谈谈光子计算机

 1946年计算机的诞生是上世纪科学技术发展划时代的伟大成就之一,它的出现和发展极大地提高了人类处理信息的效率,从而促进了劳动生产力的极大解放。计算机的发展与普及改变了人们的工作方式和生活方式,已成为人们生活和工作的必备品。然而现在使用的计算机均为电子计算机,随着光子学和光子技术的发展,必将产生一种新型的计算机---光子计算机。本文简要谈谈光子计算机。一、光子计算机及其特点光子计算机是一种全新的计算机,是以光子作为主要的信息载体,以光子系统作为计算机的主体,以光运算作为计算机运算方式的计算机。     

基于RFID技术的计算机身份认证系统设计

随着信息时代的发展,计算机得到了广泛应用,计算机中的信息安全成为一个极为重要的问题;针对计算机的性息泄漏问题,设计了基于RFID技术的计算机身份认证系统;系统由USB-Lock和无线Key两个硬件设备和软件组成,当无线Key处在USB-Lock的感应区域时,双方保持通信,计算机处于可用状态;当无线Key超出USB-Lock的感应区域时,双方通信中断,计算机进入不可用状态,当用户回到计算机附近时,双方通信得到恢复实现计算机信息保护。     

在线计算机与核技术应用

一、引 言 由于小型计算机和微计算机的迅速发展,计算机在线技术得到迅速的发展,小型计算机和微计算机具有功能强、灵活、体积小、可靠性高等许多优点,在核技术应用的在线数据获取和处理、过程自动控制以及仪器仪表的智能化等方面得到愈来愈多的应用. 将计算机在线技术用于实验     

计算机3D立体图的设计和制造

介绍了计算机３Ｄ立体图的分类和基本原理，给出了计算机３Ｄ立体图的设计制造过程，讨论了计算机３Ｄ立体图的应用前景和发展方向     

计算机实验室与应用型创新人才培养探讨

计算机实验室承担大学生在计算机上做实验的基础课、专业课、选修课和学科竞赛等各专业实验教学任务。通过对实验室在高校创新人才培养中存在问题和重要性进行分析,以计算机实验室为例研究了实验室与应用型创新人才培养之间的关系,以培养大学生计算机的综合应用能力和创新能力为目标的开放、互联、共享计算机实验室对应用性创新人才培养发挥了重要作用。     

浅析光量子计算机中的物理原理和教育意义

光量子计算机是基于量子相干叠加原理和光学技术而实现的一种具有超快的并行计算和模拟能力的计算机.近几年,我国在光量子计算机领域不断取得重大突破,处于国际领先地位.光量子计算机是国家前沿技术重大成就的代表,涉及到众多经典物理学、光学和量子力学的知识,具有着重要的教育意义.     

利用传感器研究电容器的充电和放电

DISLab新型数字化实验系统是由“传感器＋数据采集器＋实验软件包＋计算机”构成的．数字化实验系统是信息技术与传统实验课程整合的重要载体．基于传感器的计算机实时数据采集和基于计算机数据处理软件的计算机建模和图像分析等技术是开展现代化中学物理探究教学的两大技术支撑,     

神经回路计算机

 制造计算机所采用的元件在发展和更新,人们依据制造计算机所采用的元件不同,将计算机划分为不同的代。从采用电子管元件制造的计算机到利用超大规模集成电路(VLSI)设计的计算机,计算机历经了几代发展。     

基于RFM的机载余度计算机软件快速测试平台

现代飞机普遍采用电传飞行控制系统,飞行控制计算机是该系统的核心。为了提升飞控计算机的可靠性,普遍采用余度技术构建余度飞控计算机,该计算机由多个通道构成,每个通道有一个CPU,互相构成备份。但是,这给飞控计算机的软件调试和测试带来的巨大的困难,因为各个通道的机载软件之间相互同步、通信和交叉监控,必须并行调试和测试,这就造成了机载软件调试和测试的滞后,必须等待真实的飞控计算机开发出来之后才能开展工作。本文提出了一种基于RFM(反射内存)的余度计算机快速原型测试平台设计方法。该平台使用商用货架产品构成余度计算机的多个冗余通道,使用RFM模拟多通道间的通信、同步过程,通过对底层驱动封装实现硬件故障模拟和余度功能模拟,方便实现软件调试和从性能、功能测试,大大提高了开发效率,减少了研制周期。     

计算机通信网络的防雷技术

鉴于近年来计算机通信网络遭受雷击损坏的情况日益严重，因此如何对计算机通信网络实施切实有效的防雷保护，保证系统安全可靠的运行，成为当前一项紧迫的重要课题．本文首先通过对计算机通信网络系统遭受雷击损坏的情况进行统计调查和现场勘测，以及对其相应电路模型的理论分析和模拟试验论证，较详细地分析了计算机通信网络系统遭受雷击损害的主要原因以及可能的侵入途径．在此基础上，介绍了如何通过模拟雷电冲击试验对计算机通信网络接口的雷电冲击伏－安特性进行测试研究，为制定计算机通信系统保护方案提供数据依据．最后，文章重点阐述了计算机通信网络系统的防雷保护方案，其中主要介绍了计算机通信网络接口或通信设备的防雷装置及其安装要求以及通信网络线路和地线回路的布放方式、相应的屏蔽措施等方面的问题．     

