Browsing by Author "Hu, CH"

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A multi-user visual object-oriented programming environment
(1998)
Hu, CH
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Wang, FJ
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資訊工程學系
;
Department of Computer Science
Software systems are growing larger and more complex. The development of a large-scale software system usually requires the collaboration of multiple developers. This paper addresses several desirable features of a practical multi-user, visual object-oriented programming environment (mVOOPE) whose constituent components may be distributed over a long distance, unreliable communication environment such as the Internet. By incorporating three design rationales, more local processing, compact remote communication, and multithreaded collaboration, our mVOOPE makes a trade-off between performance and consistency requirements. The mVOOPE provides programming supports with two aspects: visual programming for object-oriented languages and collaborative programming for incremental software development. So far a window-based environment prototype, developed with Visual C++, executes on multiple PCs connected by the network.
A wireless video relay system at 28 GHz
(2001)
Hu, CH
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Wu, HL
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Chang, CY
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Chung, SJ
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電信工程研究所
LMDS (Local Multipoint Distribution Service) system can offer subscribers variety of one-way or two-way broadband services, such as video programming distribution, high speed data transmission, and wireless local loop telephony. LMDS centered around the 28 GHz band is the fastest, most flexible and economical broadband network that can be developed today. From last year, NCTU (National Chiao Tung University) was engaged in a four-year project, co-sponsored by the Ministry of Education and National Science Council, ROC, investigating the advanced millimeter-wave circuits and systems. Part of the work is to be implemented on the LMDS system as a platform. This paper presents some of the preliminary results.
An exponential-folds design of a charge pump styled DC/DC converter
(2004)
Chang, LK
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Hu, CH
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電控工程研究所
;
Institute of Electrical and Control Engineering
A charge pump styled DC/DC converter utilizing the exponential-folds structure and the pumping gain increase (PGI) circuit with high voltage transfer efficiency is proposed in this paper. A PGI circuit used in the linear DC/DC converter is proposed to solve the threshold voltage problem and limitation of the diode-con figured output stage so that the boosted output voltage increases more linearly versus the pumping stage number. With the exponential-folds structure, fewer voltage pump stages are needed to obtain the higher output voltage and further improve the voltage pumping gain. Especially, this design still has good efficiency with low input supply voltage such as one battery cell.
Constructing a toolset for software maintenance with OOAG
(1998)
Hu, CH
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Yang, JT
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Wang, FJ
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Chu, WC
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資訊工程學系
This paper presents a model called object-oriented attribute grammar (OOAG) that can be used to construct a toolset for software maintenance. The kernel of OOAG consists of two inter-related parts: a model-view-shape (MVS) application framework and an AG++, an object-oriented extension to traditional AGs. By combining compositional and generative techniques seamlessly, OOAG preserves both advantages introduced by respective OO and AG models, such as rapid prototyping, reusability, extensibility, and incrementality. So far, a toolset prototype consisting of a number of programming and maintenance tools were implemented using OOAG on the Windows environment. The editors developed can be used to construct programs by specifying the associated flow information in explicit (visual) or implicit (textual) ways, while the (incremental) maintenance tools, such as DU/UD tools and a program slicer, can help analyze incomplete program fragments to locate and inform the user of useful information.
Constructing an integrated visual programming environment
(1998-06-01)
Hu, CH
;
Wang, FJ
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資訊工程學系
;
Department of Computer Science
This paper presents an object-oriented architecture, called the Model-View-Shape (MVS) architecture, for constructing an Integrated Visual Programming Environment (IVPE), whose constituent tools deal with (fine-grained) language semantics, as well as a mass of graphics-drawing activities. This architecture enforces a layered and loosely-coupled structure, so that the user-interface part of components may be more independent, maintainable, and reusable than those proposed in the original model-view-controller architecture. An MVS class hierarchy, systematically constructed using C++, can be reused and extended with new semantics to rapidly develop new tools for an existing IVPE, or even an IVPE supporting more than one language, The present editors developed can be used to construct programs by specifying the associated flow information in explicit (visual) or implicit (textual) ways, while the (incremental) flow analysers can help analyse incomplete program fragments to locate and inform the user of possible errors or anomalies during programming. (C) 1998 John Wiley & Sons, Ltd.
