• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.786-790
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• 2016

This paper discusses numerically explored orientation effects on the thermal performance of hollow hybrid fin heat sinks (HHFHSs) under natural convection. A HHFHS consists of an array of hollow pin fins concatenated with plate fins and having perforations near the fin bases. Orientation effects on the footprint-based and mass-based thermal performance of the HHFHS were numerically studied for orientation angles ranging from $0^{\circ}$ to $180^{\circ}$. The performance of the HHFHS was compared with that of a pin fin heat sink (PFHS) having similar physical parameters. The results show that the thermal resistance of the HHFHS did not vary considerably from $0^{\circ}$ to $45^{\circ}$. The thermal resistance increased from $45^{\circ}$ to $90^{\circ}$, reached its maximum at $90^{\circ}$, and decreased consistently from $90^{\circ}$ to $180^{\circ}$. Dissimilar behaviors of the thermal resistance of the HHFHS vs. the PFHS resulted mainly from the effect of heat pumping induced by the internal flows of the hollow fins. Despite various orientations, the mass-based thermal resistance of the HHFHS was found to be nearly 30% smaller than that of the PFHS. This result shows the feasibility of the HHFHS for the lightweight thermal management of electronics under natural convection.

• Clinical and Experimental Pediatrics
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• v.45 no.5
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• pp.629-636
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• 2002

Purpose : Our study was aimed to investigate the characteristics of seizures as well as to determine whether the expression of neuronal nitric oxide synthase expression(nNOS) of hippocampus has an affect in the hyperthermic seizure in developing rat. Methods : Hyperthermic seizures were repeatedly induced twice a week for four weeks in 20-day old Spraque-Dowley rats. Fifty two rats were used as a hyperthermic group and 30 rats used as a normothermic control group. Hyperthermic seizures were induced in a water bath at $45^{\circ}C{\pm}1$ for 4 min. The characteristics of seizures were recorded. Using western blot, hippocampal nNOS expression was measured in normothermic control, hyperthermic non-seizure, and hyperthermic seizure groups, respectively. Results : Eighty seven percent of hyperthermia exposed rats showed generalized tonic-clonic seizure most frequently. The duration of seizure was ranged from 12 to 145 sec(mean 55 sec) and the latency to seizure ranged from 158 to 240 sec(mean 204 sec). The duration of seizure was prolonged but there was no significant difference in the seizure latency as the rat exposed more number of hyperthermia. Interestingly, the expression level of hippocampal nNOS in hyperthermic seizure and hyperthermic non-seizure groups was not different from each other, however, the expression in these groups was lower than that of the control group. Conclusion : Our results indicate that nNOS do not have an affect in this repeated hyperthermic seizures. Further studies are required to clarify a role of nNOS in hyperthermic seizure.

• Child Health Nursing Research
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• v.20 no.2
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• pp.113-122
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• 2014

Purpose: Purposes of this study were to identify the level of parental fever phobia and to investigate the relationship between level of parental concern about fever and related variables. Methods: Participants were 151 parents of children who visited a pediatric outpatient clinic. A selfreported structured questionnaire was used for data collection and data were analyzed using descriptive statistics and ${\chi}^2$-test. Results: Almost half of participants defined a minimum temperature for fever as $37.8^{\circ}C$ and a minimum temperature for high fever as $38.9^{\circ}C$. About 75% of participants identified harmful effects of fever as seizure and brain damage, were 'very worried' about fever, measured their child's temperature every hour or less, provided tepid massage and woke children to give antipyretics during febrile illness. There were significant relationships between level of parental concerns about fever and prior experience of febrile seizures, and/or being parents of a single child. Conclusion: Results indicate that fever phobia is prevalent among parents. Further studies are needed to develop and evaluate childhood fever management educational programs for parents. Considering health care providers as a primary information resource about fever management, health care providers should play a vital role to reduce parental unrealistic concerns about fever.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.2
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• pp.143-149
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• 2020

The study examined the seasonal pattern of larvae, nymph, and adult life stages for Haemaphysalis longicornis and the rate of infection with severe fever from the thrombocytopenia syndrome virus in ticks collected from 12 sections (Jichukdong), 14 sections (Uldaeri), and 18 sections (Howondong) in Bukhansan dullegil for April-October 2019. Haemaphysalis longicornis ticks have been considered the main vector for severe fever with thrombocytopenia syndrome (SFTS). Haemaphysalis flava and Ixodes nipponensis were collected using the dragging and flagging method. The ratios of Haemaphysalis longicornis of the collected ticks were 91% (Jichukdong), 94% (Uldaeri), and 98% (Howondong). Monthly distributional studies of Haemaphysalis longicornis based on the developmental stage showed that the adults peaked in September while nymphs were collected more frequently from April through June. The larvae peaked in September and October. SFTS virus detection was performed using 2 × OneStep RT-PCR and nested PCR. On the other hand, no SFTS virus-specific gene was detected in 1,158 ticks of Haemaphysalis longicornis. This result provides estimates of the population densities for the life stages of Haemaphysalis longicornis and the associated disease risk in Bukhansan dullegil, where many people have visited since opening in 2010.

• The Korean Journal of Zoology
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• v.27 no.3
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• pp.137-150
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• 1984

The present experiments were carried out to understand the genetic structure of the natural population by means of the frequencies of recessive lethal and sterility genes on the second chromosomes of Drosophila melanogaster. The natural populations used for experiment were Anyang, Kimpo and Ulsan populations in 1982 and 1983. The mean frequencies of deleterious gene (lethal plus semilethal) were estimated 29.01% in Anyang, 30.07% in Kimpo and 32.31% in Ulsan population. Allelism rates on the chromosome between lethals extracted from natural populations were examined within or between populations. The mean allelism rates were showed 2.28% in Anyang, 1.90% in Kimpo and 2.17% in Ulsan. The values of elimination $(IQ^2)$ were estimated by frequencies of deleterious genes and allelism rates. The mean values of elimination were 0.0020 in Anyang, 0.0019 in Kimpo and 0.0023 in Ulsan population. The effective population size was estimated by using a formula by Nei. Anyang, Kimpo and Ulsan populations were about 2, 900, 3, 600 and 3, 200, respecively. These data suggest that Korean populations of Drosophila melanogaster attained to stable breeding units of intermediate size, ranging from 2, 900 to 3, 600 pairs of fertile individuals.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.512-520
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• 2020

Recently, the applications of the standing column well (SCW) ground heat exchanger (GHX) have increased significantly in Korea as a heat transfer mechanism of ground source heat pump systems (GSHP) because of its high heat capacity and efficiency. Among the various design and operating parameters, bleeding was found to be the most important parameter for improving the thermal performance, such as ground thermal conductivity and borehole thermal resistance. In this study, a bleeding analysis model was developed using the thermal response test data, and the effects of bleeding rates and bleeding locations on the thermal performance of anSCW were investigated. The results show that, when the ground water flows into the top of anSCW, the time variation of circulating water temperature decreased with increasing bleeding rate, and the ground thermal conductivity increases by as much as 179% with a 30% bleeding rate. When the ground water flows into the bottom of the SCW, the circulating water temperatures become almost constant after the increase in the beginning time because the circulating water exchanges heat with the ground structure before mixing with the ground water at the bottom.

• Korean journal of applied entomology
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• v.59 no.3
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• pp.233-241
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• 2020

Several hard tick species in Ixodidae are medically important pests that transmit infectious disease including severe fever with thrombocytopenia syndrome (SFTS). In Korea, the number of SFTS patients continues to steadily increase since its first report in 2013, and Gyeongsangbuk-do (province) is the second most frequent area of SFTS patient occurrence. In order to investigate the distribution of ticks in Sangju city, we collected ticks using the flagging method from 26 sites comprising urban green area, vulnerable area of management, and rural area, and examined SFTS virus from the collected ticks in 2019. Based on Collection Index (CI = tick number / 1 h / 2 people), CI 143 ticks, including Haemaphysalis longicornis, Haemaphysalis flava, and Ixodes nipponensis, were collected; the most abundant species among the three tick species was H. longicornis (CI 138, 96.5%). Ninety two percent (CI 131) of ticks were collected in vulnerable area of management, where people cannot easily enter and are not managed by city hall, whereas only 8.4% (CI 12) were collected in the urban green area and rural area. Regarding SFTS virus detection, virus was not investigated from 26 pools containing CI 143 ticks. The results of this study are expected to be used as a recommendation for ensuring the safety of local residents from tick-borne diseases.

• Applied Chemistry for Engineering
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• v.27 no.1
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• pp.35-38
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• 2016

In this study, the mica used as a thermal-insulation material was modified with a silane coupling agent, octyltriethoxysilane (OTES), to improve its hydrophobicity. The modified mica was characterized using FT-IR spectrometer, water wettability test, and water contact angle measurement. The analysis exhibits that OTES for the modified mica sample was well bonded chemically and drastically enhanced the hydrophobicity. The reflectance observed as 73.9% (mica) and 86.4% (OTES/mica), respectively, for OTES/mica was improved about 12.5% before any modifications. Also the modified mica sample showed $7.2^{\circ}C$ decrease in the thermal-insulation performance of cool paints compared to that of using unmodified mica, indicating that the modification of mica with silane coupling agents could be effective in enhancing the thermal-insulation performance of the cool paint.

• Journal of Energy Engineering
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• v.5 no.1
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• pp.8-18
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• 1996

As a part of comprehensive IGCC process simulation, the thermal performance analysis was performed for coal gas firing combined power plant. The combined cycle analyzed consisted of il Texaco gasifier and a low temperature gas cleanup system for the gasification block and a GE 7FA gas turbine, a HRSG and steam turbine for the power block. A steady state simulator called ASPEN(Advanced System for Process Engineering) code was used to simulate IGCC processes. Composed IGCC configuration included air integration between ASU and gas turbine and steam integration between gasifier, gas clean up and steam turbine. The results showed 20% increase in terms of gas turbine power output(MWe) comparing with natural gas case based on same heat input. The results were compared with other study results which Bechtel Canada Inc. performed for Nova Scotia power plant in 1991 and the consistency was identified within two studies. As a result, the analysing method used in this study is verified as a sound tool for commercial IGCC process evaluation.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.2
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• pp.222-228
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• 2000

Ectodermal dysplasia is a hereditary disease characterized by a congenital dysplasia of one or more ectodermal structures and their accessory appendages. At least 120 subtypes of ectodermal dysplasia have been reported. The disease is usually transmitted as an X-linked recessive trait in which the gene is carried by the female and manifested in the male. Hypohidrotic ectodermal dysplasia is manifested as a triad of defects that include hypohidrosis, hypotrichosis and hypodontia. The characteristic facial features consist of asteatosis, onchodysplasia, sparse and fine blond hair, prominent forehead, a depressed nasal bridge, thick everted lips. The patient may suffer from dry skin, hyperthermia and unexplained high fever as a result of the deficiency of sweat glands. This case report presents detailed procedures of rehabilitating functional and esthetic defect of a 6-year-old boy with hypohidrotic ectodermal dysplasia along with the review of relevant literatures.