• Polymer(Korea)
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• v.32 no.4
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• pp.340-346
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• 2008

The aim of this study is to understand the effect of structure on the dispersion of both CNT and GNF in the phase of synthesized polyurethanes matrix. Various CNT/PU and GNF/PU composite films were prepared. Polyurethane having a different hard segment was blended with both CNT and GNF. PU having HDI as hard segment showed good dispersion with both CNT and GNF because of their linear structural character and molecular kinesis while PU having aromatic ring showed poor dispersion with those due to their structural complexity. Structural effect also induced the increase of its electro conductivity. The PU/CNT composite showed a bad dispersion (because of phase separation between PU matrix and CNT) but good electro conductivity at its surface (because CNT was collected on the surface of composite film due to low density of CNT). PU/CNT and PU/GNF composite films have quite low normalized sheet resistance value compared with silver/PU nanocomposite film because the fiber type filler could have much more contact points than that of sphere shaped silver particles have.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.1
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• pp.45-54
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• 2020

Recently, market demands of miniaturization, high interconnection density, and fine pitch of PCBs continuously keep increasing. Therefore, SLP (substrate like PCB) technology using a modified semi additive process (MSAP) has attracted great attention. In particular, SLP technology is essential for the development of high-capacity batteries and 5G technology for smartphones. In this study, the reliability of the microvia of hybrid SLP, which is made of conventional HDI (high density interconnect) and MSAP technologies, was investigated by experimental and numerical analysis. Through thermal cycling reliability test using IST (interconnect stress test) and finite element numerical analysis, the effects of various parameters such as prepreg properties, thickness, number of layers, microvia size, and misalignment on microvia reliability were investigated for optimal design of SLP. As thermal expansion coefficient (CTE) of prepreg decreased, the reliability of microvia increased. The thinner the prepreg thickness, the higher the reliability. Increasing the size of the microvia hole and the pad will alleviate stress and improve reliability. On the other hand, as the number of prepreg layers increased, the reliability of microvia decreased. Also, the larger the misalignment, the lower the reliability. In particular, among these parameters, CTE of prepreg material has the greatest impact on the microvia reliability. The results of numerical stress analysis were in good agreement with the experimental results. As the stress of the microvia decreased, the reliability of the microvia increased. These experimental and numerical results will provide a useful guideline for design and fabrication of SLP substrate.

• The Journal of Internal Korean Medicine
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• v.41 no.4
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• pp.676-687
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• 2020

Objectives: The aim of this study was to report improvement of acute headache incurred in a traffic accident in five patients who underwent inpatient treatment with Korean medicine. Methods: We collected data for traffic accident patients with acute headache who were admitted to the Ja-Seng Hospital of Korean Medicine from November 2019 to April 2020 and received combinational Korean medical treatment. All patients had numerical rating scale (NRS) values of 6 or greater. The patients were treated with acupuncture, pharmacopuncture, herbal medicine, and chuna treatment. We measured the validity of the treatment with the NRS, Headache Impact Test-6 (HIT-6), and Henry Ford Headache Disability Inventory (HDI) at admission and on the date of hospital discharge. Results: At the end of the treatment, all patients showed decreases in NRS, HDI, and HIT scores. Conclusions: The combination of Korean medicine at admission was effective in five patients with acute headache after a traffic accident. However, the number of subjects was insufficient and individual efficacy was not measured in this study. Therefore, further studies are needed on this topic.

• Journal of Acupuncture Research
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• v.27 no.1
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• pp.51-64
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• 2010

