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Knowledge Should Be Owned by Quality Practitioners in the IT Age 预览
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作者 Kuan Sheng-Pin Perng Horng-Linn 《交通与运输工程:英文版》 2019年第1期38-50,共13页
Industry 4.0 is a collective term including a number of automation,data exchange and manufacturing.It will create many kinds of innovative business model via customized design and marketing.From the supplier chain:pur... Industry 4.0 is a collective term including a number of automation,data exchange and manufacturing.It will create many kinds of innovative business model via customized design and marketing.From the supplier chain:purchasing,production controlling,incoming,production and shipping to the demand chain:ordering,logistics delivery,retail,and maintain service,it can integrate the all processes to be a value chain through computation,communication,controlling,collaboration and real time response.The quality requirements of all processes of the value chain would be much more transparent.As the demand chain,product and service will be required more accurate,speedy,reliable,safety,ecological,and environmental.As the supplier chain,the product and service will be required more easily to design,manufacture,change,transport,maintain,recycle and trace.Under the development of Industry 4.0,the entire value chain system will generate a large amount of data,including data related customers,data from suppliers and production,analysis of these data must apply SPC(statistical process control)and statistical techniques.Therefore,people in the value chain should strengthen the traditional quality management knowledge and skills,but also understand the development and application of ICT(information communication technology).The following are the relevant ICT knowledge and technologies of the sensing layer,the network layer,the application layer and value integration layer in the entire value chain system:(1)Sensing layer:SCADA(supervisory control and data acquisition),PLC(programmable logic controller),sensor equipments,Bar Code ID,RFID(radio frequency identification);(2)Network layer:basic network knowledge,basic knowledge of cloud computing;(3)Application layer:DBMS(database management system),MES(manufacture execution system),ERP(enterprise resource planning),PLM(product lifecycle management),CRM(customer relationship management),SCM(supplier chain management);(4)Value integration layer:hardware and software system integration engi 展开更多
关键词 Industry 4.0 SUPPLIER CHAIN DEMAND CHAIN value CHAIN
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卡链工况下综采刮板输送机链轮的动力学特性研究 预览
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作者 仝晓军 《机械管理开发》 2019年第8期125-126,共2页
针对刮板输送机的链轮与链条在啮合时出现卡链现象,导致出现链轮断裂、脱齿等异常情况,根据刮板输送机链传动系统的工作特性,通过建立刮板输送机链轮传动系统的等效动力学模型,对在输送机运行过程中链轮和链环的啮合动力学进行研究,分... 针对刮板输送机的链轮与链条在啮合时出现卡链现象,导致出现链轮断裂、脱齿等异常情况,根据刮板输送机链传动系统的工作特性,通过建立刮板输送机链轮传动系统的等效动力学模型,对在输送机运行过程中链轮和链环的啮合动力学进行研究,分析在卡链工况下链轮的动力学特性,为优化链轮结构、提升链传动系统工作的可靠性和稳定性提供理论基础。 展开更多
关键词 刮板输送机 卡链 链轮 动力学特性
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国内加油站连锁便利店供应链变革方向 预览
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作者 袁海东 《当代石油石化》 CAS 2019年第3期32-38,共7页
通过深入研究国内加油站连锁便利店供应链现状,并与主流的社会零售企业全方位比对,发现该类企业在采购水平、仓储布局、配送效率、信息化建设及人才、设备投入方面存在的差距。在此基础上,以问题和业务需求为导向,立足加油站连锁便利店... 通过深入研究国内加油站连锁便利店供应链现状,并与主流的社会零售企业全方位比对,发现该类企业在采购水平、仓储布局、配送效率、信息化建设及人才、设备投入方面存在的差距。在此基础上,以问题和业务需求为导向,立足加油站连锁便利店人、货、场的特点,对应提出优化措施,有效提高供应链执行效率、降低运营成本,逐步构建具有加油站连锁便利店特色的竞争优势,提升其在零售行业的市场竞争力和渠道影响力。 展开更多
关键词 加油站 连锁 便利店 供应链 变革
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刮板输送机链条张紧方式研究 预览
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作者 田瑞鑫 《石化技术》 CAS 2019年第8期79-79,86,共2页
本文设计了一种新型刮板机自动张紧装置。该装置通过监测刮板机链条张紧程度,并通过PLC控制器控制油缸伸缩量,保证链条始终处于设定的压力范围内,实现对刮板机链条自动张紧。
关键词 刮板输送机 链条 张紧 断链
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一种极低IO带宽需求的大维度矩阵链式矩阵乘法器设计 预览
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作者 宋宇鲲 郑强强 +1 位作者 王泽中 张多利 《电子技术应用》 2019年第9期32-38,共7页
大维度矩阵乘法常采用子矩阵分块法实现,子矩阵的最大规模决定了整个矩阵乘法执行速度。针对经典脉动结构直接处理的矩阵规模受IO带宽限制严重的问题,提出了一种极低IO带宽需求的大维度矩阵链式乘法器结构,并完成了硬件设计实现与性能... 大维度矩阵乘法常采用子矩阵分块法实现,子矩阵的最大规模决定了整个矩阵乘法执行速度。针对经典脉动结构直接处理的矩阵规模受IO带宽限制严重的问题,提出了一种极低IO带宽需求的大维度矩阵链式乘法器结构,并完成了硬件设计实现与性能验证工作。主要工作如下:(1)优化了矩阵乘法的数据组织,实现输入矩阵规模与IO带宽无关,能够最大限度地利用器件内部逻辑和存储资源;(2)根据优化后数据组织形式设计了链式乘法器硬件,实现源数据计算和传输重叠操作;(3)增强乘法器对矩阵规模的适应性,所设计的链式乘法器可实时配置为多条独立链,并行多组运算;(4)在Xilinx C7V2000T FPGA芯片上完成不同种规模的链式乘法器硬件实现和性能测试工作,在该芯片上本文提出的链式乘法器最多支持800个运算单元,是经典脉动结构规模的8倍;在相同运算器个数下,本文提出的链式乘法器只使用经典脉动结构运算1/8的IO带宽即获得相等性能。 展开更多
关键词 矩阵乘 脉动 链式 IO带宽 FPGA
