污水处理CASS工艺中自控系统的设计

本文作者完成几个采用CASS工艺的污水处理工程的自控系统设计，就中小污水处理工程中采用CASS工艺，根据国内情况，而对应的自控系统的设计和设备的选型较为详细叙述．     

机械制造工艺数字化建模与网络化设计工具系统的研究

结合某大型汽轮机厂网络化工艺设计与过程管理集成系统的研制，针对面向产品工艺设计、过程管理与信息资源一体化的制造业信息化集成的需要，提出了面向产品与过程管理的制造工艺集成系统的集成模型，根据用户权限的不同，在工艺设计部门，采用C/S模式，集工艺设计、资源管理、文档管理与工艺管理为一体，实现工艺设计和管理的计算机化和信息化，在工艺设计部门以外与工艺工作有关的所有部门，采用B／S模式，实现工艺信息的共享与协同处理，解决了制造业信息化工程建设中制造工艺信息平台系统构建的关键技术问题。     

工艺数据模型的研究

一、引言 CAPP系统围绕工艺数据来解决企业的工艺设计问题,工厂依据工艺数据来安排和组织生产。首先,生成零件工艺规程要以大量的工艺数据为基础,其次,CAPP系统中产生的大量工艺数据要提供给工厂其他设计部门或管理部门使用,或者提供给NCP、PDM、MRP等系统使用。在CAPP系统中,     

LPCVDLTO的工艺研究

本文以热力学与统计物理的理论为基础，对ＬＰＣＶＤＬＴＯ（低温氧化）工艺出现的问题进行了数理分析，从而确定了分子热运动的平均自由程与流量比及沉积压力之间的关系，并用其指导实际工作，从根本上解决反应气流不稳定这一技术难题。     

2003:工艺信息化元年

工艺信息化是企业信息化建设成功的前提,它既是产品质量、交货周期和控制成本的关键,也是其他部门信息化(ERP等)的数据枢纽和制造业信息化的基础。工艺信息化的基础技术——CAPP,经过30余年的研究和应用,在企业的应用效果一直不理想(甚至是全部失败),给企业留下了很不好的印象。直到最近三四年,经过国内几家CAPP系统专业供应商的共同努力,CAPP技术和应用得到了空前的发展,特别是在企业信息化思想的指导下,逐渐提出了“面向企业信息化,从工艺设计、工艺管理、工艺数据挖掘利用、工艺数据集成应用、面向特定专业的智能化应用等多个方面…     

2003:工艺信息化元年

工艺信息化是企业信息化建设成功的前提,它既是产品质量、交货周期和控制成本的关键,也是其他部门信息化(ERP等)的数据枢纽和制造业信息化的基础.……     

CAPP与民航座椅工艺信息化

一、背景中国航空救生研究所是目前国内唯一从事军机弹射救生座椅和民航客机座椅研制、生产的专业化研究所,其生产的民航客机座椅是高度个性化的高科技产品,被广泛地用于美国“波音”、“麦道”、欧洲的“空中客车”、俄罗斯的“图154”和国内的“运7”、“运8”、“新舟60”等     

车身覆盖件模具数控加工工艺方案的确定

汽车覆盖件模具是汽车生产中非常重要的工艺装备，其型面多为立体曲面，并且结构复杂．品种繁多．因此在现代模具生产中多采用数控加工的方法。在采用数控加工时，确定怎样的加工方法，也就是如何进行数控加工，对整套模具均有较大影响，甚至由于无法确定合适的加工方法．而不能利用现有机床进行数控加工，或由于方法选择不当，造成往返工作与加工误差的增多。因此，合理地确定数控加工方法，是制订数控加工工艺的基础。本结合一汽模具中心近年来制造各类汽车覆盖件模具中的一些典型结构，论述了在模具数控加工中如何合理地确定数控加工方法：     

Spatio-temporal distribution of rice phenology and cropping systems in the Mekong Delta with special reference to the seasonal water flow of the Mekong and Bassac rivers

