• The Journal of Korean Institute of Communications and Information Sciences
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• v.13 no.5
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• pp.422-428
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• 1988

An iterative learning control system is a control system which makes system outputs follow desired outputs by iterating its trials over a finite time interval. In a discrete time system, we proposed one method in which present control inputs can be obtained by a linear combination of the input sequence and time-shifted error sequence at previous trial. In contrast with a continous time learning control system which needs differential opreration of an error signal, the time shift operation of the error sequence is simpler in a computer control system and its effectiveness is shown by a simulation.

• Communications for Statistical Applications and Methods
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• v.3 no.1
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• pp.21-27
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• 1996

A testing procedure is considered to the problem of testing whether there exists a shift in scale at an unknown time point whem a fixed number of observations are drawn successively in time. A test statistic based on squared ranks test for equal variances is suggested and its aymptotic distrbution is dereived. Small sample power comparisons are performed.

• Korean Journal of Community Nutrition
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• v.7 no.5
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• pp.615-627
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• 2002

The purpose of this study was to examine the eating habits and nutrient intake of industrial workers who work day and night shifts. In the area of percentage of skipped meals, the day shift workers responded that they usually skipped breakfast and the night shift workers often skipped lunch and dinner. The day shift workers answered that they skipped meals because of lack of time. The night shift workers cited poor appetite as their main reason for skipping meals. The intake of calories, Vitamin $B_2$ and calcium of the industrial workers who worked day and night shift was lower than the Korean RDA. The intake of iron of the male night shift workers was lower than the Korean RDA The intake of calories, protein, calcium, iron, Vitamin $B_2$and niacin, vitamin C of the female night shift workers was lower than the Korean RDA. In the area of nutrient intake, the night shift workers both male and female got lower scales than the day shift workers. The nutrient intake of the female night shift workers was the worst. Because they cook for themselves and live alone, their nutrient intake and eating habits were bad. The night shift workers were worse than the day shift workers and the female night shift workers were the worst. Considering the above results, night shift workers should correct their poor eating habits, their nutrient intake and have a well-balanced diet.

• Journal of the Ergonomics Society of Korea
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• v.25 no.4
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• pp.1-7
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• 2006

The purpose of this study is to develop an efficient algorithm for the management of the shift schedule in nuclear power plants in consideration with the ergonomic criteria and the regulatory codes. The ergonomic criteria considered are the work hours, overtime-work frequency and working time, start and finishing time of works, allocation of rest times and duty-offs, rotating of shifts, etc. to comply with the regulations such as the Labor Standard Act, the ILO Convention No. 171, 178, "the detailed content of a periodic safety review," enforcement regulations 19-2 of the Atomic Energy Act. The developed algorithm for the shift schedule program adopts a heuristic method to minimize the difference the workload for shift workers in nuclear power plants.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.4
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• pp.145-152
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• 2019

All machines deteriorate in performance over time. The phenomenon that causes such performance degradation is called deterioration. Due to the deterioration, the process mean of the machine shifts, process variance increases due to the expansion of separate interval, and the failure rate of the machine increases. The maintenance model is a matter of determining the timing of preventive maintenance that minimizes the total cost per wear between the relation to the increasing production cost and the decreasing maintenance cost. The essential requirement of this model is that the preventive maintenance cost is less than the failure maintenance cost. In the process mean shift model, determining the resetting timing due to increasing production costs is the same as the maintenance model. In determining the timing of machine adjustments, there are two differences between the models. First, the process mean shift model excludes failure from the model. This model is limited to the period during the operation of the machine. Second, in the maintenance model, the production cost is set as a general function of the operating time. But in the process mean shift model, the production cost is set as a probability functions associated with the product. In the production system, the maintenance cost of the equipment and the production cost due to the non-confirming items and the quality loss cost are always occurring simultaneously. So it is reasonable that the failure and process mean shift should be dealt with at the same time in determining the maintenance time. This study proposes a model that integrates both of them. In order to reflect the actual production system more accurately, this integrated model includes the items of process variance function and the loss function according to wear level.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.11
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• pp.2733-2737
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• 2014

Motion detection according to the movement and the change area detection method according to the background difference and the motion history image for use in a motion estimation technique using a real-time image, the motion detection method according to the optical flow, the back-projection of the histogram of the object to track for motion tracking At the heart of MeanShift center point of the object and the object to track, while used, the size, and the like due to the motion tracking algorithm CamShift, Kalman filter to track with direction. In this paper, we implemented the motion detection algorithm based on color and shape information of the object and verify.

