• Journal of applied mathematics & informatics
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• v.27 no.3_4
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• pp.779-793
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• 2009

This paper deals with a delayed SEIRS epidemic model with pulse vaccination and crowded incidence rate. Moreover, the case of vertical and horizontal transmission is considered. By using the discrete dynamical system determined by the stroboscopic map, the exact infection-free periodic solution of the SEIRS model is obtained. Further, by employing the comparison arguments, we prove that under the condition that $R_*$ < 1 the infection-free periodic solution is globally attractive, and that under the condition that $R^*$ > 1 the disease is uniformly persistent, which means that after some period of time the disease will become endemic.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.18 no.4
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• pp.317-335
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• 2014

In this work, we investigate the global stability analysis of a viral infection model with antibody immune response. The incidence rate is given by a general function of the populations of the uninfected target cells, infected cells and free viruses. The model has been incorporated with two types of intracellular distributed time delays to describe the time required for viral contacting an uninfected cell and releasing new infectious viruses. We have established a set of conditions on the general incidence rate function and determined two threshold parameters $R_0$ (the basic infection reproduction number) and $R_1$ (the antibody immune response activation number) which are sufficient to determine the global dynamics of the model. The global asymptotic stability of the equilibria of the model has been proven by using Lyapunov theory and applying LaSalle's invariance principle.

• Electrical & Electronic Materials
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• v.8 no.2
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• pp.129-135
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• 1995

SiO thin films are deposited by evaporator the refractive index of wave length, photon energy and the absorptive rate of these films are measured by spectroscopic ellipsometer. It is derived the absorptive rate and permitivity of SiO thin films from the equations that calculating the refractive index. And the result show good agreement with the calculated values and experimental values. As a result, the wave length of light is increased in the condition that the angle of incidence is fixed on SiO thin film, the basic absorption and the absorption impurities are found in the low wave length (below 450 nm in this study) and the reflective absorption and conductive absorption is increased by the form of exponential function over the low wavelength. The absorptive rate is increased by increased the angle of incidence and thickness of SiO film for the insulating layer. As the thickness of SiO film is increased, the value of complex permitivity is decreasing and as wave length of incidence is increased., the value of dielectric is linearly increasing.

• Journal of Veterinary Clinics
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• v.14 no.2
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• pp.141-146
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• 1997

This study was performed to investigate the ophthalmic diseases in 269 Holstein dairy cattle of 10 farms in Kyunggido, Korea. The acerage prevalence rate of ophthalmec diseases was 25.7%, ranging of from 4.8% to 47.6%. The highest incidence age was between 3 and 4 years old, 41.9% and then in order of between 5 and 6 years, between 2 and 3 years, over 6 years, between 4 and 5 years, between 1 and 2 years, and up to 1 year were shown the incidence of 33.3%, 29.4%, 27.7%, 23.8%, 19.8% and 12.5%, respectively. The prevalence rate of cataracts was higher than any other ophthalmic diseases, 10.4% and then in order of chorioretinitis, iris posterior synechiae, corneal scar, conjunctivitis, blindness, third eyelid carcinoma and globe anomaly were diagnosed as the incidence of 4.1%, 3.0%, 1.7%, 1.3%, 0.4%, 0.2% and 0.2%, respectively.

• International Journal of Reliability and Applications
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• v.2 no.4
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• pp.263-268
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• 2001

Shanmugam(1991) generalized the Poisson distribution to capture a restriction on the incidence rate $\theta$ (i.e. $\theta$ ＜ $\beta$, an unknown upper limit), and named it incidence rate restricted Poisson (IRRP) distribution. Using Neyman's C($\alpha$) concept, Shanmugam then devised a hypothesis testing procedure for $\beta$ when $\theta$ remains unknown nuisance parameter. Shanmugam's C ($\alpha$) based .results involve inverse moments which are not easy tools, This article presents an alternate testing procedure based on likelihood ratio concept. It turns out that likelihood ratio test statistic offers more power than the C($\alpha$) test statistic. Numerical examples are included.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2171-2175
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• 2016

Trends in cancer incidence is a key tool to identify the pattern of cancer of any country. This retrospective study was performed to present the trends of change in cancer incidence in Nepal.The total number of cancer cases in males was 26,064 while the total number of females cancer cases was 29,867 throughout the 10 years from 2003 to 2012. The cancer incidence per 100,000 in males was 12.8 in 2003 and 25.8 people in 2012. Similarly, in females, the crude incidence rate was 15.1 in 2003 and 26.7 per 100,000 in 2012. Cancer incidence was low at early age but it was increased with age in both sexes in Nepal. Lung cancer was the most common cancer in males throughout, while it was the third most common cancer in females. Cervix uteri was the most common site of cancer in females throughout the 10 years, with a clear trend for increase in breast cancer within this time.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.5
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• pp.615-622
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• 2000

