• Journal of Veterinary Clinics
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• v.22 no.2
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• pp.100-107
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• 2005

This study was carried out to investigate the physical and chemical properties of teat cup liners. The hardness of the liners was $50\~67$, and their fatigue to failure 38-1,185 cycles. The elongation and tensile strength of these liners were about $134 kgf/cm^2\;and\;473\%$, respectively. The infrared spectrum and the gas chromatogram revealed that the liner A was consisted of NR, SBR, and BR, with a composition ratio of 60:20:20 (part per hundred rubber). The raw rubber materials used for liners B to G, on the other hand, were NBR only. However, the liner H was made of silicon rubber. The thermogravimetric analysis showed that the liners tested in this study contained raw rubber material, carbon black, organic compounds and metallic compounds.

• Journal of Technologic Dentistry
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• v.11 no.1
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• pp.47-63
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• 1989

The study was made to clarify the degree of fatigue of dental technicians in service at the general &local hospital or the dental laboratories in the large cith of korea. The objectives of this study were 235 dental technicians who replied the questionaire which was sent by postal service out of 600 dental technicians selected by random sampling among the workers of the each dental laboratory. The instruments used in this study was the same one as developed by Industry Fatigue committee of Japan Industry Hygiene Association. This instrument was included total 30 items which is consisted of 10 perceived symptoms of fatigue in physical, mental and neuro-sensory dimension respectably. Reliability was tasted with the data of objectives, in which value of Cronbach's $\alpha$ was 9457. The following results were obtained. 1. It was revealed that the influencing demographic variables on the perceived symptoms of fatigue of dental technicians were sex, age, marital status, educational background, job carrier, working part, working hour and commuting hour. The shorted the age or job carrier, thge higher dearee of the perceived symptoms of fatigue. The longer working hours of commuting hours, the higher degree of the perceived symptoms of fatigue. The degree of the perceived symptoms of fatigue in females, unmarried person, the one with higher educational background, workers except orthodontic appliances and poorcelain contouring were higher than the other group. 2. The higher degree of the rest & leisure condition, the lower degree of the physical, mental and neuro-sensory perceived symptoms. 3. The higher degree of environmental condition of the working, the lower degree of the physical, mental and neurosensory perceived symptoms.

• Journal of Korean Physical Therapy Science
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• v.16 no.4
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• pp.29-37
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• 2009

Background: The purpose of this study was influence of change of electrical stimulation time on body regions affects on electrical current threshold. Methods: The present study is to examine the effect of silver spike point (SSP) electrical stimulation (1Hz), transcutaneous electrical nerve stimulation (TENS, 100Hz), and interferential current therapy (ICT, 50Hz) from the low back and scapulodorsal and knee joint regions on stimulation-induced current thresholds from the elderly (over sixty) people (male:72, female:91) in senior welfare center. Result: The low back region, but not scapulodorsal and knee joint region, significantly increased the TENS and ICT, but not SSP, electrical stimulation, significantly increased the time-dependent current thresholds in elderly patients. Conclusion: Therefore, these results, in part, suggest that the TENS and ICT were shown to be a more adaptable method of stimulation, and that needed of the development of senile specialized physical therapy and the utilization of senior leisure facilities such as senior welfare center the others.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.4
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• pp.143-153
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• 2013

The rural tourism in Korea is expanding in scope including experience tours and integrating with dining industry these days. The Rural Development Administration in Korea has been supporting the farm restaurant project across the nation as part of its efforts to utilize local or rural food recipes as tourism resource for seven years. Over the years, however, case studies are rarely done or reported regarding physical environment of farm restaurants. This study offers an opportunity for farm restaurateurs and policy makers related to recognize the importance of developing brand identity and inner culture contents for the rural community by presenting a case of integrated design marketing. In the study, definitions of the "authentic food" in Korea and other countries are compared before farm restaurants at home and abroad are investigated. It also addresses the foundation on the significance of physical environment and design to build a brand identity of authentic food. The case presented is naming, designing and developing logos and design applicable to various product packages for "Hwanggeum Bori Aechan", which is the barley (main crop in Gimje)- dish development project for Gimje, North Jeolla Province in 2012.

• Journal of Power Electronics
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• v.18 no.6
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• pp.1771-1779
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• 2018

Modern trams with a super capacitor have gained a lot of attention in recent years due to its reliability, convenience, energy conservation and environmental friendliness. Because of its special charging characteristic, the traditional charging structure and control strategy cannot satisfy its charging requirements. This paper presents a new charging topology for fast charging modern trams with a super capacitor and it designs a controller using continuous control set model predictive control (CCS-MPC). There are three contributions in this paper. First, a new charging structure is designed and its mathematics model is derived. The cascade structure is adopted instead of the parallel structure to simplify the control process and to keep the rated power of the controllable part low. Second, a MPC control strategy is proposed to satisfy the charging characteristic. The optimal control signal can be obtained by solving the designed optimization problem. The optimal control signal is related to the discrete control action. In addition, mapping between the continuous control signal and the discrete control action is designed. Third, a semi-physical experimental platform is built to verify the proposed topology and control method. The simulation model and experiment platform are built to verify the correctness of the new structure and its control method. The results obtained show that the new topology can work effectively.

