• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.5
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• pp.110-120
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• 1994

Due to the increasing demands in comfortable drivability, most motor companies are developing their own unique shift controller to suppress the shift shock induced by gear change. For a typical automatic transmission system, the dynamic constraints of friction clutch was clarified for efficient program development and major factors effecting the shift transient was confirmed by simulation study. The MIMO LQG/LTR controller was designed to control the turbine and corresponding gear speed. By establishing the control strategy recalling transient response during shift the speed controller mentioned above was used as an indirect torque controller. Consequently a new concept for a systematic design method of shift controller applicable to wide-varying systems was suggested which is time efficient and cost efficient saving a lot of experimental study.

• Journal of the Ergonomics Society of Korea
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• v.22 no.3
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• pp.13-26
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• 2003

The purpose of this study is to investigate the present conditions of the night work and shift work systems in the heavy chemical industrial complexes found in Changwon, Masan, and Chinhae. Korea. We will attempt to define and classify their problems; and to discover further ways to improve their systems. Fifty production factories were carefully selected as the subjects for this study. The shift systems were classified into five categories. The consecutive night shifts were long in almost all cases with 6 days (36 factories) and 7 days (13 factories). It was found that the night work of about] 2 hours continues for a long period in the weekly rotation full-day shift systems and the night-including non-full-day shift systems, and there was no holiday during a shift cycle in the continuous full-day shift systems. The work time in most shift systems was longer than the 44-hours/week permitted by Korean law. Considering the characteristics of these various types of shift systems, the most essential thing to reduce the shift workers' work load may be to shorten their working hours and improve the schedule of shift systems. It is highly recommended as a fundamental solution. to reduce the portal-to-portal hours from 12 to 8 in the night-including non-full-day shift systems and the weekly rotation full-day shift systems, and at least to employ a 4-team 3-shift system in the continuous full-day shift systems. In addition to this, it should from now on be taken as a goal to restructure the types of shift systems by taking such measures as avoiding continuous night work if possible, providing sufficient off-duty intervals both before and after night shift, providing increased opportunities for workers to nap during night work. and increasing the number of holidays.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.3
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• pp.118-126
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• 2010

The automated mechanical transmission(AMT) is composed of electronic control management(ECM) and automatic shift gear(ASG). The AMT has advantages which are high efficiency of manual transmissions(MT) and offer operation convenience similar to automatic transmissions(AT). However, it has defects that are the torque gap during gear shift transients and shift time is long. To reduce such defects, it is necessary practically to evaluate error and characteristics as developing simulation model before the control algorithm is applied. In this paper, models are composed of vehicle model and AMT shift control model. Particularly AMT shift control model consists of main clutch management model (MCM) and shift control management model(SCM). The developed models were verified by comparing the simulated and experimental results under the same operational conditions. It can also be used to evaluate shift algorithm.

• English & American cultural studies
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• v.9 no.1
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• pp.221-237
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• 2009

This paper analyzes the time-shift technique in Joseph Conrad's Lord Jim. Conrad's manipulation of time in this novel is based on his aspiration for how 'to make you see,' which he believes is completed through the harmony form and substance in his works. So Conrad applies this technique which was used earlier by some writers such as Laurence Sterne to his Lord Jim to show its theme more effectively. In Lord Jim, the story consists of two parts; first, Jim jumps from a ship called the Patna and is deprived of his navigation certificate. Secondly, he wins the people's respect in Patusan in which his past related to the Patna remains hidden, but he faces his death by taking responsibility for the death of the chief's son in the island. These events in Lord Jim are not described in chronological order; that is, some events are depicted with the time-shift technique using flashback, association, or fragmentary memory to accelerate the speed of stories as well as to offer the actuality of the events. With this structure, the themes of Jim's story have something to do with his heroic actions and failures. Jim wants to be a hero and after failures he struggles to redeem himself only to fail. In particular, Jim's jump from the Patna is emphasized through the time-shift and it shows there is something incomprehensible in his action. Therefore, Conrad reveals in Lord Jim that Jim is one of us who not only are imperfect but also have the weaknesses inside that can unexpectedly emerge in an instant.

