• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.252-255
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• 2003

Recently, there is a growing trend in the United States toward replacing latex additives in polymer-modified cement mortars with redispersible polymer powders. This movement is relatively new in the U.S. but is further advanced in Europe due to the more extensive use of cement and concrete in residential construction. Hitherto, in Korea - there is a very diminutive movement towards this growing trend. Thus, there is limited availability of data on redispersible polymer powders. This study investigates the effectiveness of redispersible polymer powder on improvement of the mechanical properties of modified mortar. It was concluded from the results of the experiments that the size of the dispersed polymer particles, variations in glass transition points (Tg), and variations in minimum film formation temperature (MFT) influenced the strength development of the modified mortars, and optimum strength in modified mortars using redispersible powders can be achieved when the Tg which accounts for the degree of powder flexibility is considered.

• Fashion & Textile Research Journal
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• v.10 no.5
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• pp.784-795
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• 2008

This study is a thesis about the hair art reflected minimalism which is expanded to various art fields using minimum formative measures minimalism is a kind of modern art trend. It is analyzed theoretically that the works of this researcher approaching minimalism and consideration of minimalism about hair, flexible clothes and artistic costume. It is defined that the "hair art" is "aesthetic hair", and I include my three works approaching minimalism that are researched, extended, made. I spread the works which have minimalism characteristic by design intent, concept, title, color, ingredient, size and detail, consider the hair art works theoretically and present the basis and method of scholar study minimalism art trend. I think that succeeding studies related to the hair art should be continued. I expect that various work activities of hair art artists and scientific breakthrough via theoretical thesis about the work of themselves.

• Journal of Information Science Theory and Practice
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• v.2 no.1
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• pp.35-47
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• 2014

Korean researchers' scientific outputs are increasing rapidly with the growth of both Korea's economy and industry size. This is the time to analyze the scientific output (STEM area) of Korea over the last 40 years. For this analysis, this study used the SCIE database of Web of Science (WoS), which is a representative global Citation Index Service. The objects of analysis are every Korean document published in the SCIE journal, and the research scopes are (1) analysis of citation and subject categories and (2) analysis of co-authorship. Through this study, characteristics such as cited trend and research trend by subject, and the status of collaboration between Korea and other countries including the 50 states of the USA were revealed.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.2
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• pp.618-629
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• 1991

The purpose of this experiment is to understand the distribution of coal particles inside CWM droplet which is believed to be a very important factor controlling the flame stability. CWM slurry is atomized by an air assisted twin fluid nozzle. An experimental rig is designed and fabricated. The mean size of coal particle distribution in CWM slurry, atomizing air pressure, coal particle loading in slurry and sampling position inside spray are main experimental variables. The atomized CWM droplets are sampled on the thin white layer of magnesium oxide by the emergency sampling shutter. The sampled coal particles on magnesium oxide layers are collected into test tubes and dispersed completely by Ultra-Sonicator. The size distribution of coal particles inside droplets are measured by Coulter Counter. The presence of coal particle inside the impressions of droplets on magnesium oxide layer are investigated by photo technique. There are quite many droplets which do not have any coal particles. Those are just water droplets, not CWM droplets. The population ratio of droplets without coal particles to toal number of droplets is strongly affected by the mean size of coal particle distribution in slurry and this ration becomes bigger number as the mean size of coal particles be larger. The size distribution of coal particles inside CWM droplets is not even and depends on the size of droplet. Experimental results show that the larger CWM droplets has droplets has bigger mean value of particle size distribution. This trend becomes more evident as the atomizing air pressure is raised and the mean size of coal particles in CWM slurry is bigger. That is, the distribution of coal particles inside CWM dropolets is very much affected by the atomizing air pressure and the mean size of pulverized coal particles in CWM slurry.

• Archives of Craniofacial Surgery
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• v.23 no.2
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• pp.71-76
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• 2022

Background: Xanthelasma palpebrarum (XP) is a benign periorbital lesion. The relationship between xanthelasma lesion size and serum cholesterol levels has been poorly studied. In this study, we investigated this relationship in the context of the clinical etiology of XP. Methods: We retrospectively reviewed medical records and pathology reports of all patients treated for XP at our hospital between June 2014 and June 2021; the data were used to analyze lesion size, underlying disease, serum cholesterol, and disease recurrence. Results: The mean values for patient age, serum cholesterol, and lesion size were 53.0 years, 235.0 mg/dL, and 69.2 mm², respectively. XP mainly occurred in women (64.7%); furthermore, the incidence of XP and lesion size was greatest among patients in their 5th decade of life (41.2%). There was no statistically significant relationship between xanthelasma lesion size and serum cholesterol level. Conclusion: This study compared lesion size with various clinical features in XP patients. In patients who underwent surgery for XP, serum cholesterol levels tended to be higher than those in the general population. However, the trend between the size of XP and serum cholesterol level was unclear. Therefore, if a patient with XP visits the hospital for surgery, it is recommended to check the lipid profile to confirm underlying dyslipidemia regardless of the size.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.1
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• pp.57-67
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• 2009

