Response analysis of an automobile shipping container

The design and development of automobile shipping containers to reduce enroute damage are discussed. Vibration tests were conducted to determine the system structural integrity. A dynamic analysis was made using NASTRAN and the results of the test and the analysis are compared

The Invisible Borders in Internet Transactions: An Empirical Study of eBay\u27s Auction System

The popularity of auctions handled through eBay’s website demonstrates the marketing power of the Internet. This study examines the influences of price, quality, reputation, and country-of-origin effects on buyers’ repeat purchase decisions of jade products listed on eBay. Lower price, although promotes higher volume of bidding, tends to have negative impacts on quality perception. Repeat purchases and reputation differs significantly depending on the country of origin

Walls in supersymmetric massive nonlinear sigma model on complex quadric surface

The Bogomol'nyi-Prasad-Sommerfield (BPS) multiwall solutions are constructed in a massive Kahler nonlinear sigma model on the complex quadric surface, Q^N=SO(N+2)/[SO(N)\times SO(2)] in 3-dimensional space-time. The theory has a non-trivial scalar potential generated by the Scherk-Schwarz dimensional reduction from the massless nonlinear sigma model on Q^N in 4-dimensional space-time and it gives rise to 2[N/2+1] discrete vacua. The BPS wall solutions connecting these vacua are obtained based on the moduli matrix approach. It is also shown that the moduli space of the BPS wall solutions is the complex quadric surface Q^N.Comment: 42 pages, 30 figures, typos corrected, version to appear in PR

Universal Scaling and Signatures of Nodal Structures in Electron Tunneling from Two-Dimensional Semimetals

We present the theory of out-of-plane electron thermal-field emission from 2D semimetals. We show that the current($\mathcal{J}$)-field($F$)-temperature($T$) characteristic is captured by a universal scaling law applicable for broad classes of 2D semimetals, including monolayer and few-layer graphene, nodal point semimetals, nodal line semimetals and Dirac semimetals at the verge of topological phase transition. The low-temperature scaling takes the universal form, $\log\left( \mathcal{J}/F^\gamma \right) \propto -1/F$ with $\gamma = 1$ for 2D semimetals, which is in stark contrast to the classic Fowler-Nordheim scaling of $\gamma = 2$ for 3D metals. Importantly, the Fermi level dependence of the tunneling currents depends sensitively on the nodal structure through the electronic density of states, thus serving as a probe for detecting the various possible nodal structures of 2D semimetals. Our findings provide a theoretical basis for the understanding of tunneling charge transport phenomena in solid/vacuum and solid/solid interfaces, critical for the development of 2D-material-based vacuum and solid-state electronic devices.Comment: 8 pages, 2 figure

N=8 Supergravity 4-point Amplitudes

We present the explicit expressions in N=8 supergravity for the bosonic 4-particle tree and 1-loop amplitudes including vectors and scalars. We also present the candidate 4-point UV divergences in a form of helicity amplitudes, corresponding to 3-loop manifestly N=8 supersymmetric and Lorentz covariant counterterm. This may shed some light on the 3-loop finiteness of N=8 SG and on a conjectured higher loop finiteness. We perform a supersymmetric deformation to complex momentum of the 4-point generating function including higher-loop counterterms and the 1-loop UV finite amplitudes. Using the explicit form of the scalar part of the 3-loop counterterm and of the 1-loop UV finite scalar 4-point amplitudes we find that they both have an unbroken E7 symmetry. We derive from E7 symmetry the low-energy theorem for the 1-loop n-point amplitudes.Comment: 23 p, 4 figure

Recombinant canine single chain insulin analogues: Insulin receptor binding capacity and ability to stimulate glucose uptake

Virtually all diabetic dogs require exogenous insulin therapy to control their hyperglycaemia. In the UK, the only licensed insulin product currently available is a purified porcine insulin preparation. Recombinant insulin is somewhat problematic in terms of its manufacture, since the gene product (preproinsulin) undergoes substantial post-translational modification in pancreatic β cells before it becomes biologically active. The aim of the present study was to develop recombinant canine single chain insulin (SCI) analogues that could be produced in a prokaryotic expression system and which would require minimal processing. Three recombinant SCI constructs were developed in a prokaryotic expression vector, by replacing the insulin C-peptide sequence with one encoding a synthetic peptide (GGGPGKR), or with one of two insulin-like growth factor (IGF)-2 C-peptide coding sequences (human: SRVSRRSR; canine: SRVTRRSSR). Recombinant proteins were expressed in the periplasmic fraction of Escherichia coli and assessed for their ability to bind to the insulin and IGF-1 receptors, and to stimulate glucose uptake in 3T3-L1 adipocytes. All three recombinant SCI analogues demonstrated preferential binding to the insulin receptor compared to the IGF-1 receptor, with increased binding compared to recombinant canine proinsulin. The recombinant SCI analogues stimulated glucose uptake in 3T3-L1 adipocytes compared to negligible uptake using recombinant canine proinsulin, with the canine insulin/cIGF-2 chimaeric SCI analogue demonstrating the greatest effect. Thus, biologically-active recombinant canine SCI analogues can be produced relatively easily in bacteria, which could potentially be used for treatment of diabetic dogs

