• Journal of the Korean Data and Information Science Society
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• v.27 no.3
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• pp.599-607
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• 2016

The first patient of Middle East respiratory syndrome caused by a novel coronavirus infection in Korea was confirmed on May 20, 2015. After that, MERS spread over the country. In recent years, patients of MERS have been found around the Arabian Peninsula and the case fatality ratio of MERS in those area was been reported to range from 30 to 40%. In this paper, we estimate the case fatality ratio of MERS of Korea using data of 186 infections until December 1, 2015. In this study we propose a novel estimator of the case fatality ratio using information of the patients severity condition as well as records on the days of confirmation and death or recovery of the patient. By using publicly available data of the Department of Health and Human Services Centers for Disease Control, we evaluate a performance of the estimator and demonstrate a stability of the estimator from the early stage of the epidemic.

• The Journal of Natural Sciences
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• v.9 no.1
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• pp.45-52
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• 1997

We have examined the effects of low concentrations of MNNG, alkylating agent, in survival and mutagenesis in Aspergillus nidulans. Pretreatments of cells with nontoxic and submutagenic doses of MNNG did not reduce the cytotoxic and mutagenic effects of exposure to a high concentration of drug. The results imply that adaptive responses on survival and mutagenesis for MNNG treatments do not occur in Aspergillus nidulans. In the first mitotic cell cycle during germination, the sensitivity to MNNG has been investigated at hourly time interval, and compared with that for UV irradiation. In both UV and MNNG treatments, the sensitivity increased till S cell stage, and decreased while DNA replication continued. Different from that show for UV irradiation, lethality to MNNG reached to the maximum at G2 cell stage.

• The Korean Journal of Zoology
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• v.8 no.2
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• pp.80-84
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• 1965

본 실험은 몇 가지 해산 무척추동물, Crassostrea gigas (THUNBERG) , Musculus senhousia (BENSON), Adula atrata(LISCHKE), Littorina brevicula (PHILIPPI) 그리고 BALANUS amphitrite communis (DARWIN) 의 치사율에 대한 온도의 영향을 밝히고저 실시한 것이다. 1. 온도 35$^{\circ}C$와 -5$^{\circ}C$는 상기한 오종의 동물에 대하여 치명적이 아니었다. 2. 본 실험에서 오종의 치사율은 -2$0^{\circ}C$에서 가장 높았다. 3. 동일 온도일 경우 수중에서 보다는 공기 중에서 굴의 생존능력이 더 높았다. 4. 온도가 매우 높거나 낮지 않더라도 반복해서 처리하는 것은 해산 동물에 보다 치명적인 영향을 준다. 그 이유는 그들이 먼저 번의 상해를 회복할 만한 충분한 시간을 가질 수 없기 때문이다. 5. M.Senhousia 는 처음에는 B.amphitrite 보다 저항력이 강하지만 다음에는 B.amphitrite 보다 빨리 저항력을 잃는다. 6. 본 실험에서 얻은 치사율의 계열은 다음과 같다. M.senhousia > B.amphitrite> C.gigas> L.brevicula > A.atrata.

• Korean journal of applied entomology
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• v.5_6
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• pp.33-38
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• 1968

쌀바구미의 유충을 3기로 구분하여 각종 농도의 Apholate를 처리하여 그의 치사율$\cdot$발육속도$\cdot$산란수$\cdot$불임률 및 그의 지속성 여부를 조사하여 다음과 같은 결과를 얻었다. (1) 당대 치사율은 농도가 높아짐에 따라 높아 켰으며, 유령기 처리시의 치사율은 노령기 처리시보다 높았다. (2) 차대 치사율은 처리된 성에 따라 차가 있었고 전체적으로 자충 처리시가 자충 처리시보다 높아 치사돌연변이 유기율이 웅충 처리시에 높아짐을 알 수 있었다. (3) $0.5\%$ 이상의 처리구에서는 우화 성충 중에 각종 기형이 출현하였으며, 그 수는 농도가 높아짐에 따라 컸다. (4) 산란수의 감소는 자충 처리시가 웅충 처리시보다 심하였으며, 이것은 Apholate의 난자형성에 미치는 직접적인 영향이라고 생각된다. (5) 발육속도는 노령기 처리시가 유령기 처리시보다 늦어지며, 그 효과는 농도의 증가에 따라 높아진다. 차대의 생육기간은 자충 처리시가 웅충 처리시보다 길어졌다. (6) 화학적 불임제는 당대의 영향뿐 아니라 차대에도 그 영향력이 지속된다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.3
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• pp.288-293
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• 2010

This paper presents to calculate the lethality of missile for the simulation test program and to verify the simulation results. In order to calculate a reliable lethality we need may data and experiments of fuse and warhead, but in reality it is hard to perform a task. Therefore, this paper obtained from the reference paper to analyze the lethality data for the calculation of the lethality. We form the 6 DOF simulation model using the MATLAB/SIMULINK. And formed the autopilot algorithm using the vertical and horizontal acceleration feedback and PNG (Proportional Navigation Guidance) command be used to the guidance algorithm. Finally, we evaluate the results about three cases, front launch, side launch and rear launch to simulate the simulation program, and the target is designed to have a constant speed and direction.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.4
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• pp.187-192
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• 2006

In order to know the biological effect of effluent from shipyard and the adjacent stream water on four organisms (flatfish, rockfish, sea squirt and arkshell) cultured around the shipyard, lethal rate and DNA damage were measured after 48 hr exposure and carried out by a single cell gel electrophoresis, namely comet assay. $LC_{50}$ (48 hr) could not be calculated in any organism 48 hours after exposure to effluent from shipyard and stream water, because all organism showed a lethal rate lower than 20%. Regardless of no acute toxicity, DNA damage of flatfish and rockfish was detected higher in Jang-Pyoung stream than in control, whereas sea squirt revealed higher DNA damage in laundry waste water. From these results, Jang-Pyoung stream seemed to have a relatively higher genotoxicity rather than effluent from shipyard.

