• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.1
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• pp.81-87
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• 2018

The objective of this article is to provide analytical tools for the scattering of stratum corneum (SC) and to check whether the optical clearing agents (OCAs) could be applied in optics affecting the scattering reduction. Dark field images of tape striped corneocyte separates scattered light of the SC from others in vitro. Several optical clearing agents were tested to reduce the scattering. Physical properties of SC such as water contents, keratin configuration and volume after OCAs treatment were investigated by FT-IR and 3D laser microscope. Several reducing sugars, monomeric sugars, sugar alcohol, and hyaluronic acid, which were used as humectants in cosmetic field, also reduced scattering. However, unlike dehydration in optics, water penetrated into the keratin in SC and scattering was decreased at low concentration of OCAs. In that condition, the volume of corneocyte was increased and stiffness seemed to decrease. The analyzing of tape-stripped SC, showed the change of optical and physical properties of corneocyte by optical clearing agents. The hydration of SC layer by optical clearing agents decreased the scattering of corneocyte and thus improved the skin appearance and moisturizing effect, which are important benefits in the cosmetic field and could provide new possibility to develop skin care study targeting at SC.

• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.3
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• pp.11-19
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• 2009

Recently, concerns relating to the maintenance of large structures have been increased. In addition, the number of large structures that need to be evaluated for their structural safety due to natural disasters and structural deterioration has been rapidly increasing. It is common for the structural characteristics of an older large structure to differ from the characteristics in the initial design stage, and changes in dynamic characteristics may result from a reduction in stiffness due to cracks on the materials. The process of deterioration of such structures enables the detection of damaged locations, as well as a quantitative evaluation. One of the typical measuring instruments used for the monitoring of bridges and buildings is the dynamic measurement system. Conventional dynamic measurement systems require considerable cabling to facilitate a direct connection between sensor and DAQ logger. For this reason, a method of measuring structural responses from a remote distance without the mounted sensors is needed. In terms of non-contact methods that are applicable to dynamic response measurement, the methods using the doppler effect of a laser or a GPS are commonly used. However, such methods could not be generally applied to bridge structures because of their costs and inaccuracies. Alternatively, a method using a visual image can be economical as well as feasible for measuring vibration signals of inaccessible bridge structures and extracting their dynamic characteristics. Many studies have been conducted using camera visual signals instead of conventional mounted sensors. However, these studies have been focused on measuring displacement response by an image processing technique after recording a position of the target mounted on the structure, in which the number of measurement targets may be limited. Therefore, in this study, a model experiment was carried out to verify the measurement algorithm for measuring multi-point displacement responses by using a DIC (Digital Image Correlation) technique.

• Tuberculosis and Respiratory Diseases
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• v.49 no.2
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• pp.162-168
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• 2000

Background : Joint symptoms frequently occur in the course of antituberculous chemotherapy and tend to be ignored and overlooked, but in some cases, they are often very troublesome in obstructing ordinary life. Joint symptoms that develop during antituberculous chemotherapy need to be understood, but there are few materials describing them systematically. Method : This study enrolled 33 patients with tuberculosis treated with first line antituberculous agents for more than 6months. In the course of treatment, joint symptoms not associated with specific cause, such as preexisting joint disease or trauma, were investigated and compared with thæe of the asymptomatic group. We confirmed the incidence of joint symptoms and factors associated with them. Results : Nineteen of 33 patients (58%) had joint symptoms. Joint symptoms developed 1.9$\pm$1.4 months after the beginning of chemotherapy and lasted for 3.6$\pm$2.5months. In 18 of 19 symptomatic patients, multiple joints were involved: shoulder (10 patients, 53%), knee (10, 53%), finger (6, 32 %). Joint symptoms were expressed as pain (19 patiens, 100%), stiffness (7, 37%) and/or swelling (3, 16%). Fourteen patients (74%) took analgesics to relieve their symptoms and in 2 patients, antituberculous agents were discontinued because of the severity of their symptoms. The symptoms seem to be caused by agents other than pyrazinamide, but it was very difficult to identify the definite causative agent. In age, sex, underlying disease and serum uric acid level, no significant differences were noted between the two groups. Conclusions : Although joint symptoms are common during antituberculous chemotherapy, their development is difficult to predict. Because some joint symptoms can become very bothersome, the physician should pay close attention to these symptoms.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.6
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• pp.1045-1058
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• 2017

