• Journal of the Korean Society of Physical Medicine
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• v.7 no.4
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• pp.433-442
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• 2012

PURPOSE: This study investigated to correlation between foot and knee posture characteristics in knee osteoarthritis patients. METHODS: The subjects of this study were 103 patients with clinically and radiographically-confirmed knee osteoarthritis was investigated using the quadriceps angle (QA), distance of both knee (DBK), ankle dorsiflexion angle (ADA), navicular drop (ND). One-way ANOVA and Pearson's correlation were used to investigate the correlation between foot and knee posture measurements. All of whom agreed to participate in the study. In order to assure the statistical significance of the results, we used for SPSS ver. 18.0 for windows. RESULTS: The results of this study were as follows : 1) There were statistically significant difference in the correlation between QA and DBK. 2) There were statistically significant difference in the correlation between DBK and ADA. CONCLUSION: According the results of this study, patients with osteoarthritis exhibit more genu varus knee posture. Moreover patients with osteoarthritis were not correlation between foot and knee Posture characteristics.

• Journal of Korean Physical Therapy Science
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• v.30 no.1
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• pp.23-30
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• 2023

Background: While agility is a critical factor in the performance of sport in the court field, due to the diversity of agility occurrences, it is generally difficult to develop by strength and conditioning training. Previous study reported the correlation with the static balance and agility. However, the correlation between dynamic balance and agility is insufficient. It is necessary to study how static and dynamic balance affect agility respectively, for agility development. Design: Cross sectional correlational study design Methods: Twenty young women participated in the study. Three tests were used : one leg stance(static balance),Y-balance(dynamic balance), side-step(agility). One leg stance measured time, Y-balance measured distance, and side-step measured number of times. Correlation between balance and agility was used by Pearson Correlation. Results: One leg stance and side steps were shown to be not correlated. The Y balance and the side step showed with a moderate positive correlation. Conclusion: Agility is a decisive factor in fast-moving sports performance, which is generally difficult to improve with muscle strength and conditioning training. Since the correlation between dynamic balance and agility was found in this study, the importance of dynamic balance was found to improve agility to promote coordination.

• Journal of Environmental Health Sciences
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• v.21 no.3
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• pp.107-114
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• 1995

To assess the contribution of automobile exhaust to indoor and outdoor levels of $NO_2$ around a major trunk road in Tokyo, $NO_2$ levels of 200 homes were measured at living rooms, kitchens and outdoor at each season, from the summer of 1990 to the spring of 1991, $NO_2$ level was measured for four days using diffusion $NO_2$ dosimeter. Outdoor $NO_2$ levels at each season and indoor $NO_2$ levels at seasons when heaters were not used decreased according to the distance from the roadside. The differences between $NO_2$ levels at zone I(within 20m from the roadside) and zone III(beyond 50m) was about 3 ppb. Automobile exhaust seemed to contribute to this difference. At seasons when heaters were used, indoor $NO_2$ levels of the homes equipped with vented heater, decreased according to the distance from the roadside. However, there was no correlation between indoor levels and the distance from the roadside at homes equipped with unvented heater.

• Journal of the Ergonomics Society of Korea
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• v.10 no.2
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• pp.51-55
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• 1991

Since slipping has been identified as a major hazard, it is important to understand the mechanism of a slip. Many researches, based on biomechanical studies, had been attempted to do that. Thowever, the correlation between the mechanism of a slip and psychophysical behaviors of people had rarely been verified. For example, the existence of small slips in a forward direction, which do not normally perceived by human subjects, has been established by several experimenters. However, the term "microslips are not perceived by the walkers[4]." has not been examined precisely by any experiments. The objective of this study is, using a Signal Detection Theory (SDT), to define a microslip and slip more quqntitatively with the biomechanical measurement of slip distance. The results showed that, the slip distance around the 3 centimeters, there was a obvious change in the accident detectability of the subject. The conclusion is that it is possible to identify the boundary of a microslip and slip around the 3 centermeters of slip distance.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1521-1524
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• 2003

In this paper, we propose a "Distance Correlation Selection operator (DCS)" as a new selection operator. For Genetic Algorithm (GA), many improvements have been proposed. The MGG (Minimal Generation Gap) model proposed by Satoh et.al. shows good performance. The MGG model has all advantages of conventional models and the ability of avoiding the premature convergence and suppressing the evolutionary stagnation. The proposed method is an extension of selection operator in the original MGG model. Generally, GA has two types of selection operators, one is "selection for reproduction", and the other is "selection for survival"; the former is for crossover and the latter is the individuals which survive to the next generation. The proposed method is an extension of the former. The proposed method utilizes distance information between individuals. From this extension, the proposed method aims to expand a search area and improve ability to search solution. The performance of the proposed method is examined with several standard test functions. The experimental results show good performance better than the original MGG model.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.12
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• pp.1203-1210
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• 1991

This paper proposes a new distance relaying method based on fault initiated travelling waves for transmission line protection. The characteristics of this method are ultra high speed and excellent sensitivity. Travelling wave technique which is one of the distance relaying methods uses the discrete cross correlation function for discrimination between internal and external fault is remarkably reduced in case of a close up fault and an inception angle near or equal to zero fault. To cope with this problem, a new fast algorithm which uses backward wave summation method with fixed window is presented. The proposed method has been tested by numerical simulations using the EMTP.

