• Title/Summary/Keyword: sine function

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Temperature-dependent Development of Pseudococcus comstocki(Homoptera: Pseudococcidae) and Its Stage Transition Models (가루깍지벌레(Pseudococcus comstocki Kuwana)의 온도별 발육기간 및 발육단계 전이 모형)

  • 전흥용;김동순;조명래;장영덕;임명순
    • Korean journal of applied entomology
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    • v.42 no.1
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    • pp.43-51
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    • 2003
  • This study was carried out to develop the forecasting model of Pseudococcus comtocki Kuwana for timing spray. Field phonology and temperature-dependent development of p. comstocki were studied, and its stage transition models were developed. p comstocki occurred three generations a year in Suwon. The 1 st adults occurred during mid to late June, and the 2nd adults were abundant during mid to late August. The 3rd adults were observed after late October. The development times of each instar of p. comstocki decreased with increasing temperature up to 25$^{\circ}C$, and thereafter the development times increased. The estimated low-threshold temperatures were 14.5, 8.4, 10.2, 11.8, and 10.1$^{\circ}C$ for eggs, 1st+2nd nymphs, 3rd nymphs, preoviposition, and 1st nymphs to preoviposition, respectively. The degree-days (thermal constants) for completion of each instar development were 105 DD for egg,315 DD for 1st+2nd nymph, 143 DD for 3rd nymph, 143 DD for preoviposition, and 599 DD for 1 st nymph to preoviposition. The stage transition models of p. comstocki, which simulate the proportion of individuals shifted from a stage to the next stage, were constructed using the modified Sharpe and DeMichele model and the Weibull function. In field validation, degree-day models using mean-minus-base, sine wave, and rectangle method showed 2-3d, 1-7d, and 0-6 d deviation with actual data in predicting the peak oviposition time of the 1st and 2nd generation adults, respectively. The rate summation model, in which daily development rates estimated by biophysical model of Sharpe and DeMichele were accumulated, showed 1-2 d deviation with actual data at the same phonology predictions.

Strategies for Public Health Service Development in the Times of Local Autonomy (지방자치시대의 공공보건사업 발전 전략)

  • 박정한
    • Health Policy and Management
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    • v.12 no.3
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    • pp.1-22
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    • 2002
  • Health is a fundamental human right and a sine qua non for happiness of people and for national development. Government has a responsibility for the provision of health services for their people. Recent changes of disease pattern, i.e. decrease of Infectious diseases and increase of chronic and degenerative diseases Including cancer and cardiovascular diseases, together with universal coverage of health insurance and improved living standard have prompted medical care utilization and skyrocketed the national health expenses. The goal of national health policy is improving the quality of life through the betterment of health level. To achieve this goal it is necessary to establish a healthcare system for lifetime, to improve the efficiency of healthcare delivery system, and to strengthen the public health services for disease prevention and health promotion. The current public health service programs are Inefficient due to an inconsistent policy for health service program, lack of health information system, irrational health program planning and evaluation, and Inadequate training of health workers. Local government has a legal responsibility for health service program planning and promoting the competence of health workers. Thus, municipal and provincial health departments should expand their roles and strengthen their function. The strategies for developing public health service programs at local level are ${\circled}1$ stipulating the goals of health policy, ${\circled}2$ promoting the ability for health program planning and evaluation, ${\circled}3$ establishing health information and surveillance system, ${\circled}4$ training of health workers, ${\circled}5$ establishing an institution for health information management and training of health workers, and ${\circled}61$ collaboration with local universities.