Browsing by Issue Date, starting with "2019-08-02"

Now showing 1 - 20 of 7086

Modeling team performance from the perspective of politics and ethical leadership
(2019-08-02)
Lin, Chieh-Peng
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Liu, Na-Ting
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Chiu, Chou-Kang
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Chen, Kuang-Jung
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Lin, Ni-Chen
Purpose The purpose of this paper is to develop and test a model of team performance by applying social exchange and social capital perspectives in a single model setting. It hypothesizes that team performance is indirectly affected by politics through leader-member capitalization (LMC) and by ethical leadership through leader-member exchange (LMX). Meanwhile, team identification is hypothesized to moderate the relationships between politics and LMC and between ethical leadership and LMX. Design/methodology/approach The hypotheses of this study were empirically tested using a survey of work teams from the banking and insurance industry in Taipei, Taiwan. Findings The relationship between team performance and ethical leadership is fully mediated by LMX, while the indirect relationship between team performance and politics is mediated via both LMC and LMX. Team identification positively moderates the relationship between ethical leadership and LMX. Originality/value This study is one of the few to examine the mediating roles of LMC and LMX simultaneously in team performance development. This study provides several key findings that complement the existing literature by evaluating fresh associations among LMC, LMX and their determinants and moderator.
The Effects of Different Dynamic Culture Systems on Cell Proliferation and Osteogenic Differentiation in Human Mesenchymal Stem Cells
(2019-08-02)
Tsai, Hsiou-Hsin
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Yang, Kai-Chiang
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Wu, Meng-Huang
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Chen, Jung-Chih
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Tseng, Ching-Li
The culture environment plays an important role for stem cells' cultivation. Static or dynamic culture preserve differential potentials to affect human mesenchymal stem cells' (hMSCs) proliferation and differentiation. In this study, hMSCs were seeded on fiber disks and cultured in a bidirectional-flow bioreactor or spinner-flask bioreactor with a supplement of osteogenic medium. The hMSCs' proliferation, osteogenic differentiation, and extracellular matrix deposition of mineralization were demonstrated. The results showed that the spinner flask improved cell viability at the first two weeks while the bidirectional-flow reactor increased the cell proliferation of hMSCs through the four-week culture period. Despite the flow reactor having a higher cell number, a lower lactose/glucose ratio was noted, revealing that the bidirectional-flow bioreactor provides better oxygen accessibility to the cultured cells/disk construct. The changes of calcium ions in the medium, the depositions of Ca2+ in the cells/disk constructs, and alkaline phosphate/osteocalcin activities showed the static culture of hMSCs caused cells to mineralize faster than the other two bioreactors but without cell proliferation. Otherwise, cells were distributed uniformly with abundant extracellular matrix productions using the flow reactor. This reveals that the static and dynamic cultivations regulated the osteogenic process differently in hMSCs. The bidirectional-flow bioreactor can be used in the mass production and cultivation of hMSCs for applications in bone regenerative medicine.
Linking corporate sustainability and innovation in supply chain management - evidence of a Taiwan leading glass recycling company
(2019-08-03)
Lim, Sirirat Sae
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Sonko, Lamin K.
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科技管理研究所
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Institute of Management of Technology
This empirical study presents a combination of insights from corporate sustainability practices, supply chain management, and innovation literature, and a case study to discover new understandings on factors influencing firms to incorporate sustainable innovation initiatives into their supply chain practices. There is an apparent lack of literature in this field due to its modernity and evolving nature. Also, there is a lack of insights into how firms could translate sustainable innovation initiatives into practice. This study addresses this gap by examining a successful glass recycling company through the lenses of sustainable innovation context and the Global Reporting Initiative G3 Guideline framework. Primary data are collected through observations and in-depth interview before it is coded and analysed using nVivo. The findings show that sustainable innovation practices are mainly directed at improving the technological processes, resource sharing, and reduction of production cost among supply chain partners. A conceptual sustainable innovation framework is also proposed. This study contributes to sustainable innovation literature by providing insights into the evaluation of a firm's innovative sustainability efforts.
