Browsing by Issue Date, starting with "2017-03"

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Time periodic saturated flow boiling heat transfer of R-134a in a narrow annular duct due to heat flux oscillation
(2017-03)
Chen, C. A.
;
Lin, T. F.
;
Yan, Wei-Mon
;
機械工程學系
;
Department of Mechanical Engineering
The time periodic saturated boiling heat transfer in a horizontal annulus was investigated experimentally where the walls are under an oscillating heat flux. The fluid enters the duct with zero vapor quality (saturated liquid state). The amplitude of the imposed heat flux oscillation Delta q varies from 0% to 50% of mean imposed heat flux (q) over bar and four different periods of heat flux oscillation t(p) including 20, 30, 60 and 120 s are applied to the system. The measured data display that when the applied heat flux is close to that for the onset of stable flow boiling, intermittent flow boiling appears in which nucleate boiling on the heated surface only exists in a partial interval of each periodic cycle and the heat flux oscillation does not noticeably affect the time-average boiling curves and heat transfer coefficients. Besides, the heated wall temperature and evaporating flow pattern are found to oscillate periodically in time as well and at the same frequency as the imposed heat flux oscillation. Furthermore, in the persistent boiling the resulting oscillation amplitudes of the heated surface temperature, heat transfer coefficient gets larger for a longer period and larger amplitude of the imposed heat flux oscillation and for a higher mean imposed heat flux. The substantial time lag in the heated surface temperature oscillation is observed. In the first half of the periodic cycle in which the heat flux reduces with time, after the time lag the heated wall temperature decreases with time. The inverse processes occur in the second half of the cycle in which imposed heat flux increases with time. Finally, flow regime maps are provided to explain the boundaries separating different boiling regimes for the R-134a saturated boiling in the duct. (C) 2016 Elsevier Ltd. All rights reserved.
Only-One-Victor Pattern Learning in Computer Go
(2017-03-01)
Wang, Jiao
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Xiao, Chenjun
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Zhu, Tan
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Hsueh, Chu-Husan
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Tseng, Wen-Jie
Automatically acquiring domain knowledge from professional game records, a kind of pattern learning, is an attractive and challenging issue in computer Go. This paper proposes a supervised learning method, by introducing a new generalized Bradley-Terry model, named Only-One-Victor, to learn patterns from game records. Basically, our algorithm applies the same idea with Elo rating algorithm, which considers each move in game records as a group of move patterns, and the selected move as the winner of a kind of competition among all groups on current board. However, being different from the generalized Bradley-Terry model for group competition used in Elo rating algorithm, Only-One-Victor model in our work simulates the process of making selection from a set of possible candidates by considering such process as a group of independent pairwise comparisons. We use a graph theory model to prove the correctness of Only-One-Victor model. In addition, we also apply the Minorization-Maximization (MM) to solve the optimization task. Therefore, our algorithm still enjoys many computational advantages of Elo rating algorithm, such as the scalability with high dimensional feature space. With the training set containing 115,832 moves and the same feature setting, the results of our experiments show that Only-One-Victor outperforms Elo rating, a well-known best supervised pattern learning method.
A Model for Neutral Defect Limited Electron Mobility in Strained-Silicon Inversion Layers
(2017-03-01)
Hsieh, Shang-Hsun
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Chen, Ming-Jer
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電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
On the strained silicon metal-oxide-semiconductor field-effect transistors (MOSFETs), we show how to derive a formalism dealing with the scattering of a 2-D electron by a neutral defect. The corresponding neutral defect limited inversion-layer electron mobility, mu(n), is calculated in the momentum relaxation time approximation. The calculated results lead to a new analytical model: mu(n) = cN(n)(-1) where N-n is the neutral defect density per unit area and c is the coefficient independent of the inversion-layer density, the strain, and the temperature. The validity and applicability of the model are confirmed by citing three independent experiments on strained silicon MOSFETs undergoing different implantation sources and different annealing budgets. Importantly, this paper clarifies for the first time that strain will not change neutral defect limited mobility unless changing the neutral defect density. This reasonably explains the two experimental observations during implantation and annealing: 1) the implantation-induced strain relaxation in strained sample does not occur and 2) the neutral defect density is much higher in strained sample than in unstrained sample.
