• Journal of Labour Economics
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• v.25 no.3
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• pp.1-34
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• 2002

This paper investigates the effects of hours reduction on growth, investment, and consumption as well as employment. We adopt the basic framework of the indivisibility of labor developed by Hansen (1985) and Rogerson (1988) and extend it by allowing heterogeneity of workers in productive efficiency. On the basis of monthly panel data constructed from Economically Active Population Surveys and Household Income and Expenditure Surveys, we estimate the value of productive efficiency parameter of newly hired workers relative to existing workers by considering differences between the two groups in unobservable as well as observable worker characteristics. Numerical simulation of steady states demonstrates that reduction of statutory weekly hours from 44 to 40 leads to a rise in employees by 4.9 percent. However, GNP, investment, and consumption are all reduced by 2.03 percent, which is attributed to reduction in the amount of effective labor input, which in turn comes from reduction of actual average hours and productivity differences between exiting and newly hired workers.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.6
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• pp.594-598
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• 2008

In this paper we propose a fast booting technique based on Improved snapshot boot in embedded Linux, widely adopted in personal devices such as PDA and mobile phones. The existing Snapshot boot technique tries to create a snapshot image at the time of suspend, and later load the entire snapshot image into the system memory at the predefined location with the help of a bootloader at the time of resume. Since a bootloader has to copy the entire snapshot image into the predefined memory to resume the previous suspended computing state, a little bit long time is required to resume. Improved snapshot boot does not create a snapshot image consisting of whole memory pages at the time of suspend, thus resulting in smaller snapshot image than the existing snapshot boot. The remaining pages are in the swap area. The resulting smaller sized snapshot image enables much faster booting latency. Through the experiment, we can see the booting latency is reduced almost 30% with suspend image of 2982 pages. This result depends on the amount of swap-out pages.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.5
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• pp.11-23
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• 2022

For the design of the shortened ED(Expansion Deflection) nozzle, a numerical study of ED nozzle was performed according to the length reduction methods. The first method is to reduce the extension length of the ED nozzle with 80% bell nozzle length by 10%, 20% and 30%. The second method is to shorten the extension length by increasing the nozzle throat angle. Due to the increase in the curvature of the contour as the length shortened, the decrease in the nozzle exit velocity between the ED nozzle with 80% bell nozzle length and the ED nozzle in the first method was reduced, and the thrust become similar. The ED nozzle of the second method increased the thrust by increasing the nozzle exit velocity compared to the ED nozzle with 80% bell nozzle length.

• Journal of Life Science
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• v.18 no.11
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• pp.1532-1537
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• 2008

The purpose of this study was to investigate the effect of different arthroplasty designs on knee kinematic and lower limb muscular activation for up-stair and down-stair movement. 3-D video analysis of whole body and joint kinematics and EMG analysis of quadriceps and hamstrings were conducted. One-way ANOVAs were used for statistical analyses (p=0.05). The single-radius group exhibited more arthroplasty limb quadriceps EMG and hamstring coactivation EMG than the multi-radius group. Single-radius demonstrated more abduction angular displacement and reached peak abduction earlier than the multi-radius arthroplasty limb. The single- radius the percent body fat showed similar values in the Elderly, Single and Multi-radius group among the periods, however Control group was Lowered among the periods. Single-radius group limb also increased the quadriceps muscle activation level to produce more knee extension moment to compensate for the short quadriceps moment arm. Resting metabolic rate was significantly increased in control group in the period of LI. Energy expenditure was extremely increased in all groups except control group among the periods. We can say this is the exercise effects.

• Journal of the KSME
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• v.51 no.8
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• pp.34-38
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• 2011

이 글에서는 기계류 부품의 개발 기간 및 수명주기의 단축과 고성능화를 요구하고 최근의 산업흐름 현실 속에서 신뢰성 향상을 위한 종합적인 품질보증 신뢰성평가 기법과 시험비용 및 평가시간 단축을 위한 가속수명시험법 개발 추진체계 등 기술 현황에 대하여 소개하고자 한다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.10a
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• pp.118-121
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• 2000

본 연구는 반도체 생산에서 제조공기 단축과 생산 능력의 극대화를 동시에 추구하는 스케줄링에 관한 연구이다. 반도체 공정에서의 생산능력은 사진 공정 안에 있는 병목 설비에 의존한다. 본 연구는 사진 공정의 병목 설비인 스테퍼의 효율적인 스케줄링을 생성하여 제조 공기의 단축과 생산량의 최대화를 위한 선형 계획법 모델을 제시하였다.