Constructing flow-based tools with generative and compositional techniques
(2000-04-01)
Yang, JT
;
Wang, FJ
;
Chu, WC
;
Hu, CH
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資訊科學與工程研究所
In this paper, a model called object-oriented attribute grammar (OOAG), which combines both compositional and generative techniques, is presented to effectively construct flow-based tools that deal with fine-grained language semantics as well as a mass of graphics-drawing activities. OOAG, which consists of two interrelated parts: a model-view-shape (MVS) class framework and an AG++, an object-oriented extension to traditional AGs, is intended to preserve both advantages introduced by respective OO and AG models, such as rapid prototyping, reusability, extensibility, incrementality, and applicability. So far, a flow-based editor associated with two flow-analyzer prototypes, DU/UD tools and a program slicer, have been implemented using OOAG on the Windows environment. Our flow-based editor can be used to construct programs by specifying the associated flow information in a visual way, while (incremental) flow analyzers incorporated into the editor can help analyze incomplete program fragments to locate and inform the user of possible errors or anomalies during programming.
Continuous and precise work function adjustment for integratable dual metal gate CMOS technology using Hf-Mo binary alloys
(2005-06-01)
Li, TL
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Hu, CH
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Ho, WL
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Wang, HCH
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Chang, CY
We demonstrate for the first time a continuous and almost linear work function adjustment between 3.93 and 4.93 eV using HfxMo(1-x) binary alloys deposited by co-sputtering. In view of the process integration, dual work function metal gate technology using Mo and HfxMo(1-x) formed by metal intermixing was proposed. Work function values were verified to be a function of the thickness ratio and accurate work function adjustment can be possible. Furthermore, one can be allowed to get around the thermal stability issue by choosing an appropriate total metal thickness corresponding to the thermal budget subsequent to gate deposition, since the thermal budget required for metal intermixing depends on the total metal thickness.
Dielectric and barrier properties of spin-on organic aromatic low dielectric constant polymers FLARE and SiLK
(2001-06-01)
Wu, ZC
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Shiung, ZW
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Wu, RG
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Liu, YL
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Wu, WH
This work investigates the dielectric and barrier properties of two species of organic aromatic low dielectric constant (low-k) polymers, namely, FLARE and SiLK. Experimental results indicate that both of the low-k polymers exhibit acceptable thermal stability with respect to a thermal annealing at 400 degreesC for 8 h in an N-2 ambient. Moreover, they show a good dielectric barrier property against Cu penetration under bias-temperature stressing (BTS) at 150 degreesC with an applied effective field of 0.8 MV/cm. Nevertheless, an anomalous instability of the capacitance-voltage curve was observed for the first time under BTS. This finding is explained by the proposed model of stress induced dielectric polarization charges within these organic aromatic polymers. The polarization instability may seriously degrade the long term reliability of circuit operations. (C) 2001 The Electrochemical Society.
High efficiency MOS charge pumps based on exponential-gain structure with pumping gain increase circuits
(2006-05-01)
Chang, LK
;
Hu, CH
;
電控工程研究所
;
Institute of Electrical and Control Engineering
Novel MOS charge pumps utilizing an exponential-gain structure and pumping gain increase (PGI) circuits with high voltage transfer efficiency to generate boosted output voltages are described. By using the PGI circuits, the threshold voltage problem of the MOSFET used as a switch is solved, and the limitation of the diode-configured output stage is removed. Thus, the boosted output voltage increases linearly as compared to the pumping stage number. An exponential-gain structure is also presented as a further application of the PGI circuit. By using this structure, fewer voltage pump stages are needed to obtain the required output voltage. For 1.5-V supply voltage operation, a four-time series (1.5 V-to-6 V) is demonstrated using the new techniques. Simulation and experimental results have shown that this design has good efficiency with a low-input supply voltage such as a one battery cell.
Towards a practical visual object-oriented programming environment: Desirable functionalities and their implementation
(1999-07-01)
Hu, CH
;
Wang, FJ
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資訊科學與工程研究所
;
Institute of Computer Science and Engineering
The ultimate goal of a programming environment is to help simplify the software development process. For an object-oriented language, a visual (object-oriented) program ming environment (VOOPE) must at least satisfy four essential requirements to meet this goal: interactivity: integration, incrementality, and intelligence. In this study, object-oriented techniques were systematically applied to construct such a VOOPE. On the other hand, some characteristics of object-oriented languages, such as inheritance and polymorphism, may themselves be barriers to understanding, maintaining, and even constructing object-oriented programs. To solve, or at least alleviate, this problem, a language-based editing process has been designed and incorporated into our VOOPE. This process contains two key elements: syntax-directed editing facilities and an in-place editing assistant, which facilitate object-oriented program development by providing useful programming guidance and by reducing the number of potential programming errors. We have so far developed a window-based environment prototype using Visual C++ and the Microsoft Foundation Classes library.