• Korean small business review
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• v.43 no.2
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• pp.31-57
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• 2021

This study delves into a question as to how the concept of corporate social responsibility (CSR) is internalized across corporations. CSR internalization refers to the process where a corporation incorporates CSR practices into its business practices. Drawn from the institutionalization process of knowledge adoption under environmental pressure, we pay attention to the roles of proximity, defined as the distance between environmental characteristics and organizational characteristics of corporations. And we argue that the extent to which a given firm is situated in the environment knowledgeable will make the firm likely to adopt CSR practices. To test this idea, we figure out when and how corporations participate in the B-Corporation Movement in the U.S., through the lens of proximity. Specifically, we subdivide proximity into geographical proximity, organizational proximity, and overlapped proximity and examine whether proximity can increase the likelihood of adopting CSR practices. With a sample of 536 start-ups which had participated in the B-Corporation Movement between 2007 and 2017, we find that the three types of proximity consistently increase the likelihood of becoming a certified B-Corp. This suggests that a corporation is highly likely to accept the concept of CSR under external pressures, along with its intrinsic motivation, which provide theoretical and practical implications on CSR internalization.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.5
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• pp.435-441
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• 2015

In this study, a method for optimal design of impeller and diffuser blades in the centrifugal compressor using response surface method (RSM) and multi-objective genetic algorithm (MOGA) was evaluated. A numerical simulation was conducted using ANSYS CFX with various values of impeller and diffuser parameters, which consist of leading edge (LE) angle, trailing edge (TE) angle, and blade thickness. Each of the parameters was divided into three levels. A total of 45 design points were planned using central composite design (CCD), which is one of the design of experiment (DOE) techniques. Response surfaces that were generated on the basis of the results of DOE were used to determine the optimal shape of impeller and diffuser blade. The entire process of optimization was conducted using ANSYS Design Xplorer (DX). Through the optimization, isentropic efficiency and pressure recovery coefficient, which are the main performance parameters of the centrifugal compressor, were increased by 0.3 and 5, respectively.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.6
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• pp.485-491
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• 2012

The wall interference effects around the wind-turbine airfoil are experimentally investigated at low Reynolds numbers in a closed test-section wind tunnel. The test is performed at free-stream velocities from 10 to 31 m/s, which correspond to Reynolds numbers ranging from $1.5{\times}10^5$ to $4.6{\times}10^5$ based on chord of the airfoil. The blockage-area ratios, which is the ratio of the chord to the test-section width, are 27.8%, 38.5%, 41.7%, 45.5%, and 55.6%. The test results for the airfoil show that the transition point on the airfoil surface tends to move backward due to wall interference. The wall pressures for an adequate interference correction by a measured-boundary-condition method are desirable more than three times region of the chord before and after around the reference center.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.2
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• pp.24-29
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• 1998

An experimental study was carried out to investigate the characteristics of spray pattern such as discharge coefficient, spray angle, and mass distribution for two-fluid airblast swirl injector, within the range of fluid supply pressure 0~13kg/$\textrm{cm}^2$. In general atomization is promoted with increasing total gas mass flow and performance of the splay pattern was more stable when radial mass flow was greater than axial mass flow, radial swirler was better than Axial swirler for atomization. Equivalent spray angle did not change with water mass flow except for the condition of 3kg/$\textrm{cm}^2$ and showed the same for the gas mass flow. Mass distribution from the patternator shows that maximum value of the distribution were lowered but distributed larger area when gas flow rate increased. Center of mass position did not change with increasing water mass flow.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.180-180
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• 2013

