• Journal of the Korean Solar Energy Society
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• v.35 no.3
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• pp.17-25
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• 2015

The main objective of this study is to predict the wind power generation at the wind farm using various wake models. Modeling of wind farm is a prerequisite for prediction of annual energy production at the wind farm. In this study, we modeled 20 MW class Seongsan wind farm which has 10 wind turbines located at the eastern part of Jeju Island. WindSim based on the computational fluid dynamics was adopted for the estimation of power generation. The power curve and thrust coefficient with meteorology file were prepared for wind farm modelling. The meteorology file was produced based on the measured data of the Korea Wind Atlas provided by Korea Institute of Energy Research. Three types of wake models such as Jensen, Larsen, and Ishihara et al. wake models were applied to investigate the wake effects. From the result, Jensen and Ishihara wake models show nearly the same value of power generation whereas the Larsen wake model shows the largest value. New positions of wind turbines are proposed to reduce the wake loss, and to increase the annual energy production of the wind farm.

• Knowledge Management Research
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• v.19 no.4
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• pp.77-98
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• 2018

The purpose of this paper is examine the existing relations structure and IT use for collaboration activities on supply chain and their impacts on the performance of supply chain. This study made a design of the research model that was further constructed by integrating the relationship structure, IT exploration, IT exploitation, supply chain collaboration, absorptive capacity, and knowledge creation, efficiency and efficient. The survey data were collected from 378 companies, where firms are facing increased global competitive pressure and heavily utilize SCM to retain their competitive advantages. The authors validated a measurement model with structural equation modelling and tested eight hypotheses. As a result, the absorptive capacity was closely related to trust, IT exploitation and IT exploration, but supply chain collaboration. Examining the effect of supply chain collaboration with two types of absorptive capacity, the authors found positive effect on potential absorptive capacity, but a non-significant effect on realized absorptive capacity. This finding suggests that the improving performance of supply chain not only is related to the relations structure and IT use on supply chain, but also is closely related to the absorptive capacity.

• Journal of Distribution Science
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• v.20 no.12
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• pp.59-69
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• 2022

Purpose: The purpose of this research is to identify and design a model for the integration between marketing and supply chain management (SCM) of technopreneurship-based souvenirs MSMEs to fulfil customer value creation. Research design, data and methodology: This research method uses the system development life cycle method. This study draws its insights and conclusions from a literature review in several fields followed by an interactive research approach that helps identify, validate, and implement a theoretical framework so that the modelling results can be adopted in applicative manner for souvenir MSMEs. Result: Implementing the "G-ASPOO-L" supply chain management integration model based on technopreneruship to fulfil value creation in the 5.0 society era created three perspectives: an inter-functional perspective, a process perspective, and an integrated business concept perspective. The supply chain management involves enterprise integration, strategic customer integration, strategic supplier integration, and marketing strategy integration. Conclusion: The proposed model framework leads to managerial problems of supply chain management strategy, which urgently requires an interaction approach that challenges the traditional view of demand creation and implementation of supply chain management to fulfil value creation. This research leverages existing knowledge and advances our understanding of the strategic integration issues companies face in digital-based competition.

• Journal of Positioning, Navigation, and Timing
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• v.10 no.1
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• pp.55-66
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• 2021

In this paper, we propose a signal propagation modeling technique for generating a positioning fingerprint DB based on Long Term Evolution (LTE) signals. When a DB is created based on the location-based signal information collected in an urban area, gaps in the DB due to uncollected areas occur. The spatial interpolation method for filling the gaps has limitations. In addition, the existing gap filling technique through signal propagation modeling does not reflect the signal attenuation characteristics according to directions occurring in urban areas by considering only the signal attenuation characteristics according to distance. To solve this problem, this paper proposes a Deep Neural Network (DNN)-based signal propagation functionalization technique that considers distance and direction together. To verify the performance of this technique, an experiment was conducted in Seocho-gu, Seoul. Based on the acquired signals, signal propagation characteristics were modeled for each method, and Root Mean Squared Errors (RMSE) was calculated using the verification data to perform comparative analysis. As a result, it was shown that the proposed technique is improved by about 4.284 dBm compared to the existing signal propagation model. Through this, it can be confirmed that the DNN-based signal propagation model proposed in this paper is excellent in performance, and it is expected that the positioning performance will be improved based on the fingerprint DB generated through it.

• SUVANNABHUMI
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• v.13 no.2
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• pp.167-186
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• 2021

The Grand Stupa is mentioned in historical text as 'Rajakudakan', which means a royal building with a multitiered superstructure. This Grand Stupa is the principal construction of Wat Chedi Luang, and marks the center of the Chiang Mai City Plan. This study argues that the Grand Stupa was built in 1391 during Phaya Saen Mueang Ma's reign, possibly inspired by the construction of Ku Phaya in Bagan. Thereafter, in 1545, the Grand Stupa's superstructure collapsed after the great earthquake, resulted in the irreparable damage since then. Therefore, a survey using a 3D laser scanner is conducted to collect the most precise data on the current condition of the Grand Stupa, yielding an assumption of its reconstruction. Other simultaneous stupas or those that show a close architectural relationship (e.g. stupas in Wat Chiang Man and Wat Lok Moli and the stupa of King Tilokaraj in Wat Chet Yot in Chiang Mai) are also employed as research frameworks for the reconstruction. As a result, the architectural research on the Grands Stupa, compared with simultaneous stupas, yields a fruitful argument that the pre-collapse superstructure form of the Grand Stupa marks the most architectural similarity to the stupa of Wat Chiang Man.

