基于静态膨胀预裂爆破技术在公路施工中的应用分析

随着我国城市化的不断发展，人们的生活水平进一步提高，有车族的人数也越来越多，公路数量也越来越多，对公路施工质量和效率的求也越来越高。在公路施工过程之中岩石开挖是一个不可避免的过程。为了提高此过程的工作效率和质量，静态膨胀预裂爆破技术得到进一步的使用。该技术的施工质量较高，成本较低，对环境的损坏较小。本文主从该技术的相关释义和其在公路施工中的实际使用等方面对其进行简单的阐述。     

PEX管道施工技术要点

PEX管作为新型给水管材,有着全新的施工工艺,本文着重从PEX管施工前的准备、管道安装等方面介绍了该管的施工技术。如:管道铜卡箍连接、敷设、线脚胀处理、水试压等。     

高边坡石方爆破施工技术要点分析

高边坡石方爆破施工技术在建设工程领域应用日趋广泛,通过对其技术要求、技术要点进行分析与总结,研究保障高边坡石方爆破施工稳定性的措施,在确保施工安全、提高生产效率及促进社会经济的可持续发展有重要意义。     

桩基挖孔劈裂施工技术探究

挖孔桩在公路桥梁施工中经常使用,常规的挖孔方式有爆破和风镐两种方式。这两种方式在一定的条件下,效率和安全性都不高,部分施工条件下禁止使用。为此必须采用新的施工工艺,采用劈裂施工技术可以很好的解决以上的问题,本文就人工挖孔桩的施工技术进行详细阐述。     

拆除爆破模拟技术的开发

在建筑物拆除爆破施工领域中，为了提高其安全性、可靠性、开发运用爆破模拟技术是非常重要的工作，本文从各个方面论述了模拟技术的应用情况。     

筒仓结构无粘结预应力施工技术

本文结合工程实例,从技术特点、施工工艺及操作要点、施工质量及安全要求等方面分析了筒仓结构无粘结预应力施工技术,并对其技术经济效益做了分析。     

板式无碴轨道施工流程及工艺要点

本文结合某客运专线无碴轨道试验段的施工,从下部基础评估、施工测量、底座及凸形挡台施工、轨道板铺设及精确调整、CA砂浆研制及灌注施工、凸形挡台周围树脂灌注、充填式垫板施工等方面,介绍了板式无碴轨道施工技术。该施工技术科学合理、经济、实用,对单元板式无碴轨道的施工具有较好的指导作用。     

深埋隧道Ⅲ级围岩全断面光面爆破施工技术研究

甘孜九龙公路改建项目隧道Ⅲ级围岩采用全断面光面爆破施工技术,该文以此为背景简要介绍了光面爆破的技术原理及施工流程,并采用理论结合经验的方式计算光面爆破的炮孔参数,分析了影响钻孔精度的因素合理提出提高精度的措施,应用于工程施工中后,光面爆破效果良好,各指标均满足规范要求,减少超欠挖量,节省施工成本,缩短了施工工期。     

京沪高速铁路无砟轨道夏季、雨季施工技术保证措施

京沪高速铁路无砟轨道施工中采用无砟轨道夏季、雨季施工技术,达到了预期的质量目标和进度目标。本文对其施工技术加以总结,旨在推广。     

安全爆破回顾

通过对过去爆破工作的回顾，介绍了巷道式爆破、二次爆破、拔根煤破、阶梯爆破、采煤爆破、建筑物拆除爆破、采矿爆破的基本施工技术和安全技术。     

抽检“四分离”工作流程的实践和探索

抽检分离是在产品质量监督检查制度进行改革的过程中出现的一种新的工作模式。福建省纤维检验所对这一工作模式进行了有益的探索,提出和实践了抽检"四分离"工作流程,从理论和实践上为推进了抽检分离积累了经验,取得了良好的经济效益和社会效益。本文分析了抽检"四分离"工作流程的实施过程,并提出了思考。     

"Residence times difference" fluxgate magnetometers

We present analytical and experimental results on fluxgate magnetometers that make use of a readout technique based on residence times. This approach allows for enhancing sensitivity to weak target signals in particular when the reduction of the sensor dimensions are considered. Our approach, exploiting the inherent nonlinear character of the bistable core dynamics, is based on the time domain characterization of the transitions between the two saturation states of the hysteresis loop that is inherent in the ferromagnetic core dynamics. This readout technique can be implemented with bias signals having lower amplitude and frequency than those used in conventional fluxgate processing schemes, thus reducing the device power requirements. The efficacy of this strategy is shown through an analytical approach and via experimental results which suggests guidelines for optimal device design and realization. The experiments have been carried out on a miniaturized laboratory fluxgate prototype; this device shows numerous desirable characteristics, including very good sensitivity and resolution, as well as ease of operation and a very low cost.     

Implementation of diffraction-enhanced imaging experiments: at the NSLS and APS

Diffraction-enhanced imaging is a recently developed X-ray imaging technique that has demonstrated enhanced contrast for dense, highly absorbing materials of interest in materials science and medicine. The implementation of this technique in experiments at the National Synchrotron Light Source and at the Advanced Photon Source is described in detail.     

