• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.8C
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• pp.1086-1103
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• 2004

Most research efforts on the OCDMA technology assume single-bit-per-symbol transmission techniques such as on-off keying. However, achieving high spectral efficiency with such transmission techniques is likely to be a challenging task due to the "unipolar" nature of optical signals. In this paper, an M-ary transmission technique using more than two equally-weighted codes is proposed for OCDMA local area networks, and ie BER performance and spectral efficiency are analyzed. Poison frame arrival and randomly generated codes are assumed for the BER analysis, and the probability of incorrect symbol detection is analytically derived. From the approximation, it is found that there exists an optimal code weight that minimizes the BER, and its physical interpretation is drawn in an intuitive and simple statement. Under the assumption of this optimized code weight and sufficiently large code dimension, it is also shown that the spectral efficiency of OCDMA networks can be significantly improved by increasing the number (M) of symbols used. Since the cost of OCDMA transceivers is expected to increase with the code dimension, we finally provide a guideline to determine the optimal number of symbols for a given code dimension and traffic load.

• The Research Journal of the Costume Culture
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• v.12 no.2
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• pp.199-210
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• 2004

This study was intended to identify the differences in perception of image words and perception dimension of desired image according to sex variable for college students in a school context. Data were collected by questionnaires distributed to 443 college students from August to September of 2000. After eliminating incomplete questionnaires, 396 were analyzed. As results of factor analysis, 7 desired image factors were determined for male and female, respectively. On the basis of these results, major perception differences were identified according to sex variable. Differently-perceived image words were as fellows: For intellectual image, male relates it with sporty while female relates it with graceful; for masculine image, male relates it with mature while female relates it with sporty; and for feminine image, male relates it with sexy and graceful while female relates it modest, pure, and cute. Multidimensional scaling was employed to determine the perception dimension of desired image. Two dimensions were accepted to interpret the results for both sex, respectively. 'Feminine-masculine' and 'conspicuous-plain' were criteria for male students, while 'unnatural-natural' and 'feminine-masculine' were criteria for female students.

• International Commerce and Information Review
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• v.8 no.2
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• pp.37-58
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• 2006

The purpose of this study were to empirically examine the effect of dimension of service quality of internet shopping mall on quality of customer relationship(customer satisfaction) and Relationship of between Future Intention. This study first extracted environment, general interaction between customer and internet shopping mall, personalized interaction between customer and internet shopping mall, interaction between customers and outcome from service quality of internet shopping mall. Then established study model and hypotheses through the review of the effect of service quality of internet shopping mall on quality of customer relationship. and the effect of customer relationship quality on future intention. The results were as follows: At among of the six hypotheses, four hypotheses were accepted and two hypotheses were rejected First, for the relationship between dimensions of service quality of internet shopping mall and Customers satisfaction, only the environment had not significant influence on Customers satisfaction, other dimensions had significant positive influence on satisfaction. second, for the relationship between quality factors of customer relationship and future intention, only Customers satisfaction had not significant influence on future intention.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.2
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• pp.173-180
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• 2003

Effects of the electric conductivity of particles were studied for the aggregation process of charged particles with a Brownian dynamic simulation in the free molecular regime. A periodic boundary condition was used for the calculation of the aggregation process in each cell with 500 primary particles of 16 nm in diameter. We considered two extreme cases, a perfect conductor and a perfect nonconductor. The electrostatic force on a particle in the simulation cell was considered as a sum of electrostatic forces from other particles in the original cell and its replicate cells. We assumed that aggregates were only charged with pre-charged primary particles. The morphological shape of aggregates was described in terms of the fractal dimension. The fractal dimension for the uncharged aggregate was D$_{f}$= 1.761. However, the fractal dimension decreased from 1.694 to 1.360 for the case of the perfect conductor, and from 1.610 to 1.476 for the case of the perfect nonconductor, with the increase of the average number of charges on the primary particle from 0.2 to 0.3. These values were smaller than that of the centered charge case.e.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.5
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• pp.445-453
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• 2001

The multiple targets tracking problem has been one of the main issues in the radar applications area in the last decade. Besides the standard Kalman filtering, various methods including the variable dimen-sion filter, input estimation filter, interacting multiple model(IMM) filter, dederated variable dimension filter with input estimation, etc., have proposed to address the tracking and sensor fusion issues. In this pa- per, two existing tracking algorithm, i.e, the IMM filter and the variable dimension filter with input estima-tion(VDIE), are combined for the purpose of improving the tracking performance for maneuvering targets. To evaluate the tracking performance of the proposed algorithm, three typical maneuvering patterns, i.e., waver, pop-up, and high-diver motions, are defined and are applied to the modified IMM filter as well as the standard IMM filter. The smaller RMS tracking errors, in position and velocity, of the modified IMM filter than the standard IMM filter are demonstrated though computer simulations.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.6
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• pp.700-711
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• 2011

