Growth Mechanism of IT Service Outsourcing Enterprises

与跨国IT公司合作,进行行业内知识学习和跨行业知识溢出是我国IT服务外包企业快速成长的必由之路。本文在综述知识转移过程、环境及影响因素的基础上,分析我国IT服务外包企业的知识学习和知识溢出过程,研究专业化软件开发-集成化产品-与流程结合的行业化解决方案-国际化服务交付中的知识转移特征,得出我国IT服务外包企业的成长机理模型。Knowledge learning and spillover are important tools of rapidly grow by cooperating with outstanding IT multinational enterprise for IT outsourcing vendor enterprise in China. This paper summarizes the process of knowledge transfer, exploits the function of “specialized information technology, multiple services and production, industrial solution scheme, international networking services” of IT service outsourcing enterprise, and addresses the solutions and countermeasures for policy-marker based on knowledge transfer view.国家自然科学基金(70871034);国家社会科学基金(10BTQ019);安徽大学“211”创新团队项目(SKTD010B

Ultrasonic sensing using Yb3+/Er3+-codoped distributed feedback fibre grating lasers

Yb3+/Er3+-codoped distributed feedback (YbEr-DFB) fibre grating lasers have been investigated for the detection of ultrasonic Lamb waves generated in an aluminium plate. Two sensor configurations have been investigated. A path-length-imbalanced readout Mach-Zehnder interferometer was used to measure the laser frequency shift induced by ultrasonic vibration. The resolution to out-of-plane displacement was 3 x 10(-15) m Hz(-1/2) for a continuous ultrasonic wave at a frequency of 470 kHz. Ultrasonic waves were also detected by directly monitoring the laser output power. This simplified configuration is useful for tone burst AE signals generated by a low energy impact

新型激光技术研究进展

重点介绍了过去10年来厦门大学光电子技术研究所在高Q值玻璃球微腔光子学、光纤激光器、平面波导的交错复用器设计和固体激光器研究中所取得的进展情况.特别重点讨论了在光纤激光器领域所开展的研究内容以及取得最新进展:如利用掺Yb双包层光纤激光器泵浦的2级P2O5拉曼级联获得了瓦级1 480 nm输出的拉曼光纤激光器;实现了O波段多波长磷硅拉曼光纤激光器;提出并利用双泵浦光纤参量放大器作为激光增益介质,在国际上率先实现了光通信波段(1 550 nm)多波长、窄线宽光纤参量振荡器;采用光纤激光器腔内参量泵浦技术,获得了C+L波段的高性能光纤参量放大器.同时对球微腔激光器也进行了较为详尽的讨论

Modeling based on UG Gleason spiral bevel gear

目前国内的齿轮加工专用机床无法加工一些尺寸超过其技术规格的齿轮副,而运用大型的数控加工中心加工弧齿锥齿轮副,齿轮副尺寸不再成为其制约因素。利用UG软件提供的UG/OPEN GRIP二次开发功能,编制相应的锥齿轮成形软件,根据设计图纸提供的格里森弧齿锥齿轮副的基本尺寸和参数,首先建立铣刀盘和弧齿锥齿轮大轮胚体的三维模型,然后结合格里森弧齿锥齿轮机床调整参数,在UG环境下模拟格里森机床调整过程,通过布尔运算得到成形法加工的大轮。之后采用变异的铣刀盘成形加工得到的变异大轮展成小轮毛胚实体,最终得到小轮齿面。此方法基于传统的格里森弧齿锥齿轮加工方法,又有不同之处,是格里森弧齿锥齿轮建模和加工的一种实用新方法。At present the domestic gear processing machine can not machining the gears that exceed the size of the technical specifications, in order to solve this conflict, this large-scale use of the NC processing center of spiral bevel gear, the size of the gear is no longer a constraint. With the UG/OPEN GRIP, we design bevel gear forming software to create the big round of three-dimensional model of the embryo, and complete simulation under UG, then we get the big gear by boolean operation. And a small round hair embryo is born by a variation of facer, finally, we get the tooth surface of the gear. This method is based on the traditional Gleason spiral bevel gear processing methods, also different, which suggest a practical way of a spiral bevel gear modeling and processing by Gleason.福建省重点项目(2006Y0027

In-line laser Doppler velocimeter using fibre-optic Bragg grating interferometric filters

An all fibre-based laser Doppler velocimetry system for the measurement of the predominantly on-axis component of velocity is presented. The technique employs Bragg grating-based Fabry-Perot interferometric filters custom-designed to suit the transduction of Doppler optical frequency shifts to intensity. The sensitivity of the in-fibre filters to strain is exploited to provide tuning of the filter relative to the centre wavelength of the laser and of the spectral shape of the filter, which in turn varies the velocity range, sensitivity and resolution. A phase-locking scheme incorporated to stabilize the filter is described together with a laser-wavelength stabilization system that locks to a Doppler-broadened absorption line of iodine vapour. An optical fibre-linked probe head is used to couple the laser beam at 514.5 nm to and from the measurement volume. The velocimeter is characterized by easuring the velocity of a rotating disc over ranges of +/-42 and +/-7 m s(-1) with a resolution of 0.2 m s(-1)

Characterization of the response of fibre Bragg gratings fabricated in stress and geometrically induced high birefringence fibres to temperature and transverse load.

