• 한국통신학회논문지
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• 제26권11B호
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• pp.1540-1545
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• 2001

This paper is concerned with the reverse link performance of multi-code CDMA systems in multipath fading environments. The degree of orthogonality loss among multiple spreading code channels is characterized as the orthogonality factor. It depends on various system parameters including multipath power profiles of propagation channels and the number of Paths resolved at a Rake receiver. The effect of the parameters on the system performance is then investigated in terms of bit error rate and required signal quality. The results show that multipath delay power profiles dominantly affect mutual interference among multi-code channels and multipath combining gain by bandwidth expansion is not so great due to the increase of the mutual interference. Moreover, the orthogonality factor is derived as the value of between (1/m) and 1.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권3호
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• pp.186-190
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• 2000

It has been reported that flashing light enhances microalgal biomass productivity and overall photosynthetic efficiency. The algal growth kinetics and oxygen production rates under flashing light with various flashing frequencies (5Hz-37 kHz) were compared with those under equivalent continuous light in photobioreactors. A positive flashing light effect was observed with flashing frequencies over 1kHz. The oxygen production rate under conditions of flashing light was slightly higher than that under continuius ligth. The cells under the hight, particularly at higher cell concentrations. When 37kHz flashing light was applied to an LED-based photobioreactor, the concentration was higher than that obtained under continuous light by about 20%. Flashing light may be a reasonable solution to overcome mutual shading, particularly in high-density algal cultures.

• 대한기계학회논문집A
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• 제20권10호
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• pp.3048-3057
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• 1996

Analysis model containing two inclined surface cracks on semi-infinite elastic body is established and analyzed on the basis of linear fracture mechanics to examine mutual interference of two surface cracks. Muskhelishvili's complex stress functions are introduced and a set of singular integral equations is obtained for a dislocation density function. The stress intensity factors at crack tip are obtained by using the Gerasoulis'method. When two surface cracks are parallel and have the same length, the values of $K_1$and $\Delta K_11$(variation of $K_11$) for crack 1 and crack 2 decrease by the mutual interference of two surface cracks as the distance between the two surface cracks shortens. The effect of mutual interference is remarkable in high friction coefficient. In case that two surface cracks are parallel, the values of $K_1$and $\Delta K_11$for crack 2 decrease as the length ratio ot crack 2 to crack 1 becomes small. As the crack inclination angle rises, the value of $K_1$ and the mutual interference of $K_1$for crack 2 increase and the value of$\Delta K_11$ for crack 1 becomes smaller than that for crack 2.

• 천문학회보
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• 제42권2호
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• pp.48.3-49
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• 2017

Interplanetary space of the solar system contains a large number of dust particles, referred to as Interplanetary Dust Particles (IDPs) cloud complex. They are observable through meteors and zodiacal lights. The relative contribution of possible sources to the IDPs cloud complex was an controversial topic, however, recent research (Yang & Ishiguro, 2015 and references therein) suggested a dominance of cometary origin. In this study, we numerically investigated the orbital evolution of cometary dust particles, with special concerns on different evolutionary tracks and its consequences according to initial orbits, size and particle shape. The effect of dust particle density and initial size-frequency distribution (SFD) were not decisive in total cloud complex mass and mass supply rate, when these physical quantities are confined by observed zodiacal light brightness and dust particle SFD at 1 au. We noticed that, if we assume the existence of fluffy aggregates discovered in the Earth's stratosphere and the coma of 67P/Churyumov-Gerasimenko, the required mass supply rate decreases significantly. We also found out that close encounters with planets (mostly Jupiter) are the dominating factor of the orbital evolution of dust particles, as the result, the lifetime of cometary dust particles are shorter than Poynting-Robertson lifetime (around 250 thousand years). As another consequence of severe close encounters, only a small fraction of cometary dust particles can be transferred into the orbit < 1 au. This effect is significant for large size particles of ${\beta}$ < 0.01. The exceptional cases are dust particles ejected from 2P/Encke and active asteroids. Because they rarely encounter with Jupiter, most dust particles ejected from those objects are governed by Poynting-Robertson effect and well transferred into the orbits of small semimajor axis. In consideration of the above effects, we directly estimated probability of mutual collisions between dust particles and concluded that mutual collisions in the IDPs cloud complex is mostly ignorable, except for the case of large sized particles from active asteroids.

• 한국유통학회지:유통연구
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• 제13권2호
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• pp.79-95
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• 2008

본 연구는 쇼핑몰과 쇼핑몰에 입점한 테넌트를 연구의 대상으로 하고 있다. 쇼핑몰의 발전과 성장에 비해서 지금까지의 학문적 관심은 매우 제한적이었다. 본 연구에서는 기대-불일치 패러다임의 주요 변수인 기대, 성과, 불일치, 만족 및 재방문 의도를 쇼핑몰과 테넌트의 맥락에서 점검하고 있다. 특히 쇼핑몰과 테넌트간의 기대, 성과, 불일치, 만족 및 재방문 의도의 상호 영향을 중심으로 연구모형을 제시하였다. 가설은 기대불일치 관련변인을 쇼핑몰과 테넌트에 각각 적용하는 것에서 시작하여 쇼핑몰의 변수가 테넌트의 변수에 영향을 미치는 경우와 테넌트의 변수가 쇼핑몰의 변수에 영향을 미치는 경우로 확장하였다. 영향관계의 방향을 명확히 알 수 있는 경우와 이를 탐색해야 하는 부분으로 구분하여 고객의 쇼핑몰과 테넌트에 대한 상호 영향을 확인하였다. 461명의 몰인터셉트 서베이 결과 연구모형은 대체로 기대한 가설을 지지하는 것으로 나타났다. 방향성을 확인하는 가설에서는 테넌트에 대한 불일치와 만족이 쇼핑몰에 대한 불일치와 만족에 미치는 영향이 반대의 방향보다 유의적인 것으로 나타났으며 쇼핑몰에 대한 만족은 테넌트에 대한 재방문 의도에 미치는 유의적인 영향을 미치는 것으로 확인되있다.

• 한국의상디자인학회지
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• 제19권3호
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• pp.207-218
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• 2017

This study evaluates the difference in visual images according to changes in waist position and pants style. The researcher made twelve stimuli-combination of four pants styles (classic, baggy, skinny, bell-bottom) and three waist positions (0cm, -3cm, -5cm). The test involved 48 female college students. The stimuli were made using the i-Designer computer program. The panels tested the screen images of all manikins wearing pants. A 7-point scale was used to evaluate each image. For the data analysis, the ANOVA and Duncan-test were applied along with an SPSS program. The results of this study are as follows. The visual evaluations by pants style and waist position are composed of seven factors (attractiveness, attention, hip, activity, height, waist, abdomen). Among these factors, attractiveness is evaluated to be the most important factor. The mutual agreement of the visual effect (according to pants style and waist position) was indicated as four factors of attractiveness, attention, waist, and abdomen. The height factor is evaluated to be the most important factor by change in regards to waist position. The 0cm waist position of three styles (classic, baggy, bell-bottom) were evaluated positively in elongated height whereas the -3cm, -5cm waist position of the skinny style was evaluated positively in elongated height. The mutual agreements of visual effect (according to pants style and waist position) were not indicated.

• Journal of electromagnetic engineering and science
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• 제18권1호
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• pp.13-19
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• 2018

Wireless power transfer (WPT) based on magnetic resonant coupling is a promising technology in many industrial applications. Efficiency of the WPT system usually depends on the tilt angle of the transmitter or the receiver coil. This work analyzes the effect of the tilt angle on the efficiency of the WPT system with horizontal misalignment. The mutual inductance between two coils located at arbitrary positions with tilt angles is calculated using a numerical analysis based on the Neumann formula. The efficiency of the WPT system with a tilted coil is extracted using an equivalent circuit model with extracted mutual inductance. By analyzing the results, we propose an optimal tilt angle to maximize the efficiency of the WPT system. The best angle to maximize the efficiency depends on the radii of the two coils and their relative position. The calculated efficiencies versus the tilt angle for various WPT cases, which change the radius of RX ($r_2=0.075m$, 0.1 m, 0.15 m) and the horizontal distance (y=0 m, 0.05 m, 0.1 m), are compared with the experimental results. The analytically extracted efficiencies and the extracted optimal tilt angles agree well with those of the experimental results.

• 지식경영연구
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• 제13권2호
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• pp.53-72
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• 2012

Recently, an effective building and utilization of information system are essential in franchise firms as well as corporate management. Accordingly, this study is to examine the structural relationships among partnership quality of supplier, trust with a supplier and commitment, and franchise information system performance based on Henderson's(1990) information system partnership model and Lee and Kim's(1999) partnership model. For these purposes, the authors developed several hypotheses. The data were collected from 173 franchisors and analyzed with SPSS 18.0 and AMOS 18.0 The results are as following. First, sharing knowledge, interdependence, and mutual benefit influence supplier trust, but do not influence commitment. Second, supplier trust affect commitment and it prove that supplier trust is a full mediating role between partnership quality and commitment of franchise and information system supplier. Third, both supplier trust and commitment have a positive effect on performance of franchise information system. Therefore, it implies that supplier trust is significant factor in an performance of franchise information system. At the end of this paper, managerial and theoretical implications, limitations and future research directions were suggested.

• 대한가정학회지
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• 제46권10호
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• pp.83-96
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• 2008

Using a sample of 107 married couples, this study investigated the influence of self-reported argument-communication behaviors on marital satisfaction. The results were as follows. (a) Wives used more criticism, contempt, and self-assertion during marital arguments than husbands. There were no significant gender differences in the levels of defensiveness, stonewalling, and active listening. (b) Multilevel analyses indicated that marital satisfaction was predicted by the person's own level of self-assertion and stonewalling(i.e., actor effects) and by his or her spouse's level of stonewalling(i.e., partner effect). No other significant actor and partner effects were found. Also, there were no significant gender differences in the sizes of effects. (c) A cluster analysis of both spouses' communication behaviors during marital arguments identified four distinct groups of married couples. : mutual constructive, husband constructive-wife destructive, husband destructive-wife constructive, and mutual destructive. Mutual constructive couples reported the best marital satisfaction.

• 산경연구논집
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• 제9권1호
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• pp.9-23
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• 2018

Purpose - The purpose of this paper is to investigate the potential benefits or detriments of team management on fund performance in the mutual fund market. An additional purpose of this study is to examine the optimal number of managers in a fund industry for superior performance. Research design, data, and methodology - This paper investigates the effect of managerial structure on fund performance in the Korean active mutual fund market between 2001 and 2008. For this, we analyze two risk-adjusted performances measures- the capital asset pricing model (CAPM) and the three-factor model of Fama & French (1993). Results - First, we found that single-managed funds exhibited superior performance. Second major finding was that as the number of managers in a fund increases, the fund performance deteriorates. Finally, the results reveal that the sharpest performance drop occurs when team size increases from a 5-person team to a 6-person team. Conclusions - The results suggest that the management structure can be a source of competitive advantage for fund performance. As considering fund performance is the outcome of managers' decision-making, this study contributes to not only the financial literature but also the literature in other areas, such as management and general business.