• Journal of Korean Clinical Nursing Research
• /
• v.16 no.3
• /
• pp.133-144
• /
• 2010

Purpose: This study intended to evaluate the intermediate effects of using Electronic Nursing Record System which was introduced 4 years and 4 months ago. Methods: Participants were 65 nurses engaged in 3 shifts in a general hospital. The specific methods were identification of nursing activity times by means of nurses' self-recording in structured forms, survey of user satisfaction using questionnaires, and examination of nurses' responses to open-ended questions about using the system. Results: The direct nursing activities took more than 50% of the time during day and evening shifts. In night shift, direct nursing activities took more than 41% of the time. Comparing to the initial evaluation, measured at 10 months after the introduction, the time spent in indirect nursing activities have decreased about 10% in each shift. The user satisfaction was 3.54 points which was higher than 3.33 points measured at 10 months after the introduction. The nurses recommended some changes needed in the current system to make it better, such as speeding up the system. Conclusion: The intermediate evaluation shows reduced indirect nursing time, increased direct nursing time, and improved user satisfaction.

• Journal of applied mathematics & informatics
• /
• v.5 no.1
• /
• pp.1-12
• /
• 1998

We consider G/M/1 queues with multiple vacation disci-pline where at the end of every busy period the server stays idle in the system for a period of time called changeover time and then follows a vacation if there is no arrival during the changeover time. The vaca-tion time has a hyperexponential distribution. By using the methods of the shift operator and supplementary variable we explicitly obtain the queue length probabilities at arrival time points and arbitrary time points simultaneously.

• Journal of Korean Clinical Nursing Research
• /
• v.16 no.1
• /
• pp.95-105
• /
• 2010

Purpose: The purpose of this study was to examine the difference between direct and indirect nursing activity times according to the grade of nursing management fee. Methods: The subjects of this study were 324 working nurses at the time of 3rd grade and 319 working nurses at the 2nd grade of nursing management fee in one university hospital. Nursing activity time was measured in April and May, and in September and October of 2008 for comparison. The data were analyzed by SPSS win using frequency and t-test. Results: Direct nursing care activity time per one patient was significantly higher at 2nd grade than 3rd grade in day shift (t=-2.55, p=.012). Direct nursing care workload per one nurse was significantly lower at 2nd grade than 3rd grade in evening shift (t=2.21, p=.030), whereas indirect nursing care workload was lower at 2nd level in night shift (t=2.43 p=.016). Conclusion: The findings from this study showed that higher nurse-to-patient ratio can provide greater amount of direct nursing care activity for the patient. Also, it decreased workload of nurses. The higher nurse-to-patient ratio will be beneficial for promoting quality of nursing care as well as decreasing nurse's heavy workload.

• Korean Journal of Psychosomatic Medicine
• /
• v.29 no.2
• /
• pp.111-120
• /
• 2021

Objectives : Shift work has been known to cause various health problems by making it difficult for humans to adapt to their natural circadian rhythms. In particular, shift workers tend to complain of sleep difficulties associated with work schedules, and sometimes use alcohol as a self-medication to induce sleep. To date, no clear mechanism has been identified regarding the link between shift work and sleep, between shift work and drinking. This study aims to confirm the relationship between shift work and sleep, and to analyze whether the change in sleep caused by shift work causes drinking. Methods : This study included 11360 people (5704 men and 5656 women) among the Korean National Health and Nutrition Survey data in 2014, 2016 and 2018. The work type between 6am-6pm was defined as day work, and other work types were defined as shift work. Using logistic regression analysis, the relationship between shift work and sleep quality, shift work and high risk drinking, drinking amount at 1 time, drinking frequency were analyzed. In addition, we analyzed whether sleep mediates the relationship between shift work and drinking using mediated analysis. Results : Shift work showed a significant negative relationship with sleep quality in men and women (male OR=1.37, 95% CI 1.11-1.70, female OR=1.26, 95% CI=1.05-1.50). There was no significant relationship between shift work and alcohol in the case of men, but in the case of women, there was a significant positive relationship between shift work and the number of alcohol consumption (OR=1.34, 95% CI=1.04-1.72). When mediation analysis was conducted, it was found that women's sleep quality partially mediated the relationship between shift work and the frequency of drinking. Conclusions : The results of this study suggest that shift work causes sleep difficulties, and in the case of women, drinking can be induced through the partial mediating effect of sleep. Considering that women are more likely to choose drinking as a coping method for sleep problems, more active interventions for female shift workers are needed.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.48 no.2
• /
• pp.69-75
• /
• 1999

The characteristics of $H_2$ gas detection have been investigated using the Pt-MIS capacitor composed of the LPCVD nitride on the oxide. The flat band voltage shift is measured as 0.1 V in 1,000 ppm $H_2$ gas ambient and to be independent of Pt catalyst thickness. It is found that the flatband voltage shift is proportional to the hydrogen concentrations. The response and recovery time of Pt-MIS capacitor are 5 mins and 25 mins respectively. The samples of 30nm thick Pt revealed much higher sensitivity than that of 150nm samples. The samples of 150nm Pt showed that the flatband voltage shift of the device is due to the formation of the dipole layer of the adsorbed hydrogen atoms at the Pt-insulator interface.