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Pathways of Influence of the Northern Hemisphere Mid–high Latitudes on East Asian Climate:A Review 预览
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作者 Jianping LI Fei ZHENG +2 位作者 Cheng SUN Juan FENG Jing WANG 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第9期902-921,共20页
This paper reviews recent progress made by Chinese scientists on the pathways of influence of the Northern Hemisphere mid-high latitudes on East Asian climate within the framework of a“coupled oceanic-atmospheric(lan... This paper reviews recent progress made by Chinese scientists on the pathways of influence of the Northern Hemisphere mid-high latitudes on East Asian climate within the framework of a“coupled oceanic-atmospheric(land-atmospheric or seaice-atmospheric)bridge”and“chain coupled bridge”.Four major categories of pathways are concentrated upon,as follows:Pathway A—from North Atlantic to East Asia;Pathway B—from the North Pacific to East Asia;Pathway C—from the Arctic to East Asia;and Pathway D—the synergistic effects of the mid-high latitudes and tropics.In addition,definitions of the terms“combined effect”,“synergistic effect”and“antagonistic effect”of two or more factors of influence or processes and their criteria are introduced,so as to objectively investigate those effects in future research. 展开更多
关键词 East Asian climate Northern HEMISPHERE mid-high LATITUDES COUPLED oceanic-land-sea-ice-atmospheric BRIDGE chain COUPLED BRIDGE pathway synergistic effect
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Internal incentives and operations strategies for the watersaving supply chain with cap-and-trade regulation
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作者 Zhisong CHEN Li FANG Huimin WANG 《工程管理前沿:英文版》 2019年第1期87-101,共15页
Faced with the rapid development of modem industries of agriculture, manufacturing, and services, water resources are becoming increasingly scarce. Industries with high water consumption are generally regulated by the... Faced with the rapid development of modem industries of agriculture, manufacturing, and services, water resources are becoming increasingly scarce. Industries with high water consumption are generally regulated by the government's water cap-and-trade (CAT) regulation to solve the contradiction between the limited water supply and the rapid growing water demand. Supply chain equilibrium and coordination models under the benchmark scenario without water saving and CAT regulation, watersaving supply chain equilibrium and coordination models under the scenario without/with CAT regulation are developed, analyzed and compared. The corresponding numerical and sensitivity analyses for all models are conducted and compared, and the managerial insights and policy recommendations are summarized in this article. The results indicate that (1) Conducting water saving could improve effectively the operational performance of the water-saving supply chain under the scenario without/with CAT regulation.(2) The coordination strategy based on the revenue sharing contract could efficiently coordinate the water-saving supply chain, enhance water consumption reduction rate, and improve the operational performance of the water-saving supply chain.(3) The implementation of CAT regulation enhances effectively water-consumptio reduction in the water-saving supply chain and improves the operational performance of water-saving supply chain.(4) Simultaneous implementation of CAT regulation by the government and adopting coordination strategy by the water-saving supply chain would be superior to any other scenarios/strategies.(5) A suitable water cap based on the industrial average water consumption and historical water consumption data are beneficial for constructing reasonable and effective incentive mechanism.(6) A higher marginal trade price could induce more reduction in water consumption and create better operational performance for the manufacturer and water-saving supply chain, both under the equilibrium and coordination strategies. 展开更多
关键词 WATER-SAVING supply chain equilibrium coordination INTERNAL INCENTIVE cap and trade REGULATION
A Novel Multi-Points Laser Monitoring of Building Settlement and Its Risk Evaluation
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作者 CHAI Caiping WU Zejian +5 位作者 WANG Huifeng GUAN Limin HUANG He MU Kenan CUI Wenfen HAO Ting 《武汉大学学报:自然科学英文版》 CAS CSCD 2019年第5期442-454,共13页
