磨削直线轴承弧形外圆的新方法

在分析外圆工件贯穿无心磨削原理的基础上 ,提出一种既可保证磨削圆度又可提高磨削效率的直线轴承弧形外圆磨削新方法 ,并设计了辅助夹紧装置。     

连续管现场快速修复技术

连续管作业时会出现压扁、折弯和局部破损等问题,在现场需要安全快速切断连续管损坏部位,并实施管-管对接焊修复工程。为此,研制了便携式和全位置连续管校直机、旋转锥套式胀圆器、管口开坡口机以及6个自由度对中机构等成套修复设备。在采油井口连续管作业现场,运用这些修复设备和试验制定的修复工艺,在很短时间内就可以高质量地修复损坏的连续管。修复后连续管接头的疲劳循环次数达到母材管的61%。应用连续管快速修复技术可大大提高连续管井下作业效率,保证作业的安全性。     

Screening efficiency of the Hardy–Rand–Rittler (HRR) colour test (4th edn)

This study evaluates the screening efficiency of the Hardy–Rand–Rittler (HRR) 4th edition colour test. This test was also compared with results from the Ishihara test. Thirty-nine subjects with congenital red–green deficiency and 120 colour normal subjects participated in the study. The subjects were shown the Ishihara (concise version, 2001) and the HRR (4th edn) pseudoisochromatic plates. Each plate was viewed for 3?s. A Macbeth Easel lamp was used for illumination (70?foot-candle). The HRR test had 100% sensitivity and the specificity was 63%. The overall efficiency of the HRR test was less than that of the Ishihara. The results also indicated that plate seven of HRR (4th edn) has poor screening efficiency. Thus the HRR is good for identifying colour deficient subjects but a caveat is that it fails too many normals.     

Distributed NGD active circuit for RF-microwave communication

This paper is aimed to the investigation on innovative distributed negative group delay (DNGD) circuits for RF communication. Thanks to the analogy between the lumped and distributed circuits, NGD circuit topologies were identified. By using the S-parameter theory, analysis and synthesis methods of these topologies are proposed. The DNGD circuits developed are mainly comprised of a transistor combined with a series resistance ended by a stub. Then, synthesis relations enabling to determine the NGD circuit parameters from the desired NGD and gain values are established. As application, an active phase shifter (PS) operating independently with the frequency based on the cascade of PGD and NGD devices was synthesized. First, an NGD PS with transmission phase of (135 ± 5)° around 2.56 GHz over the bandwidth of about 1.02 GHz was obtained. Then, a two-stage DNGD PS exhibiting 90° with ±10° flatness from 4.1 GHz to 6.8 GHz was designed. The DNGD circuit presented can be used in various telecommunication areas notably for correcting RF/numerical signal delays in the RF-microwave analogue-digital devices.     

尾矿库排水系统护栏装置的设计与运用

为了保证排水系统的正常运行,避免漂浮物通过溢水井进入排水管(或隧洞)而发生堵塞,提出在溢水井外围设置护栏的方法。对于护栏防护装置,以实例给出具体材料的规格和尺寸大小,以及装置的基本原理和装置对排洪量的影响。论证排水系统设置护栏的必要性,并从护栏装置的角度提出溢水井设计的基本要求。     

Radiation tolerant nano-FED biosensing for space application

A p-type polysilicon nanowire and silicon nano-channel combination based biosensor was developed, which has the potential to detect pathogens and thus protect crew safety aboard long-term manned flight programmes in high radiation space flights. This study outlines structures, which compose the biosensor, and demonstrates that the nano-device utilised herein is total dose radiation hardened. Highly doped polysilicon nanowires (30–100?nm) in nano-field-effect device (FED) were fabricated on silicon/silicon dioxide wafers and insulated with a thin polyimide layer. When the targeted gene, Escherichia coli DH5 alpha 16S rRNA, incubated on the device surface, the constant overall impedance increased or decreased depending on the electronic charge, mass and composition of the target molecule. All measurements were carried under 25 MeV S-Band linear accelerator followed by impedance measurements. Current sets of experiments show these nano-FED can form the basis of a robust, very sensitive handheld tool for pathogen detection in space application.     

新型紧急切断阀综合校验装置的研制

针对目前紧急切断阀校验装置集成程度低、检验精度差的现状,研发了一种紧急切断阀综合校验装置。该装置采用气液双相介质组成的循环系统,能够实现压力信号、流量信号的自动采集,可以直接读取数据和曲线图表,依次完成紧急切断阀的密封性能、耐压性能、切断时间性能、过流切断性能的校验。     

可调高组合推拉式转载机尾全封闭装置

放顶煤回采工作中,转载机尾的工作环境是事故的多发区。本装置通过液压油缸实现升降,通过柔性吊帘进行封闭,不仅实现了大块煤的顺利通过,而且可完全配合端头支架的正常工作。此封闭装置可以极大改善转载机尾的工作环境,减少事故的发生。     

试析快速切换装置在多电源供电系统中的应用

首先对快切装置的工作原理进行概述，从快速同期切换、同期捕捉切换、残压切换以及长延时切换四个方面入手，对快切装置基本类型进行解析，并以此为依据，提出快速切换装置在多电源供电系统中的应用对策，探究目的在于实现提升多电源供电系统运行效率的同时，助力企业长远发展。     

Practical access control management for distributed collaborative editors

The project summarized in this article aims at developing techniques to support access control in Real-Time Distributed Collaborative Editors (RCE). The ever-increasing role of RCE in academic, industry and society comforts the expansion of data sharing and raises growing concerns about controlling access to this data. Indeed, RCE allow for a human–computer–human interaction in a decentralized fashion. Thus, access control for RCE requires a careful design since they need dynamic access changes and low latency access to shared document while maintaining its consistency.In this article, we propose a flexible access control model where the shared document and its authorization policy are replicated in the local memory of each user. To deal with latency and dynamic access changes, we use an optimistic access control technique in such a way that enforcement of authorizations is retroactive. Our model is generic enough to be deployed on the top of the most of existing logging-based collaborative systems. Indeed, it does not entail overheads and it does not affect the convergence of the shared document. We show that naive coordination between updates of both copies can create security holes on the shared document, by permitting illegal modifications or rejecting legal modifications and present our solutions to avoid these problems. Finally, we present a prototype for managing authorizations in collaborative editing work in a decentralized fashion. Thus our model may be deployed easily on mobile devices over P2P networks.