• 제목/요약/키워드: External Effect

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전자.통신 분야에서 중소기업 규모에 따른 내.외부 혁신활동이 혁신성과에 미치는 영향에 관한 연구 (The Effect of Innovation Activities on Innovation Performance according to the size of SMEs in the Field of Electronics and Communication Industry)

  • 신선아;이문수
    • 산업경영시스템학회지
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    • 제37권1호
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    • pp.79-90
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    • 2014
  • The Purpose of this study is to empirically examine the impact of various internal and external innovation activities of SMEs on their innovation performances in the field of electronics and communication industry. Drawing upon the literature review, internal and external innovation activities are defined and conceptualized, and independent, dependent and moderator variables are developed. We have used survey-based data for this study from the survey of technology innovation activities in manufacturing industry, which was conducted by the Science and Technology Policy Institute (STEPI) in 2010. The main result of this study shows that there were no significant differences in the impact of innovation activities on market performance according to the size of SMEs. On the other hands, we found that there were significant differences in the impact of innovation activities on technological innovation performance according to the size of SMEs. Therefore, in order to make high technological innovation performance, companies in the field of electronics and communication industry need to properly implement the internal and external innovation activities by considering their size.

이동변형격자 기법을 활용한 외부장착물 분리운동 해석 (External Store Separation Analysis Using Moving and Deforming Mesh Method)

  • 안병희;김동현
    • 한국항공운항학회지
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    • 제27권4호
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    • pp.9-20
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    • 2019
  • A military aircraft generally includes external stores such as fuel tanks or external arming, depending on the purpose of the operation. When a store is dropped from a military aircraft at high subsonic, transonic, or supersonic speeds, the aerodynamic forces and moments acting on the store can be sufficient to send the store back into contact with the aircraft. This can cause damage to the aircraft and endanger the life of the crew. In this study, time accurate computational fluid dynamics (CFD) with dynamic moving grid (moving and deformable mesh, MDM) technique has been used to accurately calculate store trajectories. For the verification of the present numerical approach, a wind tunnel test model for the wing-pylon-finned store configuration has been considered and analyzed. The comparison results for the ejected store trajectories between the present numerical analysis and the wind tunnel test data at the Mach number of 0.95 and 1.2 are presented. It is also importantly shown that the numerical parameter of MDM technique gives significant effect for the calculated store trajectory in the low-supersonic flow such as Mach 1.2.

기후변화 대응 건축물 기화냉각시스템 적용에 따른 외부 열환경 변화 연구 (Changes in the External Heat Environment of Building Evaporative Cooling Systems in Response to Climate Change)

  • 윤용한;권기욱
    • 한국환경과학회지
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    • 제27권12호
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    • pp.1261-1269
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    • 2018
  • The purpose of this study was to investigate changes in the external thermal environment, following the application of evaporative cooling systems in buildings, in response to climate change. In order to verify changes in the external thermal environment, a T-test was performed on the microclimate, Thermal Comfort Index (TCI), and building surface temperature. Differences in microclimate, following the application of the evaporative cooling system in the building, were significant in terms of temperature and relative humidity. In particular, temperature decreased by more than 7% when the evaporative cooling system was applied. According to the results of the Thermal Comfort Index analysis, the Wet-Bulb Globe Temperature (WBGT) was below the limit of outdoor activities, indicating that outdoor activities were possible. The Universal Thermal Climate Index (UTCI) values were within the very strong heat stress range when the evaporative cooling system was not applied, When the system was applied, the UTCI values were within the strong heat stress range, indicating that they were lowered by one level. The building surface temperature decreased by ~10% or more when the evaporative cooling system was applied, compared to when it was not applied. Finally, the outside surface temperature of the building decreased by ~12% or more when the system was applied, compared to when it was not applied. We conclude that the energy saving effect of the building was significant.

