• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.12
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• pp.21-26
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• 2011

This is a study to establish regulations against light pollution for lighting on roads. Many kinds of light pollution by luminaire on roads was calculated and analyzed by applying the classification method of luminaires(Cut-off classification of IDA-IESNA, BUG Rating Classification) and the calculation method of Upward Lighting Ratio of CIE among measures to prevent light pollution that international lighting organizations suggest. As a result of the analysis, it was found that the regulation by Cutoff of IESNA and ULR classification of CIE could be one for scattered light of light pollution compared to BUG classification but is not sufficient for the regulation of light tresspass or glare. BUG classification by each lighting zone was suggested as threshold value of the light pollution regulation considering domestic conditions.

• Earthquakes and Structures
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• v.14 no.5
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• pp.477-492
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• 2018

Recently, the adaptive nonlinear static analysis method has been widely used in the field of performance based earthquake engineering. However, the proposed methods are almost deterministic and cannot directly consider the seismic record uncertainties. In the current study an innovative Stochastic Adaptive Pushover Analysis, called "SAPA", based on equivalent hysteresis system responses is developed to consider the earthquake record to record uncertainties. The methodology offers a direct stochastic analysis which estimates the seismic demands of the structure in a probabilistic manner. In this procedure by using a stochastic linearization technique in each step, the equivalent hysteresis system is analyzed and the probabilistic characteristics of the result are obtained by which the lateral force pattern is extracted and the actual structure is pushed. To compare the results, three different types of analysis have been considered; conventional pushover methods, incremental dynamic analysis, IDA, and the SAPA method. The result shows an admirable accuracy in predicting the structure responses.

• Steel and Composite Structures
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• v.37 no.2
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• pp.151-173
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• 2020

This paper aims to probabilistically evaluate performance of two types of I beam to box column (IBBC) connection. With the objective of considering the variability of seismic loading demand, statistical features of the inter-story drift ratio corresponding to the second, fifth and eleventh story of a 12-story steel special moment resisting frames are extracted through incremental dynamic analysis at global collapse state. Variability of geometrical variables and material strength are also taken into account. All of these random variables are exported as inputs to a probabilistic finite element model which simulates the connection. At the end, cumulative distribution functions of local seismic demand for each component of each connection are provided using histogram sampling. Through a parametric study on probabilistic local seismic demand, the influence of some geometrical random variables on the performance of IBBC connections is demonstrated. Furthermore, the probabilistic study revealed that IBBC connection with widened flange has a better performance than the un-widened flange. Also, a design procedure is proposed for WF connections to achieve a same connection performance in different stories.

• Earthquakes and Structures
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• v.20 no.2
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• pp.225-238
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• 2021

Supplemental passive dampers are widely employed to improve the structural performance of buildings under seismic excitations. Nevertheless, the added damping could be counter-productive if the axial forces induced by the damper reaction forces are not routed properly in the columns. A few researchers engaged to optimize the width-wise damper arrangement to improve the delivered path of the axial column forces. However, most of these studies are limited under the design-based seismic level and few of them has evaluated the collapse performance of buildings under strong earthquakes. In this paper, the strategic width-wise placement method of viscous dampers is explored regarding the building performance under collapse state. Two realistic steel buildings with different storeys are modelled and compared to explore higher mode effects. Each building is designed with four different damper arrangement scenarios based on a classic damper distribution method. Both a far-fault and a near-fault seismic environment are considered for the buildings. Incremental Dynamic Analysis (IDA) is performed to evaluate the probability of collapse and the plastic mechanism of the retrofitted steel buildings.

• Journal of information and communication convergence engineering
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• v.15 no.1
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• pp.53-61
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• 2017

The preferred feature selection methods for text classification are filter-based. In a common filter-based feature selection scheme, unique scores are assigned to features; then, these features are sorted according to their scores. The last step is to add the top-N features to the feature set. In this paper, we propose an improved global feature selection scheme wherein its last step is modified to obtain a more representative feature set. The proposed method aims to improve the classification performance of global feature selection methods by creating a feature set representing all classes almost equally. For this purpose, a local feature selection method is used in the proposed method to label features according to their discriminative power on classes; these labels are used while producing the feature sets. Experimental results obtained using the well-known 20 Newsgroups and Reuters-21578 datasets with the k-nearest neighbor algorithm and a support vector machine indicate that the proposed method improves the classification performance in terms of a widely known metric ($F_1$).

