• Journal of Internet Computing and Services
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• v.6 no.3
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• pp.107-119
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• 2005

The Mobile IP has evolved from providing mobility support for portable computers to support wireless handheld devices with high mobility patterns. The Mobile IP secures mobility, but does not guarantee security, In this paper, the Mobile IP has been adapted to allow AM protocol that supports authentication, authorization and accounting for authentication and collection of accounting information of network usage by mobile nodes, For this goal, we propose a new security handoff mechanism to intensify the Mobile IP security and to achieve fast handoff. In the proposed mechanism, we provide enough handoff achievement time to maintain the security of mobile nodes, According to the analysis of modeling result, the proposed mechanism composed the basic Mobile IP along with AM protocol is up to about $60\%$ better in terms of normalized surcharge for the handoff failure rate that considers handoff time.

• Journal of Labour Economics
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• v.40 no.2
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• pp.31-68
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• 2017

This study examined the moonlighting behavior in Korea, to which relatively less attention has been paid. Based on the wage earners of 25 to 65 year old married, the results show that about 1.4% of the sample have dual jobs, working very long hours, on average 60 hours for a week combining both the primary job and the secondary job. The results of the fixed effects logit model on the moonlighting participation indicate that the wage rate and the hours of work in the primary job have a negative effect on moonlighting participation while the insecurity of the primary job appears to lead to a higher probability of taking a secondary job. The results of the moonlighting hours analysis suggest that hours worked in the primary job have a negative effect on moonlight hours while the wage of the primary job does not appear to have any significant effect on moonlighting hours. Interestingly enough, the wage of the secondary job appears to have a negative impact on moonlighting hours, which might be very plausible considering the long working hours moonlighters are engaged in.

• Journal of the Korean Institute of Gas
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• v.21 no.5
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• pp.9-15
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• 2017

Natural gas fuel has known to be very promising in terms of abundancy and economic value. Therefore it is widely treated as research topics in a variety field of production, storage and utilization. Natural gas has become one of the major sources for the power generation by using internal combustion engines(ICE). Development of natural gas fuel injection device should be preceded to realize a reliable natural gas fuel supply system for a MW class power generation reciprocating ICE. In this research, an injection valve which consists of solenoid and body part with a moving plate was designed and its dynamic performance was experimented in the engine-like environment. Displacement length and diameter of an armature and diameter of a solenoid coil were tested at former study. In this research the effect of materials of solenoid core, size of main housing inlet and supply gas pressure are examined.

• The Plant Pathology Journal
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• v.33 no.6
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• pp.608-613
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• 2017

The full-length sequence of a new isolate of Apple chlorotic leaf spot virus (ACLSV) from Korea was divergent, but most closely related to the Japanese isolate A4, at 84% nucleotide identity. The full-length cDNA of the Korean isolate of ACLSV was cloned into a binary vector downstream of the bacteriophage T7 RNA promoter and the Cauliflower mosaic virus 35S promoter. Chenopodium quinoa was successfully infected using in vitro transcripts synthesized using the T7 promoter, detected at 20 days post inoculation (dpi), but did not produce obvious symptoms. Nicotiana occidentalis and C. quinoa were inoculated through agroinfiltration. At 32 dpi the infection rate was evaluated; no C. quinoa plants were infected by agroinfiltration, but infection of N. occidentalis was obtained.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.6
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• pp.81-91
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• 2013

A novel design process of a parallel multi-flow type air-cooled condenser of a dual-loop waste heat recovery system with Rankine steam cycles for improving the fuel efficiency of gasoline automobiles has been investigated focusing on reduction of the pressure drop inside the micro-tubes. The low temperature condenser plays a role to dissipate heat from the system by condensing the low temperature loop working fluid sufficiently. However, the refrigerant has low evaporation temperature enough to recover the waste from engine coolant of about $100^{\circ}C$ but has small saturation enthalpy so that excessive mass flow rate of the LT working fluid, e.g., over 150 g/s, causes enormously large pressure drop of the working fluid to maintain the heat dissipation performance of more than 20 kW. This paper has dealt with the scheme to design the low temperature condenser that has reduced pressure drop while ensuring the required thermal performance. The number of pass, the arrangement of the tubes of each pass, and the positions of the inlet and outlet ports on the header are most critical parameters affecting the flow uniformity through all the tubes of the condenser. For the purpose of the performance predictions and the parametric study for the LT condenser, we have developed a 1-dimensional user-friendly performance prediction program that calculates feasibly the phase change of the working fluid in the tubes. An example is presented through the proposed design process and compared with an experiment.

• The Korean Journal of Pharmacology
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• v.15 no.1_2 s.25
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• pp.45-56
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• 1979

With a view to searching after a new antihypertensive or hypotensive agents in the botanical crude plants, authors intended to reevaluate several natural products caltivated in Korea. This experiment was undertaken to compare pharmacogical actions of Machilus thunbergii Siebold et Zuccarini with those of Magnolia obovata Thunberg in anesthetized rats and in normal mice. Machilus thunbergii Sieb. et Zucc., a tree belonging to the Lauraceae family, is caltivated at Ull-ung Do, and their cortecies have been used as folk medicine mingled with those of Magnolia obovata Thunberg. These two cortecies have teen also applied in chinese medicine, it was advocated that these cortecies exerted good therapeutic effects on gastritis, convulsive abdominal pain, nausea, vomiting and urinary tract disorders. Therefore, we intended to determine the pharmacological action of two palnt of different family each other, especially their effects on blood pressure and heart rate, and also their mechanism of action were observed. We studied their action with extracts of hexane(MTHE), ether(MTEE), methanol(MTME) and water(MTWE) from Machilus thunhergii Sieb. et Zucc., and also fractionations of methanol(MOME), chloroform(MOCE) and water(MOWE) from Mapolia obovata Thunberg. The results of this experiment were as follows; 1) MTME, when intravenously administered to rats, elicited the significant hypotensive responses dependent on the administered dosage. 2) MOWE was also exhibited the hypotensive effect dependent on the treated dose. 3) Depressor effect of MTME was blocked by pretreatment with hexamethonium. 4) The hypotensive response of MOWE was blocked by pretreatment with hexamethonium or hrdralazine. 5) HTME and MOWE were also observed the anticonvulsive effect and sedative effect. These results suggested that MTME may induce the hypotensive response via central sympathetic effect, but the site of action in brain are not clarified, and the hypotensive effect of MOWE may be due to dual mechanism of central sympathetic action and direct vasodilation of blood vessel.

