• International Journal of Quality Innovation
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• v.5 no.1
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• pp.110-121
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• 2004

There is a new trend of incorporating software coverage metrics into software reliability modelling. This paper proposes a coverage-based software reliability growth model. Firstly, the failure rate function in coverage is analytically derived. Then it is shown that the number of detected faults follows a Nonhomogeneous Poisson distribution of which intensity function is the failure rate function in coverage. Practical applicability of the proposed models is examined by illustrative numerical examples.

• Archives of Plastic Surgery
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• v.49 no.2
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• pp.215-220
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• 2022

Background In Japan, there is a large regional disparity in plastic surgery availability. In order for plastic surgery to be widely available for all citizens, it is essential for at least one plastic surgery facility to be located in each secondary medical zone. Methods Using the Japan Society of Plastic and Reconstructive Surgery homepage and some databases, we extracted data on secondary medical zones that do not have a plastic surgery facility. The national and regional coverage rates were calculated. The coverage rate for each group divided by the degree of population concentration was also calculated. Results We found that 147 of 344 secondary medical zones did not have a plastic surgery facility, and the area coverage rate was found to be 57.27% nationwide. The coverage rate in terms of population was 87.07% (correlation coefficient of area and population coverage = 0.983). The area coverage rates in Hokkaido-Tohoku, Kanto, Chubu, Kansai, Chugoku-Shikoku, and Kyushu-Okinawa districts were 47.46, 72.15, 76.47, 62.79, 52.08, and 32.81%, respectively. The corresponding population coverage rates were 79.92, 91.62, 94.27, 90.59, 80.68, and 69.54%, respectively. The area coverage rates in metropolitan areas, provincial cities, and rural areas were 98.08, 75.90, and 15.87%, respectively. In contrast, the area coverage rate of dermatology was 62.79% and that of orthopaedics was 97.09%. Conclusion Unfortunately, it is estimated that more than 40% of secondary medical zones are underserved by plastic surgery, and 13% of the population is not able to fully benefit from this specialty in Japan.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.18 no.1
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• pp.41-48
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• 2008

On the basis of total page, the coverage rate of education of safety and health in textbooks of elementary school was approximately 10%. In middle school, the contents of safety education were addressed mainly in subject of chemistry below about 5% of coverage rate whereas the contents of health education appeared mainly in subject of athletics below about 15% of coverage rate. Similarly, the contents of safety education and health education in textbooks of high school were indicated mainly in the subjects of chemistry and athletics, showing below about 5% and 30% of coverage rate, respectively. In conclusion, the education level of safety and health in textbooks was generally lower compared to other contents. The coverage rate of safety education was relatively lower than health education, which implicates that extensive contents related to safety education are needed to be added to textbooks in order to establish preliminary attitude for preventing workplace accident.

• Korean Management Science Review
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• v.14 no.1
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• pp.53-66
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• 1997

Generally, the standard sizes of military combat fatigues should be determined by considering the coverage rate in order to minimize the military personnel who can't put on the ready made military combat fatigues. The coverage rate should be increased by the longer interval of the standard size but the satisfactory rate will be decreased due to the longer interval of size. This study develops a method selecting optimal standard sizes of the military combat fatigues in order to maximize the satisfactory rate that insures the coverage rate to meet a given level for ready made military combat fatigues. This method selects candidate standard sizes at second and finally, establishes a 0-1 inter programming model. The result shows that the method increases both coverage and satisfactory rate more than those of the previous method.

• Journal of the Korean Operations Research and Management Science Society
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• v.14 no.1
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• pp.53-53
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• 1989

Generally, the standard sizes of military combat fatigues should be determined by considering the coverage rate in order to minimize the military personnel who can't put on the ready made military combat fatigues. The coverage rate should be increased by the longer interval of the standard size but the satisfactory rate will be decreased due to the longer interval of size. This study develops a method selecting optimal standard sizes of the military combat fatigues in order to maximize the satisfactory rate that insures the coverage rate to meet a given level for ready made military combat fatigues. This method selects candidate standard sizes at second and finally, establishes a 0-1 integer programming model. The result shows that the method increases both coverage and satisfactory rate more than those of the previous method.

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4329-4337
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• 2022

Jet impinging device is designed for decay heat removal on horizontal fuel rods in a low temperature heating reactor. An experimental system with a fuel rod simulator is established and experiments are performed to evaluate water film covering capacity, within 0.0287-0.0444 kg/ms mass flow rate, 0-164.1 kW/m² heating flux and 13.8-91.4℃ feeding water temperature. An effective method to obtain the film coverage rate by infrared equipment is proposed. Water film flowing patterns are recoded and the film coverage rates at different circumference angles are measured. It is found the film coverage rate decreases with heating flux during single-phase convection, while increases after onset of nucleate boiling. Besides, film coverage rate is found affected by Marangoni effect and film accelerating effect, and surface wetting is significantly facilitated by bubble behavior. Based on the observed phenomenon and physical mechanism, dry-out depth and initial dry-out rate are proposed to evaluate film covering potential on a heating surface. A model to predict film coverage rate is proposed based on the data. The findings would have reliable guide and important implications for further evaluation and design of decay heat removal system of new reactors, and could be helpful for passive containment cooling research.

