开创信息安全服务时代

靠服务打天下,把服务看作是信息安全的一个广阔天地,这是众多安全厂商的共识。近些年来,各路信息安全厂商纷纷开展信息安全服务—国内专业从事安全服务的厂商已达上百家,国外在我国开展这一业务的厂商也有上十家。目前几乎没有一个安全厂商不宣称自己能提供专业的信息安全服务,安全服务已成为安全厂商推广业务的不可或缺的一个招牌。专业机构把这种变化称为信息安全已发展到了从“以提供产品为主到同时提供产品和服务的阶段”。今年国信办等部门在全国范围内大力推行风险评估工作,这为信息安全服务创造了一个绝好的发展机遇。不仅如此,在今…     

杀毒厂商从单机版迈向网络化

从金山毒霸的“安全体验风暴”到瑞星的“网络版3周年庆典”,再到江民的“999元反病毒运动”,众厂商如此活动的目标只有一个——网络化     

营造绿色奥运通信 网秦手机安全护航

近日,为期两天的“2008阳光绿色网络研讨会”在北京京都信苑酒店举行。本次会议的主题为“构建安全信息网络、助力绿色科技奥运”,而“绿色奥运”概念则贯穿于整个大会的始终。 作为国内最具知名度且市场占有率最高的手机安全服务企业——北京网秦天下科技有限公司,在本次会议的“服务奥运,营造健康向上的网络环境”专题中进行了题为“网秦垃圾短信反骚扰方案”的演讲。     

网络战也需要“红绿灯”

[前言]在本刊连续9期刊登资深安全专家谈“网络战”的专题之后，本期国内知名安全厂商启明星辰也参与到“网络战”这个话题中来。在这一期。启明星展的安全专家翟胜军分析了国内外“网络战”的异同，并将网络战从国家间的政治时抗延伸到人们生活中的安全攻击与防御中来。他提出了一个新颖的观点。他认为网络世界最大的特点不是连通，而是开放，有了它海纳百川的“胸怀”，人们才可以迅速融入世界的每个角落。     

2011年运营商安全防护成效显著 增值业务或成新安全挑战

4月6日,由人民邮电出版社举办的"第四届通信网络和信息安全高层论坛"在京召开。据了解本次论坛得到了工信部和三大运营商的大力支持,包括华为、Websense、安天、绿盟科技、恒安嘉新、国舜科技、北信源软件、天存信息、安码科技、启明星辰、杭州安恒等多家安全服务厂商和研发机构参与,会议盛况超越前三届,这显示出通信行业所面临的安全挑战越来越复杂。     

手机的安全威胁与解决之道

随着性能的提升和应用的丰富,手机面临着越来越多的安全问题。如何在满足用户对手机性能要求的同时,提升手机安全性能成为当前业界关注的重点之一。手机面临哪些安全威胁,如何提升手机安全性能？在“2009通信网络和信息安全高层论坛”举办期间,本刊记者采访了北京网秦天下科技有限公司（以下简称“网秦”）副总裁卢竞,请他就手机安全问题介绍了网秦的观点。     

安全是目标实现靠服务

2003年，“安全服务”就被众多的安全厂商看作是新的生机和商机，然而8年过去了，中国的信息安全服务产业发展究竟怎样呢？全球IT服务随着IT业的发展大致由最初的“产品阶段”到“解决方案”阶段，最后才到“IT服务”阶段，信息安全服务也是如此。     

网秦发布永久免费的“网秦手机卫士”

5月21日,手机安全公司网秦宣布,近期将推出完全免的安全产品——网秦“手机卫士”。该产品将为手机用户的安防护提供全新的“一站式”安全保障。     

"入侵"网络安全的新军

在经历了初期安全厂商如赶时尚般纷纷投资进入市场,到部分企业禁不起市场残酷的洗礼,不断地被淘汰之后,今年电子政务的燎原之火又为信息安全领域燃起了新的希望。而今年安全业的心声,可谓“一半是海水,一半是火焰”。我们看到,在众厂商的霍霍刀声中,一些追思者眼里不时闪出的刀光剑影,为我们折射出“曾经沧海难为水”的苦涩;而在声势浩荡的安全大军中,又不断现出新     