Under the supply-oriented policy, efficiency and rationale have not been fully considered in planning of water supply facilities in Korea. As a case, this study shows that large-size systems are suffering from overcapacity problem of water treatment plants, and thus discusses what options should be applied to deal with inefficiency. Water demand of large-size systems has suddenly decreased for the last 10 years while water demand has been often assumed to increase at a regular rate in planning of plants according to excess capacity hypothesis. This inconsistency led to a serious overcapacity. In 2006, total excess capacity of nine large-size systems was more than 1.2 times as large as maximum daily demand of total customers in Seoul. However, their options are expected to stay ex post facto. To prepare the risk of overcapacity, and draw large benefits out of the plants, the authors and other professionals in Korea should further discuss the more adaptive method for prediction of water demand, and systems integration between a large-size system and adjoining systems.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2215-2218
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• 2010

The series of alkali metal perhalogenates, $MXO_4$ (M=Li, Na, K and X=F, Cl, Br, I) were theoretically studied with the help of MP2 methods. Bidentate as well as tridentate structures were found to be stable minima. The bidentate structures are becoming preferred as the size of halogen increases and as the size of metal decreases. Geometrically, the M-O and M-X distances of both bidentate and tridentate structures, increase with the size of metal. Generally, the M-$O_1$ distances of tridentate forms are longer than the corresponding distances of bidentate forms, while the M-X distances of tridentate forms show the opposite trend. Similarly, the X-O bonds increase with the size of halogens except $MXO_4$ pairs, where the X-O bonds are unusually long due to the enhanced oxygen-oxygen repulsions. In short, the relative energetics as well as the geometrical parameters are found to be strongly dependent on halogen and metal elements.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1711-1715
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• 2003

The experiment was designed on 42 non pregnant Black Bengal goat. Out of which 18 were subjected to a superovulatory treatment comprising of eCG and hCG for embryo transfer study. The remaining 24 goats received no treatment and served as control for parameter studied as well as recipient for embryo transfer studies. Important biochemical constituents such as acid and alkaline phosphatase, total protein and cholesterol and inorganic phosphorus were estimated in the follicular fluid of control and treated group and the values were separately recorded for small medium and large size follicle. The results indicated a significant effect on acid phosphotase activity due to size of follicle. The value increased progressively from small to medium and from medium to large follicles. Alkaline phosphotase activity showed reverse trend. Alkaline phosphotase decreased progressively as size increased. The concentration of inorganic phosphorus did not reveal any significant difference between the control and treatment groups and also between the different size follicles. The concentration of protein decreased significantly from small to medium and from medium to large, although no difference was observed between the control and treatment groups. The concentration of Cholesterol in the follicular fluid indicated a significant increase from small to medium and to large follicle. Here also no difference was observed due to treatment. Similar in the composition of follicular fluid in the respect of above mentioned constituents indicated no of super ovulatory treatment on follicular fluid composition.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.373-378
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• 2000

The heat resistant material, in service, may experience static loading, cyclic loading, or a combination of two. An experimental study of crack growth behavior of STS 316L austenitic stainless steel under fatigue, and creep-fatigue loading conditions were carried out on compact tension specimens at various tensile hold times. In the crack growth experiments under hold times. In the crack growth experiments under hold time loading conditions, tensile hold times were ranged from 5 seconds to 100 seconds and its behavior was characterized using the $\Delta$K parameter. The crack growth rates generally increase with increasing hold times. However in this material, the trend of crack growth rates decreases with increasing hold times for short hold time range relatively. It is attributed to a decline in the cyclic crack growth rate as a result of blunting at the crack tip by creep deformation. The effect of grain size on the creep behavior of STS 316L was investigated. Specimens with grain size of 30, 65 and 125${\mu}{\textrm}{m}$ were prepared through various heat treatments and they were tested under various test conditions. The fracture mode of 316L changed from transgranular to intergranular with increasing grain size.

• KIEAE Journal
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• v.11 no.6
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• pp.19-28
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• 2011

This study examines the current status on the supply of community facilities based on the supply criteria of present welfare facilities. Analyzing satisfaction of residents about community facilities based on physical supply criteria. The study sets up the concept and proposed trend of the related studies and distinction through the examination of previous researches. Next, the present systematical supply criteria, was used to make indication in order to propose the promotion of improvement on supply criteria for community facilities. Multi dimensional analyzing system and the satisfaction level of the community facility was used to analyze the relationship between the two. The direction of policy improvement according to the analysis is as per the following. First, it is necessary to improve supply criteria of household to guarantee the minimal amount of space. Second, specification of the minimum distance of community facility to residential area in the complex is needed. Also, the presentation of bottom boundary line of the formation area size to expand the size up to minimal level of size is needed. Third, resident exercise facility supply criteria among the community facility supply criteria need to be improved from the number of household base to the size for each household base. Forth, resident resting facility criteria among the community facility supply criteria should be changed from the present criteria of one facility per five hundred households.