• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.3
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• pp.219-229
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• 2020

Recently, since atopic dermatitis is sensitive to skin irritation, it has been suggested that the development of a patch that can effectively exhibit adhesion and absorption to a specific local area while minimizing skin irritation, and capable of appropriate drug release should be given priority. In this study, we tried to develop a hydrogel patch that minimizes skin irritation, adheres effectively to a specific area, and promotes absorption. The atopic patch was formulated into a super-absorbent hydrogel sheet using a freeze drying method. Cell viability assay was carried out using keratinocytes (HaCaT cell) and fibroblasts (L929 cells). In order to investigate the physical properties, FT-IR, FE-SEM, porosity analysis and swelling behavior were investigated. As a result, the newly prepared HA-Dex hydrogel patch was verified by biocompatibility and physical evaluation. In addition, the manufactured hydrogel patch has sufficient moisture absorption capacity and can relieve itching of atopic skin, and is expected to be applied to various drug delivery products for the treatment of atopic dermatitis in the future.

• Fire Science and Engineering
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• v.26 no.2
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• pp.75-83
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• 2012

An experimental study was conducted to investigate the effects of change in heat release rate on unsteady fire characteristics of under-ventilated fire in a semi-closed compartment. A standard doorway width of the full-scale ISO 9705 room was modified to 0.1 m and the flow rate of heptane fuel was increased linearly with time using a spray nozzle located at the center of enclosure. Temperature, heat flux, species concentrations and heat release rate were continuously measured and then global equivalence ratio (GER) concept was adopted to represent the unsteady thermal and chemical characteristics inside the compartment. It was observed that there was a significant difference in unsteady behavior between global and local combustion efficiency, and the GERs predicted by ideal and measured heat release rate were also shown different results in time. The unsteady behaviors of temperature, heat flux and species concentrations were represented well using the GER concept. It was important to note that CO concentration was gradually decreased with the increase in GER after reaching its maximum value in the range of 2.0~3.0 of global equivalence ratio. In addition, the experimental data on unsteady thermal and chemical behaviors obtained in a semi-closed compartment will be usefully used to validate a realistic fire simulation.

• Journal of the Korean Geotechnical Society
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• v.21 no.6
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• pp.81-91
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• 2005

'Coarse grained material' refers to crushed stones or gravels, and the behaviour of soil containing coarse grained material is not easily defined using the conventional soil mechanics theory due to the influences of large particles, therefore large scale test is essential to investigate their effects. Previous studies have identified the major factors affecting the properties of coarse grained materials by using large scale shear testing apparatus, such as maximum particle size, water content, density and uniformity coefficients. In this paper, the effect of variation of maximum particle size and water content on shear strength was analyzed from the results of large scale shear test. In addition, the fiction coefficient at critical state per vertical load was estimated using the equation proposed by Wood (1998). The sample for the test was obtained from the local quarry sites. Tests results show that the shear strength for 50.8 m maximum particle size is relatively larger than that of 76.3 m and air-dry sample has larger shear strength than saturated sample. In the meantime, the friction coefficient at critical state shows $1.0\sim1.6$ according to the test conditions.

• The Journal of Korean Academic Society of Nursing Education
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• v.6 no.2
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• pp.376-389
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• 2000

The Purpose of this study was to grasp the status of drug uses in college students, and to investigate the knowledge and attitude when they use it. We collected through questionnaires from Sep. 1 to Oct. 30 in 1999. The subjects were 490 college students in Seoul and northern of the Kyunggi-do. The data analysis was performed using SPSS (version 7.0) and ANOVA. The results of this study were as follows. 1. There was no correlation for all factors in the relationship between general characteristics of subjects and knowledge for drugs. On the contrary, in the relation of the general characteristics and attitude for drug of subjects, some factors are statistically significant e.g., department (F=3.049, p<.010), satisfaction for school life (F=6.167,p<.002), body shape(F=8.092, p<.000), and the relationship with ones parents (F=3.728, p<.005). 2. In the analysis of drug use status and knowledge, only in the factor of administration control was statistically significant(F=4.304, p<.014) and in the relation of attitude for drug uses, drug administration was statistically significant (F=4.521, p<.004). 3. In the mean scores for the drug knowledge analysis, the highest factor was 'A narcotic make deformed persons through poisoning of physical and mental' (M=4.14), the lowest factor was 'If catch the flu during the pregnancy, should be take drug as possible as quickly to reduce negative effect for fetal' (M=1.94). 4. In the analysis for drug attitude, the highest factor was 'A drug is alike a poison' (M=3.48), 'Should be keep the usage and dosage of drug' was the lowest (M=1.48). 5. From the investigation for status of drug use, it was revealed that the most subjects (73.6%) were purchase drugs after explain their symptoms to pharmacist. And they take drugs only when they felt painful in 43.1%. The most students (70.4%) were experienced control of drug administration. It was inquired that subjects were mainly obtained information about drugs from pharmacist and television (or radio) advertisement, 33.5% and 33.1%, respectively. In the examination for existence of long-term administrators in their family, 'none' and 'only parents' are 49.6% and 37.3%, respectively. When their parents have illness, the persons go to drugstore and hospital for heath-care, 47.8% and 44.3%, respectively. On the basis of results of this study, we suggest as follows. 1. This study was analyzed data from questionnaires for college students in a part of local areas, so we suggest that the next research should be perform for national-wide students as subjects to generalize the results. 2. It is need more intensive research methodologies such as interview and observation. 3. Additional research is required for knowledge and behaviors of drug uses that will how impact on ones health behavior.