Soft-Boosted Self-Constructing Neural Fuzzy Inference Network
(2017-03)
Prasad, Mukesh
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Lin, Chin-Teng
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Li, Dong-Lin
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Hong, Chao-Tien
;
Ding, Wei-Ping
This correspondence paper proposes an improved version of the self-constructing neural fuzzy inference network (SONFIN), called soft-boosted SONFIN (SB-SONFIN). The design softly boosts the learning process of the SONFIN in order to decrease the error rate and enhance the learning speed. The SB-SONFIN boosts the learning power of the SONFIN by taking into account the numbers of fuzzy rules and initial weights which are two important parameters of the SONFIN, SB-SONFIN advances the learning process by: 1) initializing the weights with the width of the fuzzy sets rather than just with random values and 2) improving the parameter learning rates with the number of learned fuzzy rules. The effectiveness of the proposed soft boosting scheme is validated on several real world and benchmark datasets. The experimental results show that the SB-SONFIN possesses the capability to outperform other known methods on various datasets.
Novel non-contact control system of electric bed for medical healthcare
(2017-03-01)
Lo, Chi-Chun
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Tsai, Shang-Ho
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Lin, Bor-Shyh
;
影像與生醫光電研究所
;
電控工程研究所
A novel non-contact controller of the electric bed for medical healthcare was proposed in this study. Nowadays, the electric beds are widely used for hospitals and home-care, and the conventional control method of the electric beds usually involves in the manual operation. However, it is more difficult for the disabled and bedridden patients, who might totally depend on others, to operate the conventional electric beds by themselves. Different from the current controlling method, the proposed system provides a new concept of controlling the electric bed via visual stimuli, without manual operation. The disabled patients could operate the electric bed by focusing on the control icons of a visual stimulus tablet in the proposed system. Besides, a wearable and wireless EEG acquisition module was also implemented to monitor the EEG signals of patients. The experimental results showed that the proposed system successfully measured and extracted the EEG features related to visual stimuli, and the disabled patients could operate the adjustable function of the electric bed by themselves to effectively reduce the long-term care burden.
Is immersion of any value? Whether, and to what extent, game immersion experience during serious gaming affects science learning
(2017-03)
Cheng, Meng-Tzu
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Lin, Yu-Wen
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She, Hsiao-Ching
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Kuo, Po-Chih
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教育研究所
Many studies have shown the positive impact of serious gaming on learning outcomes, but few have explored the relationships between game immersion and science learning. Accordingly, this study was conducted to investigate the effectiveness of learning by playing, as well as the dynamic process of game immersion experiences, and to further identify whether, and to what extent, immersion affects science learning through serious gaming by using the techniques of cluster analysis. A total of 63 seventh-grade students participated in the study, and a quasi-experimental research design was employed. The results demonstrated that the students gained a holistic understanding of the relevant scientific concepts because their performances on the scenario-based science assessment were significantly improved across serious gameplaying occasions, and the effect of learning was retained long term. Moreover, serious gaming provided students with the experience of immersion insofar as the students indicated a greater degree of immersion in the game over time. Furthermore, two core clusters presenting meaningful patterns, high gaming performance/high immersion and high science learning/low immersion, were revealed. Finally, various interpretations and implications of the obtained data are discussed.