This paper is a study on railway tunnel behavior characteristic of shallow overburden under the existing road. In order to understand the behavior characteristics of the ground deformation during tunnel excavation, a horizontal rod extensometers were installed in the passage area of the shallow overburden tunnel under the road, and the measurement and analysis were carried out. To compare the in situ measurement, three dimensional numerical analysis with ground condition and construction step was carried out using MIDAS NX. As a result of the field measurement, large preceding settlement occurred where the poor ground condition with shallow overburden excavation has been conducted. As a result of the numerical analysis, the largest settlement occurred at the shallow overburden point where the ground condition was poor. Therefore, in the shallow overburden section where the soil condition is poor and a sufficient depth can't be secured and the arching effect of the ground around the tunnel can't be expected, careful attention should be paid to the application of stiffness reinforcement measures and to minimize ground loosening.

• Journal of the Korean Society for Railway
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• v.17 no.4
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• pp.251-259
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• 2014

The transition zone between an earthwork and a bridge effect to the vehicle's running stability because support stiffness of the roadbed is suddenly changed. The design criteria for the transition structure on ballast track were not particular in the past. However with the introduction of concrete track is introduced, it requires there is a higher performance level required because of maintenance and running stability. In this present paper, a transition structure reinforced with geosynthetics is suggested to improve the performance of existing bridge-earthwork transition structures. The suggested transition structure, in which there is reinforcing of the approach block using high-tension geosynthetics, has a structure similar to that of earth reinforced abutments. The utilized backfill materials are cement treated soil and gravel. These materials are used to reduce water intrusion into the approach block and to increase the recycling of surplus earth materials. An experiment was performed under the same conditions in order to allow a comparison of this new structure with the existing transition structure. Evaluation items are elastic displacement, cumulative settlement, and earth pressure. As for the results of the real-scale accelerated testing, the suggested transition structure has excellent performance for the reduction of earth pressure and settlement. Above all, it has high resistance the variation of the water content.

• Journal of Acupuncture Research
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• v.25 no.4
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• pp.81-94
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• 2008

Rheumatoid arthritis(RA) is a general, chronic, inflammatory and auto-immune disease and it can lead to joint edema, pain, stiffness which are caused by an inflammation in synovium covering our joints. Ulmus davidiana Planchon is a traditional herb used for the treatment on various inflammations, gastrointestinal trouble, ENT(ear, nose, and throat) disease, edema, cancer etc. and it works effectively on arthritis as well. In these study to search for the treatment efficacy of Ulmus davidiana Planchon in RA, I measure manifestation of cytokine gene in synoviocyte treated with Ulmus davidiana Planchon herbal acupuncture and in EL-4 cell, manifestation of cytokine gene cell related to T-cell. And after Ulmus davidiana Planchon herbal acupuncture treatment in Collagen induced arthritis(CIA) which has been known by a general model of RA, DBA mice, I observed foot thickness, general shape of synovium, early cytokine induce CIA and, generation and mutation of cytokine related to the control of T-cell specialization. It comes to conclusion as belows. 1. In synovium treated with Ulmus davidiana Planchon herbal acupuncture, there was the decrease in MIF mRNA does-dependently. Incase of CIA mice treated with Ulmus davidiana Planchon herbal acupuncture, there were the decrease in the damage in synovium and generation of the MIF which is related to induction of the early RA cytokine and IL-6 proinflammatory cytokine. 2. In case of EL-4 treated with Ulmus davidiana Planchon herbal acupuncture, there were decrease in the manifestation of the IL-2 mRNA, but the increase in the manifestation of the IL-4 does-dependently. 3. In the synovium of CIA mice treated with Ulmus davidiana Planchon herbal acupuncture, there were the decrease in generation of IL-2, IL-12 and CD-28, but the increase in generation of IL-4. These result suggest that Ulmus davidiana Planchon can block the process of the early RA by Inhibiting MIF activation, and mitigate Rheumatoid Arthritis by controlling Tcell specialization.

