• Journal of the Korean Society for Precision Engineering
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• v.16 no.3 s.96
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• pp.103-108
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• 1999

A problem in the grinding with a small diametric wheel is the decrease of wheel speed. In order to resolve this problem, an accelerating unit which increases the wheel speed is recommended. In this paper, the accelerating effect of an accelerating unit has been investigated through the side-cut grinding experiments performed with a vitrified bonded CBN wheel in a machining center(MC). The static stiffness, normal force, and machining error were measured in the experiments. As the accelerating unit is attached on the column of machining center, the static stiffness of tool system is largely decreased. But as the wheel speed increased by the accelerating unit, this problem is overcome and machining efficiency is improved. The lesser the quill stiffness was, the higher the accelerating effect became.

• Bulletin of the Korean Chemical Society
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• v.20 no.9
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• pp.1010-1016
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• 1999

We synthesized the photoresponsive side chain polymers containing aminonitro azobenzene for studying the effect of temperature on photoinduced birefringence. Four different copolymers were prepared using methacrylate, α-methylstyrene, and itaconate monomer. Photoisomerization was observed under the exposure of UV light using UV-VIS absorption spectroscopy. Reorientation of polar azobenzene molecules induced optical anisotropy under a linearly polarized light at 532 nm. The change of the birefringence was observed with increasing the sample temperature under a continuous irradiation of excitation light. We could estimate the activation energy of molecular motion in thermal and photochemical mode. Besides the effect of glass transition temperature on the activation energy, we focused our interests on the effect of geometrical hindrance of polar azobenzene molecules and cooperative motion of environmental mesogenic molecules in the vicinity of polar azobenzene molecules.

• Journal of Radiation Industry
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• v.9 no.4
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• pp.193-198
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• 2015

Most of targeted therapies block the action of certain enzymes, proteins, or other molecules involved in the growth and spread of cancer cells to produce its cytotoxic effect. Either small molecule drugs or monoclonal antibodies are mostly used in targeted therapies. Unfortunately, targeted therapy has a certain degree of unwanted side effect like other cytotoxicity inducing chemotherapies. To overcome and to reduce unwanted side effects during a cancer therapy, recently radiopeptide therapies has got the worlds' attraction for the tumor targeting modalities due to its beneficial effect on less side effect compared to cytotoxic chemotherapies. Among radiopeptide therapies, $^{177}Lu$-DOTATATE is a major modality as an effective one invented so far in treating neuroendocrine tumor (NET) and it has been in clinical trials at least one decade. Although it does have rather effective therapeutic effect on NET, it has less effective in rather large solid tumor. There are many ways to improve or increase therapeutic effect of radiopeptide are a finding the potent small molecules to target the tumor site selectively, or a labeling with radioisotope of emitting high energy, or an improving its biological half-life by introducing different moieties to increase lipophilicity. Present study was focus to increase a biological half-life of radio somatostatin which will target the somatostatin receptor by altering the bifunctional chelator (BFCA) by introducing lipophilic moiety to the somatostatin, which would make the labeled peptide stay longer in the tumor site and thus it can intensify the therapeutic effect on tumor cell itself and around tissues.

• Journal of radiological science and technology
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• v.43 no.3
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• pp.155-159
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• 2020

The purpose of this study is to investigate the effect of posture changes(Anteroposterior projection, Posteroanterior projection) in the plain abdominal examination on breast dose and to examine its clinical usefulness. This study was used a human body phantom and a glass dosimeter. Glass dosimeters were directly inserted from the center and outside of medial and lateral. In this study, the deep dose was measured in the right breast and the surface dose in the left breast. During the abdominal examination, the central X-ray incident point was perpendicularly incident to the image receptor 5 cm above the iliac crest. The exposure parameters were 82 kVp, 320 mA, 50 ms, x-ray field size 14×17 inch The distance between the center X-ray and the detector was fixed at 110 cm, and only the top two AEC chambers were used. As a result of this study, the medial and lateral side doses of the right breast were 535.73±30.68 μGy and 414.46±33.52 μGy for erect AP, and 145.80±18.52 μGy and 148.76±12.92 μGy in erect PA. The superficial breast dose was 754.00±68.36 μGy on the medial side and 674.06±45.58 μGy on the lateral side in the erect AP, 70.66±7.98 μGy on the medial side, and 86.46±15.35 μGy on the lateral side in the erect PA. There was a statistically significant difference in the difference between the mean values of the medial and lateral side doses in the deep and superficial areas of the breast according to the postural change (p <0.01). As a result of this study, If the abdominal radiography was examined in the PA position, the dose reduction effect was 72.78% on the medial side, 64.10% on the lateral side of the deep breast, 90.62% on the medial side, and 87.17% on the lateral side of the superficial breast compared to the AP position.