Tunable diameter and spacing of double Ge quantum dots using highly-controllable spacers and selective oxidation of SiGe
(2019-08-05)
Huang, Tsung-Lin
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Peng, Kang-Ping
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Chen, Ching-Lun
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Lin, Horng-Chih
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George, Tom
We report the novel tunability of the diameters and spacings of paired Ge double quantum dots (DQDs) using nano-spacer technology in combination with selective oxidation of Si0.85Ge0.15 at high temperature. Pairs of spherical-shaped Ge QDs were formed by the selective oxidation of poly-SiGe spacer islands at each sidewall corner of the nano-patterned Si3N4/poly-Si ridges. The diameters of the Ge spherical QDs are essentially determined by geometrical conditions (height, width, and length) of the nano-patterned spacer islands of poly-SiGe, which are tunable by adjusting the process times of deposition and etch back for poly-SiGe spacer layers in combination with the exposure dose of electron-beam lithography. Most importantly, the separations between the Ge DQDs are controllable by adjusting the widths of the poly-Si/Si3N4 ridges and the thermal oxidation times. Our self-organization and self-alignment approach achieved high symmetry within the Ge DQDs in terms of the individual QD diameters as well as the coupling barriers between the QDs and external electrodes in close proximity.
Coumarin-based Hg2+ fluorescent probe: Fluorescence turn-on detection for Hg2+ bioimaging in living cells and zebrafish
(2019-08-05)
Chen, Chong-Guang
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Vijay, Natarajan
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Thirumalaivasan, Natesan
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Velmathi, Sivan
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Wu, Shu-Pao
The need in developing fluorescent probes for trace metal ion detection in biological samples has been an important issue. Herein, a reaction-based fluorescent probe PIC containing a perimidine moiety was designed and synthesized for Hg2+ detection. The probe can selectively distinguish Hg2+ with 42-fold fluorescent enhancement from the other metal ions at physiological pH. This probe can detect Hg2+ with the detection limit of 1.08 mu M. The sensor PIC can be applied to real-time detection of Hg2+ in cells with blue emission. (C) 2019 Elsevier B.V. All rights reserved.
Angular color variation in micron-scale light-emitting diode arrays
(2019-08-05)
Yang, Shu-Mei
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Wang, Po-Hsun
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Chao, Chia-Hsin
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Chu, Chun-Wen
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Yeh, Yin-Tien
A simulation scheme was developed to explore the light distribution of full-color micron-scale light-emitting diode (LED) arrays. The influences of substrate thickness, patterning, and cutting angle of the substrate on several important features, such as light field pattern, light extraction efficiency, and color variation, were evaluated numerically. An experiment was conducted; the results were consistent with simulation results for a 225 x 125 mu m(2) miniLED and those for an 80 x 80 mu m(2) microLED. Based on the simulation results, the light extraction efficiency of LED devices with a substrate increases by 67.75% over the extraction efficiency of those without a substrate. The light extraction efficiency of LED devices with a substrate increases by 113.55% when an additional patterned design is used on green and blue chips. The calculated large angle Delta u'v' can be as low as 0.015 for miniLED devices. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
Plastic anisotropy and deformation-induced phase transformation of additive manufactured stainless steel
(2019-08-05)
Chae, Hobyung
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Huang, E-Wen
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Jain, Jayant
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Wang, Huamiao
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Woo, Wanchuck
Plastic anisotropy and deformation-induced phase transformation of additively manufactured (AM) stainless steels were investigated via in-situ neutron diffraction, electron backscatter diffraction, metallography, and fractography. Two types of tensile specimens were manufactured: (1) One sample was vertically fabricated with its tensile axis parallel to the z-direction (AM-V), (2) The other sample was horizontally fabricated with its tensile axis perpendicular to the z-direction (AM-H). A commercial 15-5PH stainless steel (CA) was used for comparison. AM steel revealed enhanced yield strength, tensile strength, and uniform elongation over CA, which was mainly due to grain refinement and transformation induced plasticity (TRIP). Different onsets of strain nonlinearity between AM-V and AM-H were closely related to martensitic phase transformation. Stresses estimated from lattice strains measured by neutron diffraction matched well with the applied stress-strain curves. After plastic deformation, voids were formed and congregated near the solidified line where fine grains were populated. Higher dislocation density was observed in the fine grain zone, and lower density was shown in the relatively coarse grain zone. AM steels exhibited significant anisotropic fracture behavior in terms of loading direction. In contrast to isotropic failure for CA and AM-V, AM-H revealed anisotropic failure with elliptical formation of the fracture feature. The fracture surface of AM-H possessed many secondary cracks propagating perpendicular to the building direction. The occurrence of secondary cracks in AM-H resulted in rapid load drop during tensile loading after necking.
