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281.
282.
A collaborative study on the robustness and portability of a capillary electrophoresis‐mass spectrometry method for peptide mapping was performed by an international team, consisting of 13 independent laboratories from academia and industry. All participants used the same batch of samples, reagents and coated capillaries to run their assays, whereas they utilized the capillary electrophoresis‐mass spectrometry equipment available in their laboratories. The equipment used varied in model, type and instrument manufacturer. Furthermore, different types of sheath‐flow capillary electrophoresis–mass spectrometry interfaces were used. Migration time, peak height and peak area of ten representative target peptides of trypsin‐digested bovine serum albumin were determined by every laboratory on two consecutive days. The data were critically evaluated to identify outliers and final values for means, repeatability (precision within a laboratory) and reproducibility (precision between laboratories) were established. For relative migration time the repeatability was between 0.05 and 0.18% RSD and the reproducibility between 0.14 and 1.3% RSD. For relative peak area repeatability and reproducibility values obtained were 3–12 and 9–29% RSD, respectively. These results demonstrate that capillary electrophoresis‐mass spectrometry is robust enough to allow a method transfer across multiple laboratories and should promote a more widespread use of peptide mapping and other capillary electrophoresis‐mass spectrometry applications in biopharmaceutical analysis and related fields.  相似文献   
283.
The Nordic forest industry requires just-in-time wood deliveries. Operations must continue regardless of season, weather and terrain. Soil compaction and deep ruts must be avoided while providing high performance and a reasonable working environment for operators.The Xt28 pendulum arm forwarder is a full-size concept forwarder with six hydrostatic propelled wheels on pendulum arms built on a three-piece frame connected with two articulation joints. The Xt28 concept machine was tested according to Skogforsk standard machine tests. Rut depth test focused on soil interaction where rut depth was measured related to number of passes. Machine dynamics were measured using standardized test track with focus on operator comfort.The project proved the potential of pendulum arm technology in off-road transportation. Automatic pendulum arm levelling, equalized ground pressure between wheels and improved operator comfort through reducing adverse vibrations and roll angles, simultaneously reducing dynamic forces transferred to the forest floor. Pendulum arm technology improves travel speed in adverse terrain, providing unparalleled side slope capability and enhanced productivity.  相似文献   
284.
过渡时期,我国进行了政治、经济、文化教育等方面的制度建设,建立了人民民主专政制度、人民代表大会制度、中国共产党领导的多党合作和政治协商制度,以及生产资料公有制、按劳分配制度和政治教育制度.这些制度的形成,为社会主义制度在中国的确立和完善打下了基础.  相似文献   
285.
20 0 0年 1月 1日正式实施按照国际通用惯例实行的药品分类管理制度 ,将对我国制药业的发展战略、产品结构及营销方式带来较大影响。目前举步维艰的国有制药业应结合国情 ,针对自身特点 ,调整战略 ,扬长避短 ,找准主攻方向 ;重视开发 ,抢占国内外市场 ;树立品牌 ,加大宣传力度及加强营销、提高经营服务水平 ,积极参与竞争并力争在这场高水平的竞争中成为赢家 ,从而为企业发展打开新局面。  相似文献   
286.
智能系统的综合集成研究,特别是是神经网络和专家系统这两种不同的知识表示,知识处理方法和工具的集成研究,近几年取得了很多成果和成功的应用。  相似文献   
287.
甘在会  蒋毅 《数学进展》2008,37(1):118-120
O Introduction We consider the orbital instability of standing waves for the Klein-Gordon-Zakharov system with different propagation speeds in three space dimensions  相似文献   
288.
With the advent of the supply chain management concepts, business communities have been realizing that being competitive as a single company is no longer adequate; instead, competitiveness requires consideration of all channels in the supply chain. Despite its importance, the availability of the literature addressing supply chain flexibility is still limited to date. Although relationships between various types of flexibilities have been established, the degree to which one type of flexibility affects the other types and the system performance remains to be investigated. In particular, there is a lack of rigorous analytical models elucidating the relationships between the degree of flexibility in a system and the system level of performance. In this paper, a supply chain flexibility model is developed comprising labor flexibility, machine flexibility, routing flexibility, and information technology, with total system flexibility measured by an economic index. Outputs from the model can assist in making suitable production decisions to produce multiple products under an uncertain environment. Example solutions are given. This paper can help economic evaluation when supply chain flexibility and the factors affecting flexibility are to be improved. It can also assist in making supply chain flexibility-promotion decisions.  相似文献   
289.
In this paper, we study the calibration problem for the Merton–Vasicek default probability model [Robert Merton, On the pricing of corporate debt: the risk structure of interest rate, Journal of Finance 29 (1974) 449–470]. We derive conditions that guarantee existence and uniqueness of the solution. Using analytical properties of the model, we propose a fast calibration procedure for the conditional default probability model in the integrated market and credit risk framework. Our solution allows one to avoid numerical integration problems as well as problems related to the numerical solution of the nonlinear equations.  相似文献   
290.
我国未来电信监管模式的新探索   总被引:1,自引:0,他引:1  
电信产业的快速发展和电信技术的不断创新给电信监管带来了巨大的挑战。为此,本文从分析电信业发展的趋势和由此对电信监管带来的挑战入手,在对国外电信监管模式和技术手段进行充分实证分析的基础上,从政策法律、市场准入、互连互通、资费管制、普遍服务、电信标准等六个方面探讨了我国未来电信监管模式的发展方向和发展趋势。  相似文献   
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