• Journal of the Korea Computer Industry Society
• /
• v.2 no.9
• /
• pp.1155-1162
• /
• 2001

This paper proposes a method to determine the optimal utilizations of the UNIX systems. This method is developed using the definition-the optimal utilization is the maximum allowable utilization In other words, the optimal utilization is the maximum utilization that can be allowed by users while providing tolerable response time. As the tolerable response time increases, the optimal utilization increases. Therefore, the optimal utilization is obtained at the maximal value of tolerable response time. Our analysis shows tolerable response time is achieved when the average of the trivial response time is less than 0.24 seconds for a given service objective. It also shows the optimal utilization consists of three components-%wio, %sys, and %usr. By way of example, the optimal utilizations of a machine running under the UNIX operating system are computed using proposed method.

• The Transactions of the Korea Information Processing Society
• /
• v.2 no.5
• /
• pp.807-813
• /
• 1995

This paper proposes a method to determine the optimal utilizations of the UNIX systems. This method is developed using the definition-the optimal utilization is the maximum allowable utilization. In other words, the optimal utilization is the maximum utilization that can be allowed by users while providing tolerable response time. As the tolerable response time increases, the optimal utilization increases. Therefore, the optimal utilization is obtained at the maximal value of tolerable response time. Our analysis shows tolerable response time is achieved when the average of the trivial response time is less than 0.24 seconds for a given service objective. It also shows the optimal utilization consists of three components-%wio, and %usr. By way of example, the optimal utilizations of a machine (IBM 3081) running under the UNIX operating system are computed are computed using the proposed method.

• Proceedings of the KIEE Conference
• /
• 2004.11c
• /
• pp.72-75
• /
• 2004

In this paper, the task assignment strategy considering communication delay and the priority of distributed tasks is proposed for the real-time network system in order to maximize the utilization of the system. For the task assignment strategy, the relationship among priority of tasks in network nodes, the calculation time of each task, and the end-to-end response time including the network delay is formulated firstly. Then, the task assignment strategy using the genetic algorithm is proposed to optimize the utilization of the system considering the LCM(Least Common Multiple) period. The effectiveness of proposed strategy is proven by the simulation for estimating the performance such as the utilization and the response time of the system in case of changing the number of tasks and the number of network nodes.

• Asian-Australasian Journal of Animal Sciences
• /
• v.16 no.6
• /
• pp.863-866
• /
• 2003

This study was conducted to examine the effects of dietary cellulose levels on growth, nitrogen utilization, the retention time of diets in the digestive tract, and caecal microflora of 2-month-old Single Comb White Leghorn male chickens fed 3 purified diets that contained 0, 3.5% and 10% cellulose in equal amount of nutrients for 7 days. Body weight gain and nitrogen utilization were significantly higher (p<0.05), while total microflora counts in the caecal contents and retention time of the diet in the digestive tract were significantly lower (p<0.05) in the group fed 3.5% dietary cellulose compared with the group fed 10% dietary cellulose. Body weight gain, nitrogen utilization and retention time of the diet in the digestive tract decreased significantly while the total microflora count in the caecal contents increased significantly in the group fed 10% dietary cellulose compared to the group fed 0% dietary cellulose (p<0.05). Chickens fed 10% dietary cellulose had significantly increased counts of uric acid-degradative bacteria such as Peptococcaceae and Eubacterium, including Peptostreptococcus (p<0.05). The results suggest that cellulose in purified diets is an effective ingredient and the effects on growth, nitrogen utilization, caecal microflora counts and diet retention time in the digestive tract are dependent on the inclusion rate. Positive or negative effects of dietary cellulose are displayed by growth, nitrogen utilization, caecal microflora counts and retention time of the diet in the digestive tract. Positive effects were displayed when the inclusion rate is 3.5% and negative effects were displayed when that is greater than 3.5% of the diet, and the phenomenon is without reference to the age of the chickens.

• Journal of Preventive Medicine and Public Health
• /
• v.23 no.3 s.31
• /
• pp.316-323
• /
• 1990

To analyze of determinants influencing the utilization of the rural health sub-centers (HSCs), 116 of 144 HSCs in Kyong Gi Do, were selected for this study. The self-administered questionnaire covering the environment and the characteristics of doctors working in the HSCs was sent to HSCs by mail. 105 questionnaires were returned of which 88 were completed and use in the study. The dependant variable was the total number of medical care visits to the HSCs from January 1, 1990 to March 31, 1990. Data was analyzed by multiple regression analysis. The results were as follows : First, the more time required to set from the HSCs to nearest hospital or clinic, the higher the utilization of the HSCs. Second, the more geographically accessible the HSCs was, the more utilization the HSCs. Third, the older of the HSCs doctors were, the more utilization of the HSCs. Fourth, the higher frequency of bus service from the HSCs to town, the more utilization of the HSCs. Fifth, the more time required from the HSCs to town, the more utilization of the HSCs. Therefore, the determinants influencing the utilization of the rural HSCs in Kyong-Gi Do, are mostly geographical accessibility of medical care.

