A model for concept evaluation in design––an application to mechatronics design of robot grippers

In this paper, an approach for the modelling of the evaluation process in the conceptual design phase is presented. During the design process, the generated candidate solutions are evaluated. The evaluation is achieved by calculating a score that is based on specific criteria that are presented as elements of a vector. Weight factors are applied to highlight the importance of each criterion. The formulation of the evaluation score is based on t-norm and averaging operators with the assumption that the universe of discourse of criteria is [0,1]. A discussion of the meaning of these operators and a comparative study of them is presented. As an application, the mechatronics design of robot grippers for handling fabrics is analysed. The elements of the mechatronics index are presented in terms of flexibility, intelligence and complexity. This index is formulated using the variety of the t-norms and averaging operators to show the weaks and strengths of each of them.     

“The top 10 most competitive enterprises of 2007 in the optical communications field of China”

Organizer：
The Professional Optical Communications Committee of China Institute of Communications
The Professional Communications Lines Committee of China Institute of Communications
“Network Telecom”magazine     

Comments on “A model-based design methodology for the development of mechatronic systems”

In the paper by Barbieri et al. (2014), a design methodology, based on the W life cycle process model, is presented and SysML is proposed as a tool to support the whole development process. In this letter, we discuss the presented approach, we point out technical errors and raise additional issues that might help in making the proposed approach applicable.     

Thermal–mechanical behavior of the bonding wire for a power module subjected to the power cycling test

Two analytical methods were proposed in this research, coupled electro-thermal finite element (FE) analysis and thermal–mechanical FE analysis, to analyze the mechanical behavior of bonding wire of power module under cyclic power loads, and the International Electrotechnical Commission standard is adopted in conducting a power cycling test. The exterior temperature distribution was measured by an infrared thermometer. Moreover, the junction temperature is calculated from the given thermal impedance of the semiconductor chip, chip power loss, and case temperature. Subsequently, the simulated temperature distribution via electro-thermal FE analysis is compared with experimental results to validate the methodology used in the aforementioned analysis. The analysis shows compressive stress at the wire/chip interface due to CTE mismatch between the aluminum and the chip. Moreover, the major driving force contributing to the shear stress at the interface is the self-expansion of the wire bump.     

Alternatives for mobile operators in the competitive 3G and beyond business

The importance of analyzing different business models and technologies in the mobile industry has become more crucial for the investment policy of the telecom operators. This paper aims to cover some of the most interesting business alternatives in providing the new 3G and beyond services including cases where the operator already has an existing second-generation cellular network and perhaps even a license for the 3G UMTS network, and cases where the operator does not have any existing network. Three cases for incumbents and new entrants are foreseen, leaving alternatives for new competing 3G technology deployment or acting as a mobile virtual network operator (MVNO) without owning any radio infrastructure. A techno-economic approach has been used to identify business opportunities and quantify the potential profitability of different kind of business players. The scenarios have been analyzed in the Western European context by different country groups that are not exactly representative of any defined country, but rather share typical demographic characteristics.     

Research and design of the protection circuits in LD controller

1 Introduction Nowadays, semiconductor LD has been widely used in the fields of communication, military, medicine and so on. LDs have become the main stream of semiconductor lasers. LDs have high power density and sky high quantum efficiency. Even weak dr…     

Systematic study of the influence of the Czochralski hot zone design on the point defect distribution with respect to a “perfect” crystal

In the present paper the influence of the hot zone design on the quality and yield of silicon crystals with 100 mm and 300 mm diameters is numerically studied using the software package CrysVUn. Based on the numerical results solutions for the design of the heat shields are identified which allow nominally to grow the crystals at higher growth velocities, and at the same time with improved quality in terms of smaller point defect concentrations and improved radial uniformity, compared to conventional hot zones.     

Optimal design of the T-knot “knot reactance” effect in 3-dB microstrip hybrid ring

We study the T-knot “knot reactance” effect of 3-dB microstrip hybrid ring in experimental and theoretical analysis based on microwave network theory and the parity mode analysis method. Experimental results show that the modified microstrip hybrid ring's overall performance has been improved. So the feasibility of amend method is proved, which lays a foundation to further optimize the design of the hybrid ring.     

On the design of feed-forward ΣΔ interface for MEMS based accelerometers

High order ???? interface is popular for high resolution micro-electro-mechanical systems. Previous researches are mainly about the coefficients of the multiple feedback electromechanical ???? modulators. In the work presented here, a systematic design method for the feed forward ???? interfaces is proposed. Simulations show that utilizing the proposed method, feed forward and the optimized multiple feedback electromechanical sigma-delta modulators have almost the same SQNRs when a compensator pole is added to the feed forward structure. However, the feed forward structures have many advantages, so the proposed method is a promising alternative method for the multiple feedback structure.     