• Journal of Satellite, Information and Communications
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• v.12 no.4
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• pp.62-66
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• 2017

In this paper, we present the development of communication and data processing strategy for the electromagnetic wave precipitation gauge system. The electromagnetic wave precipitation gauge system is a small system for deriving area rainfall rates within 1 km radius through dual polarization radar observation at 24GHz band. It is necessary to take consider for measurement of accurate precipitation under limited computing resources originating from small systems and to minimize the use of network for the unattended operation and remote management. To overcome computational resource limitations, we adopted the fuzzy logic for quality control to eliminate non-precipitation echoes and developed the method by weighted synthesis of various rain rate fields using multiple radar QPE formulas. Also we have designed variable data packets rules to minimize the network traffic.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.04a
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• pp.290-300
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• 2000

One of the most important topics in attentional and emotional modulation of cardiac responses is time course of cardiac chronotropic response. The reason lies in dual innervation of heart, which leads to occurrence of several phases of cardiac response during exposure to affective stimuli, determined by the balance of sympathetic and parasympathetic influences. Cardiac chronotropic reactivity thus represents quite effective measure capable to trace the moment when attending and orienting processes (i.e., sensory intake of stimulus) prime relevant behavioral response (ile., emotion with approach or avoidance tendencies). The aim of this study was to find the time course of heart rate (HR) responses typical for negative (disgust, surprise, fear, anger) and positive (happiness, pleasant erotic) affective pictures and to identify cardiac response dissociation for emotions with different action tendencies such as "approach" (surprise, anger, happiness) and "avoidance" (fear, sadness, disgust). Forty college students participated in this study where cardiac responses to slides from IAPS intended to evoke basic emotions (surprise, fear, anger, sadness, disgust, happiness, pleasant-erotic). Inter-beat intervals of HR were analyzed on every 10 sec basis during 60 sec long exposure to affective visual stimuli. Obtained results demonstrated that differentiation was observed at the very first 10s of exposure (anger-fear, surprise-sad, surprise-erotic, surprise-happiness paris), reaching the peak of dissociation at 30s (same pairs plus surprise-disgust and surprise-fear) and was still effective for some pairs (surprise-erotic, surprise-sad) even at 50s and 60s. discussed are potential cardiac autonomic mechanisms underlying attention and emotion processes evoked by affective stimulation and theoretical considerations implicated to understand the role of differential cardiac reactivity in the behavioral context (e.g., approach-avoidance tendencies, orienting-defense responses).

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.4
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• pp.285-294
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• 2000

To investigate the effect of Mycorrhiza (Glomus intradics) and Rhizobium inoculation on the N, P utilization and growth response of Alfalfa (Medicago saliva L.) and Perennial ryegrass (Lolium perenne L.) in mixed sward, four treatments (non-inoculation, Control; Mycorrhiza inoculation: M; Rhizobium inoculation, R and Mycorrhiza and Rhizobium inoculation, M+R) were applied. The associated analyses were canied out on the early vegetative growth stage (DAS 56, 56 days after seeding) and on the early flowering stage (DAS 126). The decreased rate of total N and P content in soil, with advancing plant growth, was relatively higher in the M and M + R treatment than control. The content of availabie phosphorus in soil at DAS 126 increased by about 34 and 38 % in M and M+R treatment compared to control (189.2 mg PzOskg DM), while non-significant changes was observed in R treatment. Total N uptake and P uptake in the control at DAS 126 were 44.71 and 3.52 mglplant in mixed sward, respectively. About 71, 98 and 197 % of increases in total N uptake and 70, 72 and 11 1 % of increases in total P uptake were estimated in M, R and M+R treatment. Comparing to control, total dry matter yield significantly increased by 27, 33 and 53 %, and crude protein yield also by 78, 83 and 204 %, respectively, in M, R and M+R treatment. The present data indicated that mycorrhiza orland rhizobium inoculation improved N, P utilization of both alfalfa and perennial ryegrass plants, and consequently increased total yield (especially by dual inoculation, M+R). (Key words : Alfalfa, Perennial ryegrass, Mycorrhiza, Rhizobium, N and P Utilization, Growth, Yield)

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.170-175
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• 2010

A total of 24 isolates of S. homoeocarpa were isolated from 16 golf courses in Korea. Chemical resistance of 24 isolates was determined by in vitro fungal growth on fungicide-amended media with thiophanatemethyl (Benzimidazole fungicide family), tebuconazole (demethylation inhibitor fungicide family: DMI), and iprodione (dicarboximide fungicide family). Results indicated that 83.3% of 24 isolates were resistant to iprodione, 62.5% resistant to thiophanate-methyl and 0% resistant to tebuconazale. The dual resistance of iprodione and thiophanate-methyl was 58.3.%. Occurrence rate of fungicide resistance of thiophanate-methyl and iprodione had no relation to turfgrass varieties and isolated locations of pathogen. In the filed test, procymidone, boscalid, and fluquinconazole+pyrimethanil effectively controlled the dollar spot of creeping bentgrass.