• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1905-1919
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• 2000

The main motivation of this research is to develop an intelligent control strategy for Activated Sludge Process (ASP). ASP is a complex and nonlinear dynamic system because of the characteristic of wastewater, the change in influent flow rate, weather conditions, and etc. The mathematical model of ASP also includes uncertainties which are ignored or not considered by process engineer or controller designer. The ASP is generally controlled by a PID controller that consists of fixed proportional, integral, and derivative gain values. The PID gains are adjusted by the expert who has much experience in the ASP. The ASP model based on $Matlab^{(R)}5.3/Simulink^{(R)}3.0$ is developed in this paper. The performance of the model is tested by IWA(International Water Association) and COST(European Cooperation in the field of Scientific and Technical Research) data that include steady-state results during 14 days. The advantage of the developed model is that the user can easily modify or change the controller by the help of the graphical user interface. The ASP model as a typical nonlinear system can be used to simulate and test the proposed controller for an educational purpose. Various control methods are applied to the ASP model and the control results are compared to apply the proposed intelligent control strategy to a real ASP. Three control methods are designed and tested: conventional PID controller, fuzzy logic control approach to modify setpoints, and fuzzy-PID control method. The proposed setpoints changer based on the fuzzy logic shows a better performance and robustness under disturbances. The objective function can be defined and included in the proposed control strategy to improve the effluent water quality and to reduce the operating cost in a real ASP.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.207-220
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• 2012

There are around 7,500 manure tanks to treat the manures from pigs in Korea. In the tank, there are too much sediments deposited on the base and wall, which causes low efficiency of stock capacity and manure fermentation. In order to minimize sediments and to ferment manure effectively, we developed a 2-fluid jet mixer for mixing sediments in liquid livestock manure tank. For developing the prototype, we tested a factorial experimental system with various nozzles, and simulated CFD models with two kinds of nozzle arrangement. From the results of factorial experiment and CFD simulation, we concluded the dia. ratio of primary : secondary nozzle should be 1:2 and the nozzles should be arranged at the same distances toward to the circumferential direction. With this results, we manufactured a 2-fluid jet mixer which is consists of four 2-phase nozzles, centrifugal slurry pump and root's type air blower. And, we carried out the performance test of the prototype in the round shaped liquid manure tank in the farm. The performance test results showed that the uniformity of TS (Total Solid) and VS (Volatile Solid) was raised from 21.3 g/L, 13.3 g/L In steady state to TS and VS to 23.0 g/L, 14.1 g/L in the mixing operation. Therefore, we could conclude that the prototype of 2-fluid mixer could make the solid material which could be sediments in the tank not to be deposited in the tank and to be contacted to air bubbles which could enhance the efficiency of the fermentation of livestock manure.

• Journal of Korea Water Resources Association
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• v.53 no.1
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• pp.15-27
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• 2020

Streamflow discharge as a fundamental riverine quantity plays a crucial role in water resources management, thereby requiring accurate in-situ measurement. Recent advances in instrumentations for the streamflow discharge measurement has complemented or substituted classical devices and methods. Among various potential methods, surface current meter using microwave has increasingly begun to be applied not only for flood but also normal flow discharge measurement, remotely and safely enabling practitioners to measure flow velocity postulating indirect contact. With minimized field preparedness, this method facilitated and eased flood discharge measurement in the difficult in-situ conditions such as extreme flood in active ways emitting 24.125 GHz microwave without relying on natural lights. In South Korea, a rectangular shaped instrument named with Microwave Water Surface Current Meter (MWSCM) has been developed and commercially released around 2010, in which domestic agencies charging on streamflow observation shed lights on this approach regarding it as a potential substitute. Considering this brand-new device highlighted for efficient flow measurement, however, there has been few noticeable efforts in systematic and comprehensive evaluation of its performance in various measurement and riverine conditions that lead to lack in imminent and widely spreading usages in practices. This study attempted to evaluate the MWSCM in terms of instrumen's monitoring configuration particularly regarding tilt and yaw angle. In the middle of pointing the measurement spot in a given cross-section, the observation campaign inevitably poses accuracy issues related with different tilt and yaw angles of the instrument, which can be a conventionally major source of errors for this type of instrument. Focusing on the perspective of instrument configuration, the instrument was tested in a controlled outdoor river channel located in KICT River Experiment Center with a fixed flow condition of around 1 m/s flow speed with steady flow supply, 6 m of channel width, and less than 1 m of shallow flow depth, where the detailed velocity measurements with SonTek micro-ADV was used for validation. As results, less than 15 degree in tilting angle generated much higher deviation, and higher yawing angle proportionally increased coefficient of variance. Yaw angles affected accuracy in terms of measurement area.

