• ETRI Journal
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• v.29 no.1
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• pp.113-115
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• 2007

A dynamic tri-threshold call admission control scheme has been developed. This scheme supports voice, data, and multimedia services and it complies with the universal mobile telecommunications system. The performance of the proposed scheme is evaluated under varying handover rates. The QoS performance-including channel utilization, call dropping probability, and blocking probability-is investigated. The performance of the developed scheme is found to be encouraging.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.8
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• pp.1-9
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• 1997

Soft handoff provided in CDMA cellular system has much advantage such as better service quality, interference control and low call dropping probability. In this paepr, we propose an optimum resource reservationscheme for handoff calls in the CDMA cellular system to increase the soft handoff probability in handoff. In the proposed scheme, resources of each frquency channel are reserved for handoff according to the number of its neighbot cells serving the same frequency channel. A performance analysis shows that the soft handoff probability of the proposed scheme is higher than that of conventional scheme disregarding the condition of frquency assignment of neighbot cells, and that ever frequency channel served by neighbor cells should reserve more than one traffic channel for handoff to get good performance.

• Journal of the Korean Chemical Society
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• v.9 no.2
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• pp.71-74
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• 1965

Reduction of Ti(Ⅳ)-oxalate complex on dropping mercury electrode has been studied as a function of oxalate concentration and of pH varied with HCl. Assuming there are equilibrium $TiO(C_2O_4)_2= \;+\;2H^+\;=\;Ti^{+4}\;+\;2C_2O_4\;=\;+\;H_2O,\;K_4$ in addition to $TiO(C_2O_4)_2\;^=\;=\;TiO^{++}\;+\;2C_2O_4=\;K_2\;Ti(C_2O_4)_2\;^-\;=\;Ti^{+3}\;+\;2C_2O_4=\;K_3$ in the system cathodic wave has been well explained for that pH is higher than 0.5. The equilibrium constants $K_2,\;K_3$ and $K_4$ have been to be $2{\times}10^{-12},\;5{\times}10^{-13}$ and $10^{-11}$, respectively. The reduction of Ti(Ⅳ)-oxalate system is $Ti^{+4}\;+\;e\;{\to}\;Ti^{+3}$ in the concentration of hydrochloric acid, higher than 3M.

• Journal of the Korea Safety Management & Science
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• v.8 no.4
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• pp.13-23
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• 2006

Grip strength provides a quick and objective index of the functional integrity of the upper extremities. It is widely used as an assessment measure in physical and rehabilitation medicine. In this study, maximum voluntary grip strength of 20 college students wearing 5 different gloves were measured using Jamar hand dynamometer. The results show that maximum voluntary grip strength was generally reduced when wearing gloves as compared to bare-handed. More specifically, the grip strength was highest when wearing PVC coated glove or bare-handed and getting lowered as wrist band, rubber, leather, and cotton glove in these order. Depending on the measuring posture of grip strength, shoulder height with arm extended forward was higher than the elbow was flexed 90 degree. Moreover, subjects' demographic factors and hand dimensions were not closely related to the grip strength. It is thus recommended that the proper glove should be provided to reduce the negative consequences including dropping a tool, poorer control of a tool. lower quality work, and increased muscle fatigue and in turn to increase the user safety and satisfaction.

• Journal of Korean Institute of Industrial Engineers
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• v.19 no.4
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• pp.3-11
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• 1993

We propose a new dual simplex method using a primal interior point. The dropping variable is chosen by utilizing the primal feasible interior point. For a given dual feasible basis, its corresponding primal infeasible basic vector and the interior point are used for obtaining a decreasing primal feasible point The computation time of moving on interior point in our method takes much less than that od Karmarker-type interior methods. Since any polynomial time interior methods can be applied to our method we conjectured that a slight modification of our method can give a polynomial time complexity.

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.125-130
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• 2004

It is not difficult to see the road repairing. There are many and various machines that can crush road surface. The efficiency and power of the machine depend on crushing head-shape, crushing interval, crushing load, crushing stress, machine's dropping height and roller's kind. The objective of this study is to select the optimal model among ten models of crushing machine with constraints such as crushing depth, variation, and crushed particle size. The data for this study are chosen from the site of construction in Kangnung during three months ($2004.\;6.\;1\;\sim\;2004.\;8.\;31$). The provided methodology in this paper will be fruitful not only for the selection of crushing machine but also for the aspects of construction period, cost, work efficacy according to the condition from the various sites of construction.

• Plant Journal
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• v.6 no.4
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• pp.56-62
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• 2010

This study investigated characteristics of the post-weld heat treatment of SA213-T23, which was developed for water wall of the ultra super critical power boiler. The temperature of post weld heat treatment should be $730^{\circ}C$ or higher to reduce hardness of the deposit metal and heat affected zone. Coincidently, the temperature should remain $760^{\circ}C$ or lower to prevent hardness of the base metal from dropping. Hardness decline of deposit metal was trivial according to time when the holding time of heat treatment at $740^{\circ}C$ of post-weld heat treatment gradually increased from initial 15 minutes.

• Korean Journal of Child Studies
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• v.23 no.4
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• pp.119-136
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• 2002

This study examined teacher's perceptions of the psychosocial adjustment and problem behaviors of institutionalized children compared with home reared children. Data were collected from the teachers of institutionalized children in elementary and secondary schools. The majority of institutionalized children were regarded as not very much different from home reared children. Still, findings from this study lead to conclusions that institutionalization is likely to elevate children's risk for adjustment problems such as social withdrawal, peer violence, and academic failure. Findings that the ratio of institutionalized children attending school decreased with age lead to speculation that failure in psychosocial adjustment may lead to to dropping out of school. Finally, a practical framework for the optimal development of institutionalized children is provided, with emphasis on school-community based interventions.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.1 s.32
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• pp.195-200
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• 2007

Objective : This experimental study was performed to investigate the effect of Jinpi-san on Staphylococcus aureus(S. aureus) and Staphylococcus epidermidis(S. epidermidis) that induce keratitis. Methods : Minimal inhibitory concentration(MIC) was measured by dropping to $50{\mu}l$ according to density Jinpi-san(100%, 10%, 1%, 0.1 %). Anti-bacterial potency was measured by the size of inhibition zone with change of volume. Results : 1. MIC on S. aureus in Jinpi-san was $40{\mu}l$ undiluted solution. 2. MIC on S. epidermidis in Jinpi-san was $20{\mu}l$ undiluted solution. Conclusions : These results indicate that Jinpi-san can be used to cure S. aureus, S. epidermidis that induce eye disease(keratitis). If further study is performed, the use of eye drops will be valuable and beneficial in the clinical medicines.

• Korean Journal of Logic
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• v.14 no.1
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• pp.55-76
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• 2011

Fixed-point conjunctive left-continuous idempotent uninorms have been introduced (see e.g. [2, 3]). This paper studies a system for such uninorms. More exactly, one system obtainable from IUML (Involutive uninorm mingle logic) by dropping involution (INV), called here WUML (Weak Uninorm Mingle Logic), is first introduced. This is the system of fixed-point conjunctive left-continuous idempotent uninorms and their residua with weak negation. Algebraic structures corresponding to the system, i.e., WUML-algebras, are then defined, and algebraic completeness is provided for the system. Standard completeness is further established for WUML and IUML in an analogy to that of WNM (Weak nilpotent minimum logic) and NM (Nilpotent minimum logic) in [4].