Determinants of profiting from innovation activities: Comparisons between technological leaders and latecomers
(2017-03-01)
Hu, Mei-Chih
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Kang, Jin-Su
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Wu, Ching-Yan
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經營管理研究所
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Institute of Business and Management
While the remarkable economic growth of the East Asian latecomers reflects the success of technological catching-up strategies, few researchers have explored the extent to which the profits of innovation have been created and managed in their social contexts and how those profits are secured differently from that of technological leaders. This pioneer study offers empirical evidence and insights by exploring how different rents (value) were secured within the existing global technological regime by technological leaders and by latecomers over the period 1990 to 2009. Our results demonstrate that technological regimes, including technological congruence and social capabilities, affect technological leaders and latecomers in different ways resulting in a relationship where the two play complementary roles. The accumulation and utilization of social capabilities are essential for developing state-of-the-art technologies and securing profit from innovations in the global market. The insights and implications for both technological leaders and latecomers are discussed and elaborated. (C) 2016 Elsevier Inc. All rights reserved.
利用高維度子空間產生取樣之方法
(2017-03-01)
林進燈
;
謝宗佑
;
劉宇庭
本發明係為一種利用高維度子空間產生取樣之方法，包括將一向量資料值投影至複數高維度子空間上，以產生複數向量子空間資料值，並取其中具有最大值之向量子空間資料值為最佳向量子空間資料值，並取其所屬子空間的維度，設為基準維度並利用梯度演算，調整其餘子空間，以產生新高維度子空間，再投影出新向量子空間資料值，判斷新向量子空間資料值與向量資料值之比值是大於或等於一預設值，若是，新向量子空間資料值則成為取樣值，若否，則回覆至第一步驟。故，本發明可產生與原始資料相似的取樣資料。
自適性（ａｄａｐｔｉｖｅ）生理反應之參數預測方法及其預測裝置
(2017-03-01)
林進燈
;
莊鈞翔
本發明係揭露一種自適性(adaptive)生理反應之參數預測方法及其預測裝置，首先，在生理狀態判斷流程中，先接收一生理資料與一第一生理訊號，據此計算出分別對應複數不同程度之生理狀態之複數生理權重值，生理權重值的總和等於1。然後，執行複數次預測流程，在每一預測流程中，係先接收一第二生理訊號，並據此計算出分別對應不同程度之生理狀態的複數生理反應值。接著，運算生理反應值與生理權重值，以產生一生理反應參數來完成預測流程。在完成複數次預測流程後，則會執行一次生理狀態判斷流程以更新生理權重值，藉此針對各種不同程度之生理狀態的使用者取得精準的預測結果。
Characterization of Temporary Bonding and Laser Release Using Polyimide and a 300-nm Photolysis Polymer System for High-Throughput 3-D IC Applications
(2017-03)
Cheng, Chuan-An
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Tsai, Tsung-Yen
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Huang, Yu-Hsiang
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Lin, Chien-Hung
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Lee, Chia-Lin
A new temporary bonding technology with an ultrafast laser-release process of less than 20 s is presented, where a 300-nm-thick photolysis polymer and polyimide are served as the release layer and adhesive layer, respectively. The submicrometer-thick polymer has the feature of high absorption of a 355-nm laser in contrast to polyimide during debonding procedures. In addition, the thin release layers of high chemical resistance and mechanical strength demonstrate their feasibility for handling process. Electrical characteristics of the devices before and after the laser-release process are investigated, showing no degradation. Thus, this technology scheme demonstrates its potential for temporary bonding and release in 3-D integration applications.