Stokes integral of economic growth: Calculus and the Solow model

Economic growth depends on capital and labor and two-dimensional calculus has been applied to economic theory. This leads to Riemann and Stokes integrals and to the first and second laws of production and growth. The mathematical structure is the same as in thermodynamics, economic properties may be related to physical terms: capital to energy, production to physical work, GDP per capita to temperature, production function to entropy. This is called econophysics. Production, trade and banking may be compared to motors, heat pumps or refrigerators. The Carnot process of the first law creates two levels in each system: cold and hot in physics; buyer and seller, investor and saver, rich and poor in economics. The efficiency rises with the income difference of rich and poor. The results of econophysics are compared to neoclassical theory.     

Ohmic Contacts to ZnSe-Based Materials

The formation of ohmic contacts to n- and p-type ZnSe is reviewed. The mechanisms for forming reasonable low-resistance ohmic contacts to n-ZnSe are well understood. This results from the fact that the Fermi energy level of ZnSe is unpinned and metals with sufficiently large work functions can make contact to n-type material. However, the situation is reversed for p-ZnSe where a large band gap and large electron affinity make it impossible to find metals with sufficiently large work functions to create an ohmic contact. Instead, the use of HgSe to form low barrier height Schottky contacts and of ZnSe/ZnTe multiple quantum wells (MQWs) to form ohmic contacts is reviewed. Although the MQWs can be used to form ohmic contacts to p-ZnSe, they degrade at high temperatures and high current densities. This is reviewed and shown to be a serious problem for applications to laser diodes.     

Numbers,scale and symbols: the public understanding of nanotechnology

Nanotechnology will be an increasing part of the everyday lives of most people in the world. There is a general recognition that few people understand the implications of the technology, the technology itself or even the definition of the word. This lack of understanding stems from a lack of knowledge about science in general but more specifically difficulty in grasping the size scale and symbolism of nanotechnology. A potential key to informing the general public is establishing the ability to comprehend the scale of nanotechnology. Transitioning from the macro to the nanoscale seems to require an ability to comprehend scales of one-billion. Scaling is a skill not common in most individuals and tests of their ability to extrapolate size based upon scaling a common object demonstrates that most individuals cannot scale to the extent needed to make the transition to nanoscale. Symbolism is another important vehicle to providing the general public with a basis to understand the concepts of nanotechnology. With increasing age, individuals are able to draw representations of atomic scale objects, but these tend to be iconic and the different representations not easily translated. Ball and stick models are most recognized by the public, which provides an opportunity to present not only useful symbolism but also a reference point for the atomic scale.     

Review of LDA and PIV applied to the measurement of sound and acoustic streaming

A review of laser Doppler anemometry (LDA) and particle image velocimetry (PIV) with their application to the measurement of sound is presented. The fundamental principles behind LDA and PIV are discussed and extended to the application of sound measurement. Special attention is paid to analysis of LDA signals including the Hilbert transform, which enables amplitude information to be obtained about various frequency components of a signal and wavelet analysis, which allows non-stationary signals to be accurately analysed. The influence of the refractive index variations in a medium due to a sound wave on the laser beams of an LDA signal is discussed. Attention is also paid to acoustic streaming which arises due to high-intensity sound, and PIV results are presented to demonstrate the effect.     

多元可激发气体声弛豫频率的环境影响分析

推导多元可激发气体中声弛豫频率和环境温度、压强的解析关系.理论分析和仿真计算表明：声弛豫频率线性反比于主弛豫过程的弛豫时间,正比于主弛豫过程的振动耦合热容,反比于外自由度热容;温度升高导致振动耦合热容增加、内外自由度能量转移速率增大引起弛豫时间减少,进而造成声弛豫频率正比于环境温度;压强增加使得分子碰撞速率增加引起弛豫时间减少,进而使得声弛豫频率线性正比于环境压强.     

Thermo-chemical modelling of a village cookstove for design improvement

Cookstove operation comprises three basic processes, namely combustion of firewood, natural air draft due to the buoyancy induced by the temperature difference between the hearth and its surroundings, and heat transfer to the pot, stove body and surrounding atmosphere. Owing to the heterogenous and unsteady burning of solid fuel, there exist nonlinear and dynamic interrelationships among these process parameters. A steady-state analytical model of the cookstove operation is developed for its design improvement by splitting the hearth into three zones to study char combustion, volatile combustion and heat transfer to the pot bottom separately. It comprises a total of seven relations corresponding to a thorough analysis of the three basic processes. A novel method is proposed to model the combustion of wood to mimic the realities closely. Combustion space above the fuel bed is split into 1000 discrete parts to study the combustion of volatiles by considering a set of representative volatile gases. Model results are validated by comparing them with a set of water boiling tests carried on a traditional cookstove in the laboratory. It is found that the major thrust areas to improve the thermal performance are combustion of volatiles and the heat transfer to the pot. It is revealed that the existing design dimensions of the traditional cookstove are close to their optimal values. Addition of twisted-tape inserts in the hearth of the cookstove shows an improvement in the thermal performance due to increase in the heat transfer coefficient to the pot bottom and improved combustion of volatiles.     