Interplay of carriers and deep-level recombination centers of 275-nm light-emitting diodes - Analysis on the parasitic peaks over wide ranges of temperature and injection density
(2019-08-05)
Wu, Tingzhu
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Lin, Yue
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Peng, Zhangbao
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Chen, Huashan
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Shangguan, Zhibin
The low luminance efficiency, poor reliability and parasitic peaks have greatly limited the commercialization of deep ultraviolet (DUV) light-emitting diodes. Tasks of identifying the culprits of these deficits are of paramount importance but remains unaccomplished. We employ the full-range temperature (20 K - 300 K) measurement on 275-nm DUV devices that subjected to a 15-hour current-stress aging. The results suggest that the primary culprit of fast luminous decay is the proliferation of non-radiative centers. The origins of two main parasitic peaks are identified. The 310-nm peak is considered to solely come from deep-level radiative centers (DLRCs) that only dwell in the active region. Whereas, the 400-nm peak is proven to be dual-sources. One is related to the DLRCs in the active region, which only can be observed at very low currents; the other emerging at higher currents are associated with similar kinds of DLRCs located in the p-region, which only are excited when electrons overflow. This new discovery also demonstrates that a thorough investigation on the interplay among carriers and various types of defects should be conducted on the basis of the measurement that is taken under a wide temperature range, as well as under a proper forward voltage. This is to let the quasi-Fermi level shift across deep defect levels, the band-edge, and to over-band, whereby these recombination sites are exposed to deficit, moderate and saturated electron environment so that their natures can be well tested. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
A Vertical Flow Method for Sensitive Raman Protein Measurement in Aqueous Solutions
(2019-08-06)
Li, Shu-Chi
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Hiramatsu, Hirotsugu
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交大名義發表
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應用化學系
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應用化學系分子科學碩博班
Raman scattering is intrinsically faint. Raman spectroscopy would be more valuable with improvements in the signal detection efficiency. To improve the signal detection efficiency, we propose a vertical flow method, which is a derivative of the liquid core optical fiber technique employed for sensitive Raman signal detection. In the vertical flow method, the sample solution flows from a pinhole to prepare a liquid column wrapped with air and uses total reflection at the sample-air interface to confine the excitation beam and Raman signal. The Raman signal emerges from the pinhole for efficient collection. This method enhanced Raman signal intensity by up to 90 times. When measuring a bovine serum albumin aqueous solution, the limit of detection (LOD) was 0.029 +/- 0.003 mg mL(-1) (0.44 +/- 0.05 mu M). We discuss the signal enhancement factor dependence on several parameters in the vertical flow method. Our method provides a simple technique to improve Raman spectroscopy sensitivity using universal materials.