Unusual Emission of Polystyrene-Based Alternating Copolymers Incorporating Aminobutyl Maleimide Fluorophore-Containing Polyhedral Oligomeric Silsesquioxane Nanoparticles
(2017-03-01)
Mohamed, Mohamed Gamal
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Jheng, Yu-Ru
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Yeh, Shu-Ling
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Chen, Tao
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Kuo, Shiao-Wei
In this study, we synthesized an unusual 2-aminobutyl maleimide isobutyl polyhedral oligomeric silsesquioxane (MIPOSS-NHBu) monomer lacking conventional fluorescent groups. We then prepared poly(styrene-alt-2-aminobutyl maleimide isobutyl POSS) [poly(S-alt-MIPOSS-NHBu)] and poly(4-acetoxystyrene-alt-2-aminobutyl maleimide isobutyl POSS) [poly(AS-alt-MIPOSS-NHBu)] copolymers through facile free radical copolymerizations using azobisisobutyronitrile as the initiator and tetrahydrofuran as the solvent. A poly(4-hydroxystyrene-alt-2-aminobutyl maleimide isobutyl POSS) [poly(HS-alt-MIPOSS-NHBu)] copolymer was prepared through acetoxyl hydrazinolysis of poly(AS-alt-MIPOSS-NHBu). We employed H-1, C-13, and Si-29 nuclear magnetic resonance spectroscopy; Fourier transform infrared spectroscopy; differential scanning calorimetry; and photoluminescence spectroscopy to investigate the structures and the thermal and optical properties of the monomers and novel POSS-containing alternating copolymers. Intramolecular hydrogen bonding between the amino and dihydrofuran-2,5-dione group and clustering of the locked C = O groups from the POSS nanoparticles in the MIPOSS-NHBu units restricted the intramolecular motion of the polymer chain, causing it to exhibit strong light emission. As a result, the MIPOSS-NHBu monomer and the poly(AS-alt-MIPOSS-NHBu) copolymer both have potential applicability in the detection of metal ions with good selectivity.
Damage detection of structures with detrended fluctuation and detrended crosscorrelation analyses
(2017-03-01)
Lin, Tzu-Kang
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Fajri, Haikal
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土木工程學系
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Department of Civil Engineering
Recently, fractal analysis has shown its potential for damage detection and assessment in fields such as biomedical and mechanical engineering. For its practicability in interpreting irregular, complex, and disordered phenomena, a structural health monitoring (SHM) system based on detrended fluctuation analysis (DFA) and detrended cross-correlation analysis (DCCA) is proposed. First, damage conditions can be swiftly detected by evaluating ambient vibration signals measured from a structure through DFA. Damage locations can then be determined by analyzing the cross correlation of signals of different floors by applying DCCA. A damage index is also proposed based on multi-scale DCCA curves to improve the damage location accuracy. To verify the performance of the proposed SHM system, a four-story numerical model was used to simulate various damage conditions with different noise levels. Furthermore, an experimental verification was conducted on a seven-story benchmark structure to assess the potential damage. The results revealed that the DFA method could detect the damage conditions satisfactorily, and damage locations can be identified through the DCCA method with an accuracy of 75%. Moreover, damage locations can be correctly assessed by the damage index method with an improved accuracy of 87.5%. The proposed SHM system has promising application in practical implementations.
Is carotid sonography a useful tool for predicting functional capabilities in ischemic stroke patients following carotid artery stenting?
(2017-03-01)
Lin, Chih-Ming
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Su, Jian-Chi
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Chang, Yu-Jun
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Liu, Chi-Kuang
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Lu, Henry Horng-Shing
Carotid stenosis is a major cause of stroke and timely intervention with stenting manipulation can significantly reduce the risk of secondary stroke. The impact of stenting procedures on patient functional capabilities has not yet been explored. The primary aim of this study was to examine associations between periprocedural carotid sonography parameters and post-treatment functional capabilities in stroke patients. Sixty-seven patients who received carotid stenting at 1 angiography laboratory were included. Prestenting and poststenting carotid duplex data were recorded and resistance index (RI) differences at various carotid system locations were compared. The modified Rankin Scale (mRS) was used to assess functional capability. All of the studied parameters were analyzed by SPSS (version 16.0, SPSS Inc, Chicago, IL). Following stenting, mRS scores improved (n= 44) or remained stationary (n= 23). Net contralateral internal carotid artery (ICA) RI for patients with improved mRS was lower compared to that for patients with stationary mRS (median= 0.040 vs 0.11; P= 0.003). The contralateral common carotid artery RI before and after stenting differed significantly (P < 0.050) in both. The ipsilateral ICA RI differed (P < 0.050) only in patients with improved mRS. The difference in mean transit time, Barthel index, net ipsilateral ICA RI, net contralateral external carotid artery RI, postipsilateral common carotid artery RI, and postipsilateral ICA RI differed significantly between different baseline stroke severity groups (P < 0.050). Carotid artery stenting improved physical function in a proportion of ischemic stroke patients with carotid stenosis. Carotid ultrasound is a useful assessment tool to predict likely functional outcomes following carotid artery stenting.