Applying a Domestic Water-cooled Air-conditioner in Subtropical Cities

Abstract: Water-cooled air-conditioning systems (WACS) are in general more energy efficient than air-cooled airconditioning systems (AACS), especially in subtropical climates where the outdoor air is hot and humid. Related studies focused on evaluating the energy and environmental benefits of WACS over AACS applying to commercial buildings with central air-conditioning. This paper presents an experimental study on the performance of a 3.36 kW prototype water-cooled air conditioner. The prototype is a self-assembled unit. The results show that by the use of water-cooled air-conditioner, the energy performance can be considerably improved. The study provides useful information for the wider use of WACS in residential buildings located in the hot and humid regions

Traffic agents for improving QoS in mixed infrastructure and ad hoc modes wireless LAN

As an important complement to infrastructured wireless networks, mobile ad hoc networks (MANET) are more flexible in providing wireless access services, but more difficult in meeting different quality of service (QoS) requirements for mobile customers. Both infrastructure and ad hoc network structures are supported in wireless local area networks (WLAN), which can offer high data-rate wireless multimedia services to the mobile stations (MSs) in a limited geographical area. For those out-of-coverage MSs, how to effectively connect them to the access point (AP) and provide QoS support is a challenging issue. By mixing the infrastructure and the ad hoc modes in WLAN, we propose in this paper a new coverage improvement scheme that can identify suitable idle MSs in good service zones as traffic agents (TAs) to relay traffic from those out-of-coverage MSs to the AP. The service coverage area of WLAN is then expanded. The QoS requirements (e.g., bandwidth) of those MSs are considered in the selection process of corresponding TAs. Mathematical analysis, verified by computer simulations, shows that the proposed TA scheme can effectively reduce blocking probability when traffic load is light

Reflecting Electron Energy Loss Spectroscopy Study of Fe, Ni and Fe-Ni Compounds

Experimental inelastic scattering cross sections of Fe, Ni and their compound from reflection-electron-energy-Loss spectroscopy (REELS) spectra are presented. Quantitative analysis of REELS spectra were carried out by using Tougaard-Yubero QUEELS-??(k, ??)-REELS software [1]. Theoretical inelastic scattering cross section KSC from simulated energy loss function (ELF) and experimental inelastic scattering cross section from REELS spectra at four primary electron energies of 500eV, 1000eV, 1500eV and 2000eV have been investigated. Theoretical inelastic scattering cross section determined through a dielectric-response of solid-electron interaction using Drude-Lindhard oscillator were compared with experimental inelastic scattering cross section from REELS spectra. The peak position, strength and width of oscillators also were determined quantitatively for these materials. Plasmon and interband transition peak appear in energy loss below 50 eV for Fe, Ni [2] and Fe-Ni compounds. Excitation of 3s and 3p contributed in energy loss above 50 eV for Fe and Fe-Ni compounds, for Ni only excitations of 3p occur in this region. Good quantitative agreement is found between the theoretical predictions and the experimental findings for the inelastic scattering cross section. The theoretically calculated inelastic mean free path (IMFP) is found to depend on both primary energy and the amount of Fe in compounds. The IMFP increases with increasing the primary energies and decreases with reducing the amount of Fe in compounds

Polynomial Growth Harmonic Functions on Finitely Generated Abelian Groups

In the present paper, we develop geometric analytic techniques on Cayley graphs of finitely generated abelian groups to study the polynomial growth harmonic functions. We develop a geometric analytic proof of the classical Heilbronn theorem and the recent Nayar theorem on polynomial growth harmonic functions on lattices \mathds{Z}^n that does not use a representation formula for harmonic functions. We also calculate the precise dimension of the space of polynomial growth harmonic functions on finitely generated abelian groups. While the Cayley graph not only depends on the abelian group, but also on the choice of a generating set, we find that this dimension depends only on the group itself.Comment: 15 pages, to appear in Ann. Global Anal. Geo