• Restorative Dentistry and Endodontics
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• v.20 no.2
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• pp.768-779
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• 1995

This study was performed to investigate the effect of root canal shaping techniques on the change of the shape of prepared root canal. 40 mesiobuccal canals of recently extracted mandibular 1st and 2nd molars were divided into 4 groups and shaped by step-down/balanced force technique, step-down/step-back technique, step-back technique and conventional technique respectively. The change of the shape of root canal was traced by superimposing the radiographs obtained before and after shaping of each root canal. The results were as follows. 1. By the experimented techniques except conventional technique, the root canals were more shaped in convex side of apical area and in concave side of most curved and coronal area than in the other sides(P<0.05). By conventional technique, the root canals were more shaped in convex side than in convave side from apex to orifice(P<0.05). 2. By step-down/balanced force technique, the cancave sides at C and D points of proximal view and C point of clinical view were more shaped than the convex side(P<0.05). Through the entire canal, the concave side was more shaped than the convex side in proximal view(P<0.01). But there was no statistical difference between both sides in clinical view. 3. By step-down/step-back technique, the change of root canal shape was not statistically different in concave and convex sides at each point of both views(P>0.05). And through the entire canal in proximal view, there was no statistical difference in shaping percentage between both sides. But through the entire canal in clinical view, the concave side was more shaped than the convex side(P<0.1). 4. By step-back technique, the convex side at B point of clinical more shaped than the other sides(P<0.05). Through the entire canal in proximal and clinical views, there was no statistical difference in shaping percentage between both sides. 5. Comparing the total shaping percentage among techniques, that in conventional technique was the greatest numerically, and followed by the percentages in step-down/step-back, step-down/balanced force and step-back technique. But, in proximal view, shaping percentages were not statistically different among techniques(P>0.05, ANOVA test). In clinical view, shaping percentages in step-back and conventional techniques were statistically different(P<0.01, ANOVA test). * Proximal view: radiograph taken in mesiodistal direction. * Clincal view: radiograph taken in faciolingual direction. A point : 1mm point from radiographic apex B point : center point between A and C points C point : most curved point of root canal D point : center point between C point and canal oriffice.

• Proceedings of the Ginseng society Conference
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• 1980.09a
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• pp.1-3
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• 1980

To investigate the effect of ginseng on blood pressure (B.P.) in spontaneously hypertensive rat (SHR) and essential hypertension ginseng extract was given per se daily in 58 SHR and 35 essential hypertensive patients. SHR were divided into 5 groups according to the dosage of ginseng. In essential hypertension 1,000mg of ginseng extract was given. The B.P. in SHR was measured by tail cuff method. In essential hypertension side effect and changes in various laboratory examinations were evaluated. In SHR ginseng appeared to have hypertensive effect when it is given in small amount(10mg/kg). However, when it is given 60mg/kg/day or more difinite B.P. lowering effect was observed. The hypotensive effect was dosedependant and it lasted for 37days of observation. In essential hypertension in 12 $(80\%)$ among 15 patients hypotensive effect was seen with ginseng administration along and the effect lasted for 12 weeks. In the rest of hypertensive patients it is required addition of diuretics of other antihypertensive drugs to decrease B.P., no appreciable side effect was seen. In laboratory examinations no significant changes were seen except for serum cholesterol, ${\alpha}-and\;{\beta}-lipoprotein,$ and hematocrit. There was some evidence of relationship between plasma renin activity (PRA) and ginseng in hypotensive action.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.3
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• pp.100-114
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• 1996