BUERGER'S EXERCISE EFFECTS ON IMPROVEMENT OF DORSAL FOOT SKIN CIRCULATION ASSESSED BY WIRELESS NEAR-INFRARED SPECTROSCOPE IN PATIENTS WITH VASCULPATHIC DIABETES FOOT ULCERS: A COHORT PROSPECTIVE STUDY
(2017-03-01)
Chang, Cheng Chang
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Lin, Bor-Shyh
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Li, Jhe-Ruei
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Chen, Min-Ling
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Chen, Mei-Yen
腦波控制式睡眠環境輔助系統及其方法
(2017-03-01)
林進燈
;
黃志勝
;
柯立偉
;
王俞凱
本發明係揭露一種腦波控制式睡眠環境輔助系統及其方法，其主要係利用一組腦波感測器來感測收集複數腦波訊號，並利用控制電路判斷腦波訊號是否為大腦睡眠狀態，並根據大腦睡眠狀態產生對應之指示訊號，使電源控制器可根據指示訊號對應產生一控制訊號來操控空氣調節裝置調整之溫度與溼度或是其他家電設備，以自動調控整個睡眠環境，進而有效提高睡眠品質。另外，本發明亦可利用腦波訊號或是預設起床時間搭配家電設備之控制，來達到喚醒使用者起床之目的者。
Plateau-Rayleigh Instability Morphology Evolution (PRIME): From Electrospun Core-Shell Polymer Fibers to Polymer Microbowls
(2017-03-01)
Chiu, Yu-Jing
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Tseng, Hsiao-Fan
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Lo, Yu-Ching
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Wu, Bo-Hao
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Chen, Jiun-Tai
Electrospun core-shell fibers have great potentials in many areas, such as tissue engineering, drug delivery, and organic solar cells. Although many core-shell fibers have been prepared and studied, the morphology transformation of core-shell fibers have been rarely studied. In this work, the morphology evolution of electrospun core-shell polymer fibers driven by the Plateau-Rayleigh instability is investigated. Polystyrene/poly(methyl methacrylate) (PS/PMMA) core-shell fibers are first prepared by using blend solutions and a single axial electrospinning setup. After PS/PMMA core-shell fibers are annealed on a PS film, the fibers undulate and sink into the polymer film, forming core-shell hemispheres. The evolution process, which can be observed in situ by optical microscopy, is mainly driven by achieving lower surface and interfacial energies. The morphologies of the transformed structures can be confirmed by a selective removal technique, and polymer microbowls can be obtained.
Evaluation of loading sequences on testing capacity of concentrically braced frame structures
(2017-03)
Chen, Chui-Hsin
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Hu, Huai-Kuo
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土木工程學系
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Department of Civil Engineering
Static cyclic loading tests are commonly used to evaluate the seismic capacity of a structure. However, different loading sequences would result in different structural behavior. To quantify the effects of loading sequences on the structural capacity, we investigate the experimental behavior of braces in concentrically braced frames (CBF) under different loading sequences. The variables for testing program includes two different pipe sections (different slenderness as well) and three loading protocols, namely, loading sequence for beam-to-column moment connections (151), loading sequence for link-to-column connections (LS2) and proposed loading sequence for CBF structures (153). After tests, we compare the critical performance parameters of different specimens including the failure modes, maximum deformation, cumulative energy, etc. Test results show that the specimens fracture at different deformation stages under different loading sequences. The specimens accumulate energy the fastest under LS1. The maximum cumulative energy is less correlated to the loading sequences. The test results also show that the rate of cumulative deformation under LS1 is too fast for CBF structures; the rate under 152, on the contrary, is a little slow for CBF structures. LS3 is more suitable for braces in regard to failure modes, cumulative deformation rate, cumulative energy rate, and deformation amplitude. (C) 2016 Elsevier Ltd. All rights reserved.
