• Tribology and Lubricants
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• v.34 no.2
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• pp.55-59
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• 2018

This paper proposes a new type of electro-mechanical wedge brake for commercial vehicles. The brake operates on a novel mechanism for self-boosting braking friction forces using eccentric shafts, and involves wedges that are inserted between the rampbridge and traverse; this self-boosting mechanism is explained herein. A dynamic analysis using ADAMS was conducted, and the findings are reported. The constraint and contact conditions are explained to verify the precision of the dynamic analysis. The dynamic analysis shows that in the proposed mechanism, the self-boosting effect occurs as desired. However, it is also noted that the system has a limitation in terms of the production of unlimited braking forces that can jam the roller inside the wedges. After demonstrating the self-boosting effect, dynamic analyses are performed for several values of the wedge angles and friction coefficients between the brake pads and disks. Conventionally, a lower wedge angle has been suggested owing to its provision of a larger clamping force for given friction coefficients. However, it is noted that lower wedge angles can lead to a higher probability of occurrence of undesirable high braking forces, which can jam the roller into the wedge; thus, a larger wedge angle is preferable for avoiding the undesirable jamming phenomena. These analysis results are presented and discussed herein.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.15-20
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• 2016

The existing multiple modulus-based self-recovering equalization type has not been applied to initial equalization. Instead, it was used for steady-state performance improvement. In this paper, for the self-recovering equalization type that considers the multiple modulus as a desired response, the initial convergence performance was improved by extending the dynamics of the errors using error boosting and their characteristics were analyzed. Error boosting in the proposed method was carried out in proportion to a symbol decision for the equalizer output. Furthermore, having the initial convergence capability by extending the dynamics of errors, it showed excellent performance in the initial convergence rate and steady-state error level. In particular, the proposed method can be applied to the entire process of equalization through a single algorithm; the existing methods of switching over or the selection of other operation modes, such as concurrent operating with other algorithms, are not necessary. The usefulness of the proposed method was verified by simulations performed under the channel conditions with multipath propagation and additional noise, and for performance analysis of self-recovering equalization for high-order signal constellations.

• Journal of IKEEE
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• v.25 no.4
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• pp.778-781
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• 2021

In this paper, we propose the 16-layer 3D NAND Flash memory compact modeling using SPICE. In the same structure and simulation conditions, the channel potential about Down Coupling Phenomenon(DCP) and Natural Local Self Boosting (NLSB) were simulated and analyzed with Technology Computer Aided Design(TCAD) tool Atlas(Silvaco^TM) and SPICE, respectively. As a result, it was confirmed that the channel potential of TCAD and SPICE for the two phenomena were almost same. The SPICE can be checked the device structure intuitively by using netlist. Also, its simulation time is shorter than TCAD. Therefore, using SPICE can be expected to efficient research on 3D NAND Flash memory.

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.6
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• pp.573-579
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• 2013

Hydrogen engine with homogeneous charged compression ignition can achieve high efficiency by high compression ratio and rapid chemical reaction rates spatially. However, it needs to expansion of the operation range with over-all load conditions which is very narrow due to extremely high pressure rise rate. The adoption of the lean boosting in a HCCI $H_2$ engine is expected to be effective in expansion of operation range since minimum compression ratio for spontaneous ignition is decreased by low temperature combustion and increased surround in-cylinder pressure. In order to grasp its possibility by using lean boosting in the HCCI $H_2$ engine, compression ratio required for spontaneous ignition, expansion degree of the operation range and over-all engine performance are experimentally analyzed with the boosting pressure and supply energy. As the results, it is found that minimum compression ratio for spontaneous ignition is down to the compression ratio(${\varepsilon}$=19) of conventional diesel engine due to decreased self-ignition temperature, and operation range is extended to 170% in term of the equivalence ratio and 12 times in term of the supply energy than that of naturally aspirated type. Though indicated thermal efficiency is decreased by reduced compression ratio, it is over at least 46%.

• Journal of the Korean Home Economics Association
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• v.49 no.10
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• pp.71-79
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• 2011

When adolescents undergo the period of transition, they need to promote self-confidence from social support by parents, teachers or friends. It was believed that boosting subjective perception on their main areas of interest such as academic performance, appearance and fashion will result in happiness. The main purpose of this study was to investigate the influence of social support including family support, teacher support and friend support on self management, appearance satisfaction and fashion opinion leadership. A total of 412 questionnaires from the middle and high school students living in or near Seoul were collected and analyzed. The results indicated that teacher support and family support had a positive effect on self-management and family support had a positive effect on appearance satisfaction. Furthermore, friend support had a positive effect on fashion opinion leadership. In conclusion, implications for promoting self-confidence related to self-management, appearance satisfaction and fashion opinion leadership with the help of social support are suggested.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.335-341
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• 2014