Besides insufficient water, water contamination confronts us with 'water crises' of both quantity and quality. However, the daily water consumption per capita of Korea is greater than that of other developed countries. Because of the current low water price, which is lower than a half of production cost, not only does it become difficult to cope promptly with rapidly increasing water demand and water contamination, but it also causes waste of water. We should, therefore, switch over from supply side management-oriented policy to demand side management-oriented policy through a raise of the water rate. This study carries out a cost analysis based on fair return method which is the principle of water pricing in Korea, and it estimates, through equilibrium analysis, long run marginal cost(LRMC), which satisfies allocative efficiency and reflects true social cost to additional one-unit water supply. Based on the results, this study proposes that the estimated LRMC is the optimal price level in water pricing, which is the most important of the demand side management policies. In the end, water conservation effect, price pervasive effect, and social welfare effect are analyzed.

• The Journal of Korean Physical Therapy
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• v.19 no.5
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• pp.11-19
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• 2007

Purpose: The purpose of this study was to examine effect of trunk control using pelvic movements upon the foot pressure in patients with hemiplegia. Methods: Twelve males with hemiplegia were the procedure executed turnk control using pelvic movements. The foot pressure were measured using Parotec-system. Results: The data were analysed with paired t-test. First, there was a significant increase in external and internal sensors of dynamic foot pressure change of the hindfoot before and after therapy. Also there was significant increase in hallux (p<0.05). Second, there was a significant increase of affected side in support phase(p<0.05) and decreased of affected side in overlapping phase(p<0.05). Third, there was a significant increase in foot floor contact time and impulse pressure rate between affected and non affected side(p<0.05). Conclusion: The trunk control with pelvic movement had an significant effect on the legs by increase activities of hip flexors and abductors. Also had an effect on ankle dorsiflexion and plantar flexor by biomechanical movement.

• Journal of Ginseng Research
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• v.36 no.3
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• pp.308-313
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• 2012

Fresh (raw roots), white (dried), and red (steamed-drid) ginseng samples were gamma-irradiated at 0 to 7 kGy. Electron spin resonance (ESR) technique was used to characterize the irradiation status of the samples, targeting the radiation-induced cellulose radicals after different sample pretreatments. All non-irradiated samples exhibited a single central signal (g=2.006), whose intensity showed significant increase upon irradiation. The ESR spectra from the radiation-induced cellulose radicals, with two side peaks (g=2.0201 and g=1.9851) equally spaced (${\pm}3mT$) from the central signal, were also observed in the irradiated samples. The core sample analyzed after alcoholic-extraction produced the best results for irradiated fresh ginseng samples. In the case of irradiated white and red ginseng samples, the central (natural) and radiation-induced (two-side peaks corresponding to cellulose radical) signal intensities showed little improvement on alcoholic-extraction. The water-washing step minimized the effect of $Mn^{2+}$, but reduced the intensity of side peaks making them difficult to indentify. The effect of different origins was negligible, however harvesting year showed a clear effect on radiation-induced ESR signals.

• Herbal Formula Science
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• v.19 no.1
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• pp.103-111
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• 2011

Objectives : The purpose of this report was to provide the information of activity and safety of galgeun-tang by analyzing domestic/international papers and theses about galgeun-tang. Methods : Domestic/international papers and theses related to galgeun-tang were reviewed and analyzed. These papers were then classified by efficacy, or clinical trials. Results : The basic pharmacological experiment showed antipyretic, analgesic and anti-virus and anti-oxidant efficacy of galgeun-tang. In the case report of galgeun-tang, it showed therapeutic effect for patient with chronic rhinitis. But administration of galgeun-tang induced pruritic eruption in the two case report as a side effects of galgeun-tang. Conclutions : galgeun-tang showed tantipyretic, analgesic and anti-virus and anti-oxidant efficacy in the basic pharmacological experiment. Also, galgeun-tang showed therapeutic effect for patient with chronic rhinitis. But it was reported that galgeun-tang induced pruritic eruption in two case report, so physicians should be aware of the potential side effects.