Determining radial efficiency with a large data set by solving small-size linear programs
(2017-03-01)
Chen, Wen-Chih
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Lai, Sheng-Yung
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工業工程與管理學系
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Department of Industrial Engineering and Management
This paper presents a new algorithm for determining radial efficiency with a large data set by using small-size linear programs (LPs). Instead of trying to "reduce" the size of individual LPs, the proposed algorithm attempts to "control" the size of individual LPs, e.g., no more than 100 data points each time while maintaining the solution quality. The algorithm is specifically designed to address the problem of LP size limitation. From the empirical results, we conclude that the proposed algorithm can converge within a reasonable number of iterations without incurring extra computation time and has savings of up to 60 % of the benchmarks when the data set contains 15,000 points.
利用腦波進行注意力反饋訓練之方法及其系統
(2017-03-01)
林進燈
;
王俞凱
;
呂紹瑋
;
陳世安
一種利用腦波進行注意力反饋訓練之方法及其系統，其係透過一顯示模組播放互動場景給使用者觀看，以產生視覺刺激；再由使用者根據視覺刺激之不同與場景互動，同時利用一腦波量測模組記錄下使用者之腦波訊號；之後，將此腦波訊號透過漸進式演化處理，以擷取處理後之腦波訊號與儲存之標準訊號進行比對與匹配，若匹配成功，則使用者可透過系統給予的回饋瞭解自己在此互動場景中因專注力的提昇而完成場景互動，反之則反饋使用者更須提昇其專注力與場景進行互動，使其基於此種注意力反饋方法及系統提升其專注力。
Enhanced Deployment Algorithms for Heterogeneous Directional Mobile Sensors in a Bounded Monitoring Area
(2017-03-01)
Lin, Ting-Yu
;
Santoso, Hendro Agus
;
Wu, Kun-Ru
;
Wang, Gui-Liu
;
電機工程學系
Good deployment of sensors empowers the network with effective monitoring ability. Different from omnidirectional sensors, the coverage region of a directional sensor is determined by not only the sensing radius (distance), but also its sensing orientation and spread angle. Heterogeneous sensing distances and spread angles are likely to exist among directional sensors, to which we refer as heterogeneous directional sensors. In this paper, we target on a bounded monitoring area and deal with heterogeneous directional sensors equipped with locomotion and rotation facilities to enable the sensors self-deployment. Two Enhanced Deployment Algorithms, EDA-I and EDA-II, are proposed to achieve high sensing coverage ratio in the monitored field. EDA-I leverages the concept of virtual forces (for sensors movements) and virtual boundary torques (for sensors rotations), whereas EDA-II combines Voronoi diagram directed movements and boundary torques guided rotations. EDA-I computations can be centralized or distributed that differ in required energy and execution time, whereas EDA-II only allows centralized calculations. Our EDA-II outperforms EDA-I in centralized operations, while EDA-I can be adapted into a distributed deployment algorithm without requiring global information and still achieves comparably good coverage performance to its centralized version. To the best of our knowledge, this is perhaps the first work to employ movements followed by rotations for sensors self-deployment. Performance results demonstrate that our enhanced deployment mechanisms are capable of providing desirable surveillance level, while consuming moderate moving and rotating energy under reasonable execution time.