• International Journal of Reliability and Applications
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• v.6 no.2
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• pp.87-99
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• 2005

Coverage-based software reliability growth models (SRGMs) have been developed and successfully applied in practice. Performance of a coverage-based SRG M depends on the coverage function employed by the SRGM. When the coverage function represents the coverage growth behavior well irrespective of type of the testing profile the corresponding coverage-based SRGM is expected to be widely applicable. This paper first conducts a study of selecting the most representative coverage functions among the available coverage functions. Then their performances are empirically evaluated and compared. The result provides a foundation for developing widely applicable coverage-based SRGMs and monitoring the progress of a testing process.

• Proceedings of the KSR Conference
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• 2000.05a
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• pp.330-335
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• 2000

Faults detection and containment requirements are typically allocated from a top-level specification as a percentage of total faults detection and containment, weighted by failure rate. This faults detection and containments are called as a fault coverage. The fault coverage requirements are typically allocated identically to all units in the system, without regard to complexity, cost of implementation or failure rate for each units. In this paper a simple methodology and mathematical model to support the allocation of system fault coverage rates to lower-level units by considering the inherent differences in reliability is presented. The models are formed as a form of constrained optimization. The objectives and constraints are modeled as a linear form and this problems are solved by linear programming. It is identified by simulation that the proposed solving methods for these problems are effective to such requirement allocating.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.1
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• pp.82-91
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• 2009

Research was initiated to investigate vegetation characteristics of native ('Pureundle' and 'Sewon') and introduced ('Brilliant' and 'Midnight') Kentucky bluegrass (KB, Poa pratensis L.) varieties by soil-seed applying system on a cut-slope in May 17, 2008. There were no statistic differences observed in soil hardness and soil moisture content while significant differences were observed in surface coverage rate, height and disease occurrence in native and introduced KB varieties. The introduced 'Brilliant' KB was highest in the surface coverage rate from the early period of seeding to August 11, 2008. The surface coverage rate of introduced varieties were high when compared to native varieties in their early growth stage. But native varieties reached to equal surface coverage rate with the introduced varieties when three months after seeding. The height of 'Pureundle' and 'Brilliant' KBs were high compared with Midnight and Sewon KBs. 'Pureundle' and 'Brilliant' KBs were damaged by disease whereas there were no disease occurrence in 'Midnight' and 'Sewon' KBs. Probably, the disease occurrence was close related with the height of KBs not with native and introduced KB varieties. These results indicate that the growth of KB on a cut-slope are statistically affected by varieties in early growth stage of this experiment but reach equal rate between native and introduced KB varieties in three months after seeding. This growth characteristics implies the huge potential of native KB varieties seeding for cut-slope vegetation. Considering that native KB varieties are adapted to a environment and have no risk of causing disturbance to the ecosystem compared to the introduced KB varieties, the use of them as native varieties for a cut-slope vegetation can be increased.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.3
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• pp.97-107
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• 2015

Research was initiated to investigate a vegetation characteristics of the species of ground cover plants mixed with herbeceous and woody plants on a cut slope. 4 different ground cover plants (Miscanthus sinensis var. purpurascens, Pennisetum alopecuroides, Festuca arundinacea and Zoysia japonica) were seeded at the same rate of $10.0g/m^2$ with herbaceous plants (Lotus corniculatus var. japonicus, Dianthus sinensis, Aster yomena, Chrysanthemum zawadskii and Coreopsis drummondii L) at the total seeding rate of $7.5g/m^2$ and native woody plants (Lespedeza bicolor Turcz, Indigofera pseudo-tinctoria and Albizzia julibrissin) at the total seeding rate of $7.5g/m^2$, respectively. This experiment was treated with 3 replications on a randomized block design. Data such as surface coverage rate(%), the germinating number, plant height and visual quality were analyzed. There were no statistic differences observed in the soil hardness and the soil moisture content while a significant difference was observed in the surface coverage rate and the germinating number. The surface coverage rate and the germinating number were significantly high in the Pennisetum alopecuroides plot when compared with the Miscanthus sinensis var. purpurascens plot, the Festuca arundinacea plot and the Zoysia japonica plot, respectively from the viewpoint of ground covers. Especially, the surface coverage rate was considerably low in the Festuca arundinacea plot. However, the surface coverage rate and the germinating number were no statistic differences observed in this treatment from the viewpoint of herbaceous and woody plants. Also, both of the plant height and visual quality were high in the Pennisetum alopecuroides plot when compared with the Miscanthus sinensis var. purpurascens plot, the Festuca arundinacea plot and the Zoysia japonica plot, respectively. We concluded that Pennisetum alopecuroides was the optimum plant from the treated ground covers mixed with native woody and herbaceous plants for the balanced emergence from the viewpoint of the ecological slope vegetation.