반도체, 디스플레이와 같이 저압, 극청정 조건에서 진행되는 공정에서 발생한 오염입자는 수 율에 큰 영향을 미친다. 따라서 공정 중에 발생한 오염입자를 실시간으로 모니터링할 수 있는 장비에 대한 연구가 활발히 진행되고 있다. Particle Beam Mass Spectrometer (PBMS)는 저압에서 실시간으로 나노 입자의 크기를 측정할 수 있는 대표적인 장비 중 하나이다. 입자를 포함한 가스 유동이 PBMS로 유입되면, 우선 입자를 입자빔의 형태로 집속하는 공기역학렌즈를 통과하게 된다. 집속된 입자는 노즐에 의해서 가속되며, 이로 인해 충분한 관성을 가지게 된 입자는 양극과 음극, 필라멘트로 구성된 electron gun에서 전자충돌에 의해 포화상태로 하전된다. 하전한 입자는 electrostatic deflector에서 크기에 따라 분류되어 Faraday detector와 electrometer에 의해 측정된다. 그러나 공기역학렌즈는 입자의 크기가 작아질수록 집속 효율이 급격히 낮아진다는 문제점을 지니고 있다. 이는 입자가 작아질수록 점성에 의한 영향이 관성에 의한 영향보다 커짐으로써 나타나는 현상이다. 최근 이러한 문제점을 해결하기 위해 사중극자를 사용하여 입자를 집속시키는 방법이 대안으로 제시되었다. 사중극자는 서로 마주보는 쌍곡선 형태의 전극구조에 AC 전기장을 인가하는 방식을 사용한다. 사중극자의 중심은 정확히 평형점을 가지게 되며 입자는 사중극자 내에서 진동을 반복하며 평형점을 향해 모이게 된다. 입자의 크기가 작을수록 전기력에 의한 영향을 크게 받으므로 사중극자를 이용한 입자집속 방법은 나노입자의 집속에 있어 공기역학렌즈를 이용한 집속에 비해 이점을 지닌다. 또한 집속 하고자 하는 입자 대상이 바뀔 경우 구조를 바꿔야 하는 공기역학렌즈와 달리 사중극자를 이용한 방법은 AC 전기장을 조절하는 것 만으로 제어가 가능하다. 본 연구에서는 저압 조건에서 나노입자를 집속하기 위한 사중극자의 전극 구조를 이론적인 계산을 통하여 구하였다. 그 결과 0.1 torr의 압력 조건하에서 5~100 nm 범위의 기본 입자를 AC 전압과 진동수를 조절하여 집속할 수 있는 사중극자 형태를 설계하였다.

• Journal of the Korean GEO-environmental Society
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• v.17 no.10
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• pp.23-31
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• 2016

Grout is generally operated with low viscous material similar to water, but grout for micro crack with high viscous materials and high injection pressure is gradually increased under the development of underground and subsea space. In order to estimate grouting injection performance considering crack width, viscosity of grouting materials, and injection pressure, there should be a reliable standard laboratory testing method. In this paper, theoretical injection mechanisms of grouting materials are presented as radial and linear flows, and laboratory testing apparatus are introduced to simulate each flow case. Radial flow is simulated by using acrylic disk plates which are able to spread grouting material radially from the center of the disk plates, and linear flow is simulated by using stainless parallel plane plates which are able to spread grouting material linearly. Apparatus are consist of upper and lower plates and industrial films with different thickness are placed between plates in order to simulate various crack widths. Laboratory verification tests with these apparatus were conducted with tap water (1cP at $20^{\circ}C$) as an injection material. Through the laboratory testing results, the best laboratory testing method is recommended in order to estimate grouting injection performance.

• Journal of Digital Convergence
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• v.15 no.6
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• pp.107-119
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• 2017

This article explores early childhood teachers' practices from bottom-up perspectives on the relationship between theory and practice. Results of the review of literature are as follows: 1) From top-down perspectives early childhood teachers' practices and their classroom behaviors have been traditionally defined within the framework of theories of child development, the notion of developmentally appropriate practice, and designed program models; 2) From bottom-up perspectives researchers have a focus on how teachers' practices lead theories and how they construct the act of teaching through reflective thinking; 3) empirical research on preservice and inservice teachers demonstrates that preservice teachers develop their own theories of teaching from their previously held assumptions, gained knowledge from preparation programs, and their individual experiences. It also shows that inservice teachers construct teaching through their implicit knowledge and the use of strategies to negotiate problems. Implications for future studies on teachers's practices are discussed.

