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A built-in self-test (BIST) circuit has been designed to test setup and hold times of I/O registers or buffers for memory interfaces. This method enables independent testing of setup and hold times without using an external teste...
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A built-in self-test (BIST) circuit has been designed to test setup and hold times of I/O registers or buffers for memory interfaces. This method enables independent testing of setup and hold times without using an external tester, except to generate the reference clock. The circuit uses a delay-locked loop (DLL) to generate delayed clocks. It has been implemented with a 0.18-$ mu$m TSMC process (CM018). The accuracy in delay generation is within 40 ps, for delay measurements ranging from 300 to 700 ps. In order to achieve high accuracy, the BIST circuit requires frequency adjustment during test, combined with averaging over multiple test cycles. To do this in an efficient manner, the DLL in the BIST circuit has been designed for a wide lock range, from 150 to 400 MHz, and achieves lock in less than 0.05 $ mu$s. This paper describes the design in detail and evaluates its performance, together with test time and accuracy. It also shows how to use a low-resolution DLL to achieve high accuracy through frequency adjustment and averaging over multiple test cycles.
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The effective interface potential is derived fbr a superconducting layer attached to a wall. The expression applies to the neighborhood of a continuous wetting or delocalization transition, which exists for type I superconductors ...
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The effective interface potential is derived fbr a superconducting layer attached to a wall. The expression applies to the neighborhood of a continuous wetting or delocalization transition, which exists for type I superconductors with a negative extrapolation length. From this potential a number of Features can be easily derived, such as the locus of the phase transition and the critical exponents. Whereas the order parameter exponent is universal, other exponents, like the susceptibility exponent, are not. [References: 13]
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The paper addresses the integration architecture (I-concept) between a terrestrial technology—TETRA (TErrestrial Trunked Radio)—and satellite systems. This approach, that enhances and harmonises the features of both technologies...
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The paper addresses the integration architecture (I-concept) between a terrestrial technology—TETRA (TErrestrial Trunked Radio)—and satellite systems. This approach, that enhances and harmonises the features of both technologies, could provide an interesting contribution to the effectiveness of the International Mobile Telecommunications-Advanced (IMT-A) and, hence, to the 4G vision. TETRA can represent an interesting building block of an integrated network devoted to both civil and military scenarios; it meets the “suitable technological capability” requirement for integration, because it represents a consolidated terrestrial technology that can be trusted, hence focusing the integration effort on the definition, design and implementation of proper interfaces. System architectures are here proposed referring to short, medium term and long term scenarios.
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The paper addresses the integration architecture (I-concept) between a terrestrial technology - TETRA (TErrestrial Trunked Radio) - and satellite systems. This approach, that enhances and harmonises the features of both technologi...
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The paper addresses the integration architecture (I-concept) between a terrestrial technology - TETRA (TErrestrial Trunked Radio) - and satellite systems. This approach, that enhances and harmonises the features of both technologies, could provide an interesting contribution to the effectiveness of the International Mobile Telecommunications-Advanced (IMT-A) and, hence, to the 4G vision. TETRA can represent an interesting building block of an integrated network devoted to both civil and military scenarios; it meets the "suitable technological capability" requirement for integration, because it represents a consolidated terrestrial technology that can be trusted, hence focusing the integration effort on the definition, design and implementation of proper interfaces. System architectures are here proposed referring to short, medium term and long term scenarios.
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One of the most challenging requirements in a solid rocket motor (SRM) is the integrity of the charge structure which is a multilayer adhesive joint involving the propellant, liner, and insulation. The propellant/liner/insulation ...
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One of the most challenging requirements in a solid rocket motor (SRM) is the integrity of the charge structure which is a multilayer adhesive joint involving the propellant, liner, and insulation. The propellant/liner/insulation interface is considered to be the weakest part of the whole structure. This interface has some of the usual features of an adhesively bonded interface, as well as its own special characteristics: the co-cured process, ingredient migration between interfaces, and complicated damage mechanisms. We give a technical and critical review of the past 50 years of existing research on many aspects of the propellant/liner/insulation interface in terms of the adhesive properties and adhesive mechanisms, ingredients migration, damage determination, and fracture analysis. To present a comprehensive outline of this interface we also clarify some remaining problems which should be addressed in the future. With significant improvements in the theoretical and experimental studies of the propellant/liner/insulation interface, the problem of integrity failure of the charge structure in SRM will be well resolved.
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This paper presents the design and characteristics of a five-fingered haptic interface robot named HIRO III. The aim of the development of HIRO III is to provide a high-precision three-directional force at the five human fingertip...
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This paper presents the design and characteristics of a five-fingered haptic interface robot named HIRO III. The aim of the development of HIRO III is to provide a high-precision three-directional force at the five human fingertips. HIRO III consists of a 15-degrees-of-freedom (DOF) haptic hand, a 6-DOF interface arm, and a control system. The haptic interface, which consists of a robot arm and hand, can be used in a large workspace and can provide multipoint contact between the user and a virtual environment. However, the following problems peculiar to a multi-DOF robot have arisen: a large amount of friction, a backlash, and the presence of many wires for many motors and sensors. To solve these problems, a new mechanism and a wire-saving control system have been designed and developed. Furthermore, several experiments have been carried out to investigate the performance of HIRO III. These results show the high-precision force display and great potential of HIRO III.
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Since conventional audio-video teleconferencing systems have reached their limits, the needs of integrating new sensations to improve users' telecommunication experience are growing. Haptics, the sense of touch, which includes han...
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Since conventional audio-video teleconferencing systems have reached their limits, the needs of integrating new sensations to improve users' telecommunication experience are growing. Haptics, the sense of touch, which includes handshake, comforting hug, encouraging pat, and other physical contacts, is important to interpersonal communication, as it allows people to express and receive intimate affection, intention or emotion efficiently. Motivated by some haptic telecommunication softwares, this paper presents an innovative webcam-based touchscreen to further increase people's degree of immersion with the haptic video chat system at a more reasonable price. With our webcam-based touchscreen, the user could directly use his/her bare hand to touch the image of the person who he/she is chatting with, instead of controlling a haptic device as the medium to realize indirect touch. This paper also gives details of the touchscreen method and our proposed mathematical models for touch position calculation. Experimental results show that our system is accurate and robust, while maintaining high compatibility with conventional audio-video teleconferencing systems for combination. With our haptic jacket, the passive user can feel the touch of the active user at the right position. Finally, we draw the conclusions and talk about future work.
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