国产化辽宁省防汛抗旱指挥平台建设

为满足国家政务系统安全、可靠的要求,从服务器、操作系统、数据库等国产自主可控产品的类型,功能特点,性能与安全性等方面进行综合比较,并进行国产化适配,最终组成一套适合工作实际的国产化产品组合,搭建基于国产化自主可控产品的辽宁省防汛抗旱指挥平台。该平台遵循水利部数字孪生流域技术框架,结合辽宁省防汛抗旱业务需求,形成“四横两纵”技术框架,集成实时和基础信息展示查询、信息监测、水利一张图、防洪“四预”等功能模块,实现流域防洪业务智能化管理及场景数字化、模拟精准化、决策智慧化。研究成果可为今后建设国产化水利业务系统提供示范。     

基于自适应滑模层极值搜索的光伏发电最大功率跟踪方法

保证光伏阵列快速到达最大功率点并且能稳定运行,一直以来是光伏发电研究领域关注的重要问题之一。为此,文中提出了基于参数自适应调整滑模层极值搜索控制的光伏发电系统最大功率跟踪新方法。首先证明了基于滑模极值搜索的光伏发电系统最大功率跟踪控制策略的稳定性;然后提出采用具有更低控制频率及更低控制噪声的滑模层函数代替简单的开关函数。在此基础上,进一步提出了控制参数的自适应调整方法,使得控制系统在具有较好的控制品质的同时,避免了繁琐的人为参数调整。算例证明了所提方法的有效性。     

Water‐saving approaches for improving wheat production

The greatest fear of global climate change is drought. World‐wide, 61% of countries receive rainfall of less than 500 mm annually; domestication of wheat first occurred in such a semiarid region of southwestern Asia, and it seems that wheat foods originally came from dryland gardens. Wheat plants respond to drought through morphological, physiological and metabolic modifications in all plant parts. At the cellular level, plant responses to water deficit may result from cell damage, whereas other responses may correspond to adaptive processes. Although a large number of drought‐induced genes have been identified in a wide range of wheat varieties, a molecular basis for wheat plant tolerance to water stress remains far from being completely understood. The rapid translocation of abscissic acid (ABA) in shoots via xylem flux, and the increase of ABA concentration in wheat plant parts correlate with the major physiological changes that occur during plant response to drought. It is widely accepted that ABA mediates general adaptive responses to drought. For a relatively determinate target stress environment, and with stable genotype × environment interaction, the probability for achieving progress is high. This approach will be possible only after we learn more about the physiology and genetics of wheat plant responses to water stress and their interactions. The difficulties encountered by molecular biologists in attempting to improve crop drought tolerance are due to our ignorance in agronomy and crop physiology and not to lack of knowledge or technical expertise in molecular biology. Copyright © 2005 Society of Chemical Industry     

Influence of organic acid concentration on survival of Listeria monocytogenes and Escherichia coli 0157:H7 in beef carcass wash water and on model equipment surfaces

Acid-adapted cultures of Escherichia coli O157:H7 and Listeria monocytogenes were inoculated in meat decontamination spray-washing runoff fluids in order to evaluate their survival and potential to form biofilms on stainless steel coupons. The cultures (10⁷ cfu ml⁻¹) and stainless steel coupons were exposed to mixtures of water and organic acid washings (composites of each of 2% acetic acid or lactic acid washings with water washings from meat decontamination in proportions of 1/9, 1/49, 1/99 [vol/vol]) or to water washings for up to 14 days at 15°C. E. coli O157:H7 formed biofilms and remained detectable (1.3 log cfu cm⁻²) on stainless steel for up to 4 d in the 1/9 dilution (pH 3.17–3.77) of the organic acid washings, and persisted throughout storage (14 d) in the 1/49 (pH 3.96–4.33) and 1/99 (pH 4.34–6.86) dilution of the organic acid washings. L. monocytogenes populations were unable to form detectable (<1.3 log cfu cm⁻²) biofilms in the 1/9 and 1/49 dilutions of both organic acid washings for up to 14 d; however, by day-14 in the 1/99 dilution of the washings, the pathogen was able to attach at detectable levels (2.7 to 3.4 logs). The pH effects of lower concentrations (1/49 or 1/99) of acidic washings decreased over time due to the formation of amine compounds produced by the natural meat flora, allowing resuscitation of the acid-stressed pathogen survivors. The resuscitation of acid-stressed pathogens may potentially enhance their survival and prevalence in biofilms and thus more attention should be focused on avoiding or minimizing the collection of decontamination runoff fluids on food contact equipment surfaces.     

