• Journal of the Microelectronics and Packaging Society
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• v.31 no.3
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• pp.67-71
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• 2024

A smart window based on a retarder can transmit or block polarized lights by overlapping two smart windows. In the study, tests were conducted to evaluate the performance of blocking solar heat using smart windows with a size of 300×300 mm². Solar heat gain coefficient (SHGC) values were derived through simulation using transmission and reflectance data of the smart windows. As a result of the simulation, it showed that SGHC is effective in blocking solar heat by obtaining values of 0.722 and 0.615 in transmission and blocking mode of smart windows, respectively. The test boxes were fabricated in order to verify the effect of suppressing temperature rise when applying smart windows, the inside temperature in test boxes, which are installed bare glass (reference) and two smart windows with transmission and blocking mode, were measured at 10 minutes-interval for 7 days. As of 1 p.m., the inside temperature of the test boxes with the smart windows applied showed lower temperature compared to the reference. In particular, on the day when the temperature of reference box was the highest at 66.1℃, the temperature of the test box with the smart window applied showed 61.0℃, which was lowered by 5.1℃.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.3
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• pp.1-13
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• 2015

Strong ties such as family members, relatives and close friends have been widely acknowledged as a vital factor when a potential entrepreneur attempts to initiate entrepreneurial activity. Recent theoretical arguments focus that family social capital, a form of social capital, that is embedded in family relationships can contribute to venture creation as well as to the development of competitive advantage for established firms. Meantime, there have been arguments that the most dominant single entrepreneurial ethnic group in the world is the Chinese people, while the People's Republic of China is widely recognized as fast growing economic power that is driven by entrepreneurial ventures in a large scale. This study tests the effect of perceived relational supports typically being provided by family members, close relatives and friends on forming self-efficacy and entrepreneurial motivation of university students by using samples collected from 4 Korean Universities(Wonkwang, Baekseok, Soongsil and Dankook university) and Guangzhou University in China. The mediating of self-efficacy was also tested to gain better understanding of the role of the variable. The results of the study suggest that 1) both self-efficacy and entrepreneurial motivation are influenced positively by the perceived relational supports, 2) self-efficacy of university students affects their entrepreneurial motivation positively, 3) self-efficacy is appeared to be mediated partially for China in between perceived relational supports and entrepreneurial motivation, but the same variable is exhibited a full mediation in the same path of the research model for Korea, which was a distinction between the students of two countries in this study. Discussion and practical implication on the results are provided.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.5
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• pp.1325-1341
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• 1998

A conventional CBR channel is now capable of delivering several digitally compressed video programs due to recent advances in video compression, such as MPEG-2, and digital transmission technology. This paper presents a joint video coding scheme that is to maintain a constant sum of bit rates for all the programs but to allow the variable bit rate for individual program in the transimission environment mentioned above. Thus advantages of VBR video compression can be obtained. This paper contributes in two aspects. First, a rate-distortion estimation method for MPEG-2 video is proposed, which enavle us predict the amount of bits and the distortion generated from an encoded picture at a given quantization step size and vice versa. The most attractive features of the proposed rate-distortion estimation method are its accuracy and a computational complexity low enough to be applied to real-time video coding applications. Second, this paper presents an efficient and accurate joint rate control scheme using the rate-distortion estimation results and verifies its performance with experiments. The experimental results show that our coding scheme gives a significant gain even though a small number of video programs are coded jointly. For example, a stable picture quality is maintained among the video programs as well as within a program, and additional extra programs can be transmitted over the same channel bandwidth if the proposed joint video coding scheme is used.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.3
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• pp.68-76
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• 2000

The stabilization control of Inverted Pendulum(IP) system is difficult because of its nonlinearity and structural unstability. Futhermore, a series of conventional techniques such as the pole placement and the optimal control based on the local linearizations have narrow stabilizable regions. At the same time, the fine tunings of their gain parameters are also troublesome. Thus, in this paper, an Evolving Neural Network Controller(ENNC) which its structure and its connection weights are optimized simultaneously by Real Variable Elitist Genetic Algorithm(RVEGA) was presented for stabilization of an IP system with nonlinearity. This proposed ENNC was described by a simple genetic chromosome. And the deletion of neuron, the according to the various flag types. Therefore, the connection weights, its structure and the neuron types in the given ENNC can be optimized by the proposed evolution strategy. And the proposed ENNC was implemented successfully on the ADA-2310 data acquisition board and the 80586 microprocessor in order to stabilize the IP system. Through the simulation and experimental results, we showed that the finally acquired optimal ENNC was very useful in the stabilization control of IP system.

