• Journal of the Society of Naval Architects of Korea
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• v.44 no.2 s.152
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• pp.198-209
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• 2007

In this paper, we present the gouging and collision-free tool-path generation for manufacturing model propellers using the 5-axis NC machine. Because it takes much time to generate tool-paths when we use general purpose CAD/CAM systems, a specific system would be necessary for marine propellers. Overall manufacturing process is composed of two steps: roughcut and finishcut steps. The roughcut is conducted using only 3-axis for efficient machining and the finishcut is done using 5-axis for avoiding collision. The tool-path that might happen to gouging is searched and the tool position is also decided for avoiding interference between the tool and the propeller blades. The present algorithm is applied extensively to the surface piercing propellers. Some results are demonstrated for its validation.

• Journal of information and communication convergence engineering
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• v.13 no.1
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• pp.7-14
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• 2015

In a multi-hop wireless network, connectivity is determined by the link that is established by the receiving signal strength computed by subtracting the path loss from the transmission power. Two path loss models are commonly used in research, namely two-ray ground and shadow fading, which determine the receiving signal strength and affect the link quality. Link quality is one of the key factors that affect network performance. In general, network performance improves with better link quality in a wireless network. In this study, we measure the network connectivity and performance in a shadow fading path loss model, and our observation shows that both are severely degraded in this path loss model. To improve network performance, we propose power control schemes utilizing link quality to identify the set of nodes required to adjust the transmission power in order to improve the network throughput in both homogeneous and heterogeneous multi-hop wireless networks. Numerical studies to evaluate the proposed schemes are presented and compared.

• International Journal of Contents
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• v.13 no.1
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• pp.76-85
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• 2017

This paper compares the difference in the degree of advertising avoidance between traditional media and the Internet. The study also examines customers' beliefs, attitudes, and behavior toward advertising to build a theoretical model that explains advertising avoidance. A survey was conducted to identify the influential factors. Findings indicate that on comparison, YouTube advertisements on the Internet were more problematic than TV commercial breaks, leading to high advertising avoidance on the part of consumers. Finally, using path analysis, a general advertising avoidance model based on the belief-attitude-behavior hierarchy is tested. The model shows that certain beliefs about advertising have direct effects on advertising avoidance behavior as well as on the attitude toward advertising.

• Culinary science and hospitality research
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• v.13 no.2
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• pp.153-162
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• 2007

The purpose of this study was to examine the mediating role of nausea, learned food aversion, and appetite on the relationship between food neophobia and food rejection. A total of 250(122 healthy males and 128 healthy females) questionnaires were completed. Path analytic model was used to measure the mediating effect. Results of the study demonstrated that the path analytic result for the data also indicated excellent model fit. Furthermore, the mediating analysis indicated that the influence of food neophobia was mediated by mediator. The effect of food neophobia on appetite was perfectly mediated by nausea and learned food aversion. In the contests of general food rejection, the effect of food neophobia on food rejection was perfectly mediated by appetite. It should be noted that the original model was modified and should, preferably, be validated in future research.

• Journal of Korean Academy of Nursing
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• v.31 no.1
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• pp.107-125
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• 2001

This study was designed to construct a structural model for quality of life of chronic gastric disease. The hypothetical model was developed based on the literature review and Pender's health promotion model. Data were collected by questionnaires from 459 patients with chronic gastric disease in a General Hospital from July 1999 to August 2000 in Seoul. Data analysis was done with SAS 6.12 for descriptive statistics and PC-LISREL 8.13 Program for Covariance structural analysis. The results are as follows : 1. The fit of the hypothetical model to the data was moderate, thus it was modified by excluding 1 path and including free parameters and 2 path to it. The modified model with path showed a good fitness to the empirical data ($\chi$2=934.87, p<.0001, GFI=0.88, AGFI=0.83, NNFI=0.86, RMSR =0.02, RMSEA=0.07). 2. The perceived barrier, health promoting behavior, self-efficacy, and self-esteem were found to have significant direct effects on the quality of life. 3. The health concept, health perception, emotional state, and social support were found to have indirect effects on quality of life of chronic gastric disease. In conclusion, the derived model in this study is considered appropriate in explaining and predicting quality of life of chronic gastric disease. Therefore it can effectively be used as a reference model for further studies and suggested direction in nursing practice.

