• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.1
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• pp.41-55
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• 2023

Urban parks create the natural landscape of the city and offer a space for city residents to stay healthy and take a rest. They are also urban facilities designed to improve city dwellers' emotional aspects. Currently, urban parks need qualitative management as well as quantitative supply due to changes in the national land and urban policy paradigm, and a shift in perspective to consumer-centeredness is needed. In this study, the service levels of urban parks for citizen were evaluated: (1) quantitative supply adequacy was analyzed based on the urban population, and (2) the qualitative evaluation of the parks were conducted. Based on the evaluation, the appropriateness of the arrangement of urban parks is judged by comprehensively analyzing the quantitative and qualitative aspects. As a result of the evaluation of service levels of urban parks, the highest serviced urban parks were found in urban housing development sites and recently established parks. In addition, it was found that the recently created parks improved the qualities of the parks by installing various facilities. If the quantitative and qualitative aspects of urban park service supply are comprehensively analyzed and applied through this research method, it will be a more effective park and green space plan.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4A
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• pp.475-485
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• 2008

This paper intends to enhance the reliability and performance of domestic elastomeric bearings through the proposal of directions for the improvement of their stiffness regard to the Korean industrial standard KS F 4420 relative to the evaluation of design/fabrication/quality. Therefore, comparative analysis of the compressive elastic modulus, stiffness measurement method and performance evaluation method of KS F 4420 with those of Eurocode, Japanese bearing manual, and ISO code was performed, and measurement tests on the compressive stiffness and shear stiffness of common elastomeric bearings produced in Korea were conducted. The experimental results reveal that differences of about 20% and 13% occurred respectively for the compressive stiffness and shear stiffness according to the definition adopted for the stiffness. The measured values for the stiffness of the domestic elastomeric bearings were also verified to exhibit large deviation from the formula proposed by KS F 4420. Elastomeric bearings that does not have appropriate compressive stiffness required at the design can result in uneven deflection at supports of bridges and excessive stress in girders. Accordingly, the establishment of compressive elastic modulus formula and performance evaluation criteria fitted to the domestic circumstances through the execution of performance evaluation of bearings presenting diversified shapes and shape factors appears to be necessary for the domestic bearings to meet the performance required in design.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.1
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• pp.261-269
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• 2014

There are many researches on fast exponentiation algorithm which is used to implement a public key cryptosystem such as RSA. On the other hand, the malicious attacker has tried various side-channel attacks to extract the secret key. In these attacks, an attacker uses the power consumption or electromagnetic radiation of cryptographic devices which is measured during computation of exponentiation algorithm. In this paper, we propose a novel simple power analysis attack on m-ary exponentiation implementation. The core idea of our attack on m-ary exponentiation with pre-computation process is that an attacker controls the input message to identify the power consumption patterns which are related with secret key. Furthermore, we implement the m-ary exponentiation on evaluation board and apply our simple power analysis attack to it. As a result, we verify that the secret key can be revealed in experimental environment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3733-3739
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• 2010

This paper suggests the measurement method of evaluation of management performance factors in health organization using AHP and Factor Analysis technique. To achieve this goal, this study applies AHP method to different size of hospitals. AHP method is deployed in three steps. At first step, the major factors, which indicate the management performance in health organizations, will be formed through factor analysis. At second step, the pairwise comparison between two factors will be performed to calculate the weights of each variables. At the last step, the order of priority of all factors will be determined. This order list will be used in measurement of the management performance in health organization. The results of this paper show that the financial factors take the top position, and followed by customer related factors, process factors and education & growth factors. This result could be the milestone for the measurement of management performance of medical organization in Korea.

• Journal of the Korean Geotechnical Society
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• v.18 no.2
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• pp.97-105
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• 2002

Random properties of discontinuities were attributed to the limitation of test methods and lack of obtained data. Therefore, the uncertainties are pervasive and inevitable in rock slope engineering as well as other geotechnical engineering fields. The probabilistic analysis has been proposed to deal properly with the uncertainty. However, previous probabilistic approaches do not take account of the condition of kinematic instability but consider only kinetic instability. In this study, in order to overcome the limitation of the previous studies, the geometric characteristics as well as the shear strength characteristics in discontinuities are taken account into the probabilistic analysis. Then, the new approach to evaluate the probability of failure is suggested. The results of the deterministic analysis which was carried out to compare with the result of the probabilistic analysis, are somewhat different from those of the probabilistic approach. This is because the selected and used data in the deterministic approach do not take account of the random properties of discontinuities.

• Journal of Korean Neurosurgical Society
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• v.66 no.4
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• pp.382-392
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• 2023

Objective : The use of indocyanine green videoangiography (ICG-VA) to assess blood flow in the brain during cerebrovascular surgery has been increasing. Clinical studies on ICG-VA have predominantly focused on qualitative analysis. However, quantitative analysis numerical modelling for time profiling enables a more accurate evaluation of blood flow kinetics. In this study, we established a multiple exponential modified Gaussian (multi-EMG) model for quantitative ICG-VA to understand accurately the status of cerebral hemodynamics. Methods : We obtained clinical data of cerebral blood flow acquired the quantitative analysis ICG-VA during cerebrovascular surgery. Varied asymmetric peak functions were compared to find the most matching function form with clinical data by using a nonlinear regression algorithm. To verify the result of the nonlinear regression, the mode function was applied to various types of data. Results : The proposed multi-EMG model is well fitted to the clinical data. Because the primary parameters-growth and decay rates, and peak center and heights-of the model are characteristics of model function, they provide accurate reference values for assessing cerebral hemodynamics in various conditions. In addition, the primary parameters can be estimated on the curves with partially missed data. The accuracy of the model estimation was verified by a repeated curve fitting method using manipulation of missing data. Conclusion : The multi-EMG model can possibly serve as a universal model for cerebral hemodynamics in a comparison with other asymmetric peak functions. According to the results, the model can be helpful for clinical research assessment of cerebrovascular hemodynamics in a clinical setting.

