• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.6
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• pp.2255-2281
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• 2021

Channel characteristic-based physical layer authentication is one potential identity authentication scheme in wireless communication, such as used in a fog computing environment. While existing channel characteristic-based physical layer authentication schemes may be efficient when deployed in the conventional wireless network environment, they may be less efficient and practical for the industrial wireless communication environment due to the varying requirements. We observe that this is a topic that is understudied, and therefore in this paper, we review the constructions and performance of several commonly used test statistics and analyze their performance in typical industrial wireless networks using simulation experiments. The findings from the simulations show a number of limitations in existing channel characteristic-based physical layer authentication schemes. Therefore, we believe that it is a good idea to combine machine learning and multiple test statistics for identity authentication in future industrial wireless network deployment. Four machine learning methods prove that the scheme significantly improves the authentication accuracy and solves the challenge of choosing a threshold.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.8 no.1
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• pp.23-29
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• 2010

Purpose : This study is to offer clinical primary data that examines the change of imaging structure and the quantitative evaluation of muscle activity on myofascial trigger points. This study examines neuromuscular physiological characteristic by comparing the differences in physical findings, pressure pain threshold, imaging, and electrophysiological characteristics in latent and active myofascial trigger points muscle and normal muscle through the following experimental procedures. Methods : The participants for the study were thirty-three adults in their twenties. We divided three groups into normal, latent and active myofascial trigger points groups by physical findings. We analyzed the results of measured pressure pain, threshold for pain, ultrasound imaging perform for structure characteristic of muscle, surface EMG according to type of muscle contraction for function of muscle contraction. Results : Significant differences were indicated in pressure pain threshold (p<0.05). Significant differences were discovered in the ultrasound imaging analysis. There were increases in muscle Echogenicity white area index (p<0.001). There were significant differences that decrease in %MVIC (p<0.05), increase in MDF (p<0.05). Conclusion : From these results, active rnyotascial trigger points muscle showed quality deterioration on ultrasound imaging and decreased function of muscle contraction, increased motor unit action potential of II type fiber, and electrophysiologically. Imaging structure and neuromuscular physiological characteristic can be diagnostic and quantitative analytical techniques for myofascial pain syndrome and a primary factor that reflected in physical therapy intervention.

• Korean Journal of Human Ecology
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• v.2 no.2
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• pp.17-28
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• 1999

The purpose of this study was to investigate the effects of children's individual characteristic on peer acceptance. The subjects were 234 6th grade elementary school children in Kwangju, Korea. The Questionnaires were used to collect the data on peer acceptance and social behavioral trait, physical attractiveness, demographic variables and the school achievement grade assessed by their teachers. The results were as follows : 1. Peer acceptance score, school achievement grade, prosocial behavior score, appearance score and physical attractiveness tend to be above the median scores. Aggression behavior score and withdrawal score tend to below the median scores. 2. The effect of individual characteristic variables on the peer acceptance found all significantly. 3. The influence of prosocial behavior, physical attractiveness, withdrawal behavior, aggressive behavior and school achievement grade on peer acceptance were found significantly. Prosocial behavior was the most influential variable on peer acceptance.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.1
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• pp.156-163
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• 2006

While sludge is settling in batch column, sludge concentration becomes high. Because the characteristic of sludge settling changes in function of time due to the sludge concentration change, the sludge settling velocity changes too. Also, because the sludge settling characteristic is influenced by a physical characteristic of sludge and a column height etc, it is difficult to exactly measure the sludge settling characteristic. Although the sludge volume indexes, SVI, SSVI and $SSVI_{3.5}$, are used to predict sludge settling characteristic, these indexes are not reliable values. Because the previously established models for sludge settling velocity predict the sludge settling velocity only, it is difficult to predict sluge-water interface height by using those models. The purpose of this experiment is to establish the empirical model which predicts the sludge interface height change with respect to the sludge physical characteristic and the settling condition.