Multi-temporal Moderate Resolution Imaging Spectroradiometer (MODIS) data was used to estimate the spatial distribution of heading date and rice-cropping system employed in the Mekong Delta relative to seasonal changes in water resources in 2002 and 2003. We improved a Wavelet-based Filter for determining Crop Phenology (WFCP) and developed a Wavelet-based Filter for evaluating the spatial distribution of Cropping Systems (WFCS) to the interpretation of MODIS time-series data to determine the spatial distribution of rice phenology and various rice-cropping systems from the seasonal Enhanced Vegetation Index (EVI) data. The findings correspond well the physical characteristics of the cropping system in the Mekong Delta, which have changed over time in response to localized and seasonal changes in water resources. One such example is the double-irrigated rice-cropping system commonly employed in the upper Mekong Delta in the dry season to avoid damage due to the subsequent floods. The shortage of suitable irrigation water and intrusion of saline water in the coastal regions during the dry season has constrained the practice dry-season cropping and has meant that the double- and single-rainfed rice-cropping systems are employed in the rainy season. A triple-irrigated rice-cropping system is used in the central part of the Mekong Delta which is located midway between the flood-prone and salinity intrusion areas. Analysis of annual changes in the rice cropping systems between 2002 and 2003 showed that the triple-cropped rice expanded to the flood- and salinity-intrusion areas. This expansion indicates that the implementation of measures to limit the extent of flooding and salinity intrusion by improved farming technologies and improvements in land management. The heading dates in the upper Mekong Delta in 2003 were earlier than in 2002 by approximately 20 to 30 days. The reasons for this would be due to decreased flood runoff in 2002 compared to 2001, and implementation of government policies regarding early sowing of dry-season crops. Subsequent analysis of the MODIS data confirmed that the spatial distribution of rice-cropping systems was closely related to seasonal changes in river runoff regime in the Mekong Delta.     

关联规则挖掘技术研究进展*

为帮助人们深入研究关联规则挖掘技术,总结了关联规则的分类方法、评价方法以及相关技术的最新进展,特别是对关联规则的主要算法进行了详细的介绍,并探讨未来的发展方向。该研究比较系统全面,对将来进一步深入分析关联规则挖掘技术具有指导意义。     

Ecosystem functioning of protected and altered Mediterranean environments: A remote sensing classification in Doñana, Spain

Spatial heterogeneity in ecosystem functioning is a key component of ecological variability requiring special attention in the context of global change. A large history of human use has produced high physiognomic heterogeneity in Mediterranean ecosystems. However, the consequences for ecosystem functioning remain insufficiently understood. We analyzed spectral indicators of matter and energy fluxes in the land surface to classify the functional ecosystem heterogeneity in a Mediterranean region covering different management histories and protection types. We specifically analyzed the spatial variability in seasonal and annual patterns in the Normalized Difference Vegetation Index (NDVI), surface temperature (T_s) and albedo from five Landsat ETM images. Then we classified numerically this variability into ecosystem functional types (EFTs) and explored their seasonal dynamics in terms of photosynthetic radiation absorption and evapotranspiration. We identified eight main EFTs with ecologically relevant differences including contrasting dynamics in fPAR seasonality, great variation in incoming radiation reflection and differing evapotranspiration rates, particularly during the water-limitation period. Functional variability in natural vegetation mostly consisted in dissimilar annual rates of NDVI and albedo, whereas differences in seasonality were more evident in transformed areas. Similarly, the spatial distribution of EFTs was partly associated to protection, with two EFTs exclusive of protected areas and comparatively higher functional diversity in humanized areas. Landform effects on water availability in protected areas and human activities under different ecological settings were seemingly responsible for the large functional diversity of the region. We advocate for the explicit incorporation of multifunctional ecosystem heterogeneity in ecosystem management and monitoring designs.     

生物组织光声成像技术综述

光声成像是一种低功率、非电离的成像方式,既具有声学方法对深层组织成像分辨率高的优点,又具有光学方法在功能成像、分子成像方面具有高对比度的优势。本文回顾了近年来,光声成像技术在生物医学领域的研究进展,介绍了光声成像的基本成像原理。以此为基础,本文介绍了光声成像的两种主要成像方案：光声断层成像和光声显微镜,并且讨论了光声成像在获取生物组织化学成分信息和微结构信息方面的优越性;最后,本文对光声成像技术的优点和应用前景进行了总结。     

利用MODIS EVI时间序列数据分析福建省植被变化(2000~2017年)