• International Journal of Control, Automation, and Systems
• /
• v.4 no.5
• /
• pp.601-614
• /
• 2006

In this paper, a study on task assignment strategies for a complex real-time network system is presented. Firstly, two task assignment strategies are proposed to improve previous strategies. The proposed strategies assign tasks with meeting end-to-end real-time constraints, and also with optimizing system utilization through period modulation of the tasks. Consequently, the strategies aim at the optimizationto optimize of system performance with while still meeting real-time constraints. The proposed task assignment strategies are devised using the genetic algorithmswith heuristic real-time constraints in the generation of new populations. The strategies are differentiated by the optimization method of the two objectives-meeting end-to-end real-time constraints and optimizing system utilization: the first one has sequential genetic algorithm routines for the objectives, and the second one has one multiple objective genetic algorithm routine to find a Pareto solution. Secondly, the performances of the proposed strategies and a well-known existing task assignment strategy using the BnB(Branch and Bound) optimization are compared with one other through some simulation tests. Through the comparison of the simulation results, the most adequate task assignment strategies are proposed for some as system requirements-: the optimization of system utilization, the maximization of running tasktasks, and the minimization of the number of network node nodesnumber for a network system.

• Journal of Preventive Medicine and Public Health
• /
• v.23 no.2 s.30
• /
• pp.185-193
• /
• 1990

The purpose of this study is to observe the pattern of change in medical care utilization over time in early years of insurance coverage. The source of data is the benefit records file of a voluntary medical insurance society for covering the four-year period, from 1982 to 1985. The measure of medical care utilization used in this study is the age-sex standardized percentage of the enrollee who have visited a physician over total analytical population during a three-month period. For six cohorts by the year of enrollment ($1979{\sim}1984$), the relationship between the utilization and duration of insurance coverage was examined controlling for the calender year and season. In the analysis, logistic multiple regression and residual analysis were employed. It was observed that medical care utilization rapidly increased during the early stage of insurance coverage, and after then increased at a slower rate over time to become almost stable in about twenty months.

• Journal of the Korean Society for Railway
• /
• v.15 no.6
• /
• pp.638-644
• /
• 2012

In this study, we numerically estimated available and unavailable time of conventional railway by examining 60% which is known as average range of track utilization efficiency. We also estimated track repair time for maintenance which is the main factor of making track utilization change and analyzed appropriate estimated time. The railway's safety should be guaranteed by appropriate railway operating plan and by adequate rail facilities maintenance. At the same time, daily railway train 'Dia's recovery power should be reflected to the management plan. Considering these factors, we examined mechanical equipment and the national rail network in order to rationally estimate track repair time of the maintenance and to secure spare time in case of train delays. It was found that track utilization efficiency was more or less 60%.

• Nuclear Engineering and Technology
• /
• v.54 no.2
• /
• pp.501-506
• /
• 2022

Long turn-off time limits high frequency operation of Bipolar Junction Transistors (BJTs). Turn-off time decreases with increases in the recombination rate of minority carriers at switching transients. Fast neutron irradiation on a Si BJT incurs lattice damages owing to the displacement of silicon atoms. The lattice damages increase the recombination rate of injected holes with electrons, and decrease the hole lifetime in the base region of pnp Si BJT. Fast neutrons generated from a beryllium target with 30 MeV protons by an MC-50 cyclotron were irradiated onto pnp Si BJTs in experiment. The experimental results show that the turn-off time, including the storage time and fall time, decreases with increases in fast neutron fluence. Additionally, it is confirmed that the base current increases, and the collector current and base-to-collector current amplification ratio decrease due to fast neutron irradiation.

• Journal of Internet Computing and Services
• /
• v.6 no.2
• /
• pp.25-35
• /
• 2005

The Rate Monotonic(RM) scheduling algorithm and Earliest Deadline First(EDF) scheduling algorithm are normally used in Real-Time scheduling algorithm. In those scheduling algorithm, we could predict the performance possibility with total utilization value of task group. But. it had problems with prediction of the boundedness in individual task when the utilization value was over in temporary task. In this paper, the suggested scheduling algorithm can predict task when the utilization value was over and it suggested the method of predicting scheduling possibility based on the utilization value of individual task as well. it predicted the boundedness of scheduling possibility test through simulation In Real-Time scheduling algorithm and analyzed the result.