• Korean Security Journal
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• no.14
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• pp.367-388
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• 2007

Some of individuals working at various fields of security guard are given the legal right to use a gun to cope with expected risks and crimes. Not only in Korea but also throughout the world, a pistol is being used as a device for the workers of security guard such as the army, the police and intelligence agencies to keep the law and social order. A pistol, which is regarded as the last safety measure of security guard, is easy to carry but, because of its short barrel for high portability, its hit ratio and long-range shooting performance are much lower than ordinary guns. Despite such weak points, a pistol can be a great tool because of its high portability and if the users make steady efforts to improve their skills and, for this reason, it has been being used widely until now. National agency workers' pistol shooting skills depend on several important factors, but for the fast and accurate shooting, the mot important factor is how to aim at the target. Because it takes a relatively longer time to align the sight on the target, the change of the sight alignment method is expected to improve pistol shooting skills a lot. In Korea, however, most of national agency training centers teach the basic aiming method that crosses the foresight and the backsight and aligns the crossing to the target. That is, they teach the sight alignment method for fixed targets. Some agencies in Korea and foreign countries that have used guns more frequently and longer than us are teaching different sight alignment methods as well. Representative ones of them are aiming only with the foresight and pointing shooting. These aiming methods are expected to produce good results against moving targets. While the basic sight alignment method has to cross the foresight and the backsight and then to align the crossing to the target, so takes a longer time than other aiming methods, the other two aiming methods are expected to be effective in fields where both swiftness and accuracy are require. Because domestic agencies are teaching mainly the basic sight alignment method, the present study purposed to examine the effects of different aiming methods on shooting records and ultimately to contribute to national agency workers' operation. For this purpose, we selected 20 policemen from local police commandos under the National Police Agency who were accustomed to pistol shooting and measured their pistol shooting. According to the results, the pointed shooting method showed the best record in 5m short.range shooting. As to hit ratio in 15m shooting, which is relatively long.range for pistol shooting, the basic aiming method showed the best record, but the results of statistical analysis showed that pointed shooting is most superior. Of course, the results were obtained from a group who were used to and skillful in pistol shooting, but they are considered meaningful in that all the police and national agency workers should have such high shooting skills.

• Journal of Veterinary Clinics
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• v.23 no.2
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• pp.114-118
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• 2006

A study on bioavailability and pharmacokinetics of florfenicol was conducted in broilers following a single intravenous (i.v.) and oral (p.o.) doses of 20 mg/kg body weight (b.w.). Florfenicol concentrations in plasma were determined by a high-performance liquid chromatography/mass spectrometry. Plasma concentration-time data after i.v. administration were analyzed by a non-compartmental analysis. Following i.v. injection, the total body clearance was $0.74{\pm}0.25L/kg/h$ and the volume of distribution at steady-state was $1.16{\pm}0.19L/kg$. Florfenicol was rapidly distributed and eliminated following i.v. injection with $1.15{\pm}1.06h$ of elimination half-life. After oral administration, the calculated $C_{max}$ values ($8.18{\pm}0.97{\mu}g/mL$) were reached at $1.33{\pm}0.29h$ in broilers. The elimination half-life of florfenicol was $1.31{\pm}0.27h$ and the absolute bioavailability (F) was 75.46% after oral administration of florfenicol. Florfenicol amine, a major metabolite of florfenicol, was detected in all broilers after i.v. and p.o. administration of florfenicol. The observed $C_{max}$ values of florfenicol amine ($3.96{\pm}2.60\;and\;2.22{\pm}1.71{\mu}g/mL$) were reached at $0.16{\pm}0.19\;and\;1.61{\pm}1.02h$ after i.v. and p.o. administration of florfenicol, respectively. Florfenicol amine was eliminated with $1.88{\pm}0.39\;and\;2.64{\pm}1.39h$ of the elimination half-life after i.v. and p.o. administration of florfenicol, respectively.

