引线框架多工位级进模设计

通过对RT72 2 2A2 (1)引线框架模具的设计 ,介绍了在吸收引进模具的基础上 ,自主研制开发国产化模具 ,并着重解决原模具结构及产品设计的不足之处。

Idiopathic fistula-in-ano

Fistula-in-ano is the most common form of perineal sepsis.Typically,a fistula includes an internal opening,a track,and an external opening.The external opening might acutely appear following infection and/or an abscess,or more insiduously in a chronic manner.Management includes control of infection,assessment of the fistulous track in relation to the anal sphincter muscle,and finally,definitive treatment of the fistula.Fistulotomy was the most commonly used mode of management,but concerns about post-fistulotomy incontinence prompted the use of sphincter preserving techniques such as advancement flaps,fibrin glue,collagen fistula plug,ligation of the intersphincteric fistula track,and stem cells.Many descriptive and comparative studies have evaluated these different techniques with variable outcomes.The lack of consistent results,level I evidence,or long-term follow-up,as well as the heterogeneity of fistula pathology has prevented a definitive treatment algorithm.This article will review the most commonly available modalities and techniques for managing idiopathic fistula-in-ano.

Development of a continuum robot for colonoscopy

A novel continuum robot for colonoscopy is presented.The aim is to develop a robot for colonoscopywhich can provide the same functions as conventional colonoscope,but much less pain and discomfort forpatient.In contrast to traditional rigid-link robot,the robot features a continuous backbone with nojoints.The continuum robot is 300 mm in total length and 12 mm in diameter that is less than the averagediameter of human colon(20 mm).The robot has a total of 4 DOF(degrees of freedom)and is actuatedremotely by 6 hybrid step motors through super-elastic NiTi wires.Its shape can be changed with highdexterity,therefore ensuring its adaptability to the tortuous shape of human colon.The mechanical struc-ture,kinematics and DSP-based control system are discussed; prototype experiments are carried out tovalidate the kinematics model and to show the motion performances.

Impact of Regional Development on Carbon Emission: Empirical Evidence Across Countries

Global warming is recently an urgent issue worldwide. The increase of carbon emissions induced by human economic activi- ties has become a major driving force behind global climate change. Thus, as a matter of social responsibility, reasonable carbon con- straints should be implemented to ensure environmental security and sustainable development for every country. Based on a summary of studies that examined the relationship between carbon emissions and regional development, this paper shows that human activity-led carbon emission is caused by the combination of several influencing factors, including population size, income level, and technical pro- gress. Thus, a quantitative model derived from IPAT-ImPACT-Kaya series and STIRPAT models was established. Empirical analysis using multivariate nonlinear regression demonstrated that the origins of growing global carbon emission included the increasing influ- encing elasticity of the population size and the declining negative effect of technical progress. Meanwhile, in context of classification of country groups at different income levels, according to the comparison of fluctuating patterns of the influencing elasticity, technical progress was found as the main factor influencing carbon emission levels in high-income countries, and population size might he the controlling factor in middle-income countries. However, for low-income countries, the nonlinear relationship between carbon emission and its influencing factors was not significant, whereas population growth was identified as an important potential driving force in future carbon emissions. This study can therefore provide a reference for the formulation of policies on carbon constraints, especially to de- velop more efficient carbon mitigating policies for countries at different income levels.

A COMBINED ADMISSION CONTROL ALGORITHM WITH DA PROTOCOL FOR SATELLITE ATM NETWORKS

Admission control is an important strategy for Quality of Service (QoS) provisioning in Asynchro- nous Transfer Mode (ATM) networks. Based on a control-theory model of resources on-Demand Allocation (DA) protocol, the paper studies the effect of the protocol on the statistical characteristics of network traffic, and proposes a combined connection admission control algorithm with the DA protocol to achieve full utiliza- tion of link resources in satellite communication systems. The proposed algorithm is based on the cross-layer-design approach. Theoretical analysis and system simulation results show that the proposed algo- rithm can admit more connections within certain admission thresholds than one that does not take into account the DA protocol. Thus, the proposed algorithm can increase admission ratio of traffic sources for satellite ATM networks and improve satellite link utilization.

The practice of mine ventilation engineering

The practice of ventilation is continually evolving with new technological advances developed in the mining industry.In recent years the advances in diesel engine technologies,ventilation modeling software,and ventilation management capacities have redefined the historical methods used to evaluate systems.The advances re-evaluate previous methods used to calculate the airflow requirements for the dilution of diesel exhaust fumes.Modeling software has become an integral part of planning and developing ventilation systems in partnership with graphical mine design software packages to generate realistic representations of the mine.Significant advances in ventilation control strategies through remote sensors and monitoring capabilities have been developed to results in cost savings.Though there has been much advancement in mine ventilation technology,the practices and basic ventilation principals enacted through the ventilation engineer cannot be placated with technological advances only.

