• Korean Journal of Ecology and Environment
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• v.52 no.4
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• pp.333-339
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• 2019

The Red swamp crawfish Procambarus clarkii is native to the southern United States and inhibits all over the world including the United States, Asia, Africa and Europe. In Europe, it is known to disrupt ecosystems such as competition with native crayfish. In this study, habitats of red swamp crawfish were identified in Jiseok stream (15.5 km section) and Daecho stream (6.1 km section) of Youngsan river. A total 33 red swamp crawfish were captured. A female captured in Jiseok stream carried 215 newly hatched red swamp crawfish in her the burrow. As a result of the analysis of the habitat environment, the water temperature was ranged of 2.4~32.8℃, conductivity was 53.4~502.3 μS cm^-1 and DO was 0.74~22.64 mg L^-1. As a result of measuring HOBO, the temperature ranged from -9~48.1℃, showing a change of 57.1℃ throughout the year. The variation of the water temperature throughout the year from 2.9~33.9℃ was found to be 31℃. Red swamp crawfish have a high adaptability and a wide range of environmental resistance, and report a sharp increase in newly invaded areas, negatively affecting indigenous organisms. In addition, it can be used as a medium for the spread of diseases and parasites, so prompt investigation and research should be carried out.

• Magazine of the Korea Concrete Institute
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• v.5 no.4
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• pp.167-178
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• 1993

The objective of this paper is to look into the possibility of the detailed and practical optimum design of rt:inforced concrete beam using methods oi discrete mathematical programming. In this discrete optimum formulation, the design variables are the overall depth, width and effective depth of members, and area of longitudinal reinforcement. In addition, the details such as the amount of web reinforcement and cutoff points of longitudinal reinforcement are also considered as variables. Total cost has been used as the objective function. The constraints include the code requirments such as flexural strength, shear strength, ductility, serviceability, concrete cover. spacing, web reinforcement, and development length and cutoff points of longitudinal renforcement. An optimization algorithm is presented for effective optimum design of R.C. beam with discrete de sign variables. First, the continuous variable optimization can be achieved by Feasible Direction Method. Using the results obtained from the continuous variable optimization, a branch and bound method is used to obtained the discrete design values. The proposed algorithm is applied to test problem for reliability, and the results are compared with those of graphical method and rounded-up method. And a simply supported R.C. beam and a two-span continuous R.C. beam are presented as numerical examples for effectiveness and applicability. It is considered that the presented algorithm can be effectively applied to the discrete optimum design of R.C. beams.

• Korean journal of applied entomology
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• v.56 no.3
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• pp.301-308
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• 2017

Locusts, Locusta migratoria (Orthoptera: Acrididae) are periodical unpredictable agricultural pests worldwide and cause serious damage to crop production; however, little consideration has been given to the management of this pest. Herein, we constructed a locust-pathogenic fungal library and confirmed that some fungi could be used as resources for locust management. First, the entomopathogenic fungi were collected from sampled soils using a Tenebrio molitor-based baiting system. For the locust assay, a locust colony was obtained from the National Institute of Agricultural Science and Technology. A total of 34 entomopathogenic fungal granules, which were produced by solid cultures, were placed in the plastic insect-rearing boxes (2 g/box) and nymphs of locust were contained in the box. In 3-7 days, mycosis was observed on the membranous cuticles of the head, abdomen, and legs of locusts. In particular, Metarhizium anisopliae, M. lepidiotae, and Clonostachys rogersoniana exhibited high virulence against the locust. Given that the 34 isolates could be used in field applications, their conidial production and stability (thermotolerance) were further characterized. In the thermotolerance assay, Paecilomyces and Purpureocillium isolates had higher thermotolerance than the other isolates. Most of the fungal isolates produced ca. >$1{\times}10^8conidia/g$ on millet grain medium. In a greenhouse trial, the granular application of M. anisopliae isolate on the soil surface resulted in 85.7% control efficacy. This work suggests that entomopathogenic fungi in a granular form can be effectively used to control the migratory locust.

• Tuberculosis and Respiratory Diseases
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• v.43 no.5
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• pp.693-700
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• 1996

Background : Antituberculous therapy is set a short-term therpy used isoniazid(INH), rifampin(RFP), ethambutol(EMB), pyrazinamide(PZA) from 1970s' and treatment rate has been very improved. But drug interruption or irregular medication due to side effects and resistance of drug are serious problem to retreatment cases, specially. Ofloxasine(OFX), developed from Quinolone at 1980's is effective not only other respiratory infectious disease but also pulmonary tube rculosis. And this is useful drug instead of injection agents for retreatment patients who have side effects to other drugs, lived far distance from medical clinics. So, we will evaluate theffectiveness as four oral drugs involving OFX. Method : A retrospective study was made through the regular follow up of smear positive cases,who treated by four drug, namely, prothionamide (PTA) cycloserine(CS), OFX, paraminosalicylic acid(pAS). Results: 1) Out of 66case with positive sputum AFB smear, 42(64%)cases achieved the negative conversion. 2) Considering the negative conversion in all group, 34 case (52%) of sputum conversion occured within first 6 months, on the extent of diease was minimal, moderate, far advanced pulmonary tuberculosis, sputum AFB smear negative response to treatment was 100%, 78%, 46% respectively. 3) The roentgenological improvement occured in 38(58%), extent of diease was minimal, moderately, far advanced pulmonary tuberculosis, Roentgenological improvement to retreatment was 75%, 64%, 46%. 4) When the drnation of patients illness was less than 1 year, 1 to 3 years, 3 10 5 years and more than 5 years, sputum AFB smear negative response to retreatment was 100%, 88%, 80%, 52 %. 5) On side effects, major problems are gastrointestinal troubles, mild liver function abnormality, psychotic problemes, and skin problem(urticaria, itching sensation). Conclusion : The duration & extents of patients illness was shorter & minimal, sputum AFB smear negative response rate was better. Radiologic response is better as shorter duration and minimal extent of diease. But, as diease is longer duration & far advanced, sputum negative conversion & Roentgenological improvement is poor and limited. The adverse reaction was mainly observed gastrointestinal troubles(indigestion, abdominal pain, nausea, vomiting, diarrhea) and are well controled by symptomatic management in most patients, as regard to tolerance to the secondary drugs.