面内弯矩作用下弯管应力高次解

该文采用应变分析和能量法得出了面内弯矩作用下弯管环向和轴向应力的解析解,并提出了高次解的求解方法。该方法的计算结果与其他各种解析解的结果进行比较表明:该文提出的方法能得到更精确的结果,并适用于所有弯曲系数的弯管。该方法可用于计算弯管在面内闭合弯矩和面内张开弯矩下的应力。     

The combined weight function method application for a hole emanated crack

An approximate weight function construction for a hole emanated crack as a sum of an asymptotic term and a correction one is considered. Based on the known approximate fundamental solution for a half-plane with an edge crack the new weight function asymptotic term which satisfies both known solutions for an edge crack in a half-plane and for an inner crack in an infinite plane is proposed. The practical usefulness of the method is demonstrated for a hole emanated crack in an infinite plate and for a thick cylinder with an edge crack at the inner surface.     

Wigner distribution function of an Airy beam

We study the Wigner distribution function (WDF) of an Airy beam. The analytical expression of the WDF of an Airy beam is obtained. Numerical and graphical results of the WDF of an Airy beam provide an intuitive picture to explain the intriguing features of an Airy beam, such as weak diffraction, curved propagation, and self-healing. Our results confirm that these novel properties of an Airy beam are attributed to the continuum of sideways contributions to the field.     

On how access to an insurance market affects investments in safety measures, based on the expected utility theory

This paper focuses on how access to an insurance market should influence investments in safety measures in accordance with the ruling paradigm for decision-making under uncertainty—the expected utility theory. We show that access to an insurance market in most situations will influence investments in safety measures. For an expected utility maximizer, an overinvestment in safety measures is likely if access to an insurance market is ignored, while an underinvestment in safety measures is likely if insurance is purchased without paying attention to the possibility for reducing the probability and/or consequences of an accidental event by safety measures.     

On the optimization of free resources using non-homogeneous Markov chain software rejuvenation model

Software rejuvenation is an important way to counteract the phenomenon of software aging and system failures. It is a preventive and proactive technique, which consists of periodically restarting an application at a clean internal state. Starting an application generally means that an amount of memory is captured and closing an application engenders the release of an amount of memory. In general, when an application is initiated an amount of memory is captured and when terminated an amount of memory is released. In this paper a model describing the amount of free memory on a system is presented. The modelling is formulated under a continuous time Markov chain framework. Additionally the cost of performing rejuvenation is also taken into consideration, a cost function for the model is produced and a rejuvenation policy is proposed. The contribution of this paper consists of using a cyclic non-homogeneous Markov chain in order to study the overall behaviour of the system capturing time dependence of the rejuvenation rates and deriving an optimal rejuvenation policy. Finally, a case study is presented in order to illustrate the results of the cost analysis.     

Adopting an Open Innovation Program with Supply Chain Management in China: A Case Study

This study examines how an open innovation program can be implemented in practice by a foreign company operating in China with due consideration of traditional supply chain management practices. A case study of an open innovation initiative in a renowned global electrical appliance company in China is explored. The study has found that supply chain managers can play an important role in innovation sourcing, provided an open innovation perspective is adopted. In addition, an open innovation framework complemented by an open innovation funnel is presented. The framework provides new practical insights for engineering managers seeking to implement open innovation programs. The study bridges the gap between academic studies and industrial practice regarding the roles of different functional units in an environment of open innovation.     

Optical integrator for optical dark-soliton detection and pulse shaping

The design and analysis of an Nth-order optical integrator using the digital filter technique is presented. The optical integrator is synthesized using planar-waveguide technology. It is shown that a first-order optical integrator can be used as an optical dark-soliton detector by converting an optical dark-soliton pulse into an optical bell-shaped pulse for ease of detection. The optical integrators can generate an optical step function, staircase function, and paraboliclike functions from input optical Gaussian pulses. The optical integrators may be potentially used as basic building blocks of all-optical signal processing systems because the time integrals of signals may sometimes be required for further use or analysis. Furthermore, an optical integrator may be used for the shaping of optical pulses or in an optical feedback control system.     

波分复用光纤象束系统成象质量研究

用成象系统象的光学信息量分析了波长复用对象束系统传象质量的影响。波长复用增加了象束中每根光纤传输的象元数,从而改善了象束的成象分辨率和信噪比。     

Three-dimensional display of a horizontal-parallax-only hologram

We propose a three-dimensional (3D) holographic display by converting an optically recorded complex full-parallax (FP) hologram to an off-axis horizontal-parallax-only (HPO) hologram. First, we record the complex FP hologram of an object using optical scanning holography. We then convert the complex FP hologram to an off-axis HPO hologram through fringe-matched Gaussian low-pass filtering and with the introduction of an off-axis reference. Finally, we reconstruct the off-axis HPO hologram optically using an amplitude-only spatial light modulator. Until now, only computer-generated HPO holograms have been displayed optically. To the best of our knowledge, this is the first demonstration of a 3D display of an optically recorded HPO hologram.     

Multichannel raman scattering: Comparison of an intensified linear diode array and an ICCD detector

A comparison of the Signal to Noise (S/N) ratio was made between an Intensified Linear Diode Array detector (ILDA) and an Intensified Charge Coupled Device (ICCD) applied to single shot pulsed spontaneous Raman spectroscopy with an excimer laser. As a result in this special application the S/N ratio of an ILDA is two times better than that of an ICCD.     