Aiming at the defects of routine settlement measurement methods, such as complicated procedures, time-consuming and labor-intensive, high cost and low measurement accuracy, based on the analysis of existing engineerin... Aiming at the defects of routine settlement measurement methods, such as complicated procedures, time-consuming and labor-intensive, high cost and low measurement accuracy, based on the analysis of existing engineering measurement technical requirements and specifications, a multi-point high precision and high efficiency based on laser reference is proposed. The automatic building settlement real-time monitoring system program gives the principle and system model of single-point settlement observation. The model of multi-point scanning settlement monitoring system and the model of multi-point network settlement monitoring system are designed, and their advantages and disadvantages are analyzed. We focus on the networked multi-point settlement monitoring system for network cumulative error analysis, and propose related evaluation and correction methods. The hardware schematic and software block diagram of the laser reference measurement and measurement system of the single point settlement acquisition system are given. Finally, the risk of subsidence state is quantitatively evaluated based on multi-point settlement monitoring data. The measurement error of this method is less than 300 μm, which can realize the monitoring and evaluation of the overall settlement. 展开更多
关键词 measurement technology LASER REFERENCE SETTLEMENT CHAIN linear ARRAY Charge-Coupled Device(CCD)
Periodic Solution and Ergodic Stationary Distribution of Stochastic SIRI Epidemic Systems with Nonlinear Perturbations
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作者 ZHANG Weiwei MENG Xinzhu DONG Yulin 《系统科学与复杂性学报:英文版》 SCIE EI CSCD 2019年第4期1104-1124,共21页
This paper formulates two stochastic nonautonomous SIRI epidemic systems with nonlinear perturbations.The main aim of this study is to investigate stochastic dynamics of the two SIRI epidemic systems and obtain their ... This paper formulates two stochastic nonautonomous SIRI epidemic systems with nonlinear perturbations.The main aim of this study is to investigate stochastic dynamics of the two SIRI epidemic systems and obtain their thresholds.For the nonautonomous stochastic SIRI epidemic system with white noise,the authors provide analytic results regarding the stochastic boundedness,stochastic permanence and persistence in mean.Moreover,the authors prove that the system has at least one nontrivial positive T-periodic solution by using Lyapunov function and Hasminskii’s theory.For the system with Markov conversion,the authors establish sufficient conditions for positive recurrence and existence of ergodic stationary distribution.In addition,sufficient conditions for the extinction of disease are obtained.Finally,numerical simulations are introduced to illustrate the main results. 展开更多
关键词 Extinction and STOCHASTIC permanence Markov chain periodic solution stationary distribution and ERGODICITY STOCHASTIC SIRI EPIDEMIC model
Laboratory diagnosis of schistosomiasis mansoni: Current status and future trends
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作者 Amira Taman Samar N.El-Beshbishi 《亚太热带医药杂志:英文版》 SCIE CAS 2019年第6期243-249,共7页
Schistosomiasis is a neglected tropical disease that affects about 290 million patients worldwide. Children aged between 5 and 14 years represent 45.8% of the affected patients, in addition, schistosomiasis has been r... Schistosomiasis is a neglected tropical disease that affects about 290 million patients worldwide. Children aged between 5 and 14 years represent 45.8% of the affected patients, in addition, schistosomiasis has been reported in Schistosoma-free areas, mostly because of tourism and immigration from endemic countries. Intestinal schistosomiasis caused by Schistosoma mansoni is mainly diagnosed via direct stool examination for egg detection. Immunological methods are favoured for disease monitoring and preliminary checking for communities in areas with low infection rates, and for patients with light and chronic infections where parasitological tests are negative. PCR-based diagnostic techniques are more sensitive, but expensive. Tegument proteins and miRNAs are promising markers for diagnosis of schistosomiasis. Here we review the diagnostic methods for schistosomiasis mansoni aiming to reach a standardized technique for diagnosis of early infection to help better control of the disease. 展开更多
关键词 SCHISTOSOMA MANSONI ELISA miRNA TEGUMENT POLYMERASE CHAIN REACTION