• Journal of Radiation Protection and Research
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• v.26 no.4
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• pp.367-374
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• 2001

The study was designed to evaluate the response of sucralfate against the esophageal damage of rat by irradiation. Sixty Sprague-Dawley rats weighing 200-250 gm were divided into six groups including only sucralfate group, the group of 10 Gy or 20 Gy radiation alone, the groups of 10 Gy or 20 Gy radiation-sucralfate combination, and control. Each group was sacrificed at 3, 7, 14, and 28 days after irradiation. For evaluation of the radiation-induced esophageal lesions, there were examined the change of body weight, barium-esophagogram and histopathologic findings. Mean body weight gain was decreased in the groups with 10 Gy or 20 Gy radiation alone and 10 Gy or 20 Gy radiation-sucralfate combination as comparing with control (p=0.03, p=0.02, p=0.04, p=0.02), but there was no difference between the groups of 10 Gy or 20 Gy radiation alone and the groups of 10 Gy or 20 Gy radiation-sucralfate combination. In the 10 Gy and 20 Gy radiation alone groups, barium esophagograms showed diffuse narrowing and stiffness through the entire esophagus from 7 days after irradiation, but there was similar pattern of esophagograms between the groups of 10 Gy radiation-sucralfate combination and the control. Histopathoiogic lesion scores of 10 Gy and 20 Gy radiation groups were significantly higher than the control (p=0.03, p=0.008). In the 10 Gy radiation group, there were significantly higher lesion scores at 3 and 7 days after irradiation as comparing with those in the group of radiation-sucralfate combination (p=0.04, p=0.03). These results suggest that sucralfate might be played as a role of protection from acute radiation-induced esophagitis within the limit of tolerable radiation doses.

• Journal of Biomedical Engineering Research
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• v.21 no.4
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• pp.391-401
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• 2000

Flow through compliant tubes with linear taper in wall thickness is numerically simulated by finite element analysis. For verification of the numerical method, flow through a compliant stenotic vessel is simulated and the results are compared to the existing experimental data. Steady two-dimensional flow in a collapsible channel with initial tension is also simulated and the results are compared with numerical solutions from the literature. Computational results show that as cross-sectional area decreases with the reduction in downstream pressure, flow rate increases and reaches the maximum when the speed index (mean velocity divided by wave speed) is near the unity at the point of minimum cross-section area, indicating the flow limitation or choking (flow speed equals wave speed) in one-dimensional studies. for further reductions in downstream pressure, flow rate decreases. The flow limitation or choking consist of the main reasons of waterfall effect which occurs in the airways, capillaries of lung, and other veins. Cross-sectional narrowing is significant but localized. When the ratio of downstream-to-upstream wall thickness is 2, the area throat is located near the downstream end. As this ratio is increased to 3, the constriction moves to the upstream end of the tube.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.21-26
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• 2018

Thermoplastic starch (TPS) was prepared by mixing starch with glycerol as a plasticizer. The glycerol content ranged from 20 to 35 wt. % and TPS was prepared in a twin screw extruder. The shear viscosity, thermal and mechanical properties of the TPS were investigated. The viscosity of TPS exhibited typical shear thinning behavior: decreasing viscosity with increasing shear rate. The power index, n, increased with increasing glycerol content. This is because as the content of glycerol, a Newtonian fluid, increases, the viscosity behavior of the TPS becomes closer to that of a Newtonian fluid. The thermal behavior of TPS showed that starch and glycerol are miscible. In addition, when TPS was aged for more than one day at room temperature, TPS showed a partially miscible phase structure. The moisture absorbed into the TPS was assumed to change the phase behavior. The mechanical properties of TPS were found to be strongly dependent on the content of the plasticizer. Both the toughness and stiffness increased with increasing plasticizer content. DSC showed that this unusual result was due to the combined effect of humidity and the high amylose content in starch.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.282-289
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• 2014

After being laminated with a combination of glass fiber reinforced plastic and plywood, the GFRP laminated plate was densificated for 1 hour at $150^{\circ}C$ with pressure of $1.96N/mm^2$. A partial reinforced beam was produced by attaching the 5 GFRP laminated plates to the joint of glulam and the column. In addition, the column to beam joint was produced by using reinforced laminated wooden pin which was made of GFRP sheet and plywood, fiber glass reinforced cylindrical-LVL column. The joint was made of round log, glulam and drift pin as the reference specimen, and its moment resistance was evaluated. As a result, the strength performance of specimens with partial reinforced beams were 1.8 times stronger than the reference specimen on average. Furthermore, rupture was neither occurred on partial reinforced beam nor column. Toughness and stiffness of joints were also fine. The GFRP sheet reinforced laminated plate showed better reinforcement effect than GFRP textile reinforced one. GFRP sheet was inserted into each layer of laminate, and it showed good condition in rotation-angle and strength, therefore it is the most appropriate to reinforce the part of the beam.