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An Effect of Appropriability on R&D Collaboration and Product Innovation Performance: Focusing on the Moderated Mediation Effect of Government R&D Support (전유성이 연구개발협력 및 제품혁신성과에 미치는 영향: 정부 연구개발지원의 조절된 매개효과를 중심으로)

  • Kim, Won;Jung, Sunyang
    • Journal of Technology Innovation
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    • v.25 no.1
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    • pp.1-34
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    • 2017
  • It is almost impossible for firms to possess all of resources and capabilities needed to create technological innovations in modern competitive environment. This situation forces firms to conduct R&D collaboration. Therefore, this paper analyzes an effect of appropriability protecting knowledge exclusively on R&D collaboration and product innovation performance. In addition, we investigate how the governmental R&D support moderates and influences those relationships through empirical analysis. The results of moderated mediation show that the impact of appropriability on product innovation performance appears to be a common pattern in each conditional indirect effect of appropriability regardless of financial, direct, indirect R&D support of the government. The more governmental R&D supports increase over a certain level, the more conditional indirect effects of appropriability on product innovation performance increase through the vertical R&D collaboration. However, conditional indirect effects of appropriability through horizontal R&D collaboration are not significant in all levels of government R&D supports. If we utilize an analysis of moderated mediation by applying governmental R&D supports as a moderator, it is possible to analyze a significant strength of innovation policies and their performance. Therefore, this paper would make a contribution to an evolution of governmental R&D support and an effective formulation of innovation policy.

Effects of Electroacupuncture on Parameters Related to Obesity in Adults with Abdominal Obesity:Three arm Randomized Single Blind Pilot Study (전침이 복부비만 성인의 비만관련 지표에 미치는 영향-무작위배정 단일 맹검 예비연구-)

  • Chung, Jie-Youn;Kim, Jong-In;Lee, Sang-Hoon;Kang, Sung-Keel
    • Journal of Acupuncture Research
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    • v.27 no.6
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    • pp.43-57
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    • 2010
  • Objectives : To investigate the effects of electroacupuncture on parameters related to obesity in adults with abdominal obesity. Methods : A three arm randomized single blind pilot study was conducted from Jan 4 to March 25, 2010 in Kyung Hee Oriental Medical Hospital. The subjects were 39 adults with abdominal obesity and were randomly divided by computer generated random table into 3 groups; EA(electroacupuncture), sham EA(sham electroacupuncture) and waitlist groups. Acupuncture points located at abdomen($CV_{12}$, $CV_6$, $ST_{25}$, $SP_{15}$, $SP_{14}$) and extremities($LI_4$, $LI_{11}$, $ST_{36}$, $ST_{44}$) were inserted by disposable stainless steel needles and were stimulated 30 minutes with 24Hz, 0.27~1.3mA(tolerable strength), asymmetric biphasic continuous pulse wave form by STN-111 Stratek device in EA group. Two treatment sessions per week for 5 weeks(10 sessions in total) were done in EA and sham EA groups. The primary outcome measurement was WC(waist circumference), and the secondary outcome measurements included WHR(waist hip ratio), ASF(thickness of abdominal subcutaneous fat), and inbody measurements of BW(body weight), BMI(body mass index), BFR(body fat ratio) and VFA(visceral fat area), and also scores of BULIT-R(bulimia test revised), KoQoL(Korean obesity of QoL) and BSQ(body shape questionnaire). Results : All of 39 subjects were included in ITT(intention-to-treat) analysis. There were significant reductions in WC, WHR and ASF after 5-week electroacupuncture treatments and the percentage reductions were significantly greater than sham EA or waitlist group. There were no significant differences between groups in percentage reductions of other parameters(BW, BMI, BFR, VFA, BULIT-R, KoQoL and BSQ). But, there were continuous reductions in BW, BMI, BFR and VFA at 3 weeks after the end of treatment and there was significant reduction in BW compared with the baseline value in EA group. No seriously adverse effects were reported during the period. Conclusions : Electroacupuncture was more effective than sham electroacupuncture or no intervention on the reduction of WC, WHR and ASF in adults with abdominal obesity.

