• Journal of Information Technology Services
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• v.15 no.4
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• pp.153-174
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• 2016

On account of multiple causes, including prolonged global economic crisis, addressing environmental pollution and the advent of hyper-connected society, a new paradigm called 'sharing economy' has rapidly emerged. Many startups have attempted to build promising business model based on the sharing economy concept. Nevertheless, successful cases are still very rare in the global level, except for Uber and Airbnb cases. Therefore, this study analyzes necessary causes and sufficient causes for successful settlements in the market through a comparative case analysis on digital matching firms in the sharing economy businesses. For the case study, we compare five successful cases (Uber, Airbnb, Kickstarter, TaskRabbit and DogVacay), three failure cases (Homejoy, Ridejoy and Tuterspree) and a platform cooperativism case (Juno) in accordance with six value attributes of business model including value proposition, market segment, value chain, cost structure and profit potential, value network and competitive strategy. We apply Boolean method to support controlled comparison and eliminate unnecessary attributes. The Boolean analysis result shows that value proposition, cost structure and profit potential, value network and competitive strategy are the essential attributes. Furthermore, the result indicates that each attribute is a necessary condition, where all four conditions should be met simultaneously in order to be successful. With this result, we discuss essential consideration for those who are planning startup based on the sharing economy business model.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.1
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• pp.44-51
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• 2007

The purpose of this study was to identify the relationship between the cumulative fatigue of trunk muscles andthe period of recovery time during repetitive lifting and lowering tasks with symmetric and asymmetric postures.Ten subjects participated in the experiment. Subjects had 1, 2, 3, 4 and 5 minutes recovery time respectivelywhile they were performing the lifting and lowering task repeatedly for 3 minutes with the weight equivalent to25% level of MVC. EMG signals from ten trunk muscles were collected and the fatigue level was analyzedquantitatively. In results, the local muscle fatigue was no longer accumulated when 5 minutes recovery time wasgiven in symmetric position. For asymmetric position, it took longer minutes to prevent the fatigue accumul-ation. Different trunk muscles indicated slightly different recovery patterns in terms of MPF (Mean Powerfrequency) value.This result would help ergonomist design the length of recovery time to control the cumulative fatigue of trunkmuscles in industry with repetitive lifting and lowering task.

• Korean Journal of Human Ecology
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• v.7 no.1
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• pp.97-108
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• 1998

The purpose of this study was to examine the family resources, stress level, and coping strategies of reemployed wives, to direct the better psycho-physical environment, and to enhance the quality of their home environment for reemployed wives. The data were analyzed with the frequency, percentage, factor analysis, mean(S.D), reliability, and regression using SPSS windows program. The major findings were as follows : (1) There were significant relationships between demographic and socioeconomic characteristics of the family resources and stress level. Personal-psycho resources was important variable in the family resources. The household work and value of household work were most influential. (2) Influential variables on stress level were income and working hours, resources of family task sharing. (3) Influential variables on coping strategies were age, reemployed time, and family task sharing. Coping strategies was effected by the reasons of employment.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.123-131
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• 2002

Recently our government operates earned value management system (EVMS) for improving work management system of the construction projects over specific scale. The EVMS is based on the integrated management between construction cost and schedule, the existing systems, however, are focused on the cost management by using wort quantity. This study suggests a work management mode1 to integrate construction cost with activity information. The model introduces a work task concept as a tool that can connect construction cost to activity information. The suggested model in this study is verified by using actual data for the applicability to practical construction projects.

• Publications of The Korean Astronomical Society
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• v.9 no.1
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• pp.39-54
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• 1994

We present two codes which estimates virial mass and LTE mass using IMFORT interface within IRAF (Image Reduction and Analysis Facility). It is discussed that threshold value (temperature or CO integrated intensity), which defines a reasonable cloud boundary and size, is the most important parameter determining accurate results. Several virial masses are to be obtained using the vir task, as well as three velocity dispersions including the centroid velocity dispersion, a turbulence indicator. LTE mass is to be estimated by using task lte as well as three by-product images. The $^{13}CO$ abundance and threshold temperature of $^{13}CO$ and $^{12}CO$ peak temperatures are the most critical parameters in LTE technique.