• The Journal of Korean Physical Therapy
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• v.29 no.5
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• pp.255-258
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• 2017

Purpose: This study aimed to investigate the effects of compelled weight shift in paretic lower limb training on balance ability in patients with stroke. Methods: Thirty-six individuals with hemiparesis, who were randomly assigned to a 10CWST (10 mm constrained -weight shift training) group, a 5CWST (5 mm constrained-weight shift training) group, and a control group participated in this study. Compelled weight shift training was performed in 3 sets of 5 min with a rest period of 1 min between sets. Both the 5CWST and 10CWST groups performed 5 times per week for 4 weeks. Static (mediolateral and anteroposterior sway velocities) and dynamic balance (mediolateral and anteroposterior distances) was assessed using the Good Balance system. Results: Significant differences were found in the M-L and A-P sway velocities, and the M-L sway distance. The M-L and A-P sway velocities, and M-L sway distance showed significantly large group effects (p<0.05), time effects (p<0.05), and group-by-time interaction (p<0.05). The post hoc analyses indicated that, following intervention, the 10CWST group showed more significant changes in the M-L and A-P sway velocities, and the M-L sway distance than the control group. Conclusion: These results suggest that the use of compelled weight shift in paretic lower limb training may be an effective method to improve balance ability in patients with stroke.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.514-517
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• 2008

Water gas shift(WGS) is an important step in fuel process for fuel cells, and improperness of commercial WGS catalysts for use in fuel cell systems has prompted numerous researches on noble metal catalysts. A selected noble metal catalyst for water gas shift reaction(WGS) was prepared with various metal loadings. The prepared catalysts were tested under two feeding conditions. At moderate residence time, carbon monoxide conversion was much higher on the noble metal catalysts as compared to commercial high-temperature shift catalyst. Effects of metal loading were examined by activity tests at short residence time. Higher metal loading effected higher reaction rate. The kinetic data was fitted to simple reaction equations and effectiveness factor was estimated. The results suggest the necessity of a structural design for the highly active noble metal catalysts.

• Journal of Korean Academy of Nursing Administration
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• v.6 no.1
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• pp.55-81
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• 2000

This study examined nursing care in a Newborn Intensive Care Unit (NICU) by reviewing nursing activities for the newborns. Through direct observation, time used for nursing care according to the nursing activity, shift, day of the week, and position of the nurses was measured. This study was done on November 15, 21, 24, 1999 at a university medical center hospital and included eight nurses and 179 newborns as the study subjects. The data were collected from the medical records, and by using a nursing activity record for the NICU, and a nursing activity time record for the NICU. The first step in the data collection process was to develop a list of nursing activities which was done through a literature review, examination of medical affairs and duty records. Content validity was measured by a panel of three professors who were experienced clinicians. In the second step two pre-training sessions were held with three sophomore student nurses who then measured the time for each nursing activity using a stopwatch. The data were analyzed using frequencies for nursing activities, averages, percentages and ANOVA for differences between shift and between days of the week, and percentages and t-test for differences according to position of the nurse. The results are as follows: 1) The total number of activities was 156, direct or indirect nursing activities. Direct nursing activity classified according to physical, educational, emotional/social/economic/spiritual needs. There were 109 direct nursing activities in 16 fields. 2) The order of nursing activities, according to time required, was record keeping, nutritional care, measurement/observation, medication, hygiene care, examination and specimen collection, and checking supplies, and according to frequency, measurement/ examination, record keeping, nutrition care, hygiene care, elimination care and medication. 3) According to shift, direct care during the night shift at 313.4 minutes was the longest time and indirect nursing care during the night shift at 252.2 minutes was the highest time. 4) For days of the week, Monday had the highest time for direct care 275.8 minutes (34.6%) and Wednessday had the highest time for indirect nursing care 269.6 minutes (36.1%). 5) For nursing time according to position of nurse, general nurses had the highest for direct care (330.7 minutes), nurse managers for indirect nursing activities (239.0 minutes) and general nurses for individual private time (63.9 minutes). The results of this study show that the major nursing time consuming activities included record keeping, nutrition care and measurement/examination. For newborns, time needs to be allowed for care to be sensitive, sophisticated and specialized rather than concentrated on indirect nursing tasks such as record keeping. Therefore, it is imperative to develop computerized systems that support a systematic approach to record keeping which is more efficient. Moreover, nursing needs according to shift, day or position of nurse can be utilized in assessing nursing resources through a computerized process.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.7
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• pp.387-393
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• 2016

Threshold voltage shift has been observed from many thin-film transistors (TFTs) and the time evolution of the shift can be modeled as the stretched-exponential and -hyperbola function. These analytic models are derived from the kinetic equation for defect-creation or charge-trapping and the equation consists of only reversible reactions. In reality TFT's a shift is permanent due to an irreversible reaction and, as a result, it is reasonable to consider that both reversible and irreversible reactions exist in a TFT. In this paper the case when both reactions exist in parallel and make a combined threshold voltage shift is modeled and simulated. The results show that a combined threshold voltage shift observed from a TFT may agrees with the analytic models and, thus, the analytic models don't guarantee whether the cause of the shift is defection-creation or charge-trapping.