Integration of multianalyte sensing functions on a capillary-assembled microchip: simultaneous determination of ion concentrations and enzymatic activities by a "drop-and-sip" technique

A general and simple implementation of simultaneous multiparametric sensing in a single microchip is presented by using a capillary-assembled microchip (CAs-CHIP) integrated with the plural different reagent-release capillaries (RRCs), acting as various biochemical sensors. A novel "drop-and-sip" technique of fluid handling is performed with a microliter droplet of a model sample solution containing proteases (trypsin, chymotrypsin, thrombin, elastase) and divalent cations (Ca2+, Zn2+, Mg2+) that passes through the microchannel with the aid of a micropipette as a vacuum pump, concurrently filling each RRC via capillary force. To avert the evaporation of the nanoliter sample volume in each capillary, PDMS oil is dropped on the outlet hole of the CAs-CHIP exploiting the capillary force that results in spontaneous sealing of all the RRCs. In addition, this high-speed sample introduction alleviates the possibility of protein adsorption and capillary cross-contamination, allowing a reliable and multianalyte determination of a sample containing many different proteases and divalent cations by using the fluorescence image analysis. Presented results suggested the possible application of this microchip in the field of drug discovery and systems biology.     

Two-fold efficiency increase by selective excitation of ions for consecutive activation by ion-electron reactions and vibrational excitation in tandem fourier transform ion cyclotron resonance mass spectrometry

A new technique called selective excitation of ions for consecutive activation (SEICA) is proposed for obtaining complementary fragmentation mass spectra from the same precursor ion population. SEICA utilizes precursor ions remaining intact after electron capture dissociation or another ion-electron reaction for efficient MS/MS based on a vibrational excitation (VE) technique, such as infrared multiphoton dissociation. SEICA uses the ability of ion-trapping instruments to detect product ions while retaining inside the trap intact precursor ions, making the latter available for consecutive activation by a VE technique. The possibility of practical implementation of SEICA by software-only modification of a commercial instrument is demonstrated. A 2-fold increase in the efficiency is achieved for both "single-scan" and "multiple-scan" experiments. This improvement can be particularly important for high-sensitivity applications in, for example, proteomics, where limited ECD efficiency poses an obstacle for broad implementation of this technique.     

Mesh-particle interpolations on graphics processing units and multicore central processing units

Particle-mesh interpolations are fundamental operations for particle-in-cell codes, as implemented in vortex methods, plasma dynamics and electrostatics simulations. In these simulations, the mesh is used to solve the field equations and the gradients of the fields are used in order to advance the particles. The time integration of particle trajectories is performed through an extensive resampling of the flow field at the particle locations. The computational performance of this resampling turns out to be limited by the memory bandwidth of the underlying computer architecture. We investigate how mesh-particle interpolation can be efficiently performed on graphics processing units (GPUs) and multicore central processing units (CPUs), and we present two implementation techniques. The single-precision results for the multicore CPU implementation show an acceleration of 45-70×, depending on system size, and an acceleration of 85-155× for the GPU implementation over an efficient single-threaded C++ implementation. In double precision, we observe a performance improvement of 30-40× for the multicore CPU implementation and 20-45× for the GPU implementation. With respect to the 16-threaded standard C++ implementation, the present CPU technique leads to a performance increase of roughly 2.8-3.7× in single precision and 1.7-2.4× in double precision, whereas the GPU technique leads to an improvement of 9× in single precision and 2.2-2.8× in double precision.     

Design and implementation of FPGA-based phase modulation control for series resonant inverters

Owing to the tremendous advances in the digital technology, and improved reliability and performance of the digital control mechanisms, this paper focuses on design and implementation of digital controller using FPGA-based circuit design approach. The digital controller proposed is designed for series resonant inverter used in DC-DC converter applications. Phase modulation technique is proposed for the realization of digital controller on FPGA. The Series Resonant Converter (SRC) is considered in this paper as a preferred converter topology for high power, high voltage power supplies. This paper studies the implementation of phase shift modulation technique using FPGA. The inverter designed, is IGBT based, and Zero Voltage Switching (ZVS) technique is implemented due to reduced stresses on devices and increased efficiency. The phase modulated series resonant inverters (PM-SRC) promotes ZVS operation when its switching frequency is greater than resonant frequency. The designed PM controller is realized using FPGA on which control algorithm and other features of a controller are developed. The series resonant inverter is built and tested for full load under open loop and closed loop conditions at a switching frequency of 20 kHz. The results are presented under varying load conditions. The simulation and the experimental results were found to match closely.     

Risk analysis in plant commissioning: the Multilevel Hazop

The paper deals with risk analysis and management in the realisation of process plants by engineering and contracting companies. Specifically, a new analytical methodology is developed to manage the typical risks of plant commissioning. Following a detailed study of the commissioning process and its criticalities, Hazop is selected as the most suitable approach in forecasting particular risks of this project stage. Starting from the limitations of both Hazop and Human Hazop (the extension of the technique to the field of procedures performed by humans), a new technique (Multilevel Hazop) is suggested which identifies in advance all the criticalities of each commissioning activity and defines actions to reduce risk and optimise dedicated resources. After implementation of Multilevel Hazop in a real commissioning process, a new version of the technique (Two Stage Multilevel Hazop) is proposed. This allows a significant reduction in implementation costs, justifying use of the technique both in innovative or critical cases, where the expected saving from risk reduction is high, and in general contexts.     

坚持“依法治国”与“以德治国”相结合,进一步巩固党的领导

通过对“以德治国”提出的重要意义 ,“以德治国”是“依法治国”的重要补充 ,以及“德治”和“法治”的关系等几方面进行的讨论 ,提出为进一步巩固党的领导 ,实施“以德治国”中官德修养的主要途径和工作方法     

Enhanced-sensitivity version of the Baryscan technique

A promising alternative to the widespread Z-scan technique has been recently proposed. This technique, named Baryscan, is based upon the use of a Position Sensitive Detector (PSD) and is about 170 times more sensitive than the Z-scan technique while preserving its simple theoretical scheme and ease of implementation. In this paper, we demonstrate both numerically and experimentally that inserting a phase plate before the PSD and setting an opaque disk as close as possible to its active area results in a substantial sensitivity enhancement of the Baryscan technique.