• Journal of ILASS-Korea
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• v.1 no.2
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• pp.24-32
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• 1996

Most of the research of small engines to date focused on developing spark ignition engines occupied much parts. Recently the number of a small direct injection diesel engine applied in small cars has been increased and considered as a next generation power source for passenger cars because of its high efficiency. Therefore the combustion chamber becomes smaller and the fuel injection pressure goes higher, which makes fuel sprays impinged easily on the combustion chamber walls. When strong swirls are not induced, the fuel may not mix with air because of fuel deposition on the wall. As a positive way, the combustion chamber systems which is using spray wall impaction has been introduced and assessed by an experimental or a simulate manner. In these systems the raised lands are positioned in tile chamber for spray impaction in order to break up the fuel drops into much smaller and direct them into desirable direction. This study addresses to the effects of rho position and size of the raised land or glow plug to help the chamber design using spray wall impaction. The characteristics of the spray impinged on various lands are investigated and compared with each other. Then the chamber shapes are discussed with the characteristics and their proper position and size is proposed in any chamber volume.

• Korean Journal of Clinical Laboratory Science
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• v.45 no.4
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• pp.170-179
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• 2013

There is a correct way to avoid any sequale in the central motor area during neurosurgery procedures. A clear way to find the circumference of the central sulcus, central motor, and sensory areas by giving cortical electrical stimulation to the central motor area immediate after surgery is proposed. Looking at patients who underwent brain surgery September 2009 to July 2013, the central sulcus and speech areas around the central area of the brain was investigated, using the practices of either a localized brain map check or a direct cortical electrical stimulation test. Brain maps localized around the surgical site through functional movement or speech areas were identified. Accurate tests done during surgery without damage to motor neurons or after surgery were conducted smoothly. Although successful brain map test localization can be accomplished, there are some factors that can interfere. The following phenomena can reverse the phase: (1) the first sensory / motor in the case of patients severe nerve damage; (2) placement of the electrode on top of the vessel; (3) presence of a brain tumor near the brain cortex; (4) use of anesthesia if patient cooperation is difficult; and (5) location of the electrode position and stimulus is inappropriate.

• Journal of the Korean Solar Energy Society
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• v.21 no.4
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• pp.73-83
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• 2001

Since the solar radiation is the main input for sizing any solar system, it will be necessary to understand and evaluate the insolation data. The horizontal global insolation data have been measured since May, 1982 and direct normal solar insolation data since December 1990 at 16 different sites all over the country and considerable effort has been made for constructing a standard value from measured data at each station. In the results, the average global total solar radiation of the nation is $3,055kcal/m^2.day(12.79MJ/m^2.day)$ and the average clear day direct normal solar beam radiation was $4,600kcal/m^2.day(19.26MJ/m^2.day)$, which indicates possible solar energy application of medium and high temperature technologies with high concentration.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.4
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• pp.165-170
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• 2004

This paper presents summary results of direct interview survey of Korean industrial customers conducted to evaluate the direct and short duration interruption costs resulting from local random electrical supply interruptions. The cost is evaluated using the questionnaires authors designed, which are mainly on the experience or preparatory actions consumers predicted they would take. Economic evaluation of reliability that traditionally takes into account duration and frequency of interruption does not accurately reflect the lost value or economic impacts of industrial customer, especially large size, caused by any kind of interruption. So, to imply the substantial difference in costs incurred by different customer group, the authors apply the international standards, i.e. IEC, IEEE, to the analysis on the interruption costs.

• Archives of Plastic Surgery
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• v.47 no.5
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• pp.435-443
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• 2020

Background The innervated radial artery superficial palmar branch (iRASP) flap was designed to provide consistent innervation by the palmar cutaneous branch of the median nerve (PCMN) to a glabrous skin flap. The iRASP flap is used to achieve coverage of diverse volar defects of digits. However, unexpected anatomical variations can affect flap survival and outcomes. Methods Cases in which patients received iRASP flaps since April 1, 2014 were retrospectively investigated by reviewing the operation notes and intraoperative photographs. The injury type, flap dimensions, arterial and neural anatomy, secondary procedures, and complications were evaluated. Results Twenty-eight cases were reviewed, and no flap failures were observed. The observed anatomical variations were the absence of a direct skin perforator, large-diameter radial artery superficial palmar branch (RASP), and the PCMN not being a single branch. Debulking procedures were performed in 16 cases (57.1%) due to flap bulkiness. Conclusions In some cases, an excessively large RASP artery was observed, even when there was no direct skin perforator from the RASP or variation in the PCMN. These findings should facilitate application of the iRASP flap, as well as any surgical procedures that involve potential damage to the PCMN in the inter-thenar crease region. Additional clinical cases will provide further clarification regarding potential anatomical variations.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.2
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• pp.160-168
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• 2014