Evaluation of Shear Zone in Direct Shear Test Using Elastic, Electromagnetic Waves and Cone Tip Resistance (전단파, 전자기파 및 콘 관입저항력을 이용한 직접전단실험시 전단영역 특성 평가)

  • Byun, Yong-Hoon;Truong, Q. Hung;Tran, M. Khoa;Lee, Jong-Sub
    • Journal of the Korean Geotechnical Society
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    • v.27 no.2
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    • pp.43-52
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    • 2011
  • The characteristics of shear zone in granular soils largely affect the stability of geo-structures. The goal of this study is to evaluate shear zone in a direct shear test using shear wave, electrical resistivity, and cone tip resistance. Bender elements and electrical resistivity probe are embedded into the wall of a direct shear box made of transparent acrylic material to estimate the shear wave velocities and the electrical resistivity at shear and non-shear zones. At the point of peak and residual strength, micro cone penetration test which can be available to measure tip resistance has been performed. Experimental results show that the shear wave velocities at upper shear zone increase during shearing while the values remain constant at bottom and lower shear zone. Also, resistivities at lower shear zone depend on relative density while resistivities at bottom remain constant. The results of cone penetration test demonstrate the correlation of the cone tip resistance and small strain shear modulus at shear zone. This study suggests that the application of the modified direct shear box including shear wave, electrical resistivity and the micro cone tip resistance may become effective tools for analyzing the characteristics of a shear zone.

Effect of Plant Growth Regulators, Media and Celling Agents on In Vitro Microtuber Production of Pinellia ternata Breit (1식물생장조절제, 배지와 고형지지물이 반하의 기내 소괴경 생산에 미치는 영향)

  • Kim, Yong-Kyung;Lee, Ji-Yeon;Kim, Eung-Hwi;Cho, Dong-Ha;Park, Sang-Un
    • Korean Journal of Medicinal Crop Science
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    • v.15 no.3
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    • pp.210-214
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    • 2007
  • The study was carried out to establish in vitro microtuber production from leaf and petiole explant cultures of Pinellia ternata. Culture conditions were optimized by investigating the effect of plant growth regulators, different media, and gelling agents on the efficiency of microtuber indurtion. Among the different combinations of plant growth regulators tested, the combination of 0.1 mg/l 2,4-Dichlorophenoxyacetic (2,4-D) and 0.5 mg/l 6-benzylaminopurine (BAP) showed the highest yield fer microtuber production from leaf (3.9) and petiole (4.7) explant culture on MS medium far 6 weeks. SH(Schenk and Hildebrandt) medium was the most effective medium for microtuber induction and the half strength SH medium was better than SH medium for microtuber production from both leaf and petiole culture. Gelrite was better than agar in the formation of microtubers and 4% Gelrite showed the highest number of microtubers per explant frome leaf (5.9) and petiole (7.8) culture. Germination rate of microtubers after cold storaged for one months long was 86% from in vitro culture and 43% from autoclaved soil.

Bond Behaviors of Epoxy Coated Reinforcements Using Direct Pull-out Test (직접 인발 시험을 이용한 에폭시 도막 철근의 부착 특성)

  • Kim, Jee-Sang;Lee, Sang-Hyun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.3
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    • pp.298-304
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    • 2017
  • The corrosion of reinforcements embedded in concrete causes some durability problems in reinforced and prestressed concrete structures. The epoxy coated reinforcements are one of the effective and reliable methods to prevent corrosion of reinforcements. However, it has been known that the epoxy coating reduces the bond capacity of reinforcement to concrete. This paper investigates the bond behaviors of epoxy coated reinforcements experimentally using direct pull-out test. Bond behaviors of epoxy coated bars for various reinforcement diameters of 10, 19 and 29mm and thicknesses of cover concrete of 1, 2, 3, and $4.5c/d_b$ (ratio of cover to bar diameter) are examined. Total 66 specimens were manufactured and tested according to the RILEM standard method. As the diameters of the epoxy coated reinforcements increase, the difference of bond strength between epoxy coated reinforcements and uncoated bars also increases. Epoxy coated bars showed more than 85% bond performance compared to those of uncoated bars. A new formular for estimating basic development length of epoxy coated reinforcement based on equilibrium equation is proposed using this experimental result.