• Proceedings of the Korea Concrete Institute Conference
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• 1991.10a
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• pp.1-4
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• 1991

Relationship between againg and characteristic change of asphalt is not well known through asphalt rheolopy. Therefore, this study was conducted to evaluate characteristic change of asphalt cement due to againg based on experimental results of chromatogram and selected physical properties. Currently, three virgin asphalt cements were tested for physical properties and chromatograms before and after artificially conditioning for againg. Results in the current study showed that againg caused significant changes of physical properties and increase of larger size molecules and approximately corresponding reduction of smaller size molecule in asphalt cement molecular size distribution.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.42 no.3 s.303
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• pp.41-46
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• 2005

In this paper, we proposed noninvasive and continous measurement of blood pressure using pulse transit time(PTT) and physical characteristic parameters and verified its clinical effectiveness. PTT can be obtained by electrocardiogram and phtoplethysmogram. There are many researches for estimating blood pressure using PTT which can be used for individual. However, it is not enough for extracting general regression equation which can estimate blood pressure for unspecified people. In this study, we suggested the regression equatin using PTT and physical characteristic parameters related to blood pressure and did measure blood pressure of many people. we compared the performance between two methods. As the results, we knew that the regressin model using PTT combined with physical characteristic parameters can estimate blood pressure more acurately and is closer to American National Standards Institute of the Association of the Advancement of Medical Instrument(ANSI/AAMI).

• Structural Engineering and Mechanics
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• v.28 no.2
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• pp.167-188
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• 2008

This study is concerned with the establishment of the characteristic equation of a combined system consisting of a cantilever beam with a tip mass and an in-span visco-elastic helical spring-mass, considering the mass of the helical spring. After obtaining the "exact" characteristic equation of the combined system, by making use of a boundary value problem formulation, the characteristic equation is established via a transfer matrix method, as well. Further, the characteristic equation of a reduced system is obtained as a special case. Then, the characteristic equations are numerically solved for various combinations of the physical parameters. Further, comparison of the results with the massless spring case and the case in which the spring mass is partially considered, reveals the fact that neglecting or considering the mass of the spring partially can cause considerable errors for some combinations of the physical parameters of the system.

• The Journal of Korean Physical Therapy
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• v.14 no.3
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• pp.407-417
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• 2002

The purpose of this study was to examine the influence of general characteristic of the patient with low back pain on the psychologic Status. The Questionnaires was done for 312 persons with low back pain who live in Daejeon. The study was conducted between 1st, June and 26th, July in 2000. The results were as follows: 1. The effects of general characteristic of the patient with low back pain on the psychologic Status were related age(p<0.01), education level(p<0.01), job(p<0.01), husband and wife existence(p<0.01), disease(p<0.01). 2. The influence of an item on Handler score was related the reason of pain(r=0.377, p<0.01), the site and pattern of pain(r=0.314, p<0.01), the influence of climate(r=0.370, p<0.01), the frequency of pain(r=0.396, p<0.01), the position of producible pain(r=0.411, p<0.01), one's desire(r=0.394, p<0.01), experience of pessimism(r=0.421, p<0.01).

• Journal of Korean Academy of Fundamentals of Nursing
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• v.2 no.2
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• pp.183-197
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• 1995

This study was performed to investigate the characteristic of physical touch in caring situation. The subjects of this study were adults in caring situation, therefore they were composed of 7 patients, 6 nurses, 3 doctors, 3 pharmacologists, 3 men in paramedicine area, 3 nursing educators and 13 normal general adults. The datas were gathered through nonstructured questionaire from June, 20th to September, 15th in 1995. The datas were subjects' descriptions about the intention, perception, and form of physical touch in caring situation and analysed by content analysis. The results as follow : The datas were divided into four areas. There were the situation being necessiated the physical touch, meaning of physical touch, form of physical touch and perception about physical touch in caring situation. The situation being necessiated physical touch were the situation that required physical treatment, to deliver the active expression of concern about the patients, to determine the treatment due to the identification of physical condition of patients and to induce the psychological eqilibrium into patient's mind. The meanings of physical touch in caring situation were - Good meanings that intention is to encourage, to be have hope about health and to deliver the affection willing to help patient. - therapeutic methods that were to facillitate the circulation of blood, to reduce the pain perception and to facillitate the circulation of qi. - interpersonal affectionate relation that the intentions were to deliver the understanding of patient's pain, were to delivery the meaning to the patient not be alone. The forms of physical touch in caring situation were none invasive forms just like laying hands on hand, head, shoulder, gentle knocking on the shoulder or back, massage of legs and back and finger pressure on acupuncture points. The perception of physical touch in caring situation divided into two parts. In family, the perceptions of physical touch in caring situation were to promote health status because physical touch induce the psychological peace, and to evoke the importance of relationship among family members. In relation with care giver, perception of physical touch in caring situation were inevitable process in treatment, and to deliver the trust and concern about patients.

• Journal of the Korean Physical Society
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• v.73 no.9
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• pp.1405-1405
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• 2018