• Korean journal of applied entomology
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• v.13 no.2 s.19
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• pp.89-92
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• 1974

This experiment was carried out to investigate the X-ray sterilization of house fly, Musca domestica when 3-5 days old pupae were irradiated. The results obtained were summerized as follows; 1) Sub-lethal dosage (LD50) for tile pupal mortality were 12.2-13.1 kRad. 2) Sterile dosage (SD90) showed 3. 1kRad in male and such low dosage appears adequate as a sterile dosage. 3) The mortality of male flies was significantly higher than in female at the doses of 4 and 5 kRad.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.45-49
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• 1968

The effect of salinities, temperatures, and turbidities on the mortality of trochophora of oyster, Crassostrea gigas, was investigated at the laboratory. 1. The trochophora of oyster, transferred from normal sea water to sea water of lower or higher salinity, lost their vital activity sooner or later. The mortalities of trochophora were $46\%$ at lower salinity of 15 ppt and $47\%$ at higher salinity of 35 ppt respectively. 2. The high temperature above $40^{\circ}C$ was lethal to trochophora in normal salinity of sea water. Especially all of them died at $45^{\circ}C$ within 30 minutes. However, low temperatures were not lethal to trochophora than higher ones. The differences between two mortality curves at 0.5-and 1-hour treatments at each level of temperatures were not statistically significant as a result of the t-test (P>0.05). 3. It was found that the heavy turbidity (1.0 per cent) did not affect the mortality of the trochophora of oyster in a short period.

• Korean journal of applied entomology
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• v.27 no.4
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• pp.185-189
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• 1988

Laboratory trials were conducted for control of onion maggot and tobacco cutworm with ento¬mogenous nematodes. The onion maggot, Delia antiqua, was exposed to Steinernema feltiae at concentration of 0,30,60, 120 or 240 nematodes per larva, and to Heterorhabditis heliot-hidis at concentration of 0, 10, 20, 40 or 80 nematodes per larva. Mortalities of the maggot ranged from 80 to 100% in S. feltiae and from 63.3 to 100% in H. heliothidis. The tobacco cutworm, SpodoPtera litura was exposed to S. feltiae at concentration of 0,50,100,200 or 400 nematodes per larva and to H. heliothidis at concentration of 0,20,40,80 or 160 nemat¬odes per larva with or without kale in petri dish. The 3rd instar larvae of the tobacco cutworm was more susceptible to both nematode species than the 4th or 5th instar at low concentration. Mortalities of the 3rd instar were 100% in S. feltiae and 67.7-100% in H. heliothidis while those of 4th and 5th instar ranged 76.7-100% and 43.3-100% in S. feltiae, and 36.7-90% and 3.3-90% in H. heliothidis, respectively. Mortalities of the tobacco cutworm larvae decreased when the nematodes were sprayed on the kale leaves in petri dish except 3rd instar.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.59-67
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• 2001

The potential of two entomopathogenic nematodes, Sreinernema carpocapsae Pocheon strain and Heterorhabditis bacteriophora Hamyang strain as biological control agents was evaluated against mushroom ny, Lycoriella mali in laboratory and field. Mortality of L. mali was significantly different according to nematode species, concentration, temperature, and developmental stage of fly S. carpocapsae was more effective than H. bacteriophora. Mortality of L. mali was higher at $25^{\circ}C$ than at $20^{\circ}C$. In addition, the 3rd instal and the 4th instar of L. mali were more susceptible than the 2nd instar. The lowest $LC^{50}$ value was represented by S. carpocapsae, 20.0 infective juveniles (Ijs) in the 3rd instar, 27.5 Ijs in the 4th instar at $25^{\circ}C$. S. carpocapsae infected all the developmental stages of L. mali except egg stage and the 1st instar of larva. The highest mortality was shown in adult female representing 74.0% at$20^{\circ}C$ and 80.0% at $25^{\circ}C$.L. mali female adult was influenced by S. carpocapsae in oviposition. The number of eggs by L. mali female infected by nematodes was much lower than uninfected females. S. carpocapsae was dispersed by infected L. mali adult with higher numbers by females than males. When S. carpocapsae was applied at the rate of $2.25{\times}10^{5}\;and\;4.5{\times}10^{5}\;Ijs/1.5\;\textrm{m}^2$ in the mushroom house, mortalities were 42.2% and 81.6%, respectively. The infective juveniles of nematodes survived for 14 days in the mushroom medium. However, nematodes did not affect mushroom growth.