• Proceedings of the KSME Conference
• /
• 2001.11a
• /
• pp.723-729
• /
• 2001

Electro-hydraulic shift control of a vehicle automatic transmission has been predominantly carried out via an open-loop control based on numerous time-consuming calibrations. Despite remarkable success in practice, the variations of system characteristics inevitably deteriorate the performance of the tuned open-loop controller. As a result, the controller parameters need to be continuously updated in order to maintain satisfactory shift quality. This paper presents a self-learning algorithm for automatic transmission shift control in a construction vehicle during inertia phase. First, an observer reconstructs the turbine acceleration signal (impossible to measure in a construction vehicle) from the readily accessible turbine speed measurement. Then, a control algorithm based on a quadratic function of the turbine acceleration is shown to guarantee the asymptotic convergence (within a specified target bound) of the error between the actual and the desired turbine accelerations. A Lyapunov argument plays a crucial role in deriving adaptive laws for control parameters. The simulation and hardware-in-the-loop simulation (HILS) studies show that the proposed algorithm actually delivers the promise of satisfactory performance despite the system characteristics variations and uncertainties.

• Journal of Environmental Science International
• /
• v.23 no.1
• /
• pp.25-37
• /
• 2014

In the present study, we analyzed precipitation patterns and diurnal variation trends of hourly precipitation intensity due to climate change. To that end, we used the hourly precipitation data obtained from 26 weather stations around South Korea, especially Busan, from 1970 to 2009. The results showed that the hourly precipitation was concentrated on a specific time of day. In particular, the results showed the so-called "morning shift" phenomenon, which is an increase in the frequency and intensity of hourly precipitation during the morning. The morning shift phenomenon was even more pronounced when a higher level of hourly precipitation intensity occurred throughout the day. Furthermore, in many regions of Korea, including Busan, this morning shift phenomenon became more prevalent as climate change progressed.

• Membrane Journal
• /
• v.20 no.3
• /
• pp.228-234
• /
• 2010

In this study, dynamic simulation of membrane reactor was performed for water gas shift reaction and temperature, hydrogen concentration, etc. were investigated as a function of time and position. Simulation results indicated that differences of hydrogen concentration, hydrogen partial pressure, and temperature in the radial direction, were larger in the entrance than in the exit. In addition, the hydrogen flux was the largest in the entrance, where the hydrogen partial pressure difference was the largest, and the conversion of carbon monoxide in the exit was about 0.65.

• Journal of Institute of Control, Robotics and Systems
• /
• v.12 no.8
• /
• pp.746-751
• /
• 2006

In this paper, we present tracking algorithm for the indoor moving object. We research passive method using a camera and image processing. It had been researched to use dynamic based estimators, such as Kalman Filter, Extended Kalman Filter and Particle Filter for tracking moving object. These algorithm have a good performance on real-time tracking, but they have a limit. If the shape of object is changed or object is located on complex background, they will fail to track them. This problem will need the complicated image processing algorithm. Finally, a large algorithm is made from integration of dynamic based estimator and image processing algorithm. For eliminating this inefficiency problem, image based estimator, Mean-shift Algorithm is suggested. This algorithm is implemented by color histogram. In other words, it decide coordinate of object's center from using probability density of histogram in image. Although shape is changed, this is not disturbed by complex background and can track object. This paper shows the results in real camera system, and decides 3D coordinate using the data from mean-shift algorithm and relationship of real frame and camera frame.

• Safety and Health at Work
• /
• v.1 no.2
• /
• pp.112-123
• /
• 2010

The paper gives an overview of the problems to be tackled nowadays by occupational health with regards to shift work as well as the main guidelines at organizational and medical levels on how to protect workers' health and well-being. Working time organization is becoming a key factor on account of new technologies, market globalization, economic competition, and extension of social services to general populations, all of which involve more and more people in continuous assistance and control of work processes over the 24 hours in a day. The large increase of epidemiological and clinical studies on this issue document the severity of this risk factor on human health and well being, at both social and psychophysical levels, starting from a disruption of biological circadian rhythms and sleep/wake cycle and ending in several psychosomatic troubles and disorders, likely also including cancer, and extending to impairment of performance efficiency as well as family and social life. Appropriate interventions on the organization of shift schedules according to ergonomic criteria and careful health surveillance and social support for shift workers are important preventive and corrective measures that allow people to keep working without significant health impairment.