以全国森林覆盖率最高的福建省为研究对象,利用2000~2017年夏季的MODIS EVI植被指数数据和气象与非气象因子进行协同分析,以揭示近17年福建植被的时空变化及其影响因子。结果表明:研究期内福建的EVI均值整体上升,从2000年的0.454上升至2017年的0.505,17 a间上升了11.2%,表明福建省的植被整体处于变好的状态,且在中部和西南部的变化最明显。相关分析表明,在研究期内,气象因子(气温和降水)对EVI变化的影响不显著,植被的变好主要为非气象因子的作用。EVI的提高主要得益于2003年福建省建设生态省后森林覆盖率的提高,并和2012年开始的水土流失治理有明显关系,这说明人类活动的积极作用对福建植被的变好起到了关键的作用。     

Desktop publishing in education

Abstract The term 'desktop publishing' has received much media coverage in recent months in both the commercial and educational press. School-based 'desktop publishing' packages are at the moment poor imitations of full-specification systems. This paper discusses the state of desktop publishing in education today and demonstrates the weaknesses of the systems available for use in the classroom. The skills required for desktop publishing are interrelated in a complex way and cannot be presented in a hierarchical fashion. A model of the functional processes involved is suggested in the paper and analysed in terms of the skills required.     

The influence of IT: perspectives from five Australian schools

Abstract Information and Communication Technologies (ICT) are now widespread in Australian schools but with variation in how, where, when and how much they are used. Computers may be located in a computer laboratory, distributed throughout the school, or students may use their own laptop computers. IT may be a subject in its own right or ICT may be used across all areas of the curriculum. It is how ICT is used in the school setting that is important in providing students with the skills to be participate in a 'knowledge society'. This paper examines the ways in which information and communication technologies influence teaching and learning in five Australian schools. Data were gathered through observation, interviews and document analysis in schools operating at the elementary and secondary grades in relatively technology rich environments. Each of the schools participated in the Australian component of the Second Information Technology in Education Study – Module 2 (SITES-M2) of innovative pedagogical practices. Several of the studies were of specific projects where ICT was the key enabler of the learning programme. Others focused on an entire school's approach to ICT as an agent for changed approaches to learning.     

北半球及典型区雪深时空分布与变化特征

基于欧空局的GlobSnow雪水当量数据集和国家青藏高原科学数据中心的北半球长时间序列雪深数据集NHSD研究了北半球及9个典型区的雪深时空分布与变化特征。结果表明：北半球1988~2018年平均雪深总体呈显著下降趋势（p<0.01）,年际变化幅度为-0.55 cm·（10 a）^-1。在高纬度地区,加拿大北部和阿拉斯加年平均雪深下降明显（p<0.01）,下降速率分别为3.48 cm·（10 a）^-1和3 cm·（10 a）^-1,两地区月平均雪深在冬季显著下降。西西伯利亚平原和东欧平原年平均雪深呈下降趋势,其中东欧平原雪深下降较为明显（p<0.01）,变化速率为-2.3 cm·（10 a）^-1,两地区的月平均雪深在春季显著下降,其中5月份最为明显。东西伯利亚山地的雪深年际变化呈增加趋势,除堪察加半岛外,其月平均雪深在冬季呈显著增加趋势。对于高山区,阿尔卑斯山脉和落基山脉的年平均雪深呈缓慢增长趋势,而青藏高原地区雪深呈缓慢下降趋势。阿尔卑斯山脉的月平均雪深在冬季呈显著增加趋势,5月份显著减小。落基山脉和青藏高原雪深变化呈现出空间异质性：在整个研究时段,落基山脉北部月平均雪深呈下降趋势,中部和南部呈上升趋势;青藏高原的北部边缘山脉雪深呈显著上升趋势,中部大多数地区呈下降趋势。喜马拉雅山脉的北坡雪深增加,南坡雪深减小,但其变化率绝对值小于0.5 cm·a^-1。东南部雪深较大的念青唐古拉山脉冬季雪深呈显著下降趋势。对9个典型区雪深的年内分析（2001~2010年平均值）结果显示：高山区雪深峰值远低于高纬度地区雪深峰值。除青藏高原外,高山区的积雪融化起始日期明显早于高纬度地区。     