Preparation and Characterization of PET/PVA-BA/OPP Multi-layer Films for Seasoned-laver Packaging (조미김 포장을 위한 PET/PVA-BA/OPP 다층필름 제조 및 특성분석)

  • Lim, Mijin;Kim, Dowan;Seo, Jongchul
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.23 no.1
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    • pp.9-15
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    • 2017
  • To identify applicability for packaging material of polyvinyl alcohol (PVA)/boric acid (BA) coating solution with highly-enhanced water vapor and oxygen barrier properties, the PET/PVA-BA/OPP multi-layer films were prepared through comma coating and lamination process. The oxygen and water vapor permeabilities, and tensile strength of as-prepared multi-layer films were investigated before and after pressure cooker test (PCT). Although oxygen and water vapor permeabilites, and mechanical properties of PET/PVA-BA/OPP multi-layer films was decreased after PCT, their properties were highly enhanced as increase of BA contents in PVA matrix. This is strongly related with enhanced cross-linking density in PVA-BA layer. In storage test of seasoned-laver, the PET/PVA-BA/OPP multi-layer films were comparatively effective to suppress the increase in peroxide value originating from oxidation of seasoned-laver. Comparing the commercially available PP/Al-metallized PP for seasoned-laver packaging, however, PET/PVA-BA/OPP multi-layer films did not show any advantage in water activity. This is due to higher water vapor permeation properties of as-prepared multi-layer films. Therefore, further studies are required to enhance the water vapor permeation in PET/PVA-BA/OPP multi-layer films.

Cyclic Loading Test for Composite Beam-Column Joints using Circular CEFT Columns (콘크리트피복 원형충전강관 기둥-강재보 접합부에 대한 반복하중실험)

  • Lee, Ho Jun;Park, Hong Gun;Choi, In Rak
    • Journal of Korean Society of Steel Construction
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    • v.29 no.6
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    • pp.411-422
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    • 2017
  • In this study, to investigate the seismic performance of beam-column joints using concrete-encased and -filled circular steel tube(CEFT) columns, two types of tests were performed: (1) column - flange tension test and (2) beam - column joint cyclic load test. In column - flange tension test, test parameters were concrete encasement and connection details: flange width and strengthening rebar. Five specimens were tested to investigate the load-carrying capacity and the failure mode. Test results showed that increase of flange width from 200mm to 350mm result in increase of connection strength and stiffness by 61% and 56%, respectively. Structural performances were further improved with addition of tensile rebars by 35% and 92%, respectively. In cyclic loading test, three exterior beam-column joints were prepared. Test parameters were strengthening details including additional tensile rebars, thickened steel tube, and vertical plate connection. In all joint specimens, flexural yielding of beam was occurred with limited damages in the connection regions. In particular, flexural capacity of beam-column joint was increased due to additional load transfer through tube - beam web connection. Also, connection details such as increase of tube thickness and using vertical plate connection were effective in improving the resistance of panel zone.

A Computer Graphics Program for 2-Dimensional Strut-tie Model Design of Concrete Members (콘크리트 구조부재의 2차원 스트럿-타이 모델 설계를 위한 컴퓨터 그래픽 프로그램)

  • Yun, Young Mook
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.37 no.3
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    • pp.531-539
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    • 2017
  • The strut-tie model approach has been recognized as an efficient methodology for the design of all types of concrete members with D-regions, and the approach has been accepted in design codes globally. However, the design of concrete members with the approach requires many iterative numerical structural analyses, numerous graphical calculations, enormous times and efforts, and designer's subjective decisions in terms of the development of appropriate strut-tie model, determination of required areas of struts and ties, and verification of strength conditions of struts and nodal zones. In this study, a computer graphics program, that enables the design of concrete members efficiently and professionally by overcoming the forementioned limitations of the strut-tie model approach, is developed. In the computer graphics program, the numerical programs that are essential in the strut-tie model analysis and design of concrete members including finite element analysis programs for the plane truss and solid problems with all kinds of boundary conditions, a program for automatic determination of effective strengths of struts and nodal zones, and a program for graphical verification of developed strut-tie model's appropriateness by displaying various geometrical shapes of struts and nodal zones, are loaded. Great efficiency and convenience during the application of the strut-tie model approach may be provided by the various graphics environment-based functions of the proposed program.