Augmenting a Factorial Experiment When One Factor Is an Uncontrollable Random Variable: A Case Study

Process engineers at an automobile assembly plant wanted to develop a model for on-line process control in an assembly line. During an experiment to estimate the model, an uncontrollable variable was discovered to have a significant effect, but its values in the experiment were not representative of values in actual production. Through this case study, we present design criteria and assess sampling strategies for augmenting a factorial experiment to incorporate an additional factor that was found to be an uncontrollable independent normally distributed random variable. Our results demonstrate the potential improvement in on-line process control when experiments are augmented using these design criteria.     

A theoretical resistance-curve based on nonproportional plastic strain

Using an exact solution for an elliptical hole in a perfectly plastic material, an expression is derived for the resistance of a ductile material undergoing subcritical crack propagation in the plane. This resistance curve is based on an analogy to the J-integral where an energy dissipation rate is determined rather than an energy release rate. The Tresca yield condition under plane stress loading conditions is employed in this derivation as well as finite deformation theory. This resistance curve is applicable to the initial stage of subcritical crack growth for a ductile material subject to crack tip blunting.     

Deriving the dynamic stress function using complex function and its application to the analysis of the stress distribution around an elliptical hole

In the engineering field, analyzing the stress distribution of an elastic body to which an impact force is applied at its boundary is one of the most interesting problems. However, owing to the absence of a useful and easy method of analyzing the stress distribution of an arbitrarily shaped body, it is difficult to grasp the strength of an elastic body. Therefore, we first devise an easy and useful method employing the complex stress function and then analyze the stress distribution of a body that has an elliptical hole.     

Comparison of iterative and monte carlo methods for calculation of the Aureole about a point source in the earth's atmosphere

Point sources in the atmosphere are surrounded by aureoles because of atmospheric scattering. The properties of an aureole were calculated by use of a Monte Carlo approach and an iterative method for an isotropic source and an axially symmetric emission source inside an infinite homogeneous atmosphere. The influence of single-scattering albedo, optical depth between source and observer, and source intensity anisotropy were studied from both approaches. For each situation, the limits and advantages of the Monte Carlo technique and the iterative method are described.     

Internally excited acoustic resonator for photoacoustic trace detection

The quantum-cascade laser can be used as an infrared source for a small portable photoacoustic trace gas detector. The device that we describe uses a quantum-cascade laser without collimating optics mounted inside an acoustic resonator. The laser is positioned in the center of a longitudinal resonator at a pressure antinode and emits radiation along the length of the resonator exciting an axially symmetric longitudinal acoustic mode of an open-ended cylindrical resonator. Experiments are reported with an 8-microm, quasi-cw-modulated, room-temperature laser used to detect N2O.     

Phase retrieval on annular and annular sector pupils by using the eigenfunction method to solve the transport of intensity equation

Phase retrieval on an annular pupil and an annular sector pupil by using the eigenfunction method to solve the transport of intensity equation is proposed. The analytic expressions of Laplacian eigenfunctions with the Neumann boundary condition on an annular pupil and an annular sector pupil are given. The phase can be expanded as a set of eigenfunctions on the corresponding pupil, and the coefficients of the eigenfunctions can be obtained by the integral of the eigenfunction and the intensity derivative along the optical axis. Phase retrieval by the eigenfunction method on an annular pupil and an annular sector pupil is simulated, and accurate retrieved results are obtained.     

Determining optimum operating characteristics for a continuous processing machine centre

The purpose of this paper is to illustrate an approach to determining a minimum cost operating regimen for n continuous processing machine centre. A variational analysis is employed to determine an optimal processing trajectory, and from this an approach to establishing an upperbound on the theoretical number of machines employed in processing can be established     

Choosing the Optimum Lot Size for a Reordering Policy with Instantaneous Emergency Deliveries

A reordering policy, to maintain the level of stock in an inventory, is given which allows for two types of orders: regular orders which are filled in strict rotation with the time to fill an order exponentially distributed, or an emergency order which, it is supposed, is filled instantaneously (or effectively so). The optimum lot size of an order is that which minimizes the average operating cost per unit time over an infinite time span. The solution is given for the case in which the items in storage are subject to Poisson demand and the costs of maintaining the stock level are linear functions of the lot size of an order.     

基于过程仿真的企业模型层次分析法

把层次分析方法引入到企业模型的分析评价中，结合过程仿真技术，提出了基于过程仿真的企业模型层次分析法。介绍了面向对象的过程仿真机制，并详细地描述了经过一定扩展后的层次分析法。阐述了基于过程仿真的企业模型层次分析法在实际企业中的应用。     

Off-axis refractive mass-transported gallium-phosphide microlens array for the reduction of distortion in an optical interconnect system

Mass-transport smoothing has been used to fabricate an array of off-axis gallium-phosphide microlenses for use in an optical interconnection system employing a single macroscopic lens to image an array of vertical-cavity surface-emitting lasers (VCSEL's) onto a detector array. Steering the individual VCSEL beams through the center of the relay lens creates an optical system with low distortion.