Objectives : To introduce and compare various headache measurement tools, in order to provide fundamental information for future clinical trials and development of oriental medicine measurement tools. Methods : Eight headache assessment scales, Migraine-Specific Quality of Life Questionnaire(MQoLQ), Migraine-Specific Quality of Life(MSQOL), Migraine-Specific Quality of Life Questionnaire(MSQ), The Headache Impact Questionnaire(HImQ), Headcahe Needs Assessment Survey(HANA), Henry Ford Headache disability Inventory(HDI), Migraine Disablity Assessment Scale(MIDAS) and Headache Impact Test(HIT-6), were searched through Pubmed. General character, the process of development, verification of reliability, internal consistency, responsiveness to patient's change and validity were reviewed. Results : In assessing the quality of life of migraine patients, MQoLQ can be used to measure the change within 24 hours, MSQ and MSQOL can be used to measure the change during a relatively longer period of time. The frequency and bothersomeness of headache can be easily measured by HANA. HImQ can be used to measure the intensity of headache and the influence on normal daily activities. HDI can measure the emotional difficulties of headache patients. HIT-6 and MIDAS makes measurements possible in a short period of time, and the reliability and validity have been verified numerously. HIT-6 and MIDAS are the most frequently used measurement tools because they are simple and easy for both the assessor and the patient to understand and use. Conclusions : In this study, various headache assessment tools have been reviewed. The assessed tools were widely used after being verified for their reliability and validity. We hope this study provides fundamental information in establishing future clinical trial and clinical practice guidelines. We also hope this study to contribute to the development of an oriental medicine assessment tool for headache.

• Journal of Oriental Neuropsychiatry
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• v.18 no.3
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• pp.331-340
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• 2007

The etiology of chronic headache is not yet fully explained, the treatment of this symptom is not simple. We show the effect of Qigong therapeutics applied on chronic headache patient, in order to establish a primary data for further studies of new treatments. We treated 2 times a weeks for 3 weeks. The acupoints, (太陽穴)(Ex-HN5), (老龍穴), (大趾甲下穴), and (百會穴)(GV20) were stimulated for 10 seconds by Qigong-Acupuncture, and after that Qigong therapy was performed for 30 minutes The effects were analyzed using VAS scores, PPI(Present Pain Intensity), HI(Headache Index) and HDI(The Henry Ford Headache Disability Inventory). We concluded that Qigong therapeutics applied on chronic headache patient showed effects of relieving pain, improving general activities and changing the mood. Further researches are needed to evaluate the distinct functional mechanism of Qigong therapeutics, hut this study is meaningful in the sense that it will act as a fundamental study to build on.

• Korean Journal of Community Nutrition
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• v.2 no.3
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• pp.327-337
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• 1997

The purpose of this study was to investigate the differences in anthropometric, hematologic, and lipidologic data between normocholesterolemia and hypercholesterolemia and influencing factors in hypercholesterolemia in middle-aged men in Kwang-ju. 179 middle-aged men were involved. Anthropometric data(body weight, height, body circumferences and skinfold thickness) and hematologic data(blood pressure, fasting blood glucose, albumin and hemoglobin) were measured. Bleed lipid profile(total cholesterol, tr- iglyceride, phospholipid, HDI-cholesterol, LDL-cholesterol and VLDL-cholesterol) were analyzed. To determined using questionnaire. The subjects were classified as hypercholesterolemic based on The Guideline for Korean Hyperlipidemia. body mass index, systolic blood pressure, waist and hip circumference, and triceps, subcostal, abdomen, subscapular and suprailliac skinfold thicknesses of the hypercholesterolemic group were significantly higher than in the normocholesterolemic group. The concentrat- ion of cholesterol, triglyceride, phospholipod. HDL-cholesterol, LDL-cholesterol and VLDL -cholesterol of the hypercholesterolemic group were significantly higher than normocholesterolemic group. The concentration of cholesterol has a significantly positive correlation with body mass index, diastolic blood pressure, waist circumference, waist/thigh ratio and skinfold thickness(triceps, subcostal, abdomen, and supraillic skin- fold thickness). The general tendency of socioeconomec status, frequencyu of meat intake, smoking amounts and duration and duration and drinking frequencies and amount were higher in the hypercholesteolemic group but not significant. In conclusion, hypercholesterolemia in middle-aged men was closely correlated with upper body fat obesity and most of them had an accompanied high triglyceride level tendency.