• Journal of Nutrition and Health
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• v.40 no.6
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• pp.576-583
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• 2007

The purpose of this study was to assess the daily steps, physical activities and activity coefficient of policemen (average age: 31.5 ${\pm}$ 5.1 years) who do shift work. Body weight, height and daily steps were measured and one-day activity diary was collected by interviewing with policemen. Average height, body weight, BMI, body fat (%) and muscles (%) of subjects were 173.1 ${\pm}$ 5.2 cm, 73.7 ${\pm}$ 9.7 kg, 24,6 $kg/m^{2}$, 15.5 ${\pm}$ 1.9% and 37.3 ${\pm}$ 5.8%, respectively. The average daily numbers of steps were found to be 9,812 steps/day on day shift duty and 10,888 steps/day on night shift duty and 6,551 steps/day on holiday duty. Hourly step rates on day shift, night shift and holiday came to 1946 steps/hr, 2,130 steps/hr and 1,318 steps/hr, respectively. Activity coefficient (1.75) in night shift of the subjects was the highest and activity coefficient (1.52) in day shift was significantly higher than that (1.31) in holiday (p < 0.05). The rate of expending time for very light activity in holiday (91.5%) was significantly higher than that (70.0%) in night shift. The muscle mass (kg, %) had significantly positive relationship with daily steps in day shift (r = 0.592, r = 0.632) and night shift (r = 0.550, r = 0.503). Triceps skinfold thickness was negatively correlated with daily steps in day shift (r = -0.366, p < 0.05). There were remarkable differences in physical activities and sleeping hours depending on shift works of policemen. In the case of night shift work, sleeping hours was the lowest and activity coefficient was the highest among day shift, night shift and holiday. These results suggest that energy requirements of policemen should be differentiated according to shift work duty.

• International Journal of Automotive Technology
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• v.7 no.2
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• pp.161-166
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• 2006

This paper presents shift characteristics of a dual clutch transmission(DCT). To obtain the shift force, dynamic models of the DCT are constructed by using MATLAB/Simulink and considering the rotational inertia of every component and the target pre-select time. Dynamic models of the shift and clutch actuators are derived based on the experimental results of the dynamic characteristics test. Based on the dynamic model of the DCT synchronizer, control actuator and vehicle model, a DCT vehicle performance simulator is developed. Using the simulator, the shift force and speed of the relevant shafts are obtained. In addition, the torque and acceleration of actuators are calculated during the shift process by considering the engaging and disengaging dynamics of the two clutches. It is observed from the performance simulator that uninterrupted torque can be transmitted by proper control of the two clutches.

• Journal of the Ergonomics Society of Korea
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• v.29 no.3
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• pp.337-345
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• 2010

The purpose of this study was to investigate the effects of sleep/wake behavior for shiftwork in air traffic controllers (ATCs) using wrist actigraph for ten workers on a continuous full-day three-team three-shift system of forward rotation including on-duty and off-duty periods. The wrist actigraph data were recorded for three days (one shift cycle) for each subject. The mean activity counts during an on-duty period progressively increased from the night, the swing, to the morning shifts. The doze length during on-duty periods showed decreases in the morning and swing shifts as compared to the night shift. Total sleep time (TST) and sleep efficiency (SE) during off-duty periods increased in the morning-1 and swing-night shift compared to the morning-2 shift. Finally, I discussed the role of doze-taking during the burden on night shift ATCs.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.2
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• pp.92-97
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• 2013

In this paper the author proposes a method of implementing a numerical model for threshold voltage ($V_{th}$) shift in organic thin-film transistors (OTFTs) into SPICE tools. $V_{th}$ shift is first numerically modeled by dividing the shift into sequentially ordered groups. The model is then used to derive a simulations model which takes into simulation parameters and calculation complexity. Finally, the numerical and simulation models are implemented in AIM-SPICE. The SPICE simulation results agree well with the $V_{th}$ shift obtained from an OTFT fabricated without any optimization. The proposed method is also used to implement the stretched-exponential time dependent $V_{th}$ shift in AIM-SPICE and the results show the proposed method is applicable to various types of $V_{th}$ shifts.

• Journal of IKEEE
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• v.16 no.1
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• pp.51-55
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• 2012

In this paper, we propose to employ a ternary sequence as a cyclic code shift keying (CCSK) modulation sequence. And we simulate the performance in a frequency hopping spread spectrum/time division multiple access (FHSS/TDMA) system with CCSK. Wireless channel is modeled as Rayleigh fading channel. From the simulation results, it is demonstrated that the system adopting the ternary sequence as a CCSK sequence has higher performance than that with a random sequence.

• Aerospace Engineering and Technology
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• v.11 no.1
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• pp.103-110
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• 2012

In the COMS satellite mission operation, more large meteorological images such as Full Disk(FD) image or 2 adjacent Extended Northern Hemisphere(ENH) images can be taken by the time shift of East West Station Keeping(EWSK) maneuver when the EWSK conflicts with the large images. In this study an analytical approach based on probability of the conflict is proposed for theoretical analysis about the EWSK time shift to avoid the conflict with FD or 2 ENH images. The EWSK time shift has been applied to the COMS operation as a test, too. The theoretical study result and test operation outcome are synthesized to provide the analysis of impact on the COMS fuel consumption by the EWSK time shift. This study is expected to contribute to the maximization of COMS meteorological mission application.