A study on the characteristics of tunnel deformation and support system according to tunnel portal reinforcement method (터널 갱구부 보강방법에 따른 터널 변형 및 지보재 응력특성에 관한 연구)

  • Moon, Kyoung-Sun;Seo, Yoon-Sic;Kang, Si-On;Kim, Sang-Hwan
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.20 no.3
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    • pp.625-639
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    • 2018
  • This study is about the reinforcing type of reinforcement method which is reinforced in tunnel portal of tunnel with bad ground condition. Generally, it is known that the horizontal reinforcement method is more effective than the conventional reinforcement method. However, as a limitation of the tunnel construction technology, it is being constructed by the superposition reinforcement method. In recent years, high-strength large-diameter steel pipes and horizontally oriented longitudes (L = 30.0~50.0 m) construction technology have been developed. Therefore, it is required to study reinforcement method of tunnel portal reinforcement method. Therefore, 3-D numerical analysis (Midas GTS NX 3D) was performed by setting the reinforcement method (No reinforcement type, overlap reinforcement type and horizontal reinforcement type) and ground condition as parameters. As a result, it was considered that the reinforcement effect was the largest as the horizontal reinforcement type of the reinforcement method was the smallest in the displacement and the support material stress. Based on the results of the numerical analysis, horizontal steel pipe grouting was applied to the actual tunnel site. The displacement of the tunnel portal and the stress of the support material occurred within the allowable values and were considered to ensure sufficient stability.

Effects of Intensive Pelvic Floor Muscle Exercise on Recovery of Genitourinary System, Sexual Life and Daily Life after Normal Delivery (골반근육강화훈련이 산후 비뇨생식기 회복, 성생활 및 일상생활 불편감에 미치는 효과)

  • Choi, Euy-Soon;Park, Chai-Soon;Lee, In-Sook;Oh, Jeong-Ah
    • Women's Health Nursing
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    • v.8 no.3
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    • pp.412-423
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    • 2002
  • This study was designed to evaluate the effect of pelvic floor muscle exercise using biofeedback and electrical stimulation after normal vaginal delivery. The data were collected from November 1999 to April 2000 at a university hospital located in Seoul, Korea. Out of 49 women with normal vaginal delivery, 25 of experimental group(with exercise) and 24 of control group(without exercise) were questioned about lower urinary symptoms, discomfort during sexual intercourse and daily life. The maximum pressure of pelvic floor muscle contraction(MPPFMC) and duration of pelvic floor muscle contraction(DPFMC) were measured at pre-treatment, the end of treatment and 8 weeks after a treatment program. The pelvic floor muscle exercise program(using biofeedback and electrical stimulation) was applied to the experimental group twice a week for 4 weeks at the incontinence clinic and the pelvic floor muscle exercise at home for that time and more 8 weeks. Data were analyzed by t-test, $x^2$-test, Fisher's exact test and the repeated measures ANOVA. The results were as follows; 1) MPPFMC(p=0.000) and DPFMC(p=0.021) were significantly increased in the experimental group. 2) In the lower urinary symptoms, daily frequency(p=0.001), nocturia(p=0.002), incontinence episode(p=0.016), stress incontinence(p=0.012), quantity of incontinence(p=0.026), straining(p=0.041), and strength of stream(p=0.009) were significantly decreased in the experimental group. 3) Discomfort during sexual intercourse had not a significant difference between the two groups, which was not significantly decreased as time passed. 4) In the discomfort during daily life, activity restriction(p=0.042), exercise restriction (p=0.008), interpersonal relationship restriction(p=0.046), and discomfort of general life(p=0.027) showed a significant difference between the two groups, which were not significantly decreased as time passed. In conclusion, it is suggested that the pelvic floor muscle exercise using biofeedback and electrical stimulation might be a safer and more effective program for the improvement of postpartum pelvic muscle contraction.

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