• International Commerce and Information Review
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• v.12 no.2
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• pp.59-83
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• 2010

The purposes of the study is to evaluate the discrepancy between user's expectation and satisfaction degree in the service of uTradeHub. In this regard, this study infers general solutions in order to induce the intersection area using IPA technique. Then this paper will present directions to improve the service of uTradeHub. In terms of methodology, this article disclosed that IPA model approach is greatly useful to evaluate user's attribute. First, variables like the link of different works(f1), trust of system(f4), information connection(f7) are located on the first quadrant. This means that importance and satisfaction are all high variables for user. So, this is very important variables that need continuous administration in order to maintain present state. Second, variables such as the speed of information acquisition(f2), improvement of use(f3), stability of system(f5) are located on the second quadrant. This means that user's importance is high but user's satisfaction is low. Therefore, this area needs an active improvement strategy and quick maintenance for e-Trade application. Third, variables like the appropriateness of information usage fees(f8), easy subscription(f9), customer support service(f10) are located on the third quadrant. Because these variables are all low for user's importance and satisfaction, we have to arrange strong and radical remedy for e-Trade service. Finally, variables like information offer(f6) are located on the fourth quadrant. This means that user's satisfaction is high but user's importance is low. The research result suggests that e-Trade service development would be re-organised as much as user feels the importance of process innovation.

• Journal of Korean Institute of Industrial Engineers
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• v.25 no.1
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• pp.56-66
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• 1999

Shoulder joint is the most movable joint in human body with, at least, three degrees of freedom, since there are at least three bones and five joints involved in shoulder movement. Due to the complexity of the shoulder joint and the lack of appropriate anatomical data, modeling of the shoulder joint has been known to be extremely difficult. In many biomechanical models being used, shoulder joint is considered as a fixed point and it is also assumed that the shoulder joint does not noticeably move during the shoulder movement. However, such an assumption is not valid in real applications and causes inaccuracy, especially, in the area of workspace evaluation. The reachable area generated by a human becomes somewhat different from that of current models for those models fail to appropriately reflect the movement of shoulder joint's center of rotation. In this study, the location of the shoulder joint's center of rotation was obtained in relation to the location of humerus, on which a new model for reach envelope generation was developed for workspace evaluation. From the experiments conducted for three subjects, the initial location of the center of rotation was determined for each subject and subsequent changes in the instantaneous center of rotation were drawn as a function of flexion and abduction of the shoulder. Based on the regression analysis, the study suggested a new method for the generation of reach envelope. Comparisons were also made among real reach envelopes obtained from the experiment, the ones from the model, and the ones from the new method suggested in the study. As a result, the prediction errors incurred from the new method were significantly reduced when compared to the ones from the current approach.

• Journal of Korean Society of Steel Construction
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• v.17 no.2 s.75
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• pp.151-159
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• 2005

This study investigated the capacity evaluation of composite beam of the end-reinforced concrete, the center steel with attached main-bar of stud-bolt welting and flange with main parameter, such as shear span depth ratio (a/d=1.5, 2.5, 3.5), reinforcing method, reinforcing length, and steel main-bar ratio. The test results are summarized as follows: As the RC section becomes longer, the capacity ratio of Vsrc, test/Vsrc, the gradually decreased, with the tendency of decrease being remarkably more than a/d=3.5. The reinforcing method showed superior result both vertically and horizontally. And, capacity increase ratio displayed tendency that main-bar fixing length is obvious in 0.15L, and underestimate experimental value usually in Vsrc, Eq(3)~(5) equation. The capacity estimation was proposed equation by regression analysis with change of shear span depth ratio and main-bar fixing, steel main-bar ratio.

• Journal of the Korean Society for Railway
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• v.14 no.3
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• pp.234-239
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• 2011

Installing the temporary bridge after excavating the railway requires installing movable cross beam, but as it doesn't requires isolating the catenary or cutting the rail, it's applicable to double-track with frequent operation. In this study, a displacement meter was placed on temporary bridge to monitor the displacement pattern in curve section (R400) completed using temporary bridge method, and wheel load, lateral pressure and derailment coefficient were measured to evaluate the load imposed on track and the stability in curve section (R400) for quantitative evaluation of training running safety. As a result of the measurement, when trains passing over a temporary bridge, the maximum value of Wheel load and Lateral Force is analyzed as the 51% and 81% of standard level according to foreign country's performance tests, There is no trouble with stability analysis in Wheel load and Lateral Force occurring. Additionally, Wheel load and Lateral Force considered as the safety standard are tested 49% of limiting value regardless of trains, which the norm value quite well, there is no problem with train running.