• 한국벤처창업학회:학술대회논문집
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• 2007.04a
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• pp.203-226
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• 2007

The purpose of this research is to analyze the impact of business scope and technological innovation capability(TIC) on firm performance in SMEs. Among the 1,077 SME sample data collected with the help of Korean Industrial Complex Corporation, 228 sample data from capital goods sectors had been selected and analyzed. Several mutiple regression models were developed to test the main and the interaction effects of two independent variables business scope and TIC on SME performance. The empirical analysis show that the number of product lines, one of the two scope variable measured, is positively correlated with the return on sales(ROS). Among the variable of TIC, the number of intellectual property rights(IPRs) is positively correlated with the sales growth rates of SMEs, which the ratio of engineers to total employees is positively correlated with the ROS of SMEs. The results also delineated some interaction effects of business scope and TIC on SME performance. There exists a positive interaction effect of the ratio of engineers to total employees and the number of product lines both on ROS and scales growth rate. The interaction of the number of customers and the number of IPRs positively effects on ROS, and also the interaction of the number of product lines and the number of IPRs are positively related with ROS. Findings of this research indicates that it is necessary for SMEs in capital goods sectors to accumulate technological innovation capability and to expand business scope to improve firm performance. Furthermore, the accumulation of internal TIC should accommodate with the expansion of business scope to gain an improved performance. Particularly, adequate technological innovation capability is required to address the need of expanded customers when enlarging the scope of customers.

• Journal of Nutrition and Health
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• v.33 no.2
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• pp.193-201
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• 2000

This study was conducted to investigate the effectiveness of nutrition counseling on the dietary intake and nutritional status cancer patients undergoing radiotherapy treatment. The study was conducted over 6 week period and included 104 patients : 66 received nutrition counseling as the variable group of 42 male and 24 female and 38 patients received no counseling as the control group of 19 male and 19 female. Nutrition counseling was accompanied with the radiation therapy and adminstered via counseling session and distribution of printed material during radiation therapy for 6 weeks. Nutrition counseling aimed at maintaining a balanced diet and preventing weight loss of subjects, guideline used for energy and protein intake were 35kcal/kg IBW and 1.5-2.0g/kg IBW, respectively. Over the course of the study, the counseling group increased significantly in comparison to the control group's energy intake, evidenced by the counseling group's initial mean daily energy intake of 1932.0kcal, and 4 and 6 week mean energy intake values of 2046.6kcal, 2066kcal, respectively. But mean energy values of control group was 1614.3kcal at 4 week. Th energy intake per weight values and protein intake per weight values for initial, 4 and 6 week intervals for counseling group were 33.2kcal/kg, 33.7kcal/kg, 34.0kcal/kg, and 1.48g/kg, 1.58g/kg, 1.59g/kg, respectively. Based on results, nutrition counseling had positive effects on both the variety of diet and energy intake of the variable group, mostly due to an increase in dairy product and egg consumption. In addition, the percentage of counseling group patients who consumed all 5 food group increased from 48.5% to 54.5%. Sufficient energy intake and protein consumption seem to be important factors in weight loss prevention, evidenced by weight gain by subjects in the counseling group who had 36.1kcal/kg/day mean energy intake and 1.77g/kg/day mean protein intake after 4 weeks. Counseling group subjects experiencing weight loss had lower intake and 1.77g/kg/day mean protein intake after 3 weeks. Counseling group subjects experiencing weight loss had lower intakes of 29.3kcal/kg/day for energy and 1.33g/kg/day for protein during the same period. Another significant factor in weight loss prevention of the counseling group could be the variety of diet. The dietary variety scores(DVS) of both counseling and control groups differed significantly : the counseling group had a mean score of 34 while the control group of patients. At the end of the study, the mean percentage of subjects within each group having a DDS 5 was higher in the counseling group (54.5% v.s. 24.0%). In this study, nutrition counseling for cancer patients undergoing radiation therapy proved to be effective in preventing weight loss, a major complication during radiotherapy. Nutrition counseling not only increased protein and energy intake, but also had desirable effects on variety or diversity of diet.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.2
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• pp.74-85
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• 2012

As competition increases, ski resort managers need to search for ways to attract previous visitors or to gain new visitors through word-of-mouth. This study examined the impact of skiers' perceived value, satisfaction and self-congruity on the revisit intention and the positive word-af-mouth intention. Total respondents were also segmented into a promotion-focus and prevention-focus individuals then later examined the differences in the effect of independent variables between groups in order to suggest a managerial direction that will enhance business competency of ski resorts. Results from regression analysis showed that all independent variables utilized in this study were good predictors of two dependent variables. Specially, satisfaction was a highly significant predictor. Promotion and prevention-focused individuals were also differed in evaluating the importance of independent variables for their revisit and word-of-mouth intention. It means that self-regulatory focus is an effective variable for segmentation. More specifically, satisfaction was the only variable influencing the revisit intention for promotion-focused individuals; whereas both satisfaction and self-congruity had significant effects on the revisit intention for prevention-focused individuals. All independent variables had significant effects on the word-of-mouth intention, except self-congruity for promotion-focused individuals. This research suggests several managerial implications on the findings based on the analysis and the characteristics of the visitors.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.3
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• pp.1059-1065
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• 2010