Designable Spectrometer-Free Index Sensing Using Plasmonic Doppler Gratings
(2019-08-06)
Lin, Fan-Cheng
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See, Kel-Meng
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Ouyang, Lei
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Huang, You-Xin
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Chen, Yi-Ju
Typical nanoparticle-based plasmonic index sensors detect the spectral shift of localized surface plasmon resonance (LSPR) upon the change of the environmental index. Therefore, they require broadband illumination and spectrometers. The sensitivity and flexibility of nanoparticle-based index sensors are usually limited because LSPR peaks are usually broad and the spectral position cannot be freely designed. Here, we present a fully designable index sensing platform using plasmonic Doppler gratings (PDGs), which provide broadband and azimuthal angle dependent grating periodicity. Different from LSPR sensors, PDG index sensors are based on the momentum matching between photons and surface plasmons via the lattice momentum of the grating. Therefore, the index change is translated into the variation of the in-plane azimuthal angle for photon-to-plasmon coupling, which manifests as directly observable dark bands in the reflection image. The PDG can be freely designed to optimally match the range of index variation for specific applications. In this work, we demonstrate PDG index sensors for large (n = 1.00-1.52) and small index variations (n = 1.3330-1.3650). The tiny and nonlinear index change of the water-ethanol mixture has been clearly observed and accurately quantified. Since the PDG is a dispersive device, it enables on-site and single-color index sensing without a spectrometer and provides a promising spectroscopic platform for on-chip analytical applications.
In Situ Analysis of Growth Behaviors of Cu2O Nanocubes in Liquid Cell Transmission Electron Microscopy
(2019-08-06)
Lin, Ya-Hsuan
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Chen, Jui-Yuan
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Chen, Fu-Chun
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Kuo, Ming-Yu
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Hsu, Yung-Jung
Metal oxides have attracted substantial attention over the years and are commonly used in the semiconductor industry because of their excellent physical and chemical properties. Among the various metal oxides, cuprous oxide (Cu2O) is regarded as a promising material. It is inexpensive, earth-abundant, and nontoxic; therefore, it can be used in catalysis, sensors, solar cells, and p-type semiconductors. However, the redox reaction of Cu2O is still uncertain. The size, morphology, and structure of Cu2O strongly influence its properties. In this work, we developed a new synthesis method of Cu2O that involves reducing the precursor by an electron beam without reducing agent. The growth process of Cu2O nanocubes was observed via in situ liquid cell transmission electron microscopy (in situ LCTEM). The nucleation kinetics, oscillating growth behavior, and redox reaction of the Cu2O nanocubes in the liquid phase were systematically studied. Cu2O exhibited a round shape at the beginning and transformed into a cubic shape afterward. Interestingly, the Cu2O nanocubes grew clearly under long-term observation; however, their diameters increased and fluctuated during the short-term observation. The electron beam not only stimulated the solution to reduce the nanocubes but also caused electron radiation effect to the nanocubes. During the Cu2O growth and dissolution, the cubic shape evolved with specific planes in the {100} family. Our direct observation sheds light on the preparation of Cu2O by a reduction method, extending the study of reaction kinetics and providing a new way to synthesize metal oxides.
Tail Fiber Protein-Immobilized Magnetic Nanoparticle-Based Affinity Approaches for Detection of Acinetobacter baumannii
(2019-08-06)
Bai, Yi-Ling
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Shahed-Al-Mahmud, Md.
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Selvaprakash, Karuppuchamy
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Lin, Nien-Tsung
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Chen, Yu-Chie
Acinetobacter baumannii (A. baumannii) strains are common nosocomial pathogens that can cause infections and can easily become resistant to antibiotics. Thus, analytical methods that can be used to rapidly identify A. baumannii from complex samples should be developed. Tail fiber proteins derived from the tail fibers of bacteriophages can recognize specific bacterial surface polysaccharides. For example, recombinant tail proteins, such as TF2 and TF6 derived from the tail fibers of bacteriophages phi AB2 and phi AB6, can recognize A. baumannii clinical isolates M3237 and 54149, respectively. Thus, TF2 and TF6 can be used as probes to target specific A. baumannii strains. Generally, TF2 and TF6 are tagged with a hexahistidine (His(6)) for ease of purification. Given that His(6) possesses specific affinity toward alumina through His(6)-Al chelation, TF2- and TF6-immobilized alumina-coated magnetic nanoparticles (Fe3O4@Al2O3 MNPs) were generated through chelation under microwave heating (power, 900 W) for 60 s in this study. The as-prepared TF2-Fe3O4@Al2O3 and TF6-Fe3O4@Al(2)O(3 )MNPs were used as affinity probes to trap trace A. baumannii M3237 and 54149, respectively, from sample solutions. Matrix-assisted laser desorption/ionization mass spectrometry capable of identifying bacteria on the basis of the obtained fingerprint mass spectra of intact bacteria was used as the detection tool. Results demonstrated that the current approach can be used to distinguish A. baumannii M3237 from A. baumannii 54149 by using TF2-Fe3O4@Al2O3 and TF6-Fe3O4@Al(2)O(3 )MNPs as affinity probes. Furthermore, the limits of detection of the current method for A. baumannii M3237 and 54149 are similar to 10(5) and similar to 10(4) cells mL(-1), respectively. The feasibility of using the developed method to selectively detect A. baumannii M3237 and 54149 from complex serum samples was demonstrated.