• Journal of the Society of Naval Architects of Korea
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• v.48 no.6
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• pp.528-538
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• 2011

As a forming method for curved hull plates more efficient than the flame bending, mechanical bending using multi point press forming and die-less forming is discussed in this paper. the mechanical forming is a flexible manufacturing system for automatically forming of hull parts. It is especially suited to varied curved parts. This paper discusses a multiple point pressing machine composed of a pair of reconfigurable punches in order to achieve the rapid forming of curved hull plates using division forming and presents how forming information is obtained from the given design surface. Although the mechanical forming can be efficient in the metal forming, spring back after pressing is a phenomenon which must be carefully considered when quantifying the process variables. If the spring back is not accurately controlled, the fabricated shell plate cannot meet assembly tolerance. This paper describes the principles to calculate the proper stroke of each punch at the divided areas. the strokes are determined by an iterative process of sequential pressing and spring back compensation from an unfolded flat shape to its given design surface. FEA(finite element analysis) is used to simulate the spring back of the plate and the IDA(iterative displacement adjustment) method adjusts the offset of pressing punches from the deformation results and the design surface. The shape deviations of two surfaces due to spring back are compensated by integrated system using FEA and IDA method. For the practical application, It is aimed to develop an integrated system that can automatically perform the compensation process and calculate strokes of punches of the double sides' reconfigurable multiple-press machine and some experimental results obtained with mechanical bending are presented.

• Asian Journal of Innovation and Policy
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• v.7 no.1
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• pp.178-189
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• 2018

In this paper, we present a case study of a new emerging business startup involved in smart house appliances. The irreversible investment concept and real-option theory are introduced as the fundamentals of the model. By using games theory we show that the startup's actions can trigger reactions from other firms. The first part covers initial the research and development stage, while the second part covers production and commercialization. The findings of this study suggest that, given a certain amount of initial investment, an open and shared innovation may lead to hurting a firm's investment while strengthening the competitors' position in the market. However, given the sensitivity analysis, when volatility and demand grow favorably, sharing R&D investment is not a bad option for a new player to adjust its position in the market while still maintaining positive returns.

• Journal of information and communication convergence engineering
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• v.16 no.2
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• pp.106-113
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• 2018

Although deep learning methods of convolutional neural networks (CNNs) and long-/short-term memory (LSTM) are widely used for text categorization, they still have certain shortcomings. CNNs require that the text retain some order, that the pooling lengths be identical, and that collateral analysis is impossible; In case of LSTM, it requires the unidirectional operation and the inputs/outputs are very complex. Against these problems, we thus improved these traditional deep learning methods in the following ways: We created collateral CNNs accepting disorder and variable-length pooling, and we removed the input/output gates when creating bidirectional LSTMs. We have used four benchmark datasets for topic and sentiment classification using the new methods that we propose. The best results were obtained by combining LTSM regional embeddings with data convolution. Our method is better than all previous methods (including deep learning methods) in terms of topic and sentiment classification.

• Computers and Concrete
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• v.29 no.1
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• pp.59-67
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• 2022

In this paper, a reliability-based approach has been implemented to develop seismic analytical fragility curves of highway bridges. A typical bridge class of the Central and South-eastern United States (CSUS) region was selected. Detailed finite element modelling is presented and Incremental Dynamic Analysis (IDA) is used to capture the behavior of the bridge from linear to nonlinear behavior. Bayesian linear regression method is used to define the demand model. A reliability approach is implemented to generate the analytical fragility curves and the proposed approach is compared with the conventional fragility analysis procedure.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.1215-1224
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• 2020

Micro, Small and Medium Enterprises in Denpasar City still face low mastery of technology and financial management, one of which is the application of technology-based accounting information systems (e-commerce) for small and medium enterprises. The research objective was to determine the relationship between environmental uncertainty, trust and ease of information technology moderating behavior in accounting information systems. Research with a quantitative approach, the method used is multiple linear regression with moderated regression analysis. The study population was 816 small and medium enterprises. The sampling method technique was the incidental sampling approach and the Slovin formula so that a sampling of 100 small and medium enterprises that had used e-commerce was determined in the city of Denpasar. The results of research that have been conducted determine the relationship between user behavior in accounting information systems that affect individual performance, the relationship between environmental uncertainty affects accounting information systems mediated by individual performance, while the ease of information technology and its ability to be mediated by individual performance has an effect on the behavior of using accounting information systems. The application of accounting information systems in small and medium enterprises is expected to improve individual performance so as to increase income.