Very-early strength latex-modified concrete (VES-LMC) was developed for the purpose of fast-track overlay of a concrete bridge deck under heavy traffic, concentrated on the workability, durability, and strength gain so that it can be opened to the traffic only three hours after its placement. The mixture of VES-LMC might accompany very high heat of hydration at early-age because of its inherent rapid hardening property and could have susceptibility to autogenous shrinkage because of its relatively low water-cement ratio. This study evaluated the effect of the latex-cement ratio(L/C) both of the constant and variable slumps on the autogenous shrinkage of VES-LMC by carrying out simple temperature rise test and early-age shrinkage experiment. Test results are as follows: The latex contributes on the enhancement of the concrete durability but has little effect on its hydration and the accompanied heat of hydration in VES-LMC. Autogenous shrinkage increased with the increase in latex-cement ratio at variable slumps and its pattern followed regularly a logarithmic increase. However, the influence of water-cement ratio and latex-cement ratios for the test specimens at constant slump on early-age autogenous shrinkage property was found to be minor due to the simultaneous effect of the two experimental variables.

• ETRI Journal
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• v.26 no.3
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• pp.229-240
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• 2004

This paper reports on our development of a dual-mode transceiver for a CMOS high-rate Bluetooth system-onchip solution. The transceiver includes most of the radio building blocks such as an active complex filter, a Gaussian frequency shift keying (GFSK) demodulator, a variable gain amplifier (VGA), a dc offset cancellation circuit, a quadrature local oscillator (LO) generator, and an RF front-end. It is designed for both the normal-rate Bluetooth with an instantaneous bit rate of 1 Mb/s and the high-rate Bluetooth of up to 12 Mb/s. The receiver employs a dualconversion combined with a baseband dual-path architecture for resolving many problems such as flicker noise, dc offset, and power consumption of the dual-mode system. The transceiver requires none of the external image-rejection and intermediate frequency (IF) channel filters by using an LO of 1.6 GHz and the fifth order onchip filters. The chip is fabricated on a $6.5-mm^{2}$ die using a standard $0.25-{\mu}m$ CMOS technology. Experimental results show an in-band image-rejection ratio of 40 dB, an IIP3 of -5 dBm, and a sensitivity of -77 dBm for the Bluetooth mode when the losses from the external components are compensated. It consumes 42 mA in receive ${\pi}/4-diffrential$ quadrature phase-shift keying $({\pi}/4-DQPSK)$ mode of 8 Mb/s, 35 mA in receive GFSK mode of 1 Mb/s, and 32 mA in transmit mode from a 2.5-V supply. These results indicate that the architecture and circuits are adaptable to the implementation of a low-cost, multi-mode, high-speed wireless personal area network.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.8-12
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• 2005

Response in a modified reciprocal recurrent selection scheme for egg production was evaluated considering variable family sizes and genetic correlation between purebred and crossbred half sisters. The criteria of selection of purebred breeders included pullet's own performance, purebred full and half sisters and crossbred half sister's performance. Heritability of egg production of crossbreds (aggregate genotype) and purebred's was assumed to be 0.2 and genetic correlation between purebred and crossbred half sisters ($r_{pc}$) as 0.1, 0.2, 0.3, 0.4, 0.5, 1.0, -0.1, -0.2, -0.3, -0.4, -0.5 and -1.0. Number of dams per sire to produce purebred and crossbred progenies assumed to be 5, 6, 7, 8, while number of purebred female progeny ($N_p$) and crossbred progeny ($N_c$) per dam were considered to be 3, 4, 5 and 6 in each case. Considering phenotypic variance as unity, selection indices were constructed for different combinations of dams and progeny for each value of $r_{pc}$. Following selection index theory, response in crossbred and purebred for egg production was computed. Results indicated that response in crossbreds depended mainly on crossbred family size and also on magnitude of$r_{pc}$ irrespective of its direction, and response was greater with large crossbred family size than the purebred families. Correlated response in purebreds depends both on magnitude and direction of $r_{pc}$ and was expected to be greater with large purebred family size only. Inclusion of purebred information increased the accuracy of selection for crossbred response for higher magnitude of$r_{pc}$ irrespective of its direction. Present results indicate that desirable response in both crossbred and purebred performance is a function of $r_{pc}$ and family sizes. The ratio of crossbred and purebred family sizes can be optimized depending on the objective of improving the performance of crossbreds and/or of purebreds.