Regioselective Polymerizations of α-Olefins with an α-Diamine Nickel Catalyst
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作者 Heng Liao Jie Gao +2 位作者 Liu Zhong Hai-Yang Gao Qing Wu 《高分子科学:英文版》 SCIE CAS CSCD 2019年第10期959-965,I0003,共8页
Polymerizations of linear α-olefins(CnH2n, CH2=CH―R, R = Cn-2) catalyzed by early transition metals typically afford amorphous polymers with alkyl chains(Cn-2), while chain-straightening polymerizations of α-olefin... Polymerizations of linear α-olefins(CnH2n, CH2=CH―R, R = Cn-2) catalyzed by early transition metals typically afford amorphous polymers with alkyl chains(Cn-2), while chain-straightening polymerizations of α-olefins with nickel-based catalysts produce semicrystalline polyolefins. Polymerizations of various α-olefins were carried out using an α-diamine nickel catalyst with a significantly distorted chelating ring. The influences of temperature, monomer concentration, and chain length of α-olefins on polyolefin microstructure were examined in detail. The α-diamine nickel catalyst realized highly regioselective 2,1-insertion of α-olefins regardless of reaction temperature and monomer concentration. Increased chain length of α-olefins led to the formation of more linear polyolefin.Semicrystalline polyolefins with high melting temperatures(Tm) were made from α-olefins through highly regioselective 2,1-insertion and precise chain-straightening. 展开更多
关键词 Nickel catalyst Α-OLEFIN POLYMERIZATION Regioselectivity Chain walking
Wholesale Pricing and Evolutionarily Stable Strategy in Duopoly Supply Chains with Social Responsibility
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作者 Caichun Chai Tiaojun Xiao 《系统科学与系统工程学报:英文版》 SCIE EI CSCD 2019年第1期110-125,共16页
This paper analyzes manufacturers’ wholesale price decisions and the evolutionarily stable strategies of the retailers’ marketing behavior in duopoly supply chains, where each chain consists of one manufacturer and ... This paper analyzes manufacturers’ wholesale price decisions and the evolutionarily stable strategies of the retailers’ marketing behavior in duopoly supply chains, where each chain consists of one manufacturer and many retailers. Each retailer chooses one of two marketing strategies: social responsibility or non-social responsibility (i.e., a firm only cares about the benefits of its shareholders). We identify the conditions under which a strategy profile is evolutionarily stable. Furthermore, we investigate the manufacturers’ wholesale prices and find the following:(i) the retailer’s social responsibility decreases the unit wholesale price;(ii) when the degree of the retailer’s social responsibility is medium, the social responsibility of the retailer in a supply chain increases the profit of the retailer’s own manufacturer and decreases the profit of the rival’s manufacturer;otherwise, it decreases the profits of the two manufacturers;and (iii) when each retailer exhibits its social responsibility moderately, a triple-win situation can be achieved. 展开更多
关键词 Evolutionarily stable strategy REPLICATOR dynamics social RESPONSIBILITY supply chain management
Synthesis of Alkyne-functionalized Polymers via Living Anionic Polymerization and Investigation of Features during the Post-“thiol-yne” Click Reaction
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作者 Lin-Can Yang Li Han +5 位作者 Hong-Wei Ma Pi-Bo Liu He-Yu Shen Chao Li Song-Bo Zhang Yang Li 《高分子科学:英文版》 SCIE CAS CSCD 2019年第9期841-850,共10页
"Thiol-yne" click reaction has already been widely applied in synthesis and modification of new polymer structures or novel materials due to its specific features. However, in most studies, only chain-end st... "Thiol-yne" click reaction has already been widely applied in synthesis and modification of new polymer structures or novel materials due to its specific features. However, in most studies, only chain-end strategy was employed when using the di-addition feature of thiol-yne reaction, thus the in-chain di-addition strategy could endow us with a broader space to develop the synthesis of advanced polymers. Therefore, in this paper, the features of in-chain mono and di-addition were investigated when modifying the alkynefunctionalized polymers to prepare grafted polymers via thiol-yne click reaction. The results showed that it is almost impossible to obtain the in-chain di-adducts even under excess feeding of chain-end thiol-functionalized grafts, while only the in-chain mono-adducts could be obtained efficiently. Further researches investigated that the controlled grafting could be encountered when carrying out the thiol-yne click reaction between chain-end alkyne-functionalized polystyrenes and chain-end thiol-functionalized polystyrenes under proper feedings. Therefore, the effect of steric?hindrance might be the primary reason for the alternative grafting via thiol-yne click reaction between in-chain and chain-end alkyne-functionalized polymers. 展开更多