• Journal of the Korea Institute of Building Construction
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• v.2 no.4
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• pp.153-161
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• 2002

Recently our government operates earned value management system (EVMS) for improving work management system of the construction projects over specific scale. The EVMS is based on the integrated management between construction cost and schedule. the existing systems, however, are focused on the cost management by using work quantity. This study suggests a work management model to integrate construction cost with activity information. The model introduces a work task concept as a tool that can connect construction rest to activity information. The suggested model in this study is verified by using actual data for the applicability to practical construction projects.

• The Journal of Korea Robotics Society
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• v.17 no.2
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• pp.164-171
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• 2022

Recently, interest of a dual arm robot which can replace humans is increasing in order to improve the working environment and solve the labor shortage. Various studies related with design and analysis of dual-arm robots have been conducted because dual arm robots can have various kinematic configurations according to the objective task. It is necessary to evaluate the work performance according to various kinematic structures of the dual arm robot to maximize its effectiveness. In the paper, the performance analysis is studied according to the shoulder configuration and the wrist configuration of the dual-arm robot by using main performance indices such as manipulability, condition number, and minimum singular value by assigning proper weight values to each objective motion. Performance analysis for the robotic assembly process is effectively carried out for each representative dual arm robot configuration.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2020.11a
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• pp.25-28
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• 2020

Automatic segmentation of brain tissues such as WM, GM, and CSF from brain MRI scans is helpful for the diagnosis of many neurological disorders. Accurate segmentation of these brain structures is a very challenging task due to low tissue contrast, bias filed, and partial volume effects. With the aim to improve brain MRI segmentation accuracy, we propose an end-to-end convolutional based U-SegNet architecture designed with multi-scale kernels, which includes cascaded dilated convolutions for the task of brain MRI segmentation. The multi-scale convolution kernels are designed to extract abundant semantic features and capture context information at different scales. Further, the cascaded dilated convolution scheme helps to alleviate the vanishing gradient problem in the proposed model. Experimental outcomes indicate that the proposed architecture is superior to the traditional deep-learning methods such as Segnet, U-net, and U-Segnet and achieves high performance with an average DSC of 93% and 86% of JI value for brain MRI segmentation.

• The Journal of the Korea Contents Association
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• v.11 no.7
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• pp.306-315
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• 2011

The study defines the job characteristics anxiety of the private security workers and the effect of the performance. While the study selected the private guards working at the private security companies registered at the National Police Agency in Seoul 2011 and sampled total 300 people by using the judgment sampling method, the final input case number is 266 people. The study used alpha value of the reliability analysis and the maximum-likelihood classification of the covariation structure analysis in order to verify the validity of the survey and the reliability. With the research method and the process the result of the study is as follows. First, the task importance of the private security workers affects the minus influence to the characteristic anxiety. Second, the feedback of the private security workers affects the minus influence to the characteristic anxiety. Third, the job autonomy of the private security workers affects the minus influence to the characteristic anxiety. Fourth, the feedback of the private security workers affects the plus influence to the task performance. Fifth, the job autonomy of the private security workers affects the plus influence to the task performance. Sixth, the skill variety of the private security workers affects the plus influence to the task performance. Seventh, the characteristic anxiety of the private security workers affects the plus influence to the task performance.

• Journal of Korean Academy of Nursing Administration
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• v.9 no.2
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• pp.159-170
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• 2003

Purpose : This study is to confirm the relation of the value orientation of the nursing unit manager and the job satisfaction and organizational commitment of the nursing unit nurse. Method : We used the systematic questionnaires as a study tool. The contents were composed of 46 questions in total such as 4 questions of general feature, 23 value-oriented questions, 10 job satisfaction questions, and 9 organizational commitment questions. The period of data collection was from August to September 2000. Result : 1) The value of flexibility was 3.82 points (${\pm}.3788$), which is above average. The values of equalitarianism was 3.37 points (${\pm}.4422$), which is above average. 2) The leadership pattern according to the value orientation perceived by the head nurses in 6 clusters has been divided into 3 patterns of change-oriented leader, task-oriented and stability-oriented leader. 3) The nurses who worked with the change-oriented leader showed higher values of job satisfaction (F=5.941, p=O.003), and affective commitment (F=5.793, p=O.003) than those who worked with the stability-oriented leader. Conclusion : As revealed in this study, we think that we have to consider that the change-oriented leader can produce higher performance of an organization than the stability-oriented leader, and write the basic data for the educational courses of leadership development or workshops etc. in order for the nursing unit managers to play their roles for the effective ward-unit management.