• Bulletin of the Korean Chemical Society
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• v.3 no.2
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• pp.44-49
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• 1982

Dynamic and equilibrium structures of a polymer chain immersed in solvent molecules have been investigated by a molecular dynamic method. The calculation employs the Lennard-Jones potential function to represent the interactions between two solvent molecules (SS) and between a constituent particle (monomer unit) of the polymer chain and a solvent molecule (CS) as well as between two non-nearest neighbor constituent particles of the polymer chain (CC), while the chemical bond for nearest neighbor constituent particles was chosen to follow a harmonic oscillator potential law. The correlation function for the SS, CS and CC pairs, the end-to-end distance square and the radius of gyration square were calculated by varying the chain length (= 5, 10, 15, 20). The computed end-to-end distance square and the radius of gyration square were found to be in a fairly good agreement with the corresponding results from the random-flight model. Unlike earlier works, the present simulation rsesult shows that the autocorrelation function of radius of gyration square decays slower than that of the end-to-end distance square.

• ETRI Journal
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• v.43 no.4
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• pp.746-757
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• 2021

Side-channel attacks pose an inevitable challenge to the implementation of cryptographic algorithms, and it is important to mitigate them. This work identifies a novel data encoding technique based on 1-of-4 codes to resist differential power analysis attacks, which is the most investigated category of side-channel attacks. The four code words of the 1-of-4 codes, namely (0001, 0010, 1000, and 0100), are split into two sets: set-0 and set-1. Using a select signal, the data processed in hardware is switched between the two encoding sets alternately such that the Hamming weight and Hamming distance are equalized. As a case study, the proposed technique is validated for the NIST standard AES-128 cipher. The proposed technique resists differential power analysis performed using statistical methods, namely correlation, mutual information, difference of means, and Welch's t-test based on the Hamming weight and distance models. The experimental results show that the proposed countermeasure has an area overhead of 2.3× with no performance degradation comparatively.

• Communications for Statistical Applications and Methods
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• v.30 no.2
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• pp.179-189
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• 2023

Hybrid sufficient dimension reduction (SDR) methods to a weighted mean of kernel matrices of two different SDR methods by Ye and Weiss (2003) require heavy computation and time consumption due to bootstrapping. To avoid this, Park et al. (2022) recently develop the so-called cross-distance selection (CDS) algorithm. In this paper, two variations of the original CDS algorithm are proposed depending on how well and equally the covk-SAVE is treated in the selection procedure. In one variation, which is called the larger CDS algorithm, the covk-SAVE is equally and fairly utilized with the other two candiates of SIR-SAVE and covk-DR. But, for the final selection, a random selection should be necessary. On the other hand, SIR-SAVE and covk-DR are utilized with completely ruling covk-SAVE out, which is called the smaller CDS algorithm. Numerical studies confirm that the original CDS algorithm is better than or compete quite well to the two proposed variations. A real data example is presented to compare and interpret the decisions by the three CDS algorithms in practice.

• Journal of Korean Society of Forest Science
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• v.84 no.4
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• pp.409-414
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• 1995

This study was carried out for the analysis and comparison about the noise diminution effects by the height, width and density of Euonymus japonica wall, the distance of sound source, the distance of sound receiver, the height of sound source, and the height of sound receiver. The results obtained were summarized as follows; 1. After the establishment of tree wall, the volume of noise diminution measured 6.8dB and the effects of noise diminution measured heigher than before by 10.6% and t-value was significant at the 1% level 2. In simple correlation between the effects of noise diminution and variables, the density of tree wall was found as the most significant factor, and the last were found in the order of the distance of sound receiver, the width of tree wall, and the distance of sound source. 3. In partial correlation coefficients the effects of noise diminution and variables, the density of tree wall (r=-0.959) was found as the most significant factor, and the last were found in order of the distance of sound receiver (r=-0.906) and the width of tree wall (r=-0.753). 4. The estimated equation to measure the effects of noise diminution according to variables (the height of tree wall, the width of tree wall, the density of tree wall, the distance of sound source, the distance of sound receiver, the height of sound source, and the height of sound receiver) was $Y=69.520-1.672X_1-1.656X_2-0.066X_3-0.248X_4-3.134X_5-0.222X_6-0.343X_7$, and the coefficient of determination of this estimated equation was highly found as 0.950. 5. In semi-partial correlation coefficient the effects of noise diminution were found in the order of the density of tree wall, the distance of sound receiver, the width of tree wall, and the height of tree wall from the highest to the lowest. Therefore, it was considered that the density of tree wall, the distance of sound receiver, the width of tree wall and the distance of sound source should be controlled effectively to increase the effects of noise diminution by Euonymus japonica wall.