13,819 research outputs found
Effects of Length and Diameter of Open-Ended Coaxial Sensor on its Reflection Coefficient
This paper presents a calibration technique for a coaxial sensor using a transmission signal approach. The sensor was fabricated from commercially available RG402/U and RG405/U semi-rigid coaxial cable. The length of the coaxial sensor was correlated with the attenuation and standing wave inside the coaxial line. The functions of multiple reflection amplitude and tolerance length with respect to the actual length of coaxial line were empirically formulated using regression analysis. The tolerances and the undesired standing wave which occurs along the coaxial line were analyzed in detai
Full one-loop electroweak radiative corrections to single photon production in e+e-
Large scale calculation for the radiative corrections required for the
current and future collider experiments can be done automatically using the
GRACE-LOOP system. Here several results for e+e- --> 3-body processes are
presented including e+e- --> e+e-H and e+e- --> nu nubar gamma.Comment: 5 pages, contribution to ACAT03(Dec. 2003
Fault diagnostic instrumentation design for environmental control and life support systems
As a development phase moves toward flight hardware, the system availability becomes an important design aspect which requires high reliability and maintainability. As part of continous development efforts, a program to evaluate, design, and demonstrate advanced instrumentation fault diagnostics was successfully completed. Fault tolerance designs for reliability and other instrumenation capabilities to increase maintainability were evaluated and studied
Business Ecosystem and Stakeholdersâ Role Transformation: Evidence from Chinaâs Emerging Electric Vehicle Industry
Nurturing an emerging industryâs business ecosystem always requires stakeholdersâ efforts and role transformation. By systematically reviewing and studying the evolution of the Chinese electric vehicle industry, this paper constructs a three-dimensional theoretical framework including stages of business ecosystem lifecycle, stakeholder classification and functional roles, to analyse the transformation both of different stakeholders and their functional roles. The findings show that business ecosystem stakeholders have experienced role transformation following a mechanism defined as the âTriple Oscillationâ Model during the evolution of the emerging industry. These findings also help develop a conceptual model of agent-based system for business ecosystem evolution, which could be a starting point for further emerging industry study
Scheme for sharing classical information via tripartite entangled states
We investigate schemes for quantum secret sharing and quantum dense coding
via tripartite entangled states. We present a scheme for sharing classical
information via entanglement swapping using two tripartite entangled GHZ
states. In order to throw light upon the security affairs of the quantum dense
coding protocol, we also suggest a secure quantum dense coding scheme via W
state in analogy with the theory of sharing information among involved users.Comment: 4 pages, no figure. A complete rewrritten vession, accepted for
publication in Chinese Physic
Cerenkov Line Emission as a Possible Mechanism of X-ray Lines in Gamma-ray Bursts
The recent discoveries of X-ray lines in the afterglows of gamma-ray bursts
(GRBs) provide significant clues to the nature of GRB progenitors and central
environments. However, the iron line interpretation by fluorescence or
recombination mechanism requires a large amount of iron material. We argue that
the very strong iron line could be attributed to an alternative mechanism:
Cerenkov line emission since relativistic electrons and dense medium exist near
GRB sites. Therefore, the broad iron lines are expected, and line intensity
will be nearly independent of the iron abundance, the medium with the
anomalously high Fe abundance is not required.Comment: 4 pages, revised version accepted for the publication in ApJ
Optimisation of Fine Pitch Contactor and Test Board for QFN Package
Fine pitch contactor describes a contactor with smaller air gap between the contact pins. It is used for testing small portable devices. This work presents the optimised way of designing the 0.4 mm pitch contactor and test board for QFN package. The signal integrity of fine pitch test contactor has become a concern due to the small air-gap between the pins that leads to signal crosstalk and impedance mismatch issues. The same challenge had been seen when designing the fine pitch test board because of the requirement to meet 0.4 mm pitch for typical hand-held devices. It restricts the trace routing with typical design rules at the contactor mounting area due to the limited spaces. This would bring to impedance discontinuity and crosstalk effect. Therefore, optimised design rules on the fine pitch contactor and test board are necessary. Full-wave modelling and system level simulation were demonstrated to study the fine pitch design rules. While the full-wave modelling was to construct the contactor and test board components, the system level simulation was intended to study the signal transmission when propagating from one component to another. Overall, designing the fine pitch contactor requires extra study on the signal integrity and layout design. This paper presents a method to study and design the fine pitch contactor design. It reports the test board to achieve minimum losses and distortion test system for functional testing. Our simulation results for finepitch contactor model show that the return loss is less than 12 dB at 4 GHz
Ground state properties of one-dimensional Bose-Fermi mixtures
Bose-Fermi mixtures in one dimension are studied in detail on the basis of an
exact solution. Corresponding to three possible choices of the referecce state
in the quantum inverse scattering method, three sets of Bethe-ansatz equations
are derived explicitly. The features of the ground state and low-lying
excitations are investigated. The ground state phase diagram caused by the
external field and chemical potential is obtained
- âŠ