关键词 Alkyne-functionalized polymers In-chain di-addition Thiol-yne CLICK reaction Living ANIONIC polymerization
A User-friendly Living Cationic Polymerization: Degenerative Chaintransfer Polymerization of Vinyl Ethers by Simply Using Mixtures of Weak and Superstrong Protonic Acids
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作者 Mineto Uchiyama Masataka Sakaguchi +1 位作者 Kotaro Satoh Masami Kamigaito 《高分子科学:英文版》 SCIE CAS CSCD 2019年第9期851-857,共7页
Mixtures of a weak protonic acid and a trace amount of superstrong protonic acid were used for the simple control of the cationic polymerization of vinyl ethers via a degenerative chain-transfer mechanism, in which th... Mixtures of a weak protonic acid and a trace amount of superstrong protonic acid were used for the simple control of the cationic polymerization of vinyl ethers via a degenerative chain-transfer mechanism, in which the former acid works as a precursor of the chain transfer agent (CTA) or the dormant species and the latter works as a source of the cationic propagating species. The addition of mixtures of phosphoric acid dibutyl ester ((n=BuO)2PO2H) or 1 -octanethiol (n-C8H17SH) and a trace amount of trifluoromethanesulfonic acid (TfOH) to a solution of isobutyl vinyl ether (IBVE) at -78℃ resulted in polymers with controlled molecular weights, which were basically determined by the feed ratio of IBVE to the weak protonic acid, and narrow molecular weight distributions (Mw/Mn≈ 1.1). These results were almost the same as those obtained using their prepared adducts of IBVE as CT As in the presence of a trace amount of TfOH under similar conditions. Methanesulfonic acid (CH3SO3H), whose adduct of IBVE has not been isolated due to instability, was similarly used in conjunction with trace TfOH to result in controlled molecular weights but slightly broader MWDs (Mw/Mn = 1.2-1.8). These results indicate that the sulfoxonium ion is also an effective intermediate in the cationic DT polymerization in addition to the phosphonium and sulfonium intermediates derived from (n=BuO)2PO2H and C8H17SH, respectively. The simple living cationic polymerization was thus achieved by using a combination of a weak protonic acid and a trace amount of TfOH, which are both easily available, low cost, free from metal, and easy to handle, without need for preparation of the initiator. 展开更多
关键词 Living CATIONIC POLYMERIZATION DEGENERATIVE chain transfer RAFT POLYMERIZATION Metal free VINYL ETHER
Reducing Carbon Emission through Container Shipment Consolidation and Optimization 预览
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作者 Nang Laik Ma Kar Way Tan 《交通与运输工程:英文版》 2019年第3期111-121,共11页
Human’s impact on earth through global warming is more or less an accepted fact.Ocean freight is estimated to contribute 4-5%of global carbon emissions.Many manufacturing companies that transfer ship goods through fu... Human’s impact on earth through global warming is more or less an accepted fact.Ocean freight is estimated to contribute 4-5%of global carbon emissions.Many manufacturing companies that transfer ship goods through full container loads found themselves under-utilizing the containers and resulting in higher carbon footprint per volume shipment.One of the reasons is the choice of non-ideal container sizes for their shipments.In this paper,we first provide an Integer Programming model to minimize the companies’shipping carbon footprints by selecting the ideal container sizes appropriate for their shipment volumes.Secondly,we proposed a strategy to minimize the carbon footprint by consolidating the shipments in the same country from multiple domestic locations at a port of loading by road freight,before the international sea shipment.A mixed-Integer Programming model has been developed to determine if one should ship each shipment separately or have shipments consolidated first before being shipped.Consolidation fills up the containers more efficiently that reduces the overall carbon footprint.Computational results using real-world data indicates a significant 13.4%reduction carbon emission when selecting the optimal combinations of different sizes of containers and an additional 12.1%reduction in carbon emission when shipment consolidation is applied. 展开更多