PNF 하지굴곡패턴운동이 체간근육 활성도에 미치는 영향 (The Effects of PNF Leg Flexion Patterns on EMG Activity of the Trunk)

  • 김경환;기경일;윤혜진
    • PNF and Movement
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    • 제9권3호
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    • pp.19-24
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    • 2011
  • Purpose : The purpose of this study was to analyze the effect of PNF lower extremity flexion pattern on the eletromyographic (EMG) activity in rectus abdominis, internal oblique abdominal, external oblique abdominal, erector spinae. Methods : Twenty-six healthy adults volunteered to participate in this study. Subjects were required complete following two PNF lower extremity patterns; flexion-adduction-external rotation with knee flexion (D1) and flexion-abduction-internal rotation with knee flexion (D2). A paired t-test was used to determine the influence of the PNF two patterns on muscle activity for each muscle and descriptive statistics was used to determine local/global muscle ratio. Results : The D1 pattern was showed significant rectus abdominis (p<.05) and Median of internal oblique/rectus abdominis ratio was 2.23 and internal oblique/external oblique ratio was 1.53. The D2 pattern showed significant erector spinae (p<.05) and Median of internal oblique/rectus abdominis ratio was 3.06 and internal oblique/external oblique ratio was 1.72. Conclusion : The D1 pattern made rectus abdominis activation increase. The D2 pattern made erector spinae activation increase. As compared D1 and D2 pattern on trunk muscle activation, it's will be useful decision making for the trunk muscle strength and stabilization.

기계업종 중소기업의 생산성향상을 위한 외적지원효과에 관한 연구 (A Study on the Effect of External Support for Productivity Improvement of SMEs in Machinery Industry)

  • 구일섭;김태성
    • 한국경영공학회지
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    • 제23권4호
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    • pp.143-158
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    • 2018
  • It is also difficult for SMEs to pursue their own innovation activities due to their limited resources and capabilities. There are various government support policies for small and medium enterprises to enhance the competitiveness of the nation by improving sustainability management based on productivity improvement of SMEs. The purpose of this study is to investigate the factors that are important for the external support by the government and the related organizations in the machinery industry participating in the industrial innovation movement and identify the appropriate measures within and outside the organization. The results of this study are as follows: First, the higher the innovation commitment quality of the SMEs in the machinery industry, the more positive the non - financial performance. Second, the higher the quality of support from the headquarter, which has comprehensive responsibility for external support, the more positive the non - financial performance of participating companies. Third, it was concluded that the role quality of the consultant did not significantly affect the non - financial performance of participating companies in the machinery industry. Fourth, as the financial performance of the firm is better, the financial performance is also positively improved.

Seismic retrofit of steel buildings using external resistant RC walls and friction dampers

  • Mostoufi-Afshar, Pouya;Zahrai, Seyed Mehdi
    • Structural Engineering and Mechanics
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    • 제76권6호
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    • pp.823-837
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    • 2020
  • In this research, the idea of improving the seismic response of an existing steel structure with use of friction dampers between external walls and the structure is discussed. The main difference of this method with other methods of seismic rehabilitation is that interior spaces of the existing structure remain untouched and new parts including external walls and dampers are added outside of the structure. Three frames having 3, 6 and 9 stories are modeled in SAP2000 software before and after seismic retrofit and responses of the system are investigated under the effect of seven earthquake records. Initially, different ratios of seismic weight of stories are presumed for slip forces of the dampers with a distribution based on given equations. The optimized capacity of dampers is obtained by investigating the average of maximum displacement, acceleration and base shear of the structure caused by earthquakes. For this optimized values, maximum inter-story drifts and acceleration are obtained through numerical models. Results show that in 3, 6 and 9-story frames peak roof displacement decreased up to 80%. Maximum roof acceleration and base shear of the frames also decreased 46, 40 and 32% and 84, 67 and 65%, respectively for three building structures.

Evaluating performance of the post-tensioned tapered steel beams with shape memory alloy tendons

  • Hosseinnejad, Hossein;Lotfollahi-Yaghin, Mohammad Ali;Hosseinzadeh, Yousef;Maleki, Ahmad
    • Earthquakes and Structures
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    • 제23권3호
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    • pp.221-229
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    • 2022
  • The external post-tension technique is one of the best strengthening methods for reinforcement and improvement of the various steel structures and substructure components such as beams. In the present work, the load carrying capacity of the post-tensioned tapered steel beams with external shape memory alloy (SMA) tendons are studied. 3D nonlinear finite element method with ABAQUS software is used to determine the effects of the increase in the flexural strength, and the improvement of the load carrying capacity. The effect of the different parameters, such as geometrical characteristics and the post-tension force applied to the tendons are also studied in this research. The results reveal that the external post-tension with SMA tendons in comparison with the steel tendons causes a significant improvement of the loading capacity. According to this, using SMA tendon for the reinforcement of the tapered beams causes a decrease in weight of these structures and as a consequence causes economic benefits for their application. This method can be used extensively for steel beams due to low executive costs and simplicity of the operation for post-tension.