• Research in Plant Disease
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• v.8 no.2
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• pp.84-91
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• 2002

Disease forecasting in Korea was first studied in the Department of Fundamental Research, in the Central Agricultural Technology Institute in Suwon in 1947, where the dispersal of air-borne conidia of blast and brown spot pathogens in rice was examined. Disease forecasting system in Korea is operated based on information obtained from 200 main forecasting plots scattered around country (rice 150, economic crops 50) and 1,403 supplementary observational plots (rice 1,050, others 353) maintained by Korean government. Total number of target crops and diseases in both forecasting plots amount to 30 crops and 104 diseases. Disease development in the forecasting plots is examined by two extension agents specialized in disease forecasting, working in the national Agricul-tural Technology Service Center(ATSC) founded in each city and prefecture. The data obtained by the extension agents are transferred to a central organization, Rural Development Administration (RDA) through an internet-web system for analysis in a nation-wide forecasting program, and forwarded far the Central Forecasting Council consisted of 12 members from administration, university, research institution, meteorology station, and mass media to discuss present situation of disease development and subsequent progress. The council issues a forecasting information message, as a result of analysis, that is announced in public via mass media to 245 agencies including ATSC, who informs to local administration, the related agencies and farmers for implementation of disease control activity. However, in future successful performance of plant disease forecasting system is thought to be securing of excellent extension agents specialized in disease forecasting, elevation of their forecasting ability through continuous trainings, and furnishing of prominent forecasting equipments. Researches in plant disease forecasting in Korea have been concentrated on rice blast, where much information is available, but are substan-tially limited in other diseases. Most of the forecasting researches failed to achieve the continuity of researches on specialized topic, ignoring steady improvement towards practical use. Since disease forecasting loses its value without practicality, more efforts are needed to improve the practicality of the forecasting method in both spatial and temporal aspects. Since significance of disease forecasting is directly related to economic profit, further fore-casting researches should be planned and propelled in relation to fungicide spray scheduling or decision-making of control activities.

• Tuberculosis and Respiratory Diseases
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• v.52 no.2
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• pp.128-136
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• 2002

Background: There are few studies that have reported on the pharmacokinetic(PK) disposition of fluoroquinolones in patients with multi-drug resistant tuberculosis(MDR-Tb), even though fluoroquinolones are frequently co-prescribed to those patients. In this study, the PK disposition of ofloxacin, a fluoroquinolone, was evaluated in patients with MD R -Tb. Methods: Twenty patients with MDR-Tb were given 2nd line Tb drugs including ofloxacin (300mg twice a day), prothionamide, cycloserine, para-aminosalicylic acid, kanamycin, and streptomycin. The patients were grouped according to their body mass index(BMI) as an index of emaciation (group A : 18.5$\leq$BMI <23, group B : BMI < 18.5). Blood samples were serially drawn and urine samples were collected upto 24 hours after the last dose of those drugs at steady state (over 1 month). The ofloxacin concentrations were determined using HPLC (High Performance Liquid Chromatography). Results: The AUC of ofloxacin in group B was greater than that in group A ($31.4{\pm}8.9{\mu}g/ml{\cdot}h$ vs. $24.1{\pm}6.2{\mu}g/ml{\cdot}h$)(Check the symbols), (p<0.05). The total clearance(Cl/F) of ofloxacin was $0.16{\pm}0.03$ L/h/kg in group A, and $0.14{\pm}0.03$ L/h/kg in group B. The half-lives of ofloxacin in two groups were similar (group A : $5.3{\pm}0.8$ hours, group B : $5.7{\pm}0.9$ hours). In addition, the other PK parameters in two groups were also similar. Conclusions: The pharmacokinetics of ofloxacin in patients with MDR-Tb appears to be comparable with those of normal subjects, and the extent of emaciation appears to have an influence on the pharmacokinetics of ofloxaicn in chronic debilitated MDR-Tb patients.