Adaptive solutions to the mutual exclusion problem

Summary Algorithms for mutual exclusion that adapt to the current degree of contention are developed. Afilter and a leader election algorithm form the basic building blocks. The algorithms achieve system response times that are independent of the total number of processes and governed instead by the current degree of contention. The final algorithm achieves a constant amortized system response time. Manhoi Choy was born in 1967 in Hong Kong. He received his B.Sc. in Electrical and Electronic Engineerings from the University of Hong Kong in 1989, and his M.Sc. in Computer Science from the University of California at Santa Barbara in 1991. Currently, he is working on his Ph.D. in Computer Science at the University of California at Santa Barbara. His research interests are in the areas of parallel and distributed systems, and distributed algorithms. Ambuj K. Singh is an Assistant Professor in the Department of Computer Science at the University of California, Santa Barbara. He received a Ph.D. in Computer Science from the University of Texas at Austin in 1989, an M.S. in Computer Science from Iowa State University in 1984, and a B.Tech. from the Indian Institute of Technology at Kharagpur in 1982. His research interests are in the areas of adaptive resource allocation, concurrent program development, and distributed shared memory.A preliminary version of the paper appeared in the 12th Annual ACM Symposium on Principles of Distributed ComputingWork supported in part by NSF grants CCR-9008628 and CCR-9223094     

Stability of nonlinear hybrid dynamical systems with time delay via sum of squares decomposition

Considering an infinite number of eigenvalues for time delay systems, it is difficult to determine their stability. We have developed a new approach for the stability test of time delay nonlinear hybrid systems. Construction of Lyapunov functions for hybrid systems is generally a difficult task, but once these functions are found, stability’s analysis of the system is straight-forward. In this paper both delay-independent and delay-dependent stability tests are proposed, based on the construction of appropriate Lyapunov-Krasovskii functionals. The methodology is based on the sum of squares decomposition of multivariate polynomials and the algorithmic construction is achieved through the use of semidefinite programming. The reduction techniques provide numerical solution of large-scale instances; otherwise they will be computationally infeasible to solve. The introduced method can be used for hybrid systems with linear or nonlinear vector fields. Finally simulation results show the correctness and validity of the designed method. Recommended by Editorial Board member Young Soo Suh under the direction of Editor Jae Weon Choi. The authors wish to express their thanks to Dr. A. Papachristodoulou and Dr. M. Peet for their helpful comments and suggestions. Mohammad Ali Badamchizadeh was born in Tabriz, Iran, in December 1975. He received the B.S. degree in Electrical Engineering from University of Tabriz in 1998 and the M.Sc. degree in Control Engineering from University of Tabriz in 2001. He received the Ph.D. degree in Control Engineering from University of Tabriz in 2007. He is now an Assistant Professor in the Faculty of Electrical and Computer Engineering at University of Tabriz. His research interests include Hybrid dynamical systems, Stability of systems, Time delay systems, Robot path planning. Sohrab Khanmohammadi received the B.S. degree in Industrial Engineering from Sharif University, Iran in 1977 and the M.Sc. degree in Automatic from University Paul Sabatie, France in 1980 and the Ph.D. degree in Automatic from National University, ENSAE, France in 1983. He is now a Professor of Electrical Engineering at University of Tabriz. His research interests are Fuzzy control, Artificial Intelligence applications in control and simulation on industrial systems and human behavior. Gasem Alizadeh was born in Tabriz, Iran in 1967. He received the B.S. degree in Electrical Engineering from Sharif University, Iran in 1990 and the M.Sc. degree from Khajeh Nasir Toosi University, Iran in 1993 and the Ph.D. degree in Electrical Engineering from Tarbiat Modarres University, Iran in 1998. From 1998, he is a Member of University of Tabriz in Iran. His research interests are robust and optimal control, guidance, navigation and adaptive control. Ali Aghagolzadeh was born in Babol, Iran. He received the B.S. degree in Electrical Engineering in 1985 from University of Tabriz, Tabriz, Iran, and the M.Sc. degree in Electrical Engineering in 1988 from the Illinois Institute of Technology, Chicago, IL. He also attended the School of Electrical Engineering at Purdue University in August 1998 where he was also employed as a part-time research assistant and received the Ph.D. degree in 1991. He is currently an Associate Professor of Electrical Engineering at University of Tabriz, Tabriz, Iran. His research interests include digital signal and image processing, image coding and communication, computer vision, and image analysis.