• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.7
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• pp.1935-1950
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• 2023

The arrival of the Internet of Things and 5G technology enables users to rely on edge computing platforms to process massive data. Data sharing based on edge computing refines the efficiency of data collection and analysis, saves the communication cost of data transmission back and forth, but also causes the privacy leakage of a lot of user data. Based on attribute-based encryption and blockchain technology, we design a fine-grained access control scheme for data in edge computing, which has the characteristics of verifiability, support for outsourcing decryption and user attribute revocation. User attributes are authorized by multi-attribute authorization, and the calculation of outsourcing decryption in attribute encryption is completed by edge server, which reduces the computing cost of end users. Meanwhile, We implemented the user's attribute revocation process through the dual encryption process of attribute authority and blockchain. Compared with other schemes, our scheme can manage users' attributes more flexibly. Blockchain technology also ensures the verifiability in the process of outsourcing decryption, which reduces the space occupied by ciphertext compared with other schemes. Meanwhile, the user attribute revocation scheme realizes the dynamic management of user attribute and protects the privacy of user attribute.

• Journal of the Korean association of regional geographers
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• v.9 no.4
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• pp.505-518
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• 2003

The purpose of this paper is to review Post-Fordist urban economic theories that have tackled the recent changes of urban economies in large cities in the world since 1980s, so that we can conceptualise the changes of urban economies in Korean cities. In the perspective of the Post-Fordist urban economic theories, the recent changes of urban economies in the world are deeply related to the transformation of capitalist world economic system from Fordism to Post-Fordism. To see these changes which can be called as the new urbanization process in the economic aspect, we will focus especially such theories as new industrial space (district) theory based on the flexible specialization paradigm, informational city theory based on the information and communication mode paradigm, and cluster and regional innovation theory based on the institution and network paradigm. Also we will consider the social polarization process and dual city phenomena that have been observed for the most part of big cities in the world.

• The Journal of the Korea Contents Association
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• v.18 no.2
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• pp.592-601
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• 2018

The purpose of this study is to investigate the relationship among empathy ability, gratitude tendency, helping behavior, and happiness of college students and whether gratitude tendency and help behaviors are mediators in the relationship between empathy ability and happiness. For this purpose, Date were collected from 559 college students in S and K city. The SPSS 20.0 program was used to analyze the statistical data such as the mean and standard deviation of the data. To analyze the validity of the study, it conducted confirmatory factor analysis using AMOS. Finally, we analyzed the effect of empathy on happiness by using the bootstrap procedure in order to investigate the mediating effects of gratitude tendency and helping behavior. The results of the study are as follows. First, the correlation of each was positive. Second, in the relationship between empathy ability and happiness, the gratitude tendency was a statistically significant mediator. Third, helping behavior was a statistically significant mediator between empathy and happiness. Fourth, in the relationship between empathy ability and happiness, it did not do dual mediate to the gratitude tendency and help behavior. The implications and limitations of this study are discussed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.2
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• pp.153-163
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• 2005

This paper presents two case studies for tunnelling in Bangkok: a subway tunnel site and a flood diversion tunnel site. The first case study is related to ground displacement response for dual tunnel Bangkok MRT subway. The MRT subway project of Bangkok city consists of dual tunnels about 20 km long with 18 subway stations. The tunnels are seated in the firm first stiff silty clay layer between 15-22 m in depth below ground surface. The behavior of ground deformation response based on instrumentation is presented. The back analysis based on plain strain FEM analysis is also presented and agrees with field performance. The shear strain of FEM analysis is in the range of 0.1-1% and in accordance with the results of self boring pressuremeter tests. Meanwhile, the second case study is related to the EPB tunnelling bored underneath through underground obstruction. The Premprachakorn flood diversion tunnel is the shortcut tunnel to divert the flood water in rainy season into the Choapraya river. The tunnel was bored by means of EPB shield tunnelling in very stiff silty clay layer at about 20-24 m in depth. During flood diversion tunnel bored underneath the existing Bangkok main water supply tunnel and pile foundation of the bridge, instrumentation was monitored and compared with predicted FEM analysis. The prevention risk potential by means of predicting damage assessment is also presented and discussed.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.2
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• pp.29-43
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• 2019

The calibration of microscopic traffic simulation models has received much attention in the simulation field. Although no standard has been established for it, a genetic algorithm (GA) has been widely employed in recent literature because of its high efficiency to find solutions in such optimization problems. However, the performance still falls short in simulation analyses to support fast decision making. This paper proposes a new calibration procedure using a dual GA and central composite design (CCD) in order to improve the efficiency. The calibration exercise goes through three major sequential steps: (1) experimental design using CCD for a quadratic response surface model (RSM) estimation, (2) 1st GA procedure using the RSM with CCD to find a near-optimal initial population for a next step, and (3) 2nd GA procedure to find a final solution. The proposed method was applied in calibrating the Gipps car-following model with respect to maximizing the likelihood of a spacing distribution between a lead and following vehicle. In order to evaluate the performance of the proposed method, a conventional calibration approach using a single GA was compared under both simulated and real vehicle trajectory data. It was found that the proposed approach enhances the optimization speed by starting to search from an initial population that is closer to the optimum than that of the other approach. This result implies the proposed approach has benefits for a large-scale traffic network simulation analysis. This method can be extended to other optimization tasks using GA in transportation studies.