Synthesis of Free-Standing Flexible rGO/MWCNT Films for Symmetric Supercapacitor Application
(2019-08-06)
Kumar, Amit
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Kumar, Nagesh
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Sharma, Yogesh
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Leu, Jihperng
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Tseng, Tseung Yuen
Herein, we report a novel, simple, and cost-effective way to synthesize flexible and conductive rGO and rGO/MWCNT freestanding films. The effects of MWCNT addition on the electrochemical performance of rGO/MWCNT nanocomposite films are investigated in some strong base aqueous electrolytes, such as KOH, LiOH, and NaOH via three-electrode system. The supercapacitor behavior of the films is probed via cyclic voltammetry, galvanostatic charging-discharging, and electrochemical impedance spectroscopy. The structural and morphological studies of the films are performed by X-ray diffractometer, Raman spectrometer, surface area analyzer, thermogravimetric analysis, field emission scanning electron microscope and transmission electron microscope. The rGO/MWCNT film synthesized with 10 wt% MWCNTs (GP10C) exhibits high specific capacitance of 200 Fg(-1), excellent cyclic stability with 92% retention after 15,000 long cycle test, small relaxation time constant (similar to 194 ms), and high diffusion coefficient (7.8457 x 10(-9) cm(2) s(-1)) in 2 M KOH electrolyte. Furthermore, the symmetric supercapacitor coin cell with GP10C as both anode and cathode using 2 M KOH as electrolyte demonstrates high energy density of 29.4 Whkg(-1) and power density of 439 Wkg(-1) at current density 0.1 Ag-1 and good cyclic stability with 85% retention of the initial capacitance at 0.3 Ag-1 after 10,000 cycles. Such a high performance of the GP10C film in the supercapacitor can be ascribed to the large surface area and small hydration sphere radius and high ionic conductivity of K+ cations in KOH electrolyte.
WinProphet: A User-Friendly Pipeline Management System for Proteomics Data Analysis Based on Trans-Proteomic Pipeline
(2019-08-06)
Chen, Ching-Tai
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Ko, Chu-Ling
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Choong, Wai-Kok
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Wang, Jen-Hung
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Hsu, Wen-Lian
Protein and peptide identification and quantitation are essential tasks in proteomics research and involve a series of steps in analyzing mass spectrometry data. Trans-Proteomic Pipeline (TPP) provides a wide range of useful tools through its web interfaces for analyses such as sequence database search, statistical validation, and quantitation. To utilize the powerful functionality of TPP without the need for manual intervention to launch each step, we developed a software tool, called WinProphet, to create and automatically execute a pipeline for proteomic analyses. It seamlessly integrates with TPP and other external command-line programs, supporting various functionalities, including database search for protein and peptide identification, spectral library construction and search, data-independent acquisition (DIA) data analysis, and isobaric labeling and label-free quantitation. WinProphet is a standalone, installation-free tool with graphical interfaces for users to configure, manage, and automatically execute pipelines. The constructed pipelines can be exported as XML files with all of the parameter settings for reusability and portability. The executable files, user manual, and sample data sets of WinProphet are freely available at http://ms.iis.sinica.edu.tw/COmics/Software_WinProphet.html.
