3
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• pp.41-51
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• 1991

The thermomechanical coupling phenomena in the resistance welding process is complicated due to interactions of mechanical, thermal and electrical factors. Although experimental investigations of resistance spot welding have been carried out, but there are a few by computer simulation. so the purpose of this research is to decrease the time and cost much required in experimental investigation by carrying out the analysis of the resistance spot welding process through computer simulation based on the finite element method. The tool used in the computer simulation is the commercial ANSYS program package. A two dimensional axisymetric model is used to simulate the resistance spot welding for two stainless steel sheets of equal thickness and parametric study is carried out for variable welding current, workpieces of unequal thickness and dissimilar materials. The results from the computer simulation are in good agreement with the experimental one. Through these results, such items as stress distribution, temperature profiles, thermal expansion and weld nugget formation are predicted. Reliability and applicability of finite element models have been demonstrated to simulate and to analyze the resistance spot welding process.

• Journal of Families and Better Life
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• v.27 no.2
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• pp.11-28
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• 2009

This study is intended to make a tool which can identify how consumers consume by presenting a concept of "consumption style" and by developing the scale to measure it. In order to study the scope and meaning of consumption for modern consumers, "the meaning of consumption" was theoretically considered. Based on it, the concept and perspective of 'consumption style'was formed and then the scale for measuring it was developed. To develop the scale, the scale was formed by extracting questions through a literature survey, and verifying validity through experts' opinion. Then, the final scale was developed by conducting a questionnaire survey for consumers. A preliminary 150- item scale was developed through a literature review. 1000 consumers responded to an online survey using the preliminary scale. This research was made with the intention of not only supplying the academic data on the consumer's "consumption style" but also understanding the consumer's basic behavior patterns. Then A series of tests, such as test-retest, item-to-total correlation, Cronbach's reliability coefficient and factor analysis, were conducted using the survey data. The final scale with 68-items was constructed in the end. The "consumption style" Scale for Consumers consisted of 4 factors.

• Journal of Radiation Protection and Research
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• v.29 no.1
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• pp.41-48
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• 2004

A safety assessment code, called SAGE (Safety Assessment Groundwater Evaluation), has been developed to describe post-closure radionuclide releases and potential radiological doses for low- and intermediate-level radioactive waste (LILW) disposal in an engineered vault facility in Korea. The conceptual model implemented in the code is focused on the release of radionuclide from a gradually degrading engineered barrier system to an underlying unsaturated zone, thence to a saturated groundwater zone. The radionuclide transport equations are solved by spatially discretizing the disposal system into a series of compartments. Mass transfer between compartments is by diffusion/dispersion and advection. In all compartments, radionuclides ate decayed either as a single-member chain or as multi-member chains. The biosphere is represented as a set of steady-state, radionuclide-specific pathway dose conversion factors that are multiplied by the appropriate release rate from the far field for each pathway. The code has the capability to treat input parameters either deterministically or probabilistically. Parameter input is achieved through a user-friendly Graphical User Interface. An application is presented, which is compared against safety assessment results from the other computer codes, to benchmark the reliability of system-level conceptual modeling of the code.

• Korean Journal of Occupational Health Nursing
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• v.20 no.2
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• pp.153-162
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• 2011

Purpose: The purpose of this study is to investigate the impact of job stress, self-efficacy and empowerment of 119 Emergency medical technicians in Jeollanam-do. Methods: This study used the data collected from 346 respondents working for first aid in a fire station. To answer research questions, this study employed frequency analysis, reliability test, F (t)-test, ANOVA, Scheffe' post-hoc test, and multiple-regression analysis. Results: In terms of demographic characteristics, marital status and age had significant impact on job stress, but sex and education did not. In terms of job characteristics, first placement, rank, and tenure made significant difference on job stress, whereas certificate, department, and area did not. These results address that general characteristics, self-efficacy and job stress are critical variables on empowerment. Conclusion: From the research findings, it is concluded that fire fighters' job stress can be reduced if professional development programs are given to them, which is likely to provide better public services such as first aids and welfare, as well as to increase job satisfaction.

• Research in Community and Public Health Nursing
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• v.30 no.4
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• pp.471-483
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• 2019

Purpose: The purpose of this study was to identify factors associated with the intention of the prostate cancer screening (PCS). To achieve this purpose, a structural equation model was established based on the health belief model and the theory of planned behavior. Methods: The subjects of this study were 260 male participants who were between 40 and 74 years old and had not taken the PCS. Data were collected using a structured self-report questionnaire (i.e., perceived benefits, perceived barriers, attitude, subjective norms, perceived behavior control, and intention of the PCS). Descriptive statistics, reliability analysis, correlation analysis, confirmatory factor analysis, and fitness test were used to test hypotheses. Results: The intention of the PCS was directly affected by the perceived behavior control and indirectly influenced by the perceived benefits. The structural equation model also showed that the perceived behavior control explained 78% of the intention. Conclusion: To raise the intention to take the PCS, it is necessary to increase the confidence of a subject that may control its difficulties and inform the perceived benefits of the PCS to a subject.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.173-174
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• 2009

With the recent emergence of high rise buildings, this study was conducted in order to examine shortening, which has been used only in civil engineering structures, in such buildings. Examination of the shortening of vertical members is basically focused on deformations caused by load applied to concrete, material characteristics, etc. Shortening is analyzed through calculating parameters from the factors or characteristics of concrete, but analysis in the aspect of material tests has been somewhat unsatisfactory. Thus, this study purposed to analyze basic material test items for correcting the shortening of vertical members, namely, columns, to determine the reliability of material tests before parameter calculation for correcting shortening, and to examine the performance of material tests.

• Journal of Ocean Engineering and Technology
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• v.24 no.6
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• pp.103-108
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• 2010

WIG crafts are high speed vessels with the features of a dynamic supported craft. These crafts, which are predominantly lightweight and operate at substantially greater speeds than conventional craft, could not be accommodated under traditional maritime safety instruments. WIG crafts inherently possess more hazard factors than conventional ships because of their relatively high speed, lightweight, and navigational characteristics, and an accident is likely to cause damage to the ship and a high loss of life. Because WIG crafts are composed of many systems and subsystems, the safety assessment of a WIG must use a commercial software system in the design stage. This paper reviews a safety assessment process and methodology proposed by the IMO interim guideline, which were developed in view of the configuration of WIG crafts. This safety assessment system was developed to fit the WIG's safety assessment process using a reliability analysis system widely used in commercial systems. The FHA was performed on the functional hazards of systems in the conceptual design stage.