• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.378-384
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• 2013

This study was conducted to identify the effect of soil water potential on the fruit quality and yield of paprika in summer fertigation cultivation. Treatments of soil water potential during cultivation were composed of -10, -20, and -30 kPa, respectively. The plant height of early growth was increased by high soil water potential (-10 kPa) treatment all of 'Cupra' and 'E499524' (mini-paprika) varieties. Mean fruit weight was increased by -20 kPa soil water potential treatment compared with the other treatments. The fruit number per plant was not affected by soil water potential in 'Cupra' variety but was increased by -20 kPa soil water potential treatment in E499524 variety (mini-paprika). The yield of soil water potential treatment of -20 kPa was higher than those of the other treatments. The flesh thickness and sugar content were not affected by soil water potential in 'Cupra' and 'E499524' (mini-paprika) varieties. The incidence of fruit cracking was decreased with decreasing soil water potential. Mineral contents of plants such as nitrogen, potassium, calcium, magnesium etc. were not affected in soil water potential.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.447-456
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• 2008

Five effective strains against tobacco cutworm, Spodoptera litura (Lepidoptera: Noctuidae), Steinernema carpocapsae (GSN1), Steinernema sp. (GSNUS-10), Steinernema sp. (GSNUS-14), Heterorhabditis bacteriophora Hamyang (HbH), and Heterorhabditis sp. (GSNUH-1) were selected among 14 isolates of Korean entomopathogenic nematode in laboratory tests. $LC_{50}$ values of above five strains against tobacco cutworm were various by different nematode strains and developmental stages of tobacco cutworm. $LC_{50}$ value of S. carpocapsae (GSN1) was the lowest by $4.0{\sim}8.3$ infective juveniles (Ijs) and 2nd instars of tobacco cutworm was most susceptible. Pathogenicity of five effective strains against tobacco cutworm depends on nematode strain, concentration, and application times. The most effective strain was determined as S. carpocapsae (GSN1). Two or three times of applications were effective regardless of nematode strain, or concentration. Efficacy of S. carpocapsae (GSN1), Steinernema (GSNUS-10), Steinernema (GSNUS-14), and Heterorhabditis (GSNUH-1) was variable depending on nematode strain, concentration, application times, and host variety. S. carpocapsae (GSN1) was the most effective and inoculation of 100,000 infective juveniles per m2 (720,000 Ijs/7.2 $m^2=1{\times}10^9$ Ijs/ha) resulted in higher efficacy. Three times of application of nematodes led to higher control efficacy than one or two applications. Efficacy of nematodes was higher on Chinese cabbage than cabbage or kale.

• The korean journal of orthodontics
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• v.36 no.4
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• pp.284-294
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• 2006

Objective: Activating mutations in the fibroblast growth factor receptor-2 (FGFR2) have been shown to cause syndromic craniosynostosis such as Apert and Crouzon syndromes. The purpose of this pilot study was to investigate the resultant phenotypes induced by the two distinctive bone-targeted gene constructs of FGFR2, Pro253Arg and Cys278Phe, corresponding to human Apert and Crouzon syndromes respectively. Methods: Wild type and a transgenic mouse model with normal FGFR2 were used as controls to examine the validity of the microinjection. Micro-CT and morphometric analysis on the skull revealed the following results. Results: Both Apert and Crouzon mutants of FGFR2 induced fusion of calvarial sutures and anteroposteriorly constricted facial dimension, with anterior crossbite present only in Apert mice. Apert mice differed from Crouzon mice and transgenic mice with normal FGFR2 in the anterior cranial base flexure and calvarial flexure angle which implies a possible difference in the pathogenesis of the two mutations. In contrast, the transgenic mice with normal FGFR2 displayed normal craniofacial phenotype. Conclusion: Apert and Crouzon mutations appear to lead to genotype-specific phenotypes, possibly causing the distinctive sites and sequence of synostosis in the calvaria and cranial base. The exact function of the altered FGFR2 at each suture needs further investigation.

• Journal of the Korean Society of Radiology
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• v.11 no.5
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• pp.335-341
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• 2017