Dependence of the structure and orientation of VSS grown Si nanowires on an epitaxy process
(2019-08-07)
Chiang, Yi-Ting
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Chou, Yi
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Huang, Chang-Hsun
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Lin, Wei-Ting
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Chou, Yi-Chia
We investigated the vapor-solid-solid growth of Si nanowires from Ni silicides on Si(111), Si(110), and GaN substrates. The morphology and structures of Si on these substrates are distinct, and are dependent on substrate lattices and an epitaxy process during growth. The sidewall facets and epitaxy of silicides and Si were discussed. In addition, Si grown on GaN nanowires was investigated which led to the formation of branched nanowire structures. The Si nanowires/nanodots lie on the surface of GaN nanowires to maintain lower system energy. We manipulated the whole process in a UHV and studied the crystal growth of Si on different lattice substrates. Meanwhile, the process which occurred in a non-UHV led to less regularity on the NiSi2 crystal facets and interface epitaxy between NiSi2 and Si nanowires.
Effects of solvent molecules on hemi-bonded (CH3SH)(2)(+): infrared absorption of [(CH3SH)(2)-X](+) with X = H2O, (CH3)(2)CO, or NH3 and (CH3SH)(n)(+) (n=3-6)
(2019-08-07)
Xie, Min
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Tsai, Huei-Ru
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Fujii, Asuka
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Lee, Yuan-Pern
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交大名義發表
Three-electron two-center (3e-2c) hemi-bonds play important roles in the oxidation and electron transport of proteins and are implicated to be involved in some neurodegenerative diseases. Our previous investigations on infrared (IR) spectra of (CH3SH)(2)(+) using vacuum-ultraviolet photoionization, infrared dissociation, and time-of-flight detection have shown that (CH3SH)(2)(+) is (3e-2c)-bonded. To investigate the influence of the solvent molecules on the (3e-2c)-bonded (CH3SH)(2)(+) in a supersonic jet, we added H2O or (CH3)(2)CO or NH3 or (CH3SH)(n) (n = 1-4) to (CH3SH)(2)(+) and investigated their IR action spectra. The (3e-2c)-bonded (CH3SH)(2)(+) ion core was maintained when a molecule of H2O or (CH3)(2)CO or CH3SH binds, indicating that the ion core is more stable than the hydrogen bond, whereas the (3e-2c)-bond became broken by a NH3 molecule because the proton transfer led to a more stable hydrogen-bonded structure. The spectral features of the SH-stretching modes of (CH3SH)(n)(+) (n = 3-6) indicate that the (3e-2c)-bonded (CH3SH)(2)(+) ion core is maintained and the first two additional CH3SH are H-bonded to the free SH groups of the ion core. For larger clusters with n = 5 and 6, the additional solvent molecules likely bind to the first solvation shell. These results show also that the (3e-2c)-bonded S therefore S structure is more stable than the S therefore O and S therefore N structures in [(CH3SH)(2)-X](+) with X = H2O or (CH3)(2)CO or CH3SH or NH3.
Microstructures and electrical properties of zirconium doped barium cerate perovskite proton conductors
(2019-08-09)
Jhuang, Jhe-Wei
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Lee, Kan-Rong
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Lee, Sheng-Wei
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Chang, Jeng-Kuei
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Jang, Shian-Ching
In this work, we vary the Zr to Ce ratio to investigate the microstructures and electrical properties of zirconium doped barium cerates. The solid state reaction is used in synthesizing the BaCe0.8-xZrxY0.2O3 (X = 0.1-0.5). The electron backscatter diffraction (EBSD) is successfully applied to identify the crystal structure of the barium cerates. EBSD results indicate that all samples have the orthorhombic structure. Conductivity measurement results show that for temperatures below 700 degrees C, Zr-doped barium cerates have higher protonic conductivities than oxygen-ion/electron-hole conductivities. The protonic conductivity increases with the Zr content initially, but decreases after the Zr content is higher than 0.3. The protonic conductivity of BCZY0.3 reaches 8.8 mS/cm at 700 degrees C in dry hydrogen atmosphere. Stability test results show that, for stable operation in CO2 atmosphere, the Zr content in barium cerates should be greater than 0.2. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Symmetry of deterministic ratchets
(2019-08-13)
Rozenbaum, V. M.