Cancer is a menace fast gaining momentum in Nigeria and other developing countries. It is an expensive disease requiring a major financial and human resources for prevention, diagnosis and treatment. With no national policy on cancer control in the conntry, incidence (111.7/100,000 population) and mortality (86.6/100,000) rates in Nigeria are spiraling beyond control. This literature search study was primarily aimed at providing recommendations on cost-effective strategies for development interventions to promote self-management for cancer survivors in Nigeria with a goal to improve quality of life and overall survival.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.1
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• pp.125-132
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• 2007

Within the framework of brake-by-wire technology, this paper presents five types of novel models of electro-mechanical disk brake calipers with self-servo mechanism which provides self-servo effect of boosting a friction force generated between the brake pad and the rotor disk surface. The models have been developed utilizing patent map analysis results of previous invents of electro-mechanical brake calipers. The feasibility of the developed motor-driven brake caliper models have been validated through the dynamic simulation analysis. Among the developed models, the caliper mechanism with separated pressure plate was designed especially in detail and was made as a pilot. The pilot caliper has been installed on the simple test bed constructed with domestic passenger car brake components, and its function and effectiveness have been validated through several types of experimental tests.

• Knowledge Management Research
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• v.18 no.4
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• pp.261-286
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• 2017

Key factors enhancing transfer behavior of training and knowledge sharing are of great interest to researchers and executives because training transfer and knowledge sharing activities are remarkable predictors of organizational growth. This study investigates the core motivations for boosting transfer behavior of training and knowledge sharing. To empirically test the impacts of employee training, servant leadership and self-efficacy, a survey was conducted in small-medium sized companies. The data (N=292) were analyzed using structural equation modeling analysis. The results indicate that higher employee training positively leads to self-efficacy and transfer behavior of training. Servant leadership is positively leads to self-efficacy, transfer behavior of training, and knowledge sharing. Self-efficacy of employees induces greater transfer behavior of training and knowledge sharing. Finally, transfer behavior of training encourages workers to increase knowledge sharing. This study represents an initial step to examine the psychological mechanism of improving employees' transfer behavior of training and knowledge sharing activities based on the employee training qualities and servant leaderships.

• International Journal of Computer Science & Network Security
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• v.23 no.5
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• pp.135-147
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• 2023

Internet of things has revolutionaries every field of life due to the use of artificial intelligence within Machine Learning. It is successfully being used for the study of Radiation monitoring, prediction of Ultraviolet and Electromagnetic rays. However, there is no particular system available that can monitor and detect waves. Therefore, the present study designed in which IOT enables intelligence system based on machine learning was developed for the prediction of the radiation and their effects of human beings. Moreover, a sensor based system was installed in order to detect harmful radiation present in the environment and this system has the ability to alert the humans within the range of danger zone with a buzz, so that humans can move to a safer place. Along with this automatic sensor system; a self-created dataset was also created in which sensor values were recorded. Furthermore, in order to study the outcomes of the effect of these rays researchers used Support Vector Machine, Gaussian Naïve Bayes, Decision Trees, Extra Trees, Bagging Classifier, Random Forests, Logistic Regression and Adaptive Boosting Classifier were used. To sum up the whole discussion it is stated the results give high accuracy and prove that the proposed system is reliable and accurate for the detection and monitoring of waves. Furthermore, for the prediction of outcome, Adaptive Boosting Classifier has shown the best accuracy of 81.77% as compared with other classifiers.

• Structural Engineering and Mechanics
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• v.84 no.5
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• pp.605-618
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• 2022

Glass fiber reinforced polymer (GFRP) elastic gridshells consist of long continuous GFRP tubes that form elastic deformations. In this paper, a method for the form-finding of gridshell structures is presented based on the interpretable machine learning (ML) approaches. A comparative study is conducted on several ML algorithms, including support vector regression (SVR), K-nearest neighbors (KNN), decision tree (DT), random forest (RF), AdaBoost, XGBoost, category boosting (CatBoost), and light gradient boosting machine (LightGBM). A numerical example is presented using a standard double-hump gridshell considering two characteristics of deformation as objective functions. The combination of the grid search approach and k-fold cross-validation (CV) is implemented for fine-tuning the parameters of ML models. The results of the comparative study indicate that the LightGBM model presents the highest prediction accuracy. Finally, interpretable ML approaches, including Shapely additive explanations (SHAP), partial dependence plot (PDP), and accumulated local effects (ALE), are applied to explain the predictions of the ML model since it is essential to understand the effect of various values of input parameters on objective functions. As a result of interpretability approaches, an optimum gridshell structure is obtained and new opportunities are verified for form-finding investigation of GFRP elastic gridshells during lifting construction.