• Knowledge Management Research
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• v.22 no.3
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• pp.217-233
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• 2021

Small business owners are currently greatly affected by the economic downturn caused by COVID-19. It is a study on the expected effect of education on management education of small business owners and the sustainability of the project on the premise that education can increase the self-sustainability of small business owners amid the rapidly changing global economy and consumer sentiment due to COVID-19. The following research results were derived by surveying those who completed management education of the Small Business Market Promotion Foundation. Management education was found to have a positive effect on education expectation effect, and education expectation effect was also found to have a positive effect on sustainability. In addition, management education had a positive effect on the sustainability of the project, and the expected effect of education was mediated between management education and sustainability. These results show that management education has a positive effect on survival and continuous performance in the business of small business owners, and steady efforts to acquire education can be said to be helpful in management activities. As a practical implication, first, since positive education expectations for management education can be seen as affecting the sustainability of the project, it should be possible to increase the expected effect by configuring interest and interest in education when forming management education programs. Second, management education directly affects the maintenance, survival, and sustainability of small business owners, and the knowledge acquired by participating in education helps improve management activities, so you can think of adding the amount and number of educational support. Third, since the sustainability of small business owners also affects the survival of the business, more active promotion of education will be needed so that more small business owners can receive management education.

• The Southeast Asian review
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• v.27 no.1
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• pp.95-129
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• 2017

This study surveys and reviews political change, economic performance, and regional cooperation that were carried out in 2016 by Southeast Asian countries and ASEAN. This paper reports that what has followed the inauguration of new governments in Myanmar, the Philippines, Vietnam, and Laos fails to live up to the expectation and optimism that arose in the aftermath of elections and party congresses that took place in the first half of the year. In other countries such as Malaysia, Thailand, and Cambodia, where authoritarian regimes are faced with strong oppositions, the prospects for democratic change worsened to a substantial degree, as schisms and internal strives complicated the opposition camp as a result of instigation and intervention by the authoritarian leaders and their followers. In stable political systems, both democratic and authoritarian, no significant changes that may entail serious political implications were noticed. In 2016, the national economy of almost each and every country continued its slow but steady recovery that had started in 2014 and grew by 5% on the average. For 2017 onward, however, the earlier optimism that it would grow at least as fast dimmed down as uncertainty about the world economy looms larger due to the unexpected win by Donald Trump as U.S. president and the expected 'hard landing' of the Chinese economy around 2018. ASEAN declared the launch of the ASEAN Economic Community (AEC) only one day before the New Year, but its track record looked already bad and unpromising by the end of 2016. ASEAN leaders were tied up by their domestic politics and affairs too tightly to take time off to work seriously to observe the schedule as laid out in the AEC Blueprint 2025. Korea's relationship with Southeast Asian countries and ASEAN was "as good as it gets" in 2016 as ever but could become subject to tough review in the near future, if the Ministry of Foreign Affairs is found out to have been implicated in the ongoing Choi Sun Sil scandal and if the opposition wins the next presidential election to be held by this year.

• Journal of agricultural medicine and community health
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• v.1 no.1
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• pp.5-9
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• 1976