• Journal of Advanced Marine Engineering and Technology
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• v.11 no.2
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• pp.71-81
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• 1987

Nowadays, the high development of industrial technique demands the optimal design of marine structures to be welded under the water, because the underwater welding of the ship hull and marine structures can decrease manpower and cost of production. However there is not available at present any report on fatigue behavior about underwater welded joints. In this paper under tention- tension repeated fatigue stress with frequency of 10 cycles per second by local controlled system, the fatigue strength properties of underwater welded joints of SM41A-2 Plate-to-Plate of 10 mm thickness were experimentally examined. The results obtained were as follows : 1) The fatigue strength of underwater welded joints of SM41A-2 was peaked at the heat input of about 1, 400 joule/mm(180 A, 36 V), while, at the heat input of more than about 1, 100 joule/mm (160 A, 33 V) that of the underwater welds at the higher than cycle of life rather than the lower cycle was higher than that of the base metal but lower than that of the atmosphere welds on account of both cooling and notch effects. 2) The fatigue limit of underwater welds increased with an increase of heat input resulting in a peak of that at the heat input of about 1, 400 joule/mm and then decreased gradually. 3) The fatigue strength at N cycles was peaked between the heat input of about 1, 400 and 1, 700 joule/mm where the strain was rapidly increased. 4) It was confirmed that the optimal zone of heat input condition for obtaining the underwater welds fatigue strength higher than that of the base metal exists, and if out of this zone, the fatigue strength of the underwater welds was lower than that of the base metal because of lack weld penetration, inclusion of slag, voids, etc. 5) By the fatigue test, the underwater welds fractured brittly without visual deformation, so the strain was remarkably less than of the atmosphere welds. 6) The fatigue life factor was peaked at the heat input of about 1, 600 joule/mm (200 A, 36 V) at which the mean strain is a little higher than that of the base metal but quite lower than those of the atmosphere welds, resulting in good underwater welds because both fatigue strength and ductility of the underwater welds are higher than those of the base metal at such heat input.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.12
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• pp.429-460
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• 1999

The letter of credit is quintessentially international. In the absence of international legal system, a private system based on banking practices has evolved, commanding the adherence of the international letter of credit community and providing the foundation of th reputation of this instrument. To maintain this international system, it is vital that international standard banking practice should not be subject to local interpretations that misconstrue or distort it. The UCP is a formulation of international standard banking practice. It is neither positive law nor a "contract term" in any traditional sense and its interpretation must be consonant with its character as a living repositary of international understanding in this field. As a result, the interpretation and application of specific articles of the UCP must be consistent with its evolving character and history and with the principles upon which sound letter of credit practice is predicated. This study, especially, focuses on article 13 and article 14 of the UCP500. Article 13(b) of UCP500 stipulates that banks will have a reasonable time, not to exceed seven days, to examine documents to determine whether they comply facially with the terms of the credit. The seven-day provision is not designed as a safe harbor, because the rule requires the issuer to act within a reasonable time. But, by virtue of the deletion of the preclusion rule in the document examination article in UCP500, however, seven days may evolve as something of a safe harbor, especially for banks that engage in strategic behavior. True, under UCP500 banks are supposed to examine documents within a reasonable time, but there are no consequences in UCP500 for a bank's violation of that duty. It is only in the next provision. Courts might read the preclusion more broadly than the literal reading mentioned here or might fashion a common-law preclusion rule that does not require a showing of detriment. Absent that kind of development, the change in the preclusion rule could have adverse effects on the beneficiary. The penalty, strict estoppel or strict preclusion, under UCP500 and 95UCC differs from the classic estoppel. The classic estoppel rule requires a beneficiary to show three elements. 1. conduct on the part of the issuer that leads the beneficiary to believe that nonconforming documents do conform; 2. reasonable reliance by the beneficiary; and 3. detriment from that reliance. But stict preclusion rule needs not detrimental reliance. This strict estoppel rule is quite strict, and some see it as a fitting pro-beneficiary rule to counterbalance the usually pro-issuer rule of strict compliance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.215-226
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• 2017