Significance of modem scientific and technological progress for the development of philosophical anthropology

The methodology of science and technology is a theory concerning general scientific and technical research methods, and its essence belongs to the category of understanding and thinking. Through the study of science and technology methodologies and approaches on the general process of scientific research and technology research, one can grasp the mainstream of modern scientific thinking pattern and means, helping to solve the general regular problems of scientific and technological research. Starting from modern science and technology point of view, this article elaborated the impact of modern scientific progress had on the development of philosophical anthropology from different angles.

Biased Diffusive Search Triggered by ATP Binding During Kinesin's Stepping

In this paper, we present an asymmetry conformational potential with a reflecting boundary and an absorbing boundary, in which the diffusive search of the free head of kinesin motor can be biased toward its forward binding site. Under a wide range of condition, using first-passage time analysis we perform numerical simulation to the Langevin equation, and obtain the dependence of the dwell time for forward steps on the load force. And we calculate the expression for the dwell time by the Laplace transform method. Both numerical and analytical results show that the dwell times exponentially depend on the load force, which provide a simple physical explanation for experimental data. Our results suggest that ATP binding-conformation change in the neck linker plays an important role in unidirectional steps during kinesin＇s mechanochemical cycle.

UAQ4 Magnetic Levitating Train： Propulsion System for Urban Transportation

This paper discusses the design of the propulsion system of the UAQ4 （University of L＇Aquila, model 4） magnetic levitating train which is used for transportation applications in urban environments. UAQ4 is the only magnetic levitating vehicle with resistance motion, except for aerodynamic drag and with energy consumption near zero at low speed. The feasibility of the system has been successfully verified and tested in the laboratory. Propulsion and braking are provided by a novel direct-current linear stepper motor, with the primary formed by permanent magnets distributed on central beam of the track, and the secondary by coils on board the vehicle, instead of the present alternate current linear motors that have well-known disadvantages. The motor working principles are described, and its performances are analyzed, by a finite element numerical model which allows modifying the most important parameters of the system. The main components of a full scale motor for urban transportation are measured and discussed.

Analvsis of the Low-Carbon Tourism Route

With the economic development and social progress, the attention of the people of the ecological civilization has been improved. People＇s consumption patterns have been gradually improved, and the recent low-carbon technologies and low-carbon consumption go constantly into people＇s lives. The development of tourism is the manifestation of the pursuit of ecological civilization. It is a natural use of low-carbon technologies, and is the way the economy of low-carbon consumption. And the low-carbon tourism in further also becomes a necessity.

Parameter Estimations of the TFR Model Under Exponential Distribution at a Normal Stress

The TFR（Tampered Failure Rate） model was proposed by Bhattacharyya and Soejoeti（1989） for step-stress accelerated life tests, On step-stress completely accelerated test occasions, the paper gives a method of estimating parameters under a normal stress.

Research on Intelligent Positioning Bed of Body Gamma Knife Based on Sensor

This paper introduces a design to improve the radiotherapy accuracy of gamma knife. In this design, sensor is used to collect respiratory parameters and tumor displacement (caused by human respiration) model is established through optimization modeling. At the same time, data are transferred to single chip microcomputer (SCM) system by pressure sensor and then stepping motor is controlled by SCM. Finally, the intelligent positioning bed is under the control of stepping motor. As a result, the intelligent positioning bed can move reverse to respiratory law. The experimental results showed that this method can reduce the influence of respiration on tumor displacement, improving the accuracy of intelligent positioning bed with simple circuit and low cost at the same time.

Modeling, measurement and simulation of the disturbance torque generated via solar array drive assembly

The disturbance torque generated via solar array drive assembly(SADA) can significantly degrade the key performance of satellite.The discussed SADA is composed of a two-phase hybrid stepping motor and a set of two-stage straight gear reducer. Firstly, the vibration equation of the two-phase hybrid stepping motor is established via simplifying and linearizing the electromagnetic torque.Secondly, based on the vibration equation established, the disturbance torque model of SADA is created via force analysis and force system simplification. Thirdly, for precisely ground measuring the disturbance torque aroused by SADA, a measurement system,including a strain micro-vibrations measurement platform(SMMP) and a set of gravity unloading device(GUD), is designed.Fourthly, the proposed disturbance torque model is validated by measuring and simulating the disturbance torque produced via SADA driving rigid load through GUD. The results indicate that, the proposed disturbance torque model holds the ability to describe the disturbance torque caused by SADA with high precision. Finally, the disturbance torque emitted by SADA driving a flexible load, designed to simulate solar array, is modeled and simulated via using fixed-interface mode synthesis method(FIMSM). All the conclusions drawn from this article do have a meaningful help for studying the disturbance torque produced by SADA driving solar array on orbit.