• Fibers and Polymers
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• v.1 no.1
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• pp.12-17
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• 2000

Thermotropic polyurethanes were synthesized from 1,6-hexane diisocyanate (HDI) as a diisocyanate, 1,6-hexane diol (HD), and rigid diols containing imide unit such as N,N＇-bis(4-hydroxyphenyl)-3,4,3＇,4＇-biphenyl-dicarboxyimide (BPDI) or bis-N-(4-hydroxyphenyl)-4,4＇-oxydiphthalimide (ODPI). The effects of structure difference between BPDI and ODPI and composition of HD/BPDl (ODPI) on the thermal and liquid crystalline behavior were studied. Thermotropic polyurethanes with an inherent viscosity of 0.59~0.70 were obtained. The melting temperature of BPDI-based polyurethanes were in the range of 150~$290^{\circ}C$, however, those of ODPI-based polyurethanes were in the range of 150~$190^{\circ}C$. All the polyurethanes based on ODPI (25~100 mole %) clearly exhibited a stable liquid crystalline phase, and BPDI-based polyurethane having 5-25% of BPDT showed a mesophase. The melting and isotropization temperatures ($T_m$, $T_i$) and ΔT($T_i$ - $T_m$) increased with increasing BPDI and ODPI content. The polyurethanes based on BPDI has higher melting points and thermal stability compared to ODPI-based polyurethanes.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.10
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• pp.785-790
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• 2003

This paper presents an approach to optimally design the air-hearing surface (ABS) of the optical flying head for near-field recording technology (NFR) NFR is an optical recording technology using very small beam spot size by overcoming the limit of beam diffraction. One of the most important problems in NFR Is a head disk interface (HDI) issue over the recording band during the operation. A multi-criteria optimization problem is formulated to enhance the flying performances over the entire recording band during the steady state. The optimal solution of the slider, whose target flying height is 50 nm, is automatically obtained. The flying height during the steady state operation becomes closer to the target values than those for the Initial one. The pitch and roll angles are also kept within suitable ranges over the recording band. Especially. all of the all-hearing stiffness are drastically increased by the optimized geometry of the air hearing surface.

• Archives of Plastic Surgery
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• v.35 no.6
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• pp.729-734
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• 2008

Purpose: The evaluation and management of a completely transected tendon of the hand is relatively clear. In most cases, the integrity is assessed by physical examination(eg, broken normal cascade, motion loss) but occasionally, It happens in troubles. because of pain, limited patient cooperation(eg, child, unconscious patient), and other associated injuries(eg, fractures, foreign bodies). Methods: From september 2006 to August 2007, 28 patients were evaluated with real time ultrasonography preoperatively and postoperatively. Twenty eight patients with injured tendon were evaluated using an HDI 5000 Sono CT(Philips Medical Systems, Bothell, WA) machine with a high resolution, 7.5MHz hockey stick linear probe. Dynamic evaluation was performed in real time. Results: Surgery was performed after the ultrasonographic evaluation. Sonographic diagnosis and intraoperative findings were correlated. Ultrasonographic findings show tendon discontinuity, gaps, and fluid collection. Conclusion: We conclude that ultrasonography is helpful in evaluating and managing acute tendon injury. Especially, in cases of completely lacerated tendon, ultrasonography can identify the location of the proximal tendon stump and partial lacerated tendon, ultrasonographic diagnostic tool can decrease misdiagnosis.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.5
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• pp.660-666
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• 2009

Thermoplastic polyurethane elastomer(PU-TPE) and energetic thermoplastic polyurethane Elastomer(E-PU-TPE) were prepared from Hexamethylene diisocyanate(HDI), 1,4-BD/AA ester polyol and glycidyl azide polymer(GAP-2400) as an energetic material by the addition polymerization. The PU-TPE and E-PU-TPE were characterized by FT-IR and GPC. Viscometer, DSC and UTM were used to investigate the viscose behavior with a various solvent, thermal properties and mechanical properties of PU-TPE and E-PU-TPE, which are of potential interest for the development of high performance binder of energetic solid propellants. It was found that $M_w$ of PU-TPE and E-PU-TPEs are over 100,000 and decreased with increase of GAP-2400 contents. $T_m$ and ${\Delta}H$ as thermal properties decreased and also tensile strength and elongation at break as mechanical properties decreased with increase of GAP-2400 contents.