“古墓丽影”的终结者 网秦天下服务再升级

网秦是一家专注于移动安全的厂商,_直在努力提升客户服务品质,增强用户体验。新的呼叫中心上线后规模扩充到数十条电话线路,为及时详尽地处理用户咨询奠定了硬件基础。呼叫中心的启用,标志着网秦进一步将“以用户为中心”的理念融入企业运营中。     

Monolithically integrated, photoreceiver with large, gain-bandwidth product

A direct-detection 800 nm GaAs monolithically integrated photoreceiver is reported with a photocurrent gain of 200 and a 1 GHz bandwidth capable of driving a 50 ? load with IV peak pulses. The integrated NPN photodiode has over 7GHz bandwidth and requires no modifications to the ion-implanted GaAs MESFET process. The 200GHz gain-bandwidth product and 3200 V/W responsivity are among the highest reported for similar receivers.     

Comments, with reply, on `Optimal respiratory controllerstructures''

The commenter points out several defects in the modified respiratory controller model described in the above paper (ibid., vol.BME-33, p.677-80, 1986). He argues that: (1) the assumption of additive response characteristics is problematic, (2) the proposed additive controller structure is inherently redundant and unnecessary, and (3) these ambiguities aside, an alternative additive-type optimal controller model exists which has a different neuronal structure than the one described by the authors, i.e. the additive controller structure is not unique. The authors provide a counterargument     

Multifunctional Ionic Skin with Sensing,UV-Filtering,Water-Retaining,and Anti-Freezing Capabilities

Conductive polymer hydrogels are receiving considerable attention in applications such as soft robots and human-machine interfaces. Herein, a transparent and highly ionically conductive hydrogel that integrates sensing, UV-filtering, water-retaining, and anti-freezing performances is achieved by the organic combination of tannic acid-coated hydroxyapatite nanowires (TA@HAP NWs), polyvinyl alcohol (PVA) chains, ethylene glycol (EG), and metal ions. The highly ionic conductivity of the hydrogel enables tensile strain, pressure, and temperature sensing capabilities. In particular, in terms of the hydrogel strain sensors based on ionic conduction, it has high sensitivity (GF = 2.84) within a wide strain range (350%), high linearity (R² = 0.99003), fast response (≈50 ms) and excellent cycle stability. In addition, the incorporated TA@HAP NWs act as a nano-reinforced filler to improve the mechanical properties and confer a UV-shielding ability upon the hydrogel due to its size effect and the characteristics of absorbing ultraviolet light waves, which can reflect and absorb short ultraviolet rays and transmit visible light. Meanwhile, owing to the water-locking effect between EG and water molecules, the hydrogel exhibits freezing resistance at low temperatures and moisture retention at high temperatures. This biocompatible and multifunctional conductive hydrogel provides new ideas for the design of novel ionic skin devices.     

Mode-locked, long-cavity, erbium fiber lasers with subsequentsoliton-like compression

Erbium fiber lasers are described that have cavity lengths of 20-5000 m and are mode-locked at the fundamental cavity frequency using an integrated-optic intensity modulator driven by a novel pulse generator. Resulting optical pulses at 1536 nm were recorded with a synchroscan streak camera and show durations of 10-80 ps with peak powers over 6 W. The shorter cavities yield nearly transform-limited pulses, which are narrowed by solitonlike compression to approximately 5 ps after propagation through an external 14 km fiber     

国产基础软件标准化——与研发、测试、应用的互动

基础软件在现代信息处理应用中起着基础性的支撑作用,标准在国产基础软件的发展中扮演着重要的角色.在已进行的标准化工作中,充分实现与产品技术研发、应用系统构建与测试环境建设的紧密互动,并取得了重要的成果:建立了国产基础软件技术规范体系,制定了一系列关键规范,建设了基于规范的符合性和集成测试环境.这些成果通过实际应用系统得到了验证.与研发、测试、应用互动的标准化实践为今后的相关工作提供了有用的参照.     