Cyclotron is a device that accelerates positrons or neutrons, and is used as a facility for making radioactive drugs having short half-lives. Such radioactive drugs are used for positron emission tomography (PET), which is a medical apparatus. In order to make radioactive drugs from a cyclotron, a nuclear reaction must occur between accelerated positrons and a target. After the reaction, unncessary neutrons are produced. In the present study, radioactivation generated from the collisions between the concrete shielding wall and the positrons and neutrons produced from the cyclotron is investigated. We tracked radioactivated radioactive isotopes by conducting experiments using FLUKA, a type of Monte Carlo simulation. The properties of the concrete shielding wall were comparatively analyzed using materials containing impurities at ppm level and materials that do not contain impurities. The generated radioactivated nuclear species were comparatively analyzed based on the exposure dose affecting human body as a criterion, through RESRAD-Build. The results of experiments showed that the material containing impurities produced a total of 14 radioactive isotopes, and $^{60}Co$(72.50%), $^{134}Cs$(16.75%), $^{54}Mn$(5.60%), $^{152}Eu$(4.08%), $^{154}Eu$(1.07%) accounted for 99.9% of the total dose according to the analysis having the exposure dose affecting human body as criterion. The $^{60}Co$ nuclear species showed the greatest risk of radiation exposure. The material that did not contain impurities produced a total of five nuclear species. Among the five nuclear species, 54Mn accounted for 99.9% of the exposure dose. There is a possibility that Cobalt can be generated by inducive nuclear reaction of positrons through the radioactivation process of $^{56}Fe$ instead of impurities. However, there was no radioactivation because only few positrons reached the concrete wall. The results of comparative analysis on exposure dose with respect to the presence of impurities indicated that the presence of impurities caused approximately 98% higher exposure dose. From this result, the main cause of radioactivation was identified as the small ppm-level amount of impurities.

• Journal of Radiation Protection and Research
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• v.41 no.1
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• pp.49-55
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• 2016

Background: For the purpose of baseline data collection and enhancement of environmental monitoring the distribution studies of $^{137}Cs$ and $^{90}Sr$ in the soil of Uljin province was performed and the relation between surface soil activities and soil properties (pH, TOC and median of the surface soil) was analyzed. Materials and Methods: For 14 spots within 10 km from the NPP surface soil samples were collected and soils for depth profile were sampled for 3 spots in April 2011. Using ${\gamma}$-ray spectrometry with HPGe detector, the concentrations of $^{137}Cs$ were determined and the concentrations of $^{90}Sr$ were measured by counting ${\beta}$-activity of $^{90}Y$ (in equilibrium with $^{90}Sr$) in a gas flow proportional counter. Results and Discussion: The concentration ranges of $^{137}Cs$ and $^{90}Sr$ were $<0.479-39.6Bq{\cdot}(kg-dry)^{-1}$ (avg. $7.51Bq{\cdot}(kg-dry)^{-1}$) and $0.209-1.85Bq{\cdot}(kg-dry)^{-1}$ (avg. $0.74Bq{\cdot}(kg-dry)^{-1}$) which were similar to the reported values from other regions in Korea. The activity ratio of $^{137}Cs$ to $^{90}Sr$ in surface soils was around 9.67, which is much bigger than the initial value of 1.75 for worldwide fallouts because of faster downward movement of $^{90}Sr$ after fallout than that of $^{137}Cs$. For depth profile studies soils were collected down to 40 cm depth for the locations of Deokgu, Hujeong and Maehwa. The $^{137}Cs$ concentration distribution of the first two showed maximum values at top soils and decreased rapidly in exponential manner, while $^{90}Sr$ showed two local maximum values for soils near top and about 30 cm depth. Through linear fittings between the $^{137}Cs$ and $^{90}Sr$ concentrations of surface soil and pH, TOC and median of the surface soil, the only probable relationship obtained was between $^{137}Cs$ and TOC (determination coefficient $R^2=0.6$). Conclusion: The concentration ranges of $^{137}Cs$ and $^{90}Sr$ in Uljin were similar to the reported values from other regions in Korea. The only probable relationship obtained between activities and soil properties was between $^{137}Cs$ and TOC.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.280-294
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• 2001

Despite to the reality that the outbreaks from flood poisoning in Korea have been continuously increasing in the last two decades, it was very much neglected even in the public health field in Korea. Food poisoning outbreaks resulted in many cases not only in the damage of health but also in the death of many lives. However, this problem can be effectively solved by effects through health education activities, but not solely by the legal measures. This study was carried out to provide information that can be used in planning health education programs and proposing new rules to prevent any possible outbreaks from flood poisoning. The main problems contributing to flood poisoning outbreaks in an institutional setting or school catering and at home were reviewed and analyzed through the epidemiological investigations and articles related to flood poisoning in the last a decade (1991 ∼ 2000). Accordingly, the data presented in this study are sufficient to show and prove the significant trends in food poisoning accidents in Korea. The major findings investigated in this study are as follows. The frequency of food poisoning accidents as well as the number of victims have continuously increased in Korea. The number of victims per food poisoning accident is also increased from 20 persons in 1990 to 69.8 persons in 2000. Therefore, we should realize that the group poisoning outbreaks occur more frequently and the size of group poisoning accidents is getting larger. Among four seasons, the food poisoning accidents occurred more frequently in the summer (May ∼September) until 1997, However, after 1997, the food poisoning accidents occurred evenly in three seasons except the winter. The most important bacteria that cause food poisoning in Korea were Salmonella spp., Vibrio spp. and Staphylococcus aureus. They occupied 85∼90% of the rates of accidents and the number of victims.