Two-dimensional detector software: From real detector to idealised image or two-theta scan

Abstract

Detector systems introduce distortions into acquired data. To obtain accurate angle and intensity information, it is necessary to calibrate, and apply corrections. Intensity non-linearity, spatial distortion, and non-uniformity of intensity response, are the primary considerations.

It is better to account for the distortions within scientific analysis software, but often it is more practical to correct the distortions to produce ‘idealised’ data.

Calibration methods and software have been developed for single crystal diffraction experiments, using both approaches. For powder diffraction experiments the additional task of converting a two-dimensional image to a one-dimensional spectrum is used to allow Rietveld analysis. This task may be combined with distortion correction to produce intensity information and error estimates.

High-pressure experiments can introduce additional complications and place new demands on software. Flexibility is needed to be able to integrate different angular regions separately, and to produce profiles as a function of angle of azimuth. Methods to cope with awkward data are described, and examples of the techniques applied to data from high pressure experiments are presented.     

Inactivation of the enveloped virus phi6 with hydrodynamic cavitation

The COVID −19 pandemic reminded us that we need better contingency plans to prevent the spread of infectious agents and the occurrence of epidemics or pandemics. Although the transmissibility of SARS-CoV-2 in water has not been confirmed, there are studies that have reported on the presence of infectious coronaviruses in water and wastewater samples. Since standard water treatments are not designed to eliminate viruses, it is of utmost importance to explore advanced treatment processes that can improve water treatment and help inactivate viruses when needed. This is the first study to investigate the effects of hydrodynamic cavitation on the inactivation of bacteriophage phi6, an enveloped virus used as a SARS-CoV-2 surrogate in many studies. In two series of experiments with increasing and constant sample temperature, virus reduction of up to 6.3 logs was achieved. Inactivation of phi6 at temperatures of 10 and 20 °C occurs predominantly by the mechanical effect of cavitation and results in a reduction of up to 4.5 logs. At 30 °C, the reduction increases to up to 6 logs, where the temperature-induced increased susceptibility of the viral lipid envelope makes the virus more prone to inactivation. Furthermore, the control experiments without cavitation showed that the increased temperature alone is not sufficient to cause inactivation, but that additional mechanical stress is still required. The RNA degradation results confirmed that virus inactivation was due to the disrupted lipid bilayer and not to RNA damage. Hydrodynamic cavitation, therefore, has the potential to inactivate current and potentially emerging enveloped pathogenic viruses in water at lower, environmentally relevant temperatures.     

Improving the adhesion between a aqueous PU and a polyamide fibre with silane

Glycidoxypropyltrimethoxysilane (GPS) and γ-aminopropyltrimethoxysilane (APS) were used to modify the surface chemistry of polyamide fibre. The surface chemistry was characterised using X-ray photoelectron spectroscopy. The silanol functional group was designed to be introduced on the surface of polyamide fibre to increase its chemical activity by N-alkylation of GPS and hydrolysis of APS, and to improve the poor interfacial adhesion between a polyamide 66 fibre and an aqueous polyurethane polymer adhesive. The microbond test was used to measure the interfacial shear strength between the waterborne PU adhesive and the polyamide fibre. It has been found that APS hydrolysis and GPS-alkylated fibre surface can be used to improve the interfacial adhesion of polyamide fibre to PU. The IFSS can be improved by N-alkylation of GPS from 5.0 to 8.4?MPa. After water immersion at 50?°C for 48?h, then drying, the IFSS increased to 8.8?MPa due to the plasticisation of PU in water. Better interfacial adhesion was also observed by the hydrolysis of APS, but not significantly improved by this method due to the relatively weak hydrogen bond at the interface between APS and polyamide fibre.     

Molecular dynamics study of configuration and stability of vacancy clusters in fcc Ag

Vacancies may agglomerate to form vacancy Frank loops of different shapes, as observed by transmission electron microscopy in quenched and irradiated fcc metals. The dynamics for the dissociation of vacancy Frank loops and the subsequent evolution of defect nanostructures were explored by means of the molecular dynamics method and displayed by the local crystalline order method. Frank loops of different initial shapes were found to transform to a variety of defect nanostructures: triangle to stacking fault tetrahedra, equilateral hexagon to quasi-heptahedron, and scalene hexagon to various intermediate structures depending on the length of the short side. The formation energies for vacancy Frank loops of different geometries are introduced to categorize various final configurations. Crystallographic analysis and elasticity calculations were performed to elucidate the transform mechanisms in fcc Ag.