Numerical simulation is performed with Denton's code to get pressure loss coefficients in wide range of reverse flow incidence(from -90 degree to +85 degree) for an axial compressor cascade. As a results, it is found that the pressure loss coefficient is increased with incidence and there exist critical incidence which corresponds to the maximum pressure loss coefficient. Pressure loss coefficient with bigger incidence than its critical value is decreased. The effect of increasing incidence in a cascade extremely reduce the mass flow rate by the large flow separation region. Consequently this effect reduce the portion of dynamic pressure in the total pressure loss and beyond the critical incidence the pressure loss coefficient decrease.

• Journal of Preventive Medicine and Public Health
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• v.28 no.3 s.51
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• pp.551-562
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• 1995

To assess the status of safety accidents, authors reviewed and analysed the records of safety accidents of a welding material manufacturing factory at Pohang city from January 1989 to December 1993. The results are; 1. The total incidence of safety accidents was 295 spells for five years. 2. Average age of workers with accident was 35.7 years. Average duration of employment was 6.2 years and the duration of employment increased as the year increased. 3. There was no statistical significance on season, month, weekday and time by year in the incidence of safety accidents. The most frequent part of body injured was upper extremities and the most frequent type of injury was abrasion. 4. Mean admission rate of safety accidents was 12.6% and the ratio of treated spells as occupational injury was 7.8%. 5. The most frequent cause of injury was worker's mistake and the most frequent action for the prevention of further accidents was safety education. 6. The incidence rate of safety accidents on 1993 was 116.2 spells per 1,000 persons. Above results suggest that to prevent safety accidents, safety education should be done continuously, the environmental and human factors were controlled and more exact reporting system of safety accidents was needed.

• Korean Journal of Adult Nursing
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• v.15 no.3
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• pp.463-471
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• 2003

Purpose: This study was aimed at providing scientific evidence for minimizing ventilator-associated pneumonia(VAP) by identifying appropriate timing of exchange of circuit for mechanical ventilator that is well suitable for the medical environment of intensive care units of hospitals in Korea. Method: This was a quasi-experimental study with a convenience sample of 19 adult subjects aged over 18 years who were admitted to the NS ICU of C university hospital, and placed on mechanical ventilator. The subjects were placed in two groups, compared on the incidence rate of VAP after they received exchange of circuit either at 1-week interval (N =10) or 2-week interval (N = 9). Result: 1) When considering 1000 days as the standard unit of analysis for incidence, the incidence rate of VAP was 7.19 cases at the 1-week cycle exchange group and 15.23 at the 2-week cycle exchange group, showing no statistically significant difference between the two groups. 2) There were a total of 3 types of bacteria isolated from the patients with VAP, including 2 cases with P. aeruginosa, 1 case with Streptococcus group F and A. baumannii. Conclusion: With thorough hand washing and strict management of tracheal tube of mechanical ventilator as well as use of tracheal intubation techniques, exchange cycle of circuit of mechanical ventilator by nurses may be changed from 1-week to 2-week interval.

• Journal of Korean Biological Nursing Science
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• v.18 no.2
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• pp.110-117
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• 2016

Purpose: This study was conducted to compare the incidence rate of influenza-like illnesses between an influenza-vaccinated group and a non-vaccinated group of adults. Methods: From July 1, 2015 to July 30, 2015, self-reporting questionnaires were given to 300 adults living in the Seoul and Gyeonggi-do, Korea. 265 survey questionnaires that had an earnest response were used for data analysis. The collected data were analyzed using the statistical software SPSS Win 18.0 version. Results: 52.1% of the participants were vaccinated. The incidence rate of influenza-like illnesses was 11.3%. Within the influenza-vaccinated group, 12.3% experienced an influenza-like illness. On the other hand, in the non-vaccinated group, 10.2% experienced an influenza-like illness. There was no statistically significant difference in the incidence of influenza-like illness depending on vaccination status. Conclusion: During the influenza season from Fall 2014 to Spring 2015, there was no significant difference on the prevalence of influenza-like illness between the study participants whether they were vaccinated or not. Thus, future studies should confirm and closely examine this fact, whether it was a matter of pandemic strain selection or whether there were differences in the effects of adult influenza vaccination as reported in previous studies.