• Korean Journal of Adult Nursing
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• v.22 no.6
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• pp.644-652
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• 2010

Purpose: The purpose of this study was to analyze the relationship among life style, body composition and Bone Mineral Density (BMD) in community dwelling Korean adults. Methods: Data were collected from 140 adults who participated in a health check-up program at community health departments in D city, Choong-chung providence. Subjects' life style was assessed with a structured interview survey. Body composition analyses were performed by the bioimpedence method and BMD was measured by peripheral dual energy X-ray absorptionmetry. Results: Among the subjects, 39.3% showed normal BMD values, 50.7% were osteopenic and 10% were assessed as osteoporotic. BMD was significantly different by gender, age, education, economic status and BMI. Subjects who had three or more meals/day had higher BMD then who had less than three meals (t=-2.273, p=.026). BMD was not influenced by regular exercise, alcohol consumption, or smoking. In terms of body composition, there was a significant relationship between fat free mass and BMD (r=.172, p=.043). Conclusion: Implementing an osteoporosis prevention program would be warrented considering the significant proportion of osteopenic or osteoporotic subjects. Regular eating habit with three meals for adequate nutrition need to be emphasized to prevent further bone loss in this population. Among the body composition, fat free mass seem to be the mostly predicting factor for BMD.

• Journal of the Korean association of regional geographers
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• v.8 no.2
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• pp.229-246
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• 2002

This study is a contribution to the geographical understanding of Daejeon Area, playing the role of principal center of Choongchong Province. This area has been urbanized associated with Daejeon Basin, an important natural unit in the middle part of South Korea. In order to understand Daejeon Area in geographer's view, it is necessary to elucidate geomorphological environment of Daejeon Basin and urban expansion pattern associating with it. Our research is converged into dual objectives: one, description and interpretation of basin's landforms; other, urban expansion relating with geomorphological condition. Daejeon's urban expansion has progressed from the border zone of Daejeon Basin toward into the basin, and then vice versa. Relating to rivers valleys in the basin, the urbanization in the basin has been extended from the river valleys of lower order toward those of higher order. Understanding of the geomorphological mosaique of Daejeon basin is an important base for that of urban mosaique of Daejeon City.

• Journal of Community Nutrition
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• v.6 no.3
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• pp.121-124
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• 2004

Objective : The paper aims to provide predictive coefficients via BIA for the assessment of body composition in children and adolescents to serve clinical as well as research purposes. Methods : Body composition via dual-energy x­ray absorptiometry (DXA) and bioelectric impedance as well as other anthropometric index were derived from meaurements on 1026 children and adolescents aged from 6 to 18 years from Beijing City. The best subset regression and principle component analysis were adopted to build the predictive coefficients with the logarithm of body composition via DXA as response variable. Results : Condition index ${\varphi}$ of fat-free mass multiple linear regression achieves 113.49 and 91.18 for males and females respectively, demonstrating severe multicollinearity among anthropometric indexes in children and adolescents. BIA predictive coefficients base on the best subset regression and principle component analysis boast a content predictive value for lean mass ($r^2$ = 0.9697 and 0.9664 for boys and girls respectively, p < 0.0001) and for Fat$\%$ ($r^2$ = 0.7705 and 0.6959 for boys and girls respectively, p < 0.0001). Conclusions : BIA method is applicable for the prediction of body composition for children and adolescents.

• Korean Architects
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• s.539
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• pp.70-75
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• 2014

This study strives to seek the background in Ho-Seo Bank(HQ)'s foundation and its urban meaning. First, the thesis intends to understand the autonomous characteristics of Ho-Seo Bank which had been supported by Korean capitalists(landowners and merchants), keeping their pure capitals acquired by regular traditional marketplaces and farming works around Yesan. Second, through quantification data, it deals with reasons that the Ho-Seo Bank have been situated on a triangular corner that meets three roads toward a main thoroughfare toward Gongju to Hongseong, a railroad station, and a downtown area(Honmachi(本町通)) each. Third, it discusses the subsequent changes of Yesan's urban landscape that resulted from the Ho-Seo Bank's foundation(1913). In other words, thanks to a newly founded Ho-Seo Bank's headquarter(1922) and partly opening of a railway(Gyeongnam, 1922), Yesan became more advanced constructing both a political venue for a military police, a county office, et cetera, and then an educational place for schools. In conclusion, such urban phenomena shows there would be a dual combination between Korean people(aboriginal landowners and intellectuals) in autonomous efforts and Japanese officials in heteronomous controls. This thesis further contends that Ho-Seo Bank architecture itself reflects their status in the locality, who envisioned a 'cultural equality,' competing with Japanese aggressors, and its firm and massive form shows a new building type of bank architecture, literally representing the safeness and firmness, so differentiated from other buildings with the 'Secession' style in colonial areas under the control of the world powers.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1718-1724
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• 2004

A station is not only the public space where socially diverse classes get together and cultural interchanges occur but also the personal and emotional space where the meeting and parting occur for each individual. Thus, it is necessity to consider this dual point from the beginning of the plan to make the simple, comfortable, intuitive and friendly environment for the users in the station. Also, it should be capable of active life style of moderner according to the change of the city environment. Furthermore, as a station is not just a single-purpose space anymore but the versatile space where fulfills the user's needs for the multi-function and the desire for diversity. As the station in these days opened 24 hours for users with the modern, commercial and cultural facilities, the interior design for a station needs to be designed to be easy to use, functional and able to vitalize the environment. In order to make a desirable interior environment in a station, first of all, it is required to grasp the characteristic of the space by analyzing the phenomena of an individual or a group act in a existing space formed by the interrelation between the human and the environment. To reduce the resistance against the new environment from the user, in other words, to increase the satisfaction, it is necessity to induce the behavior of the users to the desirable way toward to the new environment. Consequently, positive methodology with recognitive approach through cognitive psychology, spatial behavior research is required.