• Pediatric Infection and Vaccine
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• v.13 no.1
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• pp.71-77
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• 2006

Purpose : Shigellosis is still an important cause of acute food-borne diarrheal diseases throughout the world. We investigated the transmission routes and clinical course through the outbreak of shigellosis in Mapo-Gu, Seoul. Methods : From October 7th to November 19th in 2005, Mapo-Gu public health center had referred 32 patients with confirmed or suspected shigellosis to the National Medical Center. We had investigated source of infection, epidemiology, laboratory findings, and clinical course of the cases occurred during this outbreak. Results : Among 32 patients, 24 patients had been confirmed with shigellosis, 8 patients had been diagnosed with suspected shigellosis. They ranged in age from 5 months to 12 years old and their mean age was 6.5 years. The clinical manifestations were as follows; diarrhea, fever, abdominal pain and asymptomatic condition. Symptoms had sustained for 3.7 days on the average. S. sonnei were cultured by rectal swab and founded to be resistant to ampicillin and TMP/SMX except to 3rd generation cephalosporin. After treatment with antibiotics such as cefixime and ceftriaxone or imipenem and conservative treatment with electrolyte and fluid replacement for 5~7 days, Stool cultures of the rectal swab grew no Shigella in these cases except 3 cases. Conclusion : An outbreak of shigellosis had occurred in a preschool and elementary school children. From the same results of antimicrobial susceptibility and pulsed-field gel electrophoresis patterns in this study, we suggest that the outbreak of shigellosis in this report had been originated from a single strain. According to all negative results about suspected food and water cultures, we couldn't find out source of infection. Through materials offerred by Mapo-Gu Public Health Center, we presumed the trasmission routes probably were person-to-person.

• The Korean Journal of Mycology
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• v.16 no.4
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• pp.220-225
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• 1988

This study was carried out to investigate the effect on the system of crop rotation of sesame(Sesamum indicum L). The results of infected plant percentage and yield of sesame wilting disease, fluctuation of density of Fusarium oxysporum and Actinomycetes, and their pathogenicity test on Fusarium spp isolated from sesame cultural soil were investigated. Density of F. oxysporum was the highest in a sesame continuous cropping soil but that of Actinomycetes was the lowest in that soil. And that of F. oxysporum and Actinomycetes according to investigation date was the highest at June. 30 and July. 30, respectively. Their pathogenicity of F. oxysporum and F. solani isolated from sesame cultural soil to sesame, peanut and green gram were recognized to all isolates except one isolate among F. oxysporum 8 isolates and one isolate to sesame, 2 isolates to peanut and all isolates to green gram among F. solani 4 isolates. F. oxysporum density and infected plant of wilting disease were increased as a result of replanted cultivation of sesame, and yield of that was prominantly reduced. Relation between density of F. oxysporum in cultural soil and infected plant percentage showed positive correlation and yield index highly negative. There was little difference between sesame-upland rice and sesame-peanut in the system of crop rotation.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.9
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• pp.717-722
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• 2001

This paper presents a methodology on the backward path tracking control of a trailer type robot which consists of two parts: a tractor and a trailer. It is difficult to control the motion of a trailer vehicle since its dynamics is non-holonomic. Therefore, in this paper, the modeling and parameter estimation of the system using a real-coded genetic algorithm(RCGA) is proposed and a backward path tracking control algorithm is then obtained based on the linearized model. Experimental results verify the effectiveness of the proposed method.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.4
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• pp.60-73
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• 2011

Since Jeju Ollegil opened in September 2007 and attracted the sensation of popularity throughout the country, the interest in 'Walking Trails' has increased, and the central ministries and the local governments composite and assign various 'Walking Trails'. Walking trails are not tours on which people go to see one spot and move to another spot by vehicle, but a long linear journey that leads people to see, to feel and to experience a region's landscape and culture while walking on the trail. 'Walking Trails' are efficient routes to discover and to use a former way and to link the various ecological regions' histories and cultural resources, so it is most important to select a route. Although the routes were selected by considering the various planning factors and giving each route a specified theme, some problems like the inconvenience of visitors caused by lack of facilities have occurred. After designation and construction of the trails, they were not properly evaluated by visitors. Therefore, it is the purpose of this study to suggest a better way to construct the trails by surveying visitor satisfaction and by analyzing the impact of planning a route on visitor satisfaction at Bukhansan Dulegil which was completed. For this study, with a questionnaire based on the literature review to identify the important planning factors for selecting a route, a survey was conducted on visitor satisfaction for each section and their intention to revisit and to recommend that trail. Based on the characteristics of each section that was identified in the field research, the trails were classified into five types and satisfaction of each type and each type was analyzed. In addition, analyzing the impact of planning factors on satisfaction, the impact of satisfaction on revisiting and recommending and visitors' perception of the theme, further improvement for better construction of the trail was presented. Satisfaction of sectors with strong natural elements was higher; 'walking comfort' was the highest planning factor affecting satisfaction. In addition, satisfaction was surveyed to have high influence on revisiting and recommending.