关键词 Carbon emission data ANALYTICS CONTAINER CONSOLIDATION SUSTAINABILITY optimization ocean FREIGHT supply chain management
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On a Class of Constacyclic Codes of Length 4p^8 over Fpm[u]/〈 u^a 〉
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作者 Hai Q. Dinh Bac T. Nguyen Songsak Sriboonchitta 《代数集刊:英文版》 SCIE CSCD 2019年第2期181-194,共14页
For any odd prime p such that p^m ≡ 3 (mod 4), consider all units Λ of the finite commutative chain ring Ra=Fpm[u]/〈u^a〉=Fp^m+uFp^m+…+u^a1Fp^m that have the form Λ=Λ0 + uΛ1 ++ u^a1 Λa1, where Λ0,Λ1,…,Λa1 ... For any odd prime p such that p^m ≡ 3 (mod 4), consider all units Λ of the finite commutative chain ring Ra=Fpm[u]/〈u^a〉=Fp^m+uFp^m+…+u^a1Fp^m that have the form Λ=Λ0 + uΛ1 ++ u^a1 Λa1, where Λ0,Λ1,…,Λa1 p^m,Λ0 ≠ 0,Λ1 ≠ 0. The class of Λ-constacyclic codes of length 4p^s over a is investigated. If the unit Λ is a square, each Λ-constacyclic code of length 4p^s is expressed as a direct sum of a λ-constacyclic code and a λ-constacyclic code of length 2p^s. In the main case that the unit Λ is not a square, we prove that the polynomial x^4 λ0 can be decomposed as a product of two quadratic irreducible and monic coprime factors, where λ^p^s0=Λ0. From this, the ambient ring Ra[x]/<x^4p^sΛ>is proven to be a principal ideal ring, whose maximal ideals are <x^2 + 2ηx + 2η^2> and <x^2 2ηx + 2η^2>, where λ0 =4η^4. We also give the unique self-dual Type 1 Λ-constacyclic codes of length 4p^s over a. Furthermore, conditions for a Type 1 Λ-constacyclic code to be self-orthogonal and dual-containing are provided. 展开更多
关键词 constacyclic CODES DUAL CODES CHAIN RINGS
Evaluation and comparison of short chain fatty acids composition in gut diseases 预览
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作者 Elena Niccolai Simone Baldi +9 位作者 Federica Ricci Edda Russo Giulia Nannini Marta Menicatti Giovanni Poli Antonio Taddei Gianluca Bartolucci Antonino Salvatore Calabrò Francesco Claudio Stingo Amedeo Amedei 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第36期5543-5558,共16页
BACKGROUND An altered (dysbiosis) and unhealthy status of the gut microbiota is usually responsible for a reduction of short chain fatty acids (SCFAs) concentration. SCFAs obtained from the carbohydrate fermentation p... BACKGROUND An altered (dysbiosis) and unhealthy status of the gut microbiota is usually responsible for a reduction of short chain fatty acids (SCFAs) concentration. SCFAs obtained from the carbohydrate fermentation processes are crucial in maintaining gut homeostasis and their determination in stool samples could provide a faster, reliable and cheaper method to highlight the presence of an intestinal dysbiosis and a biomarker for various gut diseases. We hypothesize that different intestinal diseases, such as celiac disease (CD), adenomatous polyposis (AP) and colorectal cancer (CRC) could display a particular fecal SCFAs’ signature. AIM To compare the fecal SCFAs’ profiles of CD, AP, CRC patients and healthy controls, using the same analytical method. METHODS In this cross-sectional study, we defined and compared the SCFAs’ concentration in fecal samples of 9 AP, 16 CD, 19 CRC patients and 16 healthy controls (HC). The SCFAs’ analysis were performed using a gas-chromatography coupled with mass spectrometry method. Data analysis was carried out using Wilcoxon ranksum test to assess pairwise differences of SCFAs’ profiles, partial least squaresdiscriminate analysis (PLS-DA) to determine the status membership based on distinct SCFAs’ profiles, and Dirichlet regression to determine factors influencing concentration levels of SCFAs. RESULTS We have not observed any difference in the SCFAs’ amount and composition between CD and healthy control. On the contrary, the total amount of SCFAs was significantly lower in CRC patients compared to HC (P = 0.044) and CD (P = 0.005). Moreover, the SCFAs’ percentage composition was different in CRC and AP compared to HC. In detail, HC displayed higher percentage of acetic acid (P value = 1.3 × 10-6) and a lower amount of butyric (P value = 0.02192), isobutyric (P value = 7.4 × 10-5), isovaleric (P value = 0.00012) and valeric (P value = 0.00014) acids compared to CRC patients. AP showed a lower abundance of acetic acid (P value = 0.00062) and higher percentages 展开更多