• PNF and Movement
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• v.3 no.1
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• pp.35-45
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• 2005

Objectives : The purpose of this study was to understanding the constraint induced movement and Self-efficacy with arm training on upper motor function in Stroke Patients. Methods : Stroke, the leading cause of functional disability, causes a variety of impairments that compromise quality of life. Upper limb hemiparesis, a commonly seen impairment, is particularly problematic given its impact on activities of daily living. Because stroke was a disease to correspond to the first during domestic cause of death, and was accompanied by a lot of side aftereffects after a survival, stroke rehabilitation bought a patient and a family and a physical therapist, and it was main concern of. Results : Looks into upper extremity excrise of a subacute stroke patient estranged a acute convalescence later by a rehabilitation treatment in this consideration, and evaluates an effect to wind up constraint induced movement for an early treatment of stroke and Self efficacy, and help is one to an early rehabilitation of an stroke patient. Conclusions : Overuse sound tends after the stroke occurrence in the early stage in order to recompense for stroke, and at the time of a new aspect called learned nonuse syndrome by a movement of a paralysis part dusting off wealth with this step thing later. Constraint induced movement using self efficacy could be an effective for improving function of stroke.

• Journal of Korean Public Health Nursing
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• v.32 no.3
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• pp.411-423
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• 2018

Purpose: This study was to form a healthy smartphone culture and serve as basic materials for developing smartphone addiction intervention program by understanding mental health and physical health of college students caused by smartphone addiction. Methods: The data collected from 261 college students at G and S city universities who understood the purpose of this study and consented to take part in the study were analyzed on mean, standard deviation, frequency, Chi square test and t-test using SPSS 20.0. Results: The result showed that the level of smartphone addiction was significantly different according to gender, age, type of college, satisfaction with college life and satisfaction with family life. The smartphone addiction risk group showed higher score in life stress, depression, social avoidance and distress than the general user group and the physical health was also higher in the risk group than the general user group. Conclusion: It is necessary to develop and apply customized intervention plan per each person's characteristics and level of addiction to prevent addiction and improve health condition from overuse of smartphone.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.6
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• pp.2094-2114
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• 2022

Due to the wide application of fifth generation communication, wireless sensor networks have become an indispensable part in our daily life. In this paper, we analyze physical layer security for two-way relay with energy harvesting (EH), where power splitter is considered at relay. And two kinds of combined methods, i.e., selection combining (SC) and maximum ratio combining (MRC) schemes, are employed at eavesdropper. What's more, the closed-form expressions for security performance are derived. For comparison purposes, this security behaviors for orthogonal multiple access (OMA) networks are also investigated. To gain deeper insights, the end-to-end throughput and approximate derivations of secrecy outage probability (SOP) under the high signal-to-noise ratio (SNR) regime are studied. Practical Monte-Carlo simulative results verify the numerical analysis and indicate that: i) The secure performance of SC scheme is superior to MRC scheme because of being applied on eavesdropper; ii) The secure behaviors can be affected by various parameters like power allocation coefficients, transmission rate, etc; iii) In the low and medium SNR region, the security and channel capacity are higher for cooperative non-orthogonal multiple access (NOMA) systems in contrast with OMA systems; iv) The systematic throughput can be improved by changing the energy conversion efficiency and power splitting factor. The purpose of this study is to provide theoretical direction and design of secure communication.

• Journal of Korean Port Research
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• v.6 no.1
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• pp.49-68
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• 1992

Recently changes in the technological environment of marine transportation and the increase of traffic volume have fostered a revolution in the design and operation of port and also playing a major role in the development of new types of port in Asian. These changes are dynamic and will continue to influence port physical distribution system. The port of Pusan has been hardly able to handle the traffic increases in recent years by expansion increased mechanization and other operational and institutional improvements but, further traffic increases bring about critical congestion and such congestion is an economic cost to the country in terms of cost of physical distribution. This paper treats the development of entirely new port of Pusan and related transportation system by considering the existing or expected need for improved port capacity and services. The western part of GADUK island is selected as the optimum port site through the detailed analysis of the physical requirement and careful consideration of regional development and since the lead time of the national development plan including the port project from initial planning to implementation is considered as long as 7 to 10 years the aggregated master plan for port development is made and implemented in the year of 2012.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.1
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• pp.16-24
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• 2022

A computational study of combined thermal and solutal convection (double diffusive convection) in a sealed crystal growth reactor is presented, based on a two-dimensional numerical analysis of the nonlinear and strongly coupled partial differential equations and their associated boundary conditions. The average Nusselt numbers for the source regions are greater than those at the crystal regions for 9.73 × 10³ ≤ Gr_t ≤ 6.22 × 10⁵. The average Nusselt numbers for the source regions varies linearly and increases directly with the thermal Grashof number form 9.73 × 10³ ≤ Gr_t ≤ 6.22 × 10⁵ for aspect ratio, Ar (transport length-to-width) = 1 and 2. Additionally, the average Nusselt numbers for the crystal regions at Ar = 1 are much greater than those at Ar = 2. Also, the occurrence of one unicellular flow structure is caused by both the thermal and solutal convection, which is inherent during the physical vapor transport of Hg₂Br₂. When the aspect ratio of the enclosure increases, the fluid movement is hindered and results in the decrease of thermal buoyancy force.