Parallel,self-organizing,hierarchical neural networks with forward-backward training

A forward-backward training algorithm for parallel, self-organizing hierarchical neural networks (PSHNNs) is described. Using linear algebra, it is shown that the forward-backward training of ann-stage PSHNN until convergence is equivalent to the pseudo-inverse solution for a single, total network designed in the least-squares sense with the total input vector consisting of the actual input vector and its additional nonlinear transformations. These results are also valid when a single long input vector is partitioned into smaller length vectors. A number of advantages achieved are: small modules for easy and fast learning, parallel implementation of small modules during testing, faster convergence rate, better numerical error-reduction, and suitability for learning input nonlinear transformations by other neural networks. The backpropagation (BP) algorithm is proposed for learning input nonlinearitics. Better performance in terms of deeper minimum of the error function and faster convergence rate is achieved when a single BP network is replaced by a PSHNN of equal complexity in which each stage is a BP network of smaller complexity than the single BP network.     

Impulse generation with appropriate amplitude, length,inter-arrival, and spectral characteristics

This paper proposes a suitable method for simulating impulses with appropriate amplitude, spectral, and inter-arrival characteristics. The statistics used to develop the parameters of this model are based on statistics derived from observations of impulse noise on the telephone networks of British Telecom (BT) and Deutsche Telekom (DT). This paper initially reviews the former DT approach to impulse noise generation for testing digital subscriber line systems, so called xDSL systems. Some problems are highlighted and an alternative technique is suggested that is capable of generating impulses with both appropriate amplitude an spectral characteristics     

Computerized tomography with X-ray, emission, and ultrasound sources

This paper reviews the major developments that have taken place during the last three years in imaging with computed tomography (CT) using X-ray, emission, and ultrasound sources. Space limitations have resulted in some selection of topics by the author. There are four major sections dealing with algorithms, X-ray CT, emission CT, and ultrosound CT. Since most of the currently used algorithms are of filtered-backprojection type, we have concentrated on these in the section on algorithms (with emphasis on their implementation aspects). In X-ray CT an important question raised during the last few years has concerned the parameter measured by a CT scanner, given the fact that the X-rays used in CT scanners are polychromatic and the fact that tissue attenuation coefficients are energy dependent. Answers to this question are reviewed in the section on X-ray CT where we have also discussed the artifacts caused by the polychromaticity of the X-ray photons. Methods for the removal of these artifacts have also been reviewed. In emission CT the biggest development of the last three years is the great interest in positron tomography, although space constraints have dictated an essentially introductory treatment and not all aspects of the single photon and positron tomography have been surveyed. Finally, we have reviewed recent developments in ultrasound CT. We have pointed out that because of the sensitivity of this technique to refraction, it is currently limited to soft tissue structures, with ultrasonic detection of tumors in the female breast a significant application.     

A new, soft-switched, high-power-factor boost converter with IGBTs

A new soft-switching technique that improves performance of the high-power-factor boost rectifier by reducing switching losses is introduced. The losses are reduced by an active snubber which consists of an inductor, a capacitor, a rectifier, and an auxiliary switch. Since the boost switch turns off with zero current, this technique is well suited for implementations with insulated-gate bipolar transistors. The reverse-recovery-related losses of the rectifier are also reduced by the snubber inductor which is connected in series with the boost switch and the boost rectifier. In addition, the auxiliary switch operates with zero-voltage switching. A complete design procedure and extensive performance evaluation of the proposed active snubber using a 1.2 kW high-power-factor boost rectifier operating from a 90 V_rms-256 V_rms input are also presented     

Functionalized Polyurethane-Coated Fabric with High Breathability,Durability, Reusability,and Protection Ability

Transmission of pathogens via respiratory droplets can spread infections such as COVID-19. Wearing a mask hinders the spread of COVID-19 infection and has become mandatory in some cases. Although most masks are affordable and disposable, continual daily replacement is required due to their performance deterioration caused by washing and contamination. Hence, a urethane-reactive coating material comprising perfluoro-tert-butanol-hexamethylene diisocyanate is developed with highly hydrophobic and oleophobic properties to functionalize a polyurethane-coated fabric to bestow high breathability, durability, reusability, and protection ability. Its functions are maintained after scratch and wash testing, and its air permeability and water vapor transmittance rate (necessary for respiration) are unaffected. Its filtration efficiency of water droplets containing 100 nm polystyrene particles (similar in size to SARS-CoV-2) is increased due to its highly hydrophobic properties. In addition, it inhibits the adsorption of bovine serum albumin, the spike protein of COVID-19, and Staphylococcus aureus and Pseudomonas aeruginosa.