“新时期统计文化建设研讨会”综述

统计文化是一种行业性的亚文化,是科学文化与人文文化的结合。在新的历史时期,统计文化有着丰富的内涵和表现形式,其中深层次的精神文化居于核心地位。统计文化对统计人员的影响往往体现在统计职业道德之中。统计文化建设是一项复杂的系统工程,必须坚持以人为本。     

雷达仿真系统中电磁干扰环境的仿真设计和实施

雷达仿真系统是为检测雷达设备的抗干扰能力以及在各种电磁环境下的工作性能而设计的，包括有源干扰和无源干扰的模拟仿真。本文阐述了无源干扰即杂波的散射模型和仿真过程；从同步脉冲干扰的基本原理出发，阐明在雷达工作环境仿真系统中距离拖引、速度拖引、虚假目标等同步脉冲有源干扰的设计和实施过程；并针对工作在搜索和跟踪交替模式下的相控阵雷达提出自适应综合干扰方式；最后分析并总结了系统仿真时为真实、有效地模拟电磁干扰环境应注意的关键问题。     

Influence of gas composition on recurrence of atelectasis after a reexpansion maneuver during general anesthesia

BACKGROUND: Atelectasis, an important cause of impaired gas exchange during general anesthesia, may be eliminated by a vital capacity maneuver. However, it is not clear whether such a maneuver will have a sustained effect. The aim of this study was to determine the impact of gas composition on reappearance of atelectasis and impairment of gas exchange after a vital capacity maneuver. METHODS: A consecutive sample of 12 adults with healthy lungs who were scheduled for elective surgery were studied. Thirty minutes after induction of anesthesia with fentanyl and propofol, the lungs were hyperinflated manually up to an airway pressure of 40 cmH2O. FIO2 was either kept at 0.4 (group 1, n = 6) or changed to 1.0 (group 2, n = 6) during the recruitment maneuver. Atelectasis was assessed by computed tomography. The amount of dense areas was measured at end-expiration in a transverse plane at the base of the lungs. The ventilation-perfusion distributions (VA/Q) were estimated with the multiple inert gas elimination technique. The static compliance of the total respiratory system (Crs) was measured with the flow interruption technique. RESULTS: In group 1 (FIO2 = 0.4), the recruitment maneuver virtually eliminated atelectasis for at least 40 min, reduced shunt (VA/Q < 0.005), and increased at the same time the relative perfusion to poorly ventilated lung units (0.005 < VA/Q < 0.1; mean values are given). The arterial oxygen tension (PaO2) increased from 137 mmHg (18.3 kPa) to 163 mmHg (21.7 kPa; before and 40 min after recruitment, respectively; P = 0.028). In contrast to these findings, atelectasis recurred within 5 min after recruitment in group 2 (FIO2 = 1.0). Comparing the values before and 40 min after recruitment, all parameters of VA/Q were unchanged. In both groups, Crs increased from 57.1/55.0 ml.cmH2O-1 (group 1/group 2) before to 70.1/67.4 ml.cmH2O-1 after the recruitment maneuver. Crs showed a slow decrease thereafter (40 min after recruitment: 61.4/60.0 ml.cmH2O-1), with no difference between the two groups. CONCLUSIONS: The composition of inspiratory gas plays an important role in the recurrence of collapse of previously reexpanded atelectatic lung tissue during general anesthesia in patients with healthy lungs. The reason for the instability of these lung units remains to be established. The change in the amount of atelectasis and shunt appears to be independent of the change in the compliance of the respiratory system.     

前馈和反馈相结合的控制策略在宝钢线材厂控冷轧线上的应用实践

在详细分析料坯在水箱内冷却热过程特点的基础上，提出了前馈和反馈相结合的水流量优化控制策略，并将该策略应用于宝钢线材厂控冷轧线上。实际运行结果表明：该策略能够合理地控制水箱水流量，从而保证了线材水箱出口处的温度满足工艺要求，大大提高了线材成品的质量。所做工作对国内同类企业有重要的意义。     

光纤的淬冷增强原理

本文从拉丝工艺技术的角度出发，讨论了高速、高温拉丝工艺方法对光纤的淬冷增强原理。     

Penicilloyl peptides are recognized as T cell antigenic determinants in penicillin allergy

Although hapten immune responses have been intensively studied in the mouse, very little is known about hapten determinants involved in human allergic reactions. Penicillins, as chemically reactive compounds of low molecular weight, constitute typical examples of hapten allergens for humans. Penicillins become immunogenic only after covalent binding to carrier proteins and in this form frequently induced IgE-mediated allergic reactions in patients subjected to antibiotic treatment. However, our previous data strongly indicated that penicillins also form part of the epitopes contacting the antigen receptors of beta lactam-specific T cells in allergic individuals. We have therefore investigated the molecular constraints involved in the T cell immune response to penicillin G (Pen G). Designer peptides containing a DRB1*0401-binding motif and covalently modified with Pen G via a lysine epsilon-amino group were found to induce proliferation of Pen G-specific T cell clones. A precise positioning of the hapten molecule on the peptide backbone was required for optimal T cell recognition. Furthermore, we extended these observations from our designer peptides to show that a peptide sequence derived from a natural DRB1*1101-binding peptide modified in vitro with Pen G, also acquired antigenic properties. Our data for the first time provide insight into the manner in which allergenic haptens are recognized by human T cells involved in allergic reactions to drugs and suggest possible mechanisms leading to the onset of these adverse immune responses.     

与客户建立互惠互利长期稳定的营销关系

在我国加入WTO之后，国内钢铁企业与经销商之间如何实现互惠互利，并建立起长期稳定的营销关系。     

大型软件缺陷修正跨国外包后的质量控制

研究了大型软件A93K SOC Series 93000缺陷修正在跨国外包后的质量控制问题,提出了采用缺陷跟踪和缺陷检查的解决方案;并通 过缺陷修正数量和工作流服务质量等指标的分析,论证了CRT(Customer Response Team)质量控制的有效性;得到了综合评价缺陷修正质量控 制成效的一个重要技术指标,即缺陷修正比率FROC(Fixing Rate of CR)。