• Journal of Korea Multimedia Society
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• v.9 no.12
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• pp.1607-1616
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• 2006

The growing market of multimedia and digital signal processing requires significant data-path portions of SoCs. However, the common models for verification are not suitable for SoCs. A novel model--WGL (Weighted Generalized List) is proposed, which is based on the general-list decomposition of polynomials, with three different weights and manipulation rules introduced to effect node sharing and the canonicity. Timing parameters and operations on them are also considered. Examples show the word-level WGL is the only model to linearly represent the common word-level functions and the bit-level WGL is especially suitable for arithmetic intensive circuits. The model is proved to be a uniform and efficient model for both bit-level and word-level functions. Then Based on the WGL model, a backward-construction logic-verification approach is presented, which reduces time and space complexity for multipliers to polynomial complexity(time complexity is less than $O(n^{3.6})$ and space complexity is less than $O(n^{1.5})$) without hierarchical partitioning. Finally, a construction methodology of word-level polynomials is also presented in order to implement complex high-level verification, which combines order computation and coefficient solving, and adopts an efficient backward approach. The construction complexity is much less than the existing ones, e.g. the construction time for multipliers grows at the power of less than 1.6 in the size of the input word without increasing the maximal space required. The WGL model and the verification methods based on WGL show their theoretical and applicable significance in SoC design.

• Journal of the Semiconductor & Display Technology
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• v.9 no.4
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• pp.45-50
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• 2010

This paper explores a new approach for modeling of decision-making problems that involve uncertain, time-dependent and sequence-dependent processes which can be applied to semiconductor industry. In the proposed approach, which is based on probability theory, approximate sample paths are required to be specified by probability and statistic characteristics. Completely specified sample paths are seen to be elementary and fundamental outcomes of the related experiment. The proposed approach is suitable for modeling real processes more accurately. A case study is applied to a single item production planning problem with continuous and uncertain demand and the solution obtained by the approximate path specification method shows less computational efforts and practically desirable features. The application possibility and general plan of the proposed approach in semiconductor manufacturing process is also described in the paper.

• Asia pacific journal of information systems
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• v.27 no.3
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• pp.176-190
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• 2017

This study aimed to investigate the roles of three health-oriented personal factors-health technology innovativeness (HTI), health consciousness (HC), and health information orientation (HIO)-in determining Koreans' perceptions about telemedicine. Based on an extended version of the technology acceptance model (TAM), two perceptual components-perceived usefulness (PU) and perceived ease of use (PEOU)-of telemedicine were considered for this investigation. Data from 699 usable surveys were analyzed using path analysis. The results from the path analysis indicated that while HTI and HC had no or limited effects on the PU and PEOU of telemedicine, the effects of HIO on those two perceptual components of telemedicine were statistically significant. Moreover, the results from the path analysis showed that there were significant regional differences in the effects of HTI and HC on the PU and PEOU of telemedicine. In general, these effects were greater among the metropolitan residents than they were among the rural residents.

• Journal of Korean Academy of Nursing
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• v.31 no.3
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• pp.477-491
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• 2001

Purpose: This study was designed to construct a structural model for health promoting behavior in patients with chronic respiratory disease. A hypothetical model was developed based on the literature review. Method: Data was collected by questionnaires from 235 patients with chronic respiratory disease in a General Hospital in Seoul. Data analysis was done using SAS 6.12 for descriptive statistics and the PC-LISREL 8.13 Program for Covariance Structural Analysis. Result: The results are as follows : 1. The fit of the hypothetical model to the data was moderate. It was modified by excluding 2 path and including free parameters and 3 path to it. The modified model with path showed a good fitness to the empirical data($\chi$2=80.20, P=0.05, GFI=0.95, AGFI=0.88, NNFI=0.95, NFI=0.96, RMSR=0.01, RMSEA =0.06). 2. The perceived benefits, self-efficacy, and a plan of action were found to have significant direct effects on the health promoting behavior in patients with chronic respiratory disease. 3. The health perception, self-esteem, and activity related to affect were found to have indirect effects on the health promoting behavior in patients with chronic respiratory disease. Conclusion: The modified model of this study is considered appropriate in explaining and predicting health promoting behavior in patients with chronic respiratory disease. Therefore, it can effectively be used as a reference model for further studies and suggested direction in nursing practice.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12A
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• pp.1985-1991
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• 1999

In this paper, complete and general two-port lumped Spice-network model is developed for a lossy transmission line. This model is realized as a Spice subcircuit, by means of standard lumped network elements and mathematical functions. It is used as a component in the time-domain simulation of a high-speed data transmission line such as IMI(Inter Module Interface) data path in HANbit ACE 64 ATM switching system. The only required Spice network elements are resistance and frequency-dependent controlled-voltage sources. Such frequency-dependent sources are realized by utilizing the standard Hspice mathematical functions FREQ, DELAY, and POLY.