This study analyzed trends in agricultural and food marketing studies from 1984 to 2015 using text-mining techniques. Text-mining is a part of Big-data analysis, which is an effective tool to objectively process large amounts of information based on categorization and trend analysis. In the present study, frequency analysis, topic analysis and association rules were conducted. Titles of agricultural and food marketing studies in four journals and reports were used for placing the analysis. The results showed that 1,126 total theses related to agricultural and food marketing could be categorized into six subjects. There were significant changes in research trends before and after the 2000s. While research before 2000s focused on farm and wholesale level marketing, research after the 2000s mainly covered consumption, (processed)food, exports and imports. Local food and school meals are new subjects that are increasingly being studied. Issues regarding agricultural supply and demand were the only subjects investigated in policy research studies. Interest in agricultural supply and demand was lost after the 2000s. A number of studies after the 2010s analyzed consumption, primarily consumption trends and consumer behavior.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.2
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• pp.33-40
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• 2020

Various studies have been conducted on the structural health monitoring using optical fiber. Optical fibers can be used to measure multiple and distributed strain. Among the optical fiber sensors, FBG sensor has advantages of dynamic response measurement and high precision, but the number of measurement points is limited. Distributed fiber sensors, represented by distributed Brillouin sensors, usually have more than 1000 measurement points, but the low sampling rate makes dynamic measurements impossible. In this study, a hybrid nerve sensor system using only the advantages of the FBG sensor and the distributed Brillouin sensor has been proposed. Laboratory experiments were performed to verify the proposed system, and the accuracy and reproducibility were verified by comparing with commercial sensors. Applying the proposed system, dynamic response ambient measurements are used to evaluate the global state of the structure. When an abnormal condition is detected, the local condition of the structure is evaluated by static response measurement using the distributed measurement system. The proposed system can be used for efficient structural health monitoring.

• The Korean Journal of Pain
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• v.7 no.2
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• pp.162-169
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• 1994

Blockade of cervicothoracic sympathetic ganglion (stellate ganglion controls pain on face, head, neck, shoulder, upper limbs, and upper chest, including their viscera and sympathetically maintained pain. This procedure also increases blood flow to the above areas and relieves hyperreactivity of sympathetic nervous system. Clinically, repeated stellate ganglion blocks with local anesthetic agent may become difficult with complications such as accidental intravascular or subdural injection, recurrent laryngeal nerve or bracheal plexus paralysis, pneumothorax and edema on injection site. Therefore, at times long-term cervicothoracic ganglion block with neurolytics is necessitated but its applications are prohibited by the critical structures surrounding ganglion. There are also few reports of neurolytic stellate ganglion block. This study was performed to observe the complications, gross changes of surrounding structures, and microscopic findings of ganglion cells after neurolytic block and to certify the possibility of clinical use of neruolytic stellate ganglion block. The unilateral superior cervical sympathetic ganglion of rabbit was blocked with absolute ethyl alcohol 0.4 ml at the level of cricoid cartilage. Normal ganglion was used as a control and 5 animals were sacrificed at each intervals of 7, 15 and 50 days after block. The results were as follows; 1) All experimental animals showed no specific changes of behavior, motor function. No necrotic tissues were present in the block area during the observation period. There were some gross scar tissues along the fascia of muscles surrounding the needle injection site, but gross atrophy of muscles or injured major vessels were not found. 2) Microscopically, structures of normal ganglion of rabbit were very similar to those of humans. Seven days after absolute ethyl achohol injection there were marked edema of ganglion cells and nuclei with irregular nuclear membrane. Some of the ganglion cells lost their nuclei and showed degenerative changes. Fifteen days after block, cell edema were decreased and loss of the Nissl's body was prominant. The ganglion cell structures looked close to normal but the cytoplasm and nucleus were generally contracted 50 days after block. These results suggest absolute ethyl alcohol injection on cervical sympathetic ganglion with above method mainly blocks pre- and post-synaptic fibers and the long-term neurolytic blockade of this ganglion may be possible in rabbits.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.3
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• pp.25-34
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• 1993

The long-term behavior, such as in excavation problems of weak medium, can be dealt with by the elasto-viscoplasticity models. In this paper, a combined formulation of elasto-viscoplasticity using boundary elements and finite elements without using internal cells is presented. The domain integral introduced due to the viscoplastic stresses is transformed into a boundary integral applying direct integration in cylindrical coordinates. The results of the developed boundary element analysis are compared with those from the explicit solution and from the finite element analysis. It is observed that the boundary element analysis without internal cells results in some error because of its deficiency in handling the nonlinearity in local stress concentration. Therefore, a coupled analysis of boundary elements and finite elements, in which finite elements are used in the area of stress concentration, is developed. The coupled method is applied to a time dependent inelastic problem with semi-infinite boundaries. It results in reasonable solution compared with other methods where relatively higher degree of freedoms are employed. Thus, it is concluded that the combined analysis may be used for such problems in the effective manner.