The categories of national health problems may be mainly divided into health promotion, problems of diseases, and population-economic problems which are indirectly related to health. Of them, the problems of diseases will be exclusively dealt with this speech. Rurality and Disease Problems There are many differences between rural and urban areas. In general, indicators of rurality are small size of towns, dispersion of the population, remoteness from urban centers, inadequacy of public transportation, poor communication, inadequate sanitation, poor housing, poverty, little education lack of health personnels and facilities, and in-accessibility to health services. The influence of such conditions creates, directly or indirectly, many problems of diseases in the rural areas. Those art the occurrence of preventable diseases, deterioration and prolongation of illness due to loss of chance to get early treatment, decreased or prolonged labour force loss, unnecessary death, doubling of medical cost, and economic loss. Some Considerations of Innovative Approach The followings art some considerations of innovative approaches to the problems of diseases in the rural Korea. 1. It would be essential goal of the innovative approaches that the damage and economic loss due to diseases will be maintained to minimum level by minimizing the absolute amount of the diseases, and by moderating the fee for medical cares. The goal of the minimization of the disease amount may be achieved by preventive services and early treatment, and the goal of moderating the medical fee may be achieved by lowering the prime cost and by adjusting the medical fees to reasonable level. 2. Community health service or community medicine will be adopted as a innovative means to disease problems. In this case, a community is defined as an unit area where supply and utilization of primary service activities can be accomplished within a day. The essential nature o the community health service should be such activities as health promotion, preventive measures, medical care, and rehabilitation performing efficiently through the organized efforts of the residents in a community. Each service activity should cover all members of the residents in a community in its plan and performance. The cooperation of the community peoples in one of the essential elements for success of the service program, The motivations of their cooperative mood may be activated through several ways: when the participation of the residents in service program of especially the direct participation of organized cooperation of the area leaders art achieved through a means of health education: when the residents get actual experience of having received the benefit of good quality services; and when the health personnels being armed with an idealism that they art working in the areas to help health problems of the residents, maintain good human relationships with them. For the success of a community health service program, a personnel who is in charge of leadership and has an able, a sincere and a steady characters seems to be required in a community. The government should lead and support the community health service programs of the nation under the basis of results appeared in the demonstrative programs so as to be carried out the programs efficiently. Moss of the health problems may be treated properly in the community levels through suitable community health service programs but there might be some problems which art beyond their abilities to be dealt with. To solve such problems each community health service program should be under the referral systems which are connected with health centers, hospitals, and so forth. 3. An approach should be intensively groped to have a physician in each community. The shortage of physicians in rural areas is world-wide problem and so is the Korean situation. In the past the government has initiated a system of area-limited physician, coercion, and a small scale of scholarship program with unsatisfactory results. But there might be ways of achieving the goal by intervice, broadened, and continuous approaches. There will be several ways of approach to motivate the physicians to be settled in a rural community. They are, for examples, to expos the students to the community health service programs during training, to be run community health service programs by every health or medical schools and other main medical facilities, communication activities and advertisement, desire of community peoples to invite a physician, scholarship program, payment of satisfactory level, fulfilment of military obligation in case of a future draft, economic growth and development of rural communities, sufficiency of health and medical facilities, provision of proper medical care system, coercion, and so forth. And, hopefully, more useful reference data on the motivations may be available when a survey be conducted to the physicians who are presently engaging in the rural community levels. 4. In communities where the availability of a physician is difficult, a trial to use physician extenders, under certain conditions, may be considered. The reason is that it would be beneficial for the health of the residents to give them the remedies of primary medical care through the extenders rather than to leave their medical problems out of management. The followings are the conditions to be considered when the physician extenders are used: their positions will be prescribed as a temporary one instead of permanent one so as to allow easy replacement of the position with a physician applicant; the extender will be under periodic direction and supervision of a physician, and also referral channel will be provided: legal constraints will be placed upon the extenders primary care practice, and the physician extenders will used only under the public medical care system. 5. For the balanced health care delivery, a greater investment to the rural areas is needed to compensate weak points of a rurality. The characteristics of a rurality has been already mentioned. The objective of balanced service for rural communities to level up that of urban areas will be hard to achieve without greater efforts and supports. For example, rural communities need mobile powers more than urban areas, communication network is extremely necessary at health delivery facilities in rural areas as well as the need of urban areas, health and medical facilities in rural areas should be provided more substantially than those of urban areas to minimize, in a sense, the amount of patient consultation and request of laboratory specimens through referral system of which procedures are more troublesome in rural areas, and more intensive control measures against communicable diseases are needed in rural areas where greater numbers of cases are occurred under the poor sanitary conditions.