• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.5
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• pp.1032-1043
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• 1989

The heat transfer characteristics of the drag reducing polymer solutions are investigated experimentally in the thermal entrance region of circular tube flows. Fluids used in experiments are the aqueous solutions of high molecular polymer, polyacrylamide Separan AP-273 and the range of polymer concentrations is from 20 to 1000 wppm. Two stainless steel tubes with inside diameter 8.5mm(L/D=712) and 10.3mm(L/D=1160) are used for the heat transfer flow loops. The flow loop is set up to measure friction factors and heat transfer coefficients of test sections in two different modes; the recirculating flow system and once-through flow system. The test tubes are heated directly by electricity to apply the constant heat flux boundary conditions to the wall. Three different types of adaptors are used to observe the effects of the upstream flow conditions of the heat transfer test sections. The viscosity and characteristic relaxation time of the test fluids circulating in the flow system are measured by the capillary tube viscometer and falling ball viscometer at regular time intervals. The installed adaptors exhibit slight effect on the entrance heat transfer of Newtonian fluid. However, no noticeable effects are observed for the entrance heat transfer of the drag reducing fluids. The order of magnitude of the thermal entrance lengths of the drag reducing fluids which follow the minimum friction asymptote is much longer than that of Newtonian fluids in turbulent flows. A new dimensionless parameter, the viscoelastic Graetz number, is defined and all the experimental data are recasted in terms of the viscoelastic Graetz number. The local Nusselt number of the viscoelastic fluids is represented as a function of flow behavior index n and the viscoelastic Graetz number. As degradation continues the viscosity and the characteristic relaxation time of the testing fluids decrease. Weissenberg number defined by the relaxation time and D/V appears to be a proper dimensionless parameter in describing degradation effects on heat transfer of the viscoelastic fluids.

• Science of Emotion and Sensibility
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• v.22 no.1
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• pp.55-64
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• 2019

Stress is accompanied by changes in the responses of the autonomic nervous system, and the heart rate variability (HRV) index is a quantitative marker that reflects autonomic responses induced by stressors. In this study, we observed changes in the autonomic responses induced by combinations of 30% oxygen administration and color light for stress relaxation. In all, 42 participants produced stress symptoms over the preceding two weeks, as rated on the stress response scale. After stress assessment, they were exposed to three therapeutic conditions, and electrocardiogram (ECG) signals were recorded before, during, and after therapy. The three therapy conditions consisted of only 30% oxygen administration with white light, a combination of 30% oxygen and orange light, and a combination of 30% oxygen and blue light. The HRV indices extracted from ECG signals were heart rate (HR), the standard deviation of the RR interval (SDNN), the mean square root of consecutive RR interval difference values (RMSSD), the low frequency component of HRV (LF), the high frequency component (HF), and the LF/HF ratio. These indicators were used to compare mean values before and after therapy. The results showed that HR and the LF/HF ratio were significantly lower after therapy than before it. In particular, the condition with 30% oxygen and blue light yielded significantly greater RMSSD and HF increases, as well as decreases in LF/HF ratio than in other two conditions. Our results suggest that therapy with 30% oxygen and blue light is the most effective for the relaxation of stress, which implies autonomic balance by parasympathetic activation.

• Journal of Korean Clinical Health Science
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• v.5 no.4
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• pp.991-997
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• 2017

Purpose. The purpose of this study was to muscle properties analysis of SCM(sternocleidomastoid) Muscle according to posture type when using smartphone. Methods. This study was conducted on 73 college students who are using smartphone. Subjects were analyzed myotonPRO to confirm, prone posture group, stand posture group, drop head above $45^{\circ}$in sit posture on a chair group and drop head below $45^{\circ}$in sit posture on a chair group were measured SCM muscle. The myotonPRO were measured one measurer, total 3 times. Comparative analysis of the each groups were investigated of SCM muscle properties. Results. We found that Frequency, Stiffness, Creep and Relaxation were appeared difference in each posture. F index was increased at drop head below $45^{\circ}$group than stand posture group. S index was increased at drop head above $45^{\circ}$group than prone posture group. C index was decreased at drop head below $45^{\circ}$group and drop head above $45^{\circ}$group than prone posture group. R index was decreased at drop head above $45^{\circ}$group than prone posture group. Conclusions. The muscle properties were appeared difference in each posture of SCM muscle using smartphone.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.353-357
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• 2004

The construction competition is more deepened with the enterprise possibility increase which it follows in the regulation relaxation back against the construction market penetration which carries and the instability of market is added an extra weight and it solves the aspect where also the profitability which is caused by with low price bidding decreases. Against a productivity with the overcome plan it is researched plentifully and the far for a productivity improvement, there is so far to construction, the productivity being used with only include meaning, is to a practical affairs and the application ver)r as the level which is feeble is a possibility of doing. It is like that and the research develops the producing district possibility of new steel-frame work and in the actuality which sees the production volume of steel-frame work and a construction accomplishment process effectively and to be right numerical figures it does it plans it controls and manages the place ultimate objective which it puts.