关键词 Short chain FATTY ACIDS MICROBIOTA Colorectal cancer ADENOMA CELIAC disease
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Chain Inequality Violation with Quantum Weak Measurement Technology
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作者 徐正茂 李宏伟 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第4期393-396,共4页
Bell inequality is an important resource in the quantum information theory, which can be applied to guarantee security of the device independent quantum information protocols. By utilizing the quantum weak measurement... Bell inequality is an important resource in the quantum information theory, which can be applied to guarantee security of the device independent quantum information protocols. By utilizing the quantum weak measurement technology, we propose the Chain inequality violation with three parties, and the analysis result demonstrates that double Chain inequality violation can be observed in the case of Alice and Bob have two different measurement bases.Since the weak measurement model can be assumed to be an eavesdropping model, our analysis model may be applied to analyze security of the device independent quantum information protocols. 展开更多
关键词 CHAIN INEQUALITY WEAK MEASUREMENT
Trend of Digital Transformation Promotion Among Petroleum Enterprises 预览
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作者 Lin Yikai 《中国油气:英文版》 CAS 2019年第1期21-28,共8页
At present, the wave of digitization is sweeping the world while the rapid evolution of the consumer market,cross-border competition between digital enterprises and fierce competition among traditional enterprises are... At present, the wave of digitization is sweeping the world while the rapid evolution of the consumer market,cross-border competition between digital enterprises and fierce competition among traditional enterprises are forcing various industries to speed up their digital transformation. The oil and gas industry has been the practitioner and beneficiary of the application of digital technology for decades;however, it seems to have become the 'laggard' in the new wave of digitization represented by 'CBIMA'(short for cloud computing, big data, the Internet of Things, mobile Internet and artificial intelligence). In the context of low and middling oil prices weakening the profitability of oil and gas companies, increasing competition for alternative energy sources and accelerating energy transformation, there is great potential for promoting the digital transformation of the oil and gas industry. Rebuilding competitiveness through digital transformation is increasingly becoming the consensus in the industry. It would be advisable for Chinese petroleum enterprises to take the initiative to adapt to the trend of digital transformation, formulate clear digital strategies and transformation roadmaps, actively and steadily carry out digital pilot projects, speed up the training of digital professionals and strive to achieve the best transformation results. 展开更多
关键词 Petroleum enterprises Industrial CHAIN Digital strategies Transformation ROADMAP Management mode innovation TALENT training
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Stability of the linear chain structure for 12C in covariant density functional theory on a 3D lattice
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作者 ZhengXue Ren ShuangQuan Zhang +3 位作者 PengWei Zhao Naoyuki Itagaki Joachim AMaruhn Jie Meng 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第11期6-13,共8页
The stability of the linear chain structure of three α clusters for 12C against the bending and fission is investigated in the cranking covariant density functional theory, in which the equation of motion is solved o... The stability of the linear chain structure of three α clusters for 12C against the bending and fission is investigated in the cranking covariant density functional theory, in which the equation of motion is solved on a 3D lattice with the inverse Hamiltonian and the Fourier spectral methods. Starting from a twisted three α initial configuration, it is found that the linear chain structure is stable when the rotational frequency is within the range of ~2.0-~2.5 MeV. Beyond this range, the final states are not stable against fission. By examining the density distributions and the occupation of single-particle levels, however, these fissions are found to arise from the occupation of unphysical continuum with large angular momenta. To properly remove these unphysical continuum, a damping function for the cranking