• Physical Therapy Korea
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• v.22 no.3
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• pp.41-49
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• 2015

This study aimed to evaluate the surface area and velocity of center of pressure (COP) during one leg standing by stimulating the sensory system in normal adults. Thirty subjects were enrolled in this study. Subjects were asked to stand on one leg during testing conditions. Testing conditions included 6 different sensory stimulations as follows: eyes opened, eyes closed, eyes opened with vibrator, eyes opened with head-mounted display (HMD), eyes opened with vibrator and HMD, and eyes closed with vibrator. During each testing condition, the surface area and velocity of center of pressure were measured. There were significant differences in the mean surface area and the mean velocity of COP between the "eyes opened" condition and the other five testing conditions (p<.05). However, in the comparison between the "eyes closed" and "eyes opened with HMD" conditions, there were no significant differences in the tested parameters. This study shows that closing eyes or keeping eyes opened while using HMD to experience virtual reality has the same effect on one leg standing balance. This finding should be considered in the evaluation or intervention of balance, especially one leg standing balance and balance while standing with a small base of support.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.183-183
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• 2000

Aigrain에 의해 Helicon이라는 이름이 명명된 이후, helicon은 저온의 금속과 같은 높은 전도도(conductivity)를 갖는 매질이나 강한 자기장이 걸려있는 plasma를 전파해 나가는 저주파 전자기장을 지칭해왔다. 이온화된 개스에서 이러한 전자기장은 전자 공명 주파수(electron cyclotron frequency)와 이온 공명 주파수(ion cyclotron frequency) 사이의 주파수로 전파하며 전리층 (ionosphere)을 통과하며 발생하는 가청 주파수 영역대의 음조가 강하하는 현상에 의해 low-frequency whistler라고도 불린다. Helicon wave plasma는 Boswell에 의해 처음 발생된 후, 높은 이온화율(~100%)로 인해 많은 연구가 이루어져 왔다. 1985년에 Chen은 helicon plasma의 높은 이온화율을 설명하기 위해 Landaudamping을 제시하였다. 이러한 설명은 1997년에 Shamrai에 의해 TG mode가 도입되기 전까지 직접적인 실험결과 없이 helicon plasma 발생의 mechanism으로 받아들여졌다. shamrai의 이론에 의하면 정전기파(electrostatic wave)는 plasma의 표면(surface)에서 강하게 감쇄되어 energy를 전달하게 된다. Cho는 radial density 분포가 외각보다 중심이 높을 경우 TG wave의 power 전달이 중심에서 일어날 수 있음을 계산하였다. Helicon plasma의 특성은 높은 이온화율에 의한 높은 밀도($\geq$1012cm3), 1-2 kW의 rf power에서 상대적으로 낮은 전자 온도( 4eV), $\omega$ci $\omega$LH<$\omega$ $\omega$ce $\omega$pe 영역대의 주파수, 자기장 50-1200 Gauss, 압력 1-10 mTorr로 특정지을 수 있다. 이러한 외부분수들의 조건에 k라 helicon plasma는 여러 종류의 mode로 존재한다. Degeling은 이러한 mode의 변화를 capacitive mode, inductive mode, 그리고 helicon mode(wave mode)의 세가지 부분으로 구분하였다. Helicon plasma가 갖는 높은 이온화율은 여러 가지 응용으로의 가능성을 가지고 있다. 그 예로 plasma processing, plasma wave에 의한 입자 가속, 그리고 가스 레이저 활성 매질 발생 등이 있다. 특히 plasma processing의 경우 helicon plasma는 높은 밀도, 비교적 낮은 자기장, remote operation 등이 가능하다는 점에서 현재 연구가 활발히 진행되고 있다. 상업용으로도 PMT와 Lucas Signatone Corp.에 서 helicon source가 제작되었다. 또한 높은 해리율을 이용하여 저유전 물질인 SiOF의 증착에서 적용되고 있다. 이 외에도 다수의 연구결과들이 발표되었다.

• PNF and Movement
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• v.12 no.4
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• pp.201-207
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• 2014

Purpose: The purpose of this study was functional leg length inequality effect on COP(Center Of Pressure) and LOS(limits Of Stability) and EMG activation. Methods: The participants were consisted of fourteen. Subjects were distributed 2 groups; control group, leg length inequality ${\leq}3mm$, n=8), experimental group(leg length inequality${\geq}10mm$, n=8). The participants were measured leg length wearing comfortable clothes through tape measure method(TMM). All subjects was measured COP(Center Of Pressure), LOS(limits of stability) using by Balance Trainer BT4(HUR, Finland). Results: The results COP was not exist statistical significant differences(p>0.05). LOS was not exist statistical significant difference(p>0.05). Conclusion: The results was not statistical significant differences COP and LOS depending on Leg Length Inequality. But between experimental group and comparison group was exist mean differences on COP, LOS(COP:Ex.>Com, LOS:Ex.