• The Korean Journal of Health Service Management
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• v.8 no.2
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• pp.175-185
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• 2014

This study analyzed individual happiness exponent according to local residents' perception degree of Health-Cities. The data, which is accumulated by the survey on relationship between happiness and perception degree of Health-Cities targeting 662 of local residents living in Y-gu in Busan, were analyzed using PASW 18.0. The results are as follows. To begin with, the results of Correlation Analysis on the relation between happiness index and cognition degree of Health-Cites indicate that the higher perception of Health-Cities'facilities, administrations, services, education, health environment and transportation the local residents have, the lower individual happiness index they acquired. The cognition degree of transportation has effects on local society and daily life; the cognition degree of facilities and businesses has impact on financial stability. The cognition degree of administrations has influence on psychological relaxation, services have meaningful effects on psychological stability, work and residence, education have statistically meaningful effects on psychological stability, families and marriage, individual human relationships in respect.

• Journal of Korean Physical Therapy Science
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• v.16 no.4
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• pp.1-9
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• 2009

Background: The purpose of this study is to find out the effect on the improvement in idiopathic scoliosis when applying the orthopedic manual physical therapy and myofascial release technique. Methods: 20 patients in Cheon-An ${\bigcirc}{\bigcirc}$ hospital were selected as subjects whose Cobb's angle were higher than $10^{\circ}$ according to the radiograph. They were treated for 60 minutes a day, three days a week, and 8 weeks so that the total time of visit would be 24. We performed five tests (Moire test, X-ray, standing height test, Cobb's angle, pelvic level test, VAS) to indentifiy the therapeutic effects. Results: Four test results were improved more remarkably after those treatment than before(p<.001), except pelvic level test (p>.001). Conclusion: we confirmed that there were correcting effects on most of the valuation index from the primary analysis, which divided the subjects into 2 groups by Cobb's angle, but there were more effective in patients having lower than $25^{\circ}$. There were similarly correcting effects on most of the valuation index according to the secondary analysis, but there were particularly more effective in children.

• Journal of Oriental Neuropsychiatry
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• v.20 no.2
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• pp.177-186
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• 2009

Objectives : We investigated if korean traditional treatment and psychotherapy is effective in patients with depression and menopausal symptoms. Methods : We treated two patients with typical korean traditional medical treatment( Acupuncture, Giungoroen therapy(至言高論療法), Moxibustion ) and progressive muscle relaxation. Results : After treatment, the chief complaint and accompanying symptoms were subsided and improved. BDI score and Kupperman's index were decreased. Conclusions : We may conclude that korean traditional treatment and psychotherapy is effective in patients with depression and menopausal symptoms.

• The Korean Journal of Pharmacology
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• v.11 no.2
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• pp.41-46
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• 1975

The isolated strips of tortoise intestine are evaluated as a test organ for bioassay of prostaglandin $E_1$. This preparation responded highly sensitively to $PGE_1$ and $PGE_2$ in picogram concentration range. The mean slope and the value of precision index among the doses of 0.1, 0.3 and 0.5ng/ml in final concentration were 37.7 and 0.143, respectively. And this was relatively insensitive to different prostaglandins; $E_1/E_2{\gtrsim}1$, $E_1/A_2{\sim}50$ and $E_1/F_{2\alpha}{\sim}100$, and showed the dual responses to 5-hydroxytryptamine and histamine; initial contraction followed by relaxation. The dose-ratio inducing the relative equal contraction height for $PGE_1$, acetylcholine, caerulein, angiotensin and barium chloride was 0.4 : 50 : 25 : 10 : 100 in this order. These results suggest that the intestinal strips of the tortoise are suitable for bioassay of prostaglandin $E_1$ and $E_2$ between the doses of 0.1 and 1.0 ng/ml level in the tissue extracts.

• Journal of Korean Institute of Industrial Engineers
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• v.18 no.2
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• pp.43-49
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• 1992

Edge coloring problem is to find a minimum cardinality coloring of the edges of a graph so that any pair of edges incident to a common node do not have the same colors. Edge coloring problem is NP-hard, hence it is unlikely that there exists a polynomial time algorithm. We formulate the problem as a covering of the edges by matchings and find valid inequalities for the convex hull of feasible solutions. We show that adding the valid inequalities to the linear programming relaxation is enough to determine the minimum coloring number(chromatic index). We also propose a method to use the valid inequalities as cutting planes and do the branch and bound search implicitly. An example is given to show how the method works.

• Journal of Korea Trade
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• v.23 no.4
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• pp.115-130
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• 2019

Purpose - This paper examines the impact of labor market regulations on FDI and the production of foreign firms. Design/methodology - We use an index of employment protection along with data on the FDI and production of foreign affiliates that are provided by the OECD. Findings - The empirical results show that strict employment protection discourages both the production and initial entry of foreign firms, with its impact on production being larger than that on the initial entry decision. The result is robust to various specifications in which instrumental variable estimations are used by applying a unionization rate and a severance pay for redundancy dismissal as instruments, respectively. Therefore, policymakers should not limit their focus to tax incentives, cash grants, and relaxation of market regulations, but they should also extend their attention to labor market deregulation and decreasing non-wage cost to attract more foreign firms into their countries. Originality/value - This paper attempts to answer the question on the impact of employment protection rules on the foreign firm's decisions regarding production as well as initial entry.