• Animal Bioscience
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• v.36 no.10
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• pp.1546-1557
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• 2023

Objective: The present study aimed to evaluate the effects of extruded and unextruded feeding on the performance, milk composition, digestibility and ruminal fermentation of dairy cows through a meta-analysis. Methods: The database was compiled from 53 studies in Scopus and PubMed. The data were analyzed using a random effects model in OpenMEE software. Extruded feed was grouped as the experiment group while and the others as control group. The bias of publication in the main parameter of dairy performance was evaluated by a funnel plot. Results: The result showed that extruded feed enhanced the milk yield, dry matter and crude protein digestibility, butyrate and valerate acid production (p<0.05). Meanwhile, the extruded feed significantly decreased the milk fat and protein concentration (p<0.05). Also, the iso-butyrate and iso-valerate in unextruded feeding was significantly higher than the extruded feed (p<0.05). Conclusion: It was concluded from the meta-analysis that extruded feed effectively improved the milk production and milk lactose concentration, dry matter and protein digestibility, but not the milk fat and protein concentration.

• Journal of Distribution Science
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• v.21 no.10
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• pp.11-19
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• 2023

Purpose: Personality qualities are essential to the prosperity of any contemporary company because they foster the growth of pleasant emotions in telecommunications distribution employees. Research design, data and methodology: Thus improving their overall psychological well-being and productivity. Talent retention is facilitated by mutual respect between management and staff. The success of the company as a whole, including the development and maintenance of emotions with customers, also depends on the psychological well-being of employees. The aim is to demonstrate how a positive and satisfied emotional workforce contributes to psychological well-being in the 21st century. Result: The research aims to better understand the personality traits that influence the psychological well-being of employees. In addition, between January and March 2023, a total of 179 employees in the telecommunications distribution industry in the Peruvian city of Chiclayo were surveyed using structural modelling methods to measure employee satisfaction. It also shows how various ideas, approaches and models can be used in the real world. Conclusion: The significance of the model on the perception of telecommunications workers in Peru is demonstrated by the results, which indicate an R² value of 0.681 for positive emotions and an R² value of 0.792 for employees' psychological well-being.

• Ocean and Polar Research
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• v.29 no.1
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• pp.9-31
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• 2007

Most seismic sea waves in the East Sea originate from earthquakes occurring near the Japanese west coast. While the waves propagate in the East Sea, they are deformed by refraction, diffraction and scattering. Though the Boussinesq equation is most applicable for such wave phenomena, it was not used in numerical modelling of seismic sea waves in the East Sea. To examine characteristics of seismic sea waves in the East Sea, numerical models based on the Boussinesq equation are established and used to simulate recent tsunamis. By considering Ursell parameter and Kajiura parameter, it is proved that Boussinesq equation is a proper equation for seismic sea waves in the East Sea. Two models based on the Boussinesq equation and linear wave equation are executed with the same initial conditions and grid size ($1min{\times}1min$), and the results are compared in various respects. The Boussinesq equation model produced better results than the linear model in respect to wave propagation and concentration of wave energy. It is also certified that the Boussinesq equation model can be used for operational purpose if it is optimized. Another Boussinesq equation model whose grid size is $40sec{\times}30sec$ is set up to simulate the 1983 and 1993 tsunamis. As the result of simulation, new propagation charts of 2 seismic sea waves focused on the Korean east coast are proposed. Even though the 1983 and 1993 tsunamis started at different areas, the propagation paths near the Korean east coast are similar and they can be distinguished into 4 paths. Among these, total energy and propagating time of the waves passing over North Korea Plateau(NKP) and South Korea Plateau(SKP) determine wave height at the Korean east coast. In case of the 1993 tsunami, the wave passing over NKP has more energy than the wave over SKP. In case of the 1983 tsunami, the huge energy of the wave passing over SKP brought about great maximum wave heights at Mukho and Imwon. The Boussinesq equation model established in this study is more useful for simulation of seismic sea waves near the Korean east coast than it is the Japanese coast. To improve understanding of seismic sea waves in shallow water, a coastal area model based on the Boussinesq equation is also required.

• Journal of IKEEE
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• v.20 no.4
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• pp.398-411
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• 2016

SVM, a machine learning method, is widely used in image processing for it's excellent generalization performance. However, to add other data to the pre-trained data of the system, we need to train the entire system again. This procedure takes a lot of time, especially in embedded environment, and results in low performance of SVM. In this paper, we implemented an SVM trainer and classifier in an FPGA to solve this problem. We parlallelized the repeated operations inside SVM and modified the exponential operations of the kernel function to perform fixed point modelling. We implemented the proposed hardware on Xilinx ZC 706 evaluation board and used TSR algorithm to verify the FPGA result. It takes about 5 seconds for the proposed hardware to train 2,000 data samples and 16.54ms for classification for $1360{\times}800$ resolution in 100MHz frequency, respectively.

• Korean Journal of Construction Engineering and Management
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• v.14 no.3
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• pp.88-96
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• 2013

Recent proliferation of building information modeling (BIM) has actively stimulated integrated utilization of geometric (graphic) and non-geometric (non-graphic) data. Nevertheless, physically and logically, linking and maintaining these two different types of data in an integrated manner requires enormous overhead efforts for practical implementation. In order to address this problem, this paper proposes a concept and structure of the object breakdown structure (OBS) that facilitates advanced BIM implementations in an automated and effective manner. Proposed OBS numbering system has secure rules for organizing graphic objects in full considerations of effectively integrating with non-geometric data (e.g. cost and schedule). It also removes repetitive linking process caused by design changes or modifications. The result of applying this concept to a housing project revealed that only 120 definitions controled over 6,000 graphic objects for full integration with cost and schedule functions.