The transverse load and temperature sensitivities of fibre Bragg gratings (FBGs) fabricated in a range of commercially available stress and geometrically induced high birefringent (HiBi) fibres have been experimentally investigated. The wavelength reflected by the FBG in each polarization eigenmode was measured independently and simultaneously using a custom designed interrogation system. The highest transverse load sensitivity, of 0.23 ± 0.02 nm/(N/mm), was obtained with HiBi FBGs fabricated in elliptically clad fibre. This was higher than for any other HiBi fibre, which, coupled with the small diameter of the fibre, makes it a good candidate for an embedded or surface mounted strain sensor. The highest temperature sensitivity of 16.5 ± 0.1 pm °C-1, approximately 27% greater than any other fibre type, was obtained with the HiBi FBG fabricated in Panda fibre. HiBi FBG sensors fabricated in D-clad fibre were the only ones to exhibit identical temperature sensitivities for the slow and fast axes (11.5 ± 0.1 pm

Simultaneous temperature and bend sensing with long-period fiber gratings

Long-period gratings (LPG's) written in commercially available boron-codoped fibers operating at wavelengths of <1.1 mu m are shown to exhibit high temperature and bending sensitivities. Each resonant attenuation band of such LPG's was observed to split in two when the LPG's were bent. The split attenuation bands' separation increased significantly with increasing bend curvature, and the central wavelengths of the split bands provided a measure of temperature. We exploit this effect to allow for simultaneous measurement of temperature and bending in smart-structure applications. The demonstrated novel sensor system is simple and low cost. (C) 2000 Optical Society of America OCIS codes: 060.2370, 350.2770

Applications of polymer optical fibre grating sensors to condition monitoring of textiles

Fibre Bragg gratings (FBGs) in polymer optical fibres (POFs) have been used to measure the strain in a woven textile. FBGs in both POFs and silica optical fibres were attached to a woven textile specimen, and their performance characterised. It was demonstrated that the POF FBGs provide improved strain transfer coefficients and reduce local structural reinforcement compared to silica FBGs and therefore make a more suitable proposition for textile monitoring

Kilogram Scale-up Preparation of Catalysts and its Reaction Process in Syngas Methanation

甲烷化催化剂是煤制合成天然气核心技术之一,因此研发合成气完全甲烷化催化剂具有重要意义。研究工作采用实验室小试共沉淀制备甲烷化催化剂的最佳工艺条件; 方法,进行单批次1、5和10; kg级(代号cat-1、cat-5、cat-10)催化剂的制备研究。研究了催化剂制备的控制因素和放大制备催化剂的反应性能及催化反应工艺条件。研究; 显示:催化剂制备的控制因素主要包括Na~+含量及晶型结构;放大制备催化剂具有良好的活性、操作稳定性和耐热性能,与小试制备催化剂具有较好的一致性;; 放大制备催化剂(cat-10)在所考察的还原温度、反应H_2/CO比和10000~40000; mL·h~(-1)*g_(cat)~(-1)反应空速范围内具有良好的甲烷化活性。研究结果表明,该研究单批次公斤级催化剂放大制备是成功的,为实现催; 化剂进一步放大制备提供了良好基础。Methanation catalysts play a vital role in the production of synthetic; natural gas (SNG) from coal. Based on bench-scale optimum; co-precipitation conditions of catalyst preparation, scale up; preparation of catalysts for syngas methanation with single batch of 1,; 5 and 10 kg is studied. Factors affecting catalyst; preparation/performance and scale-up were investigated. The results show; that Na~+ content and crystal structure of the catalysts are the; critical factors, and the catalysts prepared under scale-up conditions; possess excellent operation stability and heat resistance, with; consistent performance as those from bench-scale samples. The 10 kg; batch has good reaction activity under studied conditions. Therefore,; the scale-up preparation is successful for the methanation catalyst in; this study, which is useful for future scale-up preparation of related; catalysts

Proposal for an Er3+-doped chalcogenide glass fiber upconversion laser operating at 980 nm and pumped at 1480 nm

We propose a novel fiber upconversion laser operating at 980 nm and pumped at 1480 nm, which will allow remote optical pumping of erbium-doped optical amplifiers, From the measured spectroscopy, we show Er3+-doped gallium lanthanum sulphide glass to be a potential host for such a 1480-nm/980-nm upconversion laser. The small-signal gain is analyzed numerically and the lasing possibilities are discussed