Accurate calculation and Matlab based fast realization of merit function’s Hesse matrix for the design of multilayer optical coating

To improve the current status of home multilayer optical coating design with low speed and poor efficiency when a large layer number occurs, the accurate calculation and fast realization of merit function＇s gradient and Hesse matrix is pointed out. Based on the matrix method to calculate the spectral properties of multilayer optical coating, an analytic model is established theoretically. And the corresponding accurate and fast computation is successfully achieved by programming with Matlab. Theoretical and simulated results indicate that this model is mathematically strict and accurate, and its maximal precision can reach floating-point operations in the computer, with short time and fast speed. Thus it is very suitable to improve the optimal search speed and efficiency of local optimization methods based on the derivatives of merit fimction. It has outstanding performance in multilayer optical coating design with a large layer number.     

Correlation matching method for the weak stationarity test of LRD traffic

The stationarity test of long-range dependent (LRD) traffic remains a challenge problem in the field of traffic engineering. Due to the importance of traffic theory in the Internet, to find a solution to that problem is greatly desired. This paper presents a method of the weak stationarity test of a single history LRD traffic series of finite length. How to apply this method to testing the stationarity of real traffic is demonstrated. The results in this paper suggest that there may be no general conclusion that traffic is either stationary or non-stationary since the stationarity of traffic is observation-scale dependent. Some of the investigated real-traffic traces that are stationary in an observation scale may be non-stationary in a larger observation scale.     

Description of the Mueller Matrix for Multiple Scatteringat 90°

Mueller matrix elements are presented represen ting scatter to 90° from an incident polarized laser beam. The cases considered include five particle sizes (such as l.24 μm, 0.494 μm, 0.36 μm, 0.123 μm, and 0.065 μm), two concentr ations (such as 0.002 5% and 0.005% by volume), and three detector depths (such as 0, l.5 cm, and 3 cm into the scat tering volume). If the magnitudes of the elements can be rounded off to the near est 0.01, a particle size dependence is described by the resulting average mat rices, which is only two matrices for d >0.22 μm and d <0.22 μm which are nonsingular and asymmetric, respectively.     

Method of the estimation of the parameters of a variable length Markov chain based on Fisher’s exact test

A method of the estimation of the parameters of a variable length Markov chain based on the use of Fisher’s exact test is proposed. The method has been applied to the problem of classification of convolutionally coded binary signals. Computer simulation has shown that the constructed models have a considerably smaller number of parameters as compared to the models based on the Kullbak-Leibler criterion, which is very popular in constructing variable-order Markov models.     

A new approach to the design and analysis of peer‐to‐peer mobile networks

This paper introduces a new model and methodological approach for dealing with the probabilistic nature of mobile networks based on the theory of random graphs. Probabilistic dependence between the random links prevents the direct application of the theory of random graphs to communication networks. The new model, termed Random Network Model, generalizes conventional random graph models to allow for the inclusion of link dependencies in a mobile network. The new Random Network Model is obtained through the superposition of Kolmogorov complexity and random graph theory, making in this way random graph theory applicable to mobile networks. To the best of the authors' knowledge, it is the first application of random graphs to the field of mobile networks and a first general modeling framework for dealing with adhoc network mobility. The application of this methodology makes it possible to derive results with proven properties. The theory is demonstrated by addressing the issue of the establishment of a connected virtual backbone among mobile clusterheads in a peertopeer mobile wireless network. Using the Random Network Model, we show that it is possible to construct a randomized distributed algorithm which provides connectivity with high probability, requiring exponentially fewer connections (peertopeer logical links) per clusterhead than the number of connections needed for an algorithm with a worst case deterministic guarantee.     

Very large-scale neighborhood search algorithms for the design of service overlay networks

Service Overlay Networks (SONs) allow virtual operators to create and deploy value-added Internet services with Quality of Service guarantees, while leaving the underlying network infrastructure unchanged. The deployment of a SON can be very expensive, and hence its planning requires careful decisions, including the overlay nodes’ placement and the capacity provisioning of the access links that connect the end-users to the SON infrastructure.     

Modelling the current—voltage characteristic of a fluorescent lamp for computer-aided design

An empirical formula is presented for the voltage-current characteristics of a fluorescent lamp. The three parameters of the formula can easily be obtained from the measured characteristics of the fluorescent lamp without recourse to conventional curve-fitting techniques. By using this formula the analytical study of electronic circuits incorporating fluorescent lamps can be simplified.