人工神经网络在建筑物物理力学参数识别中的应用

基于神经网络的BP算法,建立了识别建筑物物理力学参数的数值方法.在经典的BP算法中,网络中的权值的确定是将权值的计算修正过程描述为网络的训练过程,其中迭代步长由经验选定,常常造成收敛速度慢,并且收敛速度与初始权值的选择有关以及引起振荡等问题.在网络的训练过程中采用改进的BP算法,通过对学习算子的优化搜索,大大提高了网络的收敛速度,解决了BP算法迭代过程中目标函数的震荡问题.数值计算表明,所提出的改进的BP算法进行建筑结构物理力学参数识别的收敛速度和识别精度都得到了提高.     

网络化制造中加工过程仿真的研究

分析了加工过程仿真的工业需求 ,提出加工过程建模和仿真的关键技术问题 ,并实现一种铣削力在网络环境中的仿真     

Three classes of binary linear codes with good parameters

Three classes of linear codes with good parameters are constructed in this paper. The length, dimension and minimum distance for each class of linear codes are also investigated by means of the well-known Kloosterman sums over finite fields. It is interesting to note that the constructed three classes of linear codes possess good parameters and some of them are shown to be optimal.     

1200kt/a乙烯改扩建工程管网改造项目方案探讨

1200kt/a乙烯改扩建工程是大庆石化公司"十一五"发展的重点工程。文中以该工程的工艺及热力管网改造项目为例,从工程概况、材料计划、施工方案编制、过程经营、成本控制、风险防范等方面,探讨了管网改造项目的实施方案。     

反渗透装置处理炼油污水的优化运行

阐述了在土地勘测定界测量中,为了提高工作效率,减少在生产中出现的错误,利用VB2005结合.NET API对AutoCAD进行了二次开发。在土地分类标注文字中,把土地类别和面积分别加入到文字的扩展数据中,然后在面积统计中再提取文字中的扩展数据进行计算并输出至表格,实现了土地利用分类的标注和面积统计的自动化。     

Isolation and identification of high pressure‐resistant bacteria naturally contaminating strawberry pulp

The inactivation of bacteria naturally present in strawberry pulp was investigated after high hydrostatic pressure (HHP) treatment at pressure levels up to 600 MPa at 25 °C for 5 ~ 25 min. Five strains of pressure‐resistant bacteria designated as A, B, C, D and E were isolated and identified. The five strains were gram‐positive, spore‐forming, rods or rod in chains. Growth of the strains was observed at 30 ~ 45 °C, and strain B also grew well at 55 °C. They could produce acid from glucose and were catalase‐positive. Analysis of 16S rRNA gene sequences showed that the five strains belonged to the genus Bacillus. Strain A and D exhibited the greatest 16S rRNA gene sequence similarity of 99% with B. licheniformis and B. firmus, respectively. By combination of phenotypic characteristics and 16S rRNA gene sequences, strain C was B. mycoides and E was B. pumilus. On the basis of physiological and biochemical characteristics, gyrB gene sequences analysis and whole‐cell fatty acids analysis, strain B was B. amyloliquefaciens. Further studies showed that strain B (B. amyloliquefaciens) exhibited the highest pressure resistance, and it was reduced by 4.62‐log after treatment at 600 MPa for 25 min at 25 °C as the most effective observed inactivation.     

面向任务口语理解研究现状综述

口语理解是对话系统重要的功能模块，语义槽填充和意图识别是面向任务口语理解的两个关键子任务。近年来，联合识别方法已经成为解决口语理解中语义槽填充和意图识别任务的主流方法，介绍两个任务由独立建模到联合建模的方法，重点介绍基于深度神经网络的语义槽填充和意图识别联合建模方法，并总结了目前存在的问题以及未来的发展趋势。     

Discovery of Dual ETA/ETB Receptor Antagonists from Traditional Chinese Herbs through in Silico and in Vitro Screening

Endothelin-1 receptors (ETAR and ETBR) act as a pivotal regulator in the biological effects of ET-1 and represent a potential drug target for the treatment of multiple cardiovascular diseases. The purpose of the study is to discover dual ETA/ETB receptor antagonists from traditional Chinese herbs. Ligand- and structure-based virtual screening was performed to screen an in-house database of traditional Chinese herbs, followed by a series of in vitro bioassay evaluation. Aristolochic acid A (AAA) was first confirmed to be a dual ETA/ETB receptor antagonist based intracellular calcium influx assay and impedance-based assay. Dose-response curves showed that AAA can block both ETAR and ETBR with IC₅₀ of 7.91 and 7.40 μM, respectively. Target specificity and cytotoxicity bioassay proved that AAA is a selective dual ETA/ETB receptor antagonist and has no significant cytotoxicity on HEK293/ETAR and HEK293/ETBR cells within 24 h. It is a feasible and effective approach to discover bioactive compounds from traditional Chinese herbs using in silico screening combined with in vitro bioassay evaluation. The structural characteristic of AAA for its activity was especially interpreted, which could provide valuable reference for the further structural modification of AAA.     

Blockchain in global supply chains and cross border trade: a critical synthesis of the state-of-the-art,challenges and opportunities

Blockchain possesses the potential of transforming global supply chain management. Gartner predicts that blockchain could be able to track $2?T of goods and services in their movement across the globe by 2023, and blockchain will be a more than $3 trillion business by 2030. Nowadays, a growing number of blockchain initiatives are disrupting traditional business models in each sector. In this paper, we provide a timely and holistic overview of the state-of-the-art, challenges, gaps and opportunities in global supply chain and trade operations for both the private sector and governmental agencies, by synthesising a wide range of resources from business leaders, global international organisations, leading supply chain consulting firms, research articles, trade magazines and conferences. We then identify collaborative schema and future research directions for industry, government, and academia to jointly work together in ensuring that the full potential of blockchain is unleashed amidst the socioeconomic, geopolitical and technological disruptions that global supply chains and trade are facing.     

Isolation,Purification, and Structural Features of a Polysaccharide from Phellinus linteus and Its Hypoglycemic Effect in Alloxan‐Induced Diabetic Mice

Phellinus linteus is a medicinal mushroom that has been used in Oriental countries for centuries for its antitumor, antioxidant, immunomodulatory, and biological activity on hyperglycemia. A water‐soluble crude polysaccharide was extracted using hot water from P. linteus mycelia grown under submerged culture. An orthogonal experiment was used to optimize the extraction conditions of P. linteus mycelia polysaccharides (PLP). The crude polysaccharide was purified using DEAE Sephadex A‐50 and Sephadex G‐200 chromatography. Fourier transform infrared (FT‐IR) spectroscopy and nuclear magnetic resonance (¹H NMR) spectroscopy were used to investigate the structure of the purified P. linteus polysaccharide (PLP‐I), revealing that it was mainly a branched‐type glycan with both α‐ and β‐linkages and a pyranoid sugar ring conformation. PLP orally administered at 100 mg/kg body weight/d could significantly reduce the blood glucose level by 35.60% in alloxan‐induced diabetic mice. The results of an oral glucose tolerance test (OGTT) revealed that PLP had an effect on glucose disposal after 28 d of treatment. The result revealed that PLP from a submerged culture of P. linteus mycelia possessed potent hypoglycemic properties. The polysaccharide may be useful as a functional food additive and a hypoglycemic agent.