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Shapochkina, I., V
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Teranishi, Y.
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Trakhtenberg, L., I
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物理研究所
We consider the overdamped motion of a Brownian particle in an unbiased force field described by a periodic function of coordinate and time. A compact analytical representation has been obtained for the average particle velocity as a series in the inverse friction coefficient, from which follows a simple and clear proof of hidden symmetries of ratchets, reflecting the symmetry of summation indices of the applied force harmonics relative to their numbering from left to right and from right to left. We revealed the conditions under which (i) the ratchet effect is absent; (ii) the ratchet average velocity is an even or odd functional of the applied force, whose dependences on spatial and temporal variables are characterized by periodic functions of the main types of symmetries: shift, symmetric, and antisymmetric, and universal, which combines all three types. These conditions have been specified for forces with those dependences of a multiplicative (or additive-multiplicative) and additive structure describing two main ratchet types, pulsating and forced ratchets. We found the fundamental difference in dependences of the average velocity of pulsating and forced ratchets on parameters of spatial and temporal asymmetry of potential energy of a particle for systems in which the spatial and temporal dependence is described by a sawtooth potential and a deterministic dichotomous process, respectively. In particular, it is shown that a pulsating ratchet with a multiplicative structure of its potential energy cannot move directionally if the energy is of the universal symmetry type in time; this restriction is removed in the inertial regime, but only if the coordinate dependence of the energy does not belong to either symmetric or antisymmetric functions.
Analytics-statistics mixed training and its fitness to semisupervised manufacturing
(2019-08-13)
Parashar, Parag
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Chen, Chun Han
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Akbar, Chandni
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Fu, Sze Ming
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Rawat, Tejender S.
While there have been many studies using machine learning (ML) algorithms to predict process outcomes and device performance in semiconductor manufacturing, the extensively developed technology computer-aided design (TCAD) physical models should play a more significant role in conjunction with ML. While TCAD models have been effective in predicting the trends of experiments, a machine learning statistical model is more capable of predicting the anomalous effects that can be dependent on the chambers, machines, fabrication environment, and specific layouts. In this paper, we use an analytics-statistics mixed training (ASMT) approach using TCAD. Under this method, the TCAD models are incorporated into the machine learning training procedure. The mixed dataset with the experimental and TCAD results improved the prediction in terms of accuracy. With the application of ASMT to the BOSCH process, we show that the mean square error (MSE) can be effectively decreased when the analytics-statistics mixed training (ASMT) scheme is used instead of the classic neural network (NN) used in the baseline study. In this method, statistical induction and analytical deduction can be combined to increase the prediction accuracy of future intelligent semiconductor manufacturing.
A Fluorographene-Based Synaptic Transistor
(2019-08-13)
Liu, Bo
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Hong, Ming-Chun
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Sahoo, Mamina
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Ong, Bin Leong
;
Tok, Eng Soon
Exploring brain-inspired synaptic devices has recently become a new focus of research in nanoelectronic communities. In this emerging field, incorporating 2D materials into three-terminal synaptic transistors has brought various advantages. However, achieving a stable and long-term weight-modulation in these synaptic transistors, which are typically based on interface charge storage, is still a challenge due to the nature of their spontaneous relaxation. The application of an atomically thin fluorographene layer into the synaptic junction region suppresses this issue and improves the efficiency, tunability, and symmetry of the synaptic plasticity as well as establishing a stable weight-regulation paradigm. These unique properties can be attributed to the dipolar rotation of C-F in fluorographene. To obtain a better physical understanding, a vacancy-dependent C-F dipolar rotation model is proposed and supported by hysteresis analysis and density functional theory calculations. As proposed and demonstrated, the unique fluorographene-based synaptic transistor may be a promising building block for constructing efficient neuromorphic computing hardware.