• 프린팅코리아
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• v.11 no.8
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• pp.140-143
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• 2012

일본의 전 산업계는 지난해 발생한 동북대지진의 여파로 2년째 전력 사용감축에 나서고 있다. 자의반 타의반이라는 시선도 있지만, 일본 인쇄업도 정부의 지침에 따른 강제적인 조업시간 단축 및 조정에 나서고 있다. 자발적으로 나선 에너지 사용량 감축은 아니었지만, 조업시간 단축 및 조정의 결과로 비용 절감에 도움이 되고, 나아가 기업의 체질 개선에도 효과가 있는 것으로 나타났다.

• The Korean Journal of Pharmacology
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• v.21 no.2
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• pp.90-98
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• 1985

1) In the study of the forced-swimming test in mice (FSM), the duration of immobility posture was dose-dependently shortened by ${\alpha}_2$-agonists, clonidine and guanabenz. BH-T 933 and oxymetazoline also decreased it . Xylazine rather increased the immobility duration at low dose. 2) ${\alpha}_1$-Agonists, cirazoline, amidephrine and methoxamine, however, showed inconsistent effect on the immobility duration (ID). 3) The decrease in ID by clonidine and guanabenz was antagonized by pretreatment with yohimbine, idazoxan and phentolamine (${\alpha}_2$antagonist), but not by prazosin and corynanthine (${\alpha}_1$-antagonist) .4) The ID in the FSM was shortened dose-dependently by d-amphetamine, and it was also antagonized by yohimbine, but not by prazosin. 5) In the mice pretreated with either ${\alpha}$-methyl-p-tyrosine or reserpine, or with combination of both, the decrease in ID was still evoked by clonidine. 6) When the mice were chronically treated with antidepressants (desipramine and imipramine), or with electroconvulsive shock, clonidine still decreased the ID as it did in the control. 7) These results provided the evidences to hypothesize that the change of the ID in the FSM is closely related with the postsynaptie ${\alpha}_2$-adrenoceptor located on the central noradrenergic neuron body. Furthermore, it is assumed that this escape-directed behavior enhanced by ${\alpha}_2$-adrenoceptor agonist may be the result in some analogy with the incentive of drives which are directed toward the self-preservation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2D
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• pp.193-201
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• 2011

The provision of traffic information plays an important role in increasing social benefit not only by saving travel time for individuals but also by improving the efficiency of road operation. VMS(Variable Message Sign) helps on-wheel drivers easily understand the road situation, and also provides real-time traffic information to people on the streets. However, it has not been sufficiently studied on how traffic information based on VMS influences on the drivers' selection of route. This study investigated how drivers use VMS traffic information and how they are satisfied with it. Then, the model of drivers' route selection was specified with the types of traffic information and the expected travel time to examine the influence on the selection of drivers' route. The model was estimated and analyzed in three types according to the condition of detour roads, and the rate of route change and the degree of sensitivity was calculated from the estimation. The results of analysis are as follows. the $1^{st}$ type model showed the 10% of route change for the travel time saving of 5minutes, and the 81.6% of route change for the travel time saving of 20minutes. The $2^{nd}$ type led to the range of route change from 14.2% to 92.7% over the 5 through 20 minutes of travel time saving. The $3^{rd}$ model resulted in the 99.1% of route change. The sensitivity of route change showed the highest for the travel time saving of 11 minutes with the $1^{st}$ type model, 9 minutes with the $2^{nd}$ type model, and 5 minutes with the $3^{rd}$ type model respectively.

• Clinical and Experimental Reproductive Medicine
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• v.12 no.1
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• pp.31-40
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• 1985

월경주기 중 황체기가 짧은 여성 즉 황체기 단축현상을 가진 한국여성(SLP) 의 특성을 조사하고 진단하는 방법을 개발하기 위하여 본 실험을 행하였다. 재료는 정상 월경주기를 가진 12명의 여성에서 26주기와 8명의 황체기 단축현상을 가진 여성에서 17주기를 선택하였다. 기상후 첫 오줌에서 steroid glucuronides의 농도를 측정하여 비교한 결과는 다음과 같았다. SLP 의 estrone -3 -glucuronide ($E_1G)의 농도는 초기 여포기와 황체기 동안 정상인에 비하여 현저히 낮았다. 또한 SLP 의 전 월경기 중 pregnanediol-$3{\alpha}$-glucuronide($P_2G$)의 농도 역시 유의성있게 낮았다. 그러나 $E_1G/P_2G$의 비율은 여포기가 황체기에 비하여 현저히 높았고, SLP 여성의 비율이 정상인 보다 각 월경주기 중 유의성있게 높았다. 위의 결과로 보아 $E_1G$, $P_2G$및 $E_1G/P_2G$의 농도차로 황체기 단축현상을 가진 여성을 진단 하고 또 치료시 난소의 기능조절에 이욜될 수 있을 것으로 사려된다.