Comparison of acids on the induction of an Acid Tolerance Response in Salmonellatyphimurium, consequences for food safety

Salmonellatyphimurium inactivation at pH 3.0 in Brain Heart Infusion (BHI) and Meat Extract (ME) was studied using stationary-phase cells grown in non-acidified BHI (pH 7.4) and ME (pH 6.6) and acidified BHI and ME at pH values of 6.4, 5.4 and 4.5 with acetic, ascorbic, citric, lactic, malic and hydrochloric acids. Cells grown in buffered BHI (pH 7.0) were used as non-acid adapted control cells.     

浅谈建筑的地域性气候适应——以赵家堡为例探究建筑的气候特征

建筑是以人为本,建筑也同样是与大自然合而为一。建筑适应当地的气候,表现出各式各样的建筑形式,也即"形式追随气候"。本文以赵家堡传统村落为例探究建筑的地域性气候适应,研究建筑的气候特征,从而更好的指导建筑设计。     

The Tiny Companion Matters: The Important Role of Protons in Active Transports in Plants

In plants, the translocation of molecules, such as ions, metabolites, and hormones, between different subcellular compartments or different cells is achieved by transmembrane transporters, which play important roles in growth, development, and adaptation to the environment. To facilitate transport in a specific direction, active transporters that can translocate their substrates against the concentration gradient are needed. Examples of major active transporters in plants include ATP-binding cassette (ABC) transporters, multidrug and toxic compound extrusion (MATE) transporters, monosaccharide transporters (MSTs), sucrose transporters (SUTs), and amino acid transporters. Transport via ABC transporters is driven by ATP. The electrochemical gradient across the membrane energizes these secondary transporters. The pH in each cell and subcellular compartment is tightly regulated and yet highly dynamic, especially when under stress. Here, the effects of cellular and subcellular pH on the activities of ABC transporters, MATE transporters, MSTs, SUTs, and amino acid transporters will be discussed to enhance our understanding of their mechanics. The relation of the altered transporter activities to various biological processes of plants will also be addressed. Although most molecular transport research has focused on the substrate, the role of protons, the tiny counterparts of the substrate, should also not be ignored.     

局部一致性主动学习的源域无关开集域自适应

无监督域自适应在解决训练集(源域)和测试集(目标域)分布不一致的问题上已经取得了一定的成功.在面向低能耗场景和开放动态任务环境时,在资源约束和开放类别出现的情况下,现有的无监督域自适应方法面临着严峻的挑战.源域无关开集域自适应(SF-ODA)旨在将源域模型中的知识迁移到开放类出现的无标签目标域,从而在无源域数据资源的限制下辨别公共类和检测开放类.现有的源域无关开集域自适应的方法聚焦于设计准确检测开放类别的源域模型或增改模型的结构.但是,这些方法不仅需要额外的存储空间和训练开销,而且在严格的隐私保护场景下难以实现.提出了一个更加实际的场景:主动学习的源域无关开集域自适应(ASF-ODA),目标是基于一个普通训练的源域模型和少量专家标注的有价值的目标域样本来实现鲁棒的迁移.为了达成此目标,提出了局部一致性主动学习(LCAL)算法.首先,利用目标域中局部特征标签一致的特点,LCAL设计了一种新的主动选择方法:局部多样性选择,来挑选更有价值的阈值模糊样本来促进开放类和公共类分离.接着,LCAL基于信息熵初步筛选出潜在的公共类集合和开放类集合,并利用第一步得到的主动标注样本对这两个集合进行匹配纠...