Influence of external structure and internal stacking on wind load characteristics of large-span spherical shell structure

  • Xiaobing Liu;Anjie Chen;Qun Yang;Bin Feng;Xuedong Tian
    • Wind and Structures
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    • 제39권3호
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    • pp.191-205
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    • 2024
  • To investigate the wind load characteristics of a large-span spherical shell structure, a rigid model pressure test was conducted in a wind tunnel laboratory. The study aimed to examine the impact of various external structures and internal stacking forms on the wind loads of a spherical shell structure in a practical engineering project. This project features two adjacent spherical structures, each spanning 130 m and standing 67 m tall. These two structures are connected by trestles and a transfer station. Variations in the shape factor and the integral force coefficient of the structure were compared and analyzed under different test cases. The results indicate that when two structures are arranged in series, with the adjacent structure positioned upstream, the shape factor of the structure is most affected, resulting in a significant reduction effect at the bottom of the windward surface. Compared to the external structure, the impact of various internal stacking forms on the shape factor of the structure is relatively weak. The adjacent structure significantly improves the wind resistance of the main structure. The integral force coefficient of the structure reaches its peak when internal stacking is full and is at its lowest when there is no internal stacking.

경증의 아토피 환자에서 한약 추출물 함유 외용제에 대한 임상 연구 (A Clinical Study for the Effect of External Applications Containing Herbal Extracts on Mild Atopic Dermatitis Patients)

  • 강민서;김정범;김희택
    • 한방안이비인후피부과학회지
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    • 제27권3호
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    • pp.40-55
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    • 2014
  • Objectives : The purpose of this study is to confirm the effects of external applications(CLANCHE SM A Clinic) containing herbal extracts on patient with atopic dermatitis. Methods : A total of 24 patients who visited Semyung Oriental Medical Center from January 15th, 2014 to February 20th, 2014 were included in the study. In this study, the patients were treated with external applications(CLANCHE SM A Clinic) containing herbal extracts. For 4 weeks of gross examination and instrumental assesment were made before and after the study. Results : 1. In the primary endpoint, SCORAD index showed a statistically significant decline. 2. In the secondary endpoint, index of skin hydration and index of TEWL showed statistical significance. 3. In the secondary endpoint, index of skin pH showed no statistically significant result. 4. To evaluate the safety of the products for the human body, vital sign check were conducted and showed no statistically significant result. And There were no severe adverse events during this study. Therefore, it is suggested that the safety of the products, if used for certain period, should be safe for the human body. 5. In global assesment of efficacy, both experimenter and subjects evaluated external applications were effective. Conclusions : According to the above experiments, it is suggested that external applications(CLANCHE SM A Clinic) containing herbal extracts should be effective for the atopic dermatitis.

외부구속자켓의 구속비와 강도비에 따른 콘크리트 부착거동의 특성 (Characteristics of Bond Behavior According to Confinement and Stiffness Ratios of External Confining Jackets)

  • 최은수;정춘성
    • 대한토목학회논문집
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    • 제34권1호
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    • pp.87-94
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    • 2014
  • 이 연구에서는 형상기억합금과 강재로 구속된 콘크리트의 부착응력을 외부자켓의 구속비 및 강도비를 이용하여 분석하였다. 이를 위해서 직경 1.0 mm 형상기억합금 와이어와 두께 1.0 mm와 1.5 mm 강판을 사용하여, 구속비 및 강도비의 차이를 유발하여 각 변수의 차이에 따른 부착강도 및 부착거동을 분석하였다. 외부자켓 구속에 의해서 콘크리트의 부착강도는 증가하였으며, 파괴형태도 쪼갬파괴에서 뽑힘파괴로 전환되어 구속효과가 있음을 알 수 있었다. 콘크리트 부착강도는 구속비와 강도비가 증가함에 따라 증가하는 현상을 보이지만, 특정 시점부터는 부착강도가 거의 증가하지 않고 일정한 값을 나타내는 결과를 보였다. 그러나 강도비의 증가에 따라 발생하는 원주방향 최대 변형율은 거의 선형적으로 감소하는 결과를 보였다.