Objectives: Chemical hazard evaluations are important for workers' health and working environments. Allyl chloride (CAS No. 107-05-1) is used in many industries, leading to concerns about the possibility of threats to the health of workers. Since only insufficient or controversial information is available about potential related hazards, an in vitro mammalian chromosomal aberration (CA) assay was conducted in order to gain additional information concerning any such hazards. Moreover, toxicological information from this study could be applied for workers' rights to know, and to prepare or update the Materials Safety Data Sheet (MSDS) for a number of industries. Methods and Results: The assay was performed using the Chinese hamster lung fibroblast cell (ATCC, CRL-1935), by the direct method (-S9) and by the metabolic activated method (+S9 mix). Using the direct method, the seven dosages in the 48-hour treatment group did not show that the frequency of CA is proportionate to the dosage. The frequency of CA is not proportionate to the dosage addition for a six-hour treatment using the metabolic activated method. Conclusions: From these findings, it was decided that this chemical does not induce chromosomal aberrations under the tested conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.1
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• pp.22-27
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• 2012

The experiment involved observations of 2,514 Holstein-Friesian cows to determine the effects of environmental factors (cow's age, calving season, weight and sex of calves, housing system) and genetic factors on gestation length in dairy cattle and the correlation between gestation length and other reproductive traits (calving ease, stillbirth rates and placental expulsion). Genetic parameters were estimated based on the sires of calved cows (indirect effect) and the sires of live-born calves (direct effect). The following factors were found to contribute to prolonged gestation: increasing cow's age, male fetuses and growing fetus weight. Optimal gestation length was determined in the range of 275-277 days based on calving ease and stillbirth rates. The heritability of gestation length was estimated at 0.201-0.210 by the direct effect and 0.055-0.073 by the indirect effect. The resulting genetic correlations suggest that the efforts to optimize (prolong) gestation length could exert an adverse influence on the breeding value of bulls by increasing perinatal mortality and calving difficulty. The standard errors of the investigated parameters were relatively high, suggesting that any attempts to modify gestation length for the purpose of improving calving ease and reducing stillbirth rates should be introduced with great caution.

• Journal of Korea Multimedia Society
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• v.8 no.6
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• pp.790-797
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• 2005

It is well-known that there are many similarities between Japanese and Korean language. For example, the order of words and the nature of the grammatical conjugation of both languages are almost the same. Another similarity is the frequent omission of the subject from a sentence. Moreover, both languages have honorific expressions and the identical concept for expressing nouns in terms of Chinese characters. Using these similarities, we have developed a word-to-word translation system which does away with any deep level analysis of syntactic and semantic structures of the two languages. If we use these similarities, the direct translation method is superior to the internal language translation method or transfer-based translation method. Although the MT system based on the direct translation method is more easily developed than the ones based on other methods, it may have a lot of difficulties when it tries to select the appropriate target word from ambiguous source verbs. In this paper, we propose a new algorithm to extract the meaning of substantives and to make use of the order of the extracted meaning. We could select $86.5\%$ appropriate verbs in the sample sentences from IPAL-verb-dictionary. $13.5\%$ indicates the cases in which we could not distinguish the meaning of substantives. We are convinced, however, that the succeeding rate can be increased by getting rid of the meaning of verbs thatare not used so often.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.39.2-39.2
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• 2011

With the steady increase in the demand for flexible devices, mainly in display panels, researchers have focused on finding a novel material that have excellent electrical properties even when it is bended or stretched, along with superior mechanical and thermal properties. Graphene, a single-layered two-dimensional carbon lattice, has recently attracted tremendous research interest in this respect. However, the limitations in the growing method of graphene, mainly chemical vapor deposition on transition metal catalysts, has posed severe problems in terms of device integration, due to the laborious transfer process that may damage and contaminate the graphene layer. In addition, to lower the overall cost, a fabrication technique that supports low temperature and low vacuum is required, which is the main reason why solution-based process for graphene layer deposition has become the hot issue. Nonetheless, a direct deposition method of large area, few-layered, and uniform graphene layers has not been reported yet, along with a convenient method of patterning them. Here, we report an evaporation-induced technique for directly depositing few layers of graphene nanosheets with excellent uniformity and thickness controllability on any substrate. The printed graphene nanosheets can be patterned into desired shapes and structures, which can be directly applicable as flexible and transparent electrode. To illustrate such potential, the transport properties and resistivity of the deposited graphene layers have been investigated according to their thickness. The induced internal flow of the graphene solution during tis evaporation allows uniform deposition with which its thickness, and thus resistivity can be tuned by controlling the composition ratio of the solute and solvent.

• Korean Journal of Veterinary Research
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• v.43 no.4
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• pp.579-585
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• 2003

The studies were carried out on the correlation between microsomal lipid peroxidation level and drug metabolizing enzyme activities in rat liver microsomal suspensions on various ages (2-week-old, 2, 4, 8, and 12-month-old). The lipid peroxidation levels of liver homogenates tended to be elevated in a 4-month-old rat livers, but it was a little decreased in 8 and 12-month-old rat livers. The lipid peroxidation levels of microsomal suspension was not shown any significant differences by ages. Lipid peroxidation levels and microsomal cytochrome P450 and NADPH-cytochrome c reductase activity showed a direct correlation (r=0.72 and r=0.64), respectively. The activities of cytochrome P450-dependent aminopyrine-N-demethylase and benzpyrene hydroxylase in rat liver microsomes were increased by ages up to 8-month-old rats and maintained in 12-month-old rats. The correlation between lipid peroxidation levels and these cytochrome-dependent enzyme activities showed a high direct correlation (r=0.97 and r=0.81), respectively.