The purposes of the study were to identify the online service attributes that contribute to online consumer experiences of satisfaction, service failure, and service recovery and to examine whether differences exist in these attributes between U.S. and Korea. E-A-S-QUAL provided a useful framework for the study. Focus group interviews and web surveys were conducted by utilizing college students in both countries. No significant cultural differences were found in online service dimensions of service satisfaction. Personalization was the most frequently mentioned online service dimension of service satisfaction both in the U.S. and Korea. The findings showed significant cultural differences in terms of online service dimensions responsible for service failure and recovery. For Korean consumers, merchandising was one of the key online service dimensions of service failure, while efficiency was the important service dimension resulting in service failure for the U.S. consumers. In addition, for U.S. consumers, efficiency and personalization were the two most frequently mentioned service dimension for service recovery, while Korean consumers put more importance on the contact and information dimensions for service recovery. This study provided a comprehensive list of online service attributes important to online apparel retailing.

• ETRI Journal
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• v.27 no.2
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• pp.188-194
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• 2005

We report on the improvement of critical dimension (CD) linearity on a photomask by applying the concept of process proximity correction to a laser lithographic process used for the fabrication of photomasks. Rule-based laser process proximity correction (LPC) was performed using an automated optical proximity correction tool and we obtained dramatic improvement of CD linearity on a photomask. A study on model-based LPC was executed using a two-Gaussian kernel function and we extracted model parameters for the laser lithographic process by fitting the model-predicted CD linearity data with measured ones. Model-predicted bias values of isolated space (I/S), arrayed contact (A/C) and isolated contact (I/C) were in good agreement with those obtained by the nonlinear curve-fitting method used for the rule-based LPC.

• The korean journal of orthodontics
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• v.17 no.1
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• pp.63-72
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• 1987

This is to investigate the difference between craniofacial correlation of Angle's class III malocclusion and that of normal occlusion. For this investigation, 28 adult males and famales, who have class III malocclusion, and 35 adult males and 46 adult famals., who have normal occlusion were selected to measure actual dimension of cranial base and to investigate ratio of various parts of maxillofacial skeleton against cranial base. Class III malocclusion were, also , classified based on SNA and SNB angle in normal range. Results were as follows. 1. In class III malocclusion, actual dimension of cranial base were appeared to be less than normal occlusion in both sex. 2. In class III malocclusion, values were less than normal occlusion in BN/ptm-A in both sex, but had no significance between two. 3. In class III malocclusion, ramal inclination, mandible inclination, BN/Go-Pog, lower genial angle were appeared to be greater. Thus, characteristic mandibular protrusive appearance of class III malocclusion was due to relative ratio and morphologic characteristic of mandibular body dimension against cranial base. 4. In class III malocclusion, upper incisors were labially tilted and lower incisors were lingually tilted compared to normal occlusion. 5. In typing of class III malocclusion, the most common type was found to be one which maxillas were in normal range, while mandibles were in protrusive tendency.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.6
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• pp.543-551
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• 2015

In this study, a novel method for dimension measurement of large-scale moving objects using stereo camera with 2-degree of freedom (2-DOF) mechanism is presented. The proposed method utilizes both the advantages of stereo vision technique and the enlarged visibility range of camera due to 2-DOF rotary mechanism in measuring large-scale moving objects. The measurement system employs a stereo camera combined with a 2-DOF rotary mechanism that allows capturing separate corners of the measured object. The measuring algorithm consists of two main stages. First, three-dimensional (3-D) positions of the corners of the measured object are determined based on stereo vision algorithms. Then, using the rotary angles of the 2-DOF mechanism the dimensions of the measured object are calculated via coordinate transformation. The proposed system can measure the dimensions of moving objects with relatively slow and steady speed. We showed that the proposed system guarantees high measuring accuracy with some experiments.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.3
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• pp.417-427
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• 1998

Price, one of the marketing 4p's, is a key decision variable affecting market share and the profitability of individual products. For consumers, since price is almost always known to and can be compared, it is one of the most important criteria when they make a purchase decision making. With the consumers' increasing consciousness for price due to economic recession, and the saturation of domestic apparel market, it is expected that the effect of price on consumers' decision making would be greater than ever. This study, the first in two part series, focuses on testing the validity of dimensions of clothing price using Lichtenstein et. at. (1993)'s suggestion. In addition, the effect of demographic variables on the perception of each price dimension was investigated. The subjects were 264 college students living in Seoul, Korea. The data were collected by self -administered questionnaires and analyzed by t-test, ANOVA, regression analysis and Lisrel confirmatory factor analysis. The result supported Lichtenstein et. al. (1993)'s suggestion. That is, consumers' perception of clothing price is not mini-dimensional, but has six dimensions: sale proneness, price mavenism, value consciousness, price consciousness, price -quality schema and prestige sensitivity. Demographic variables partially effect on the consumers' perception of each clothing price dimension. The level of monthly pocket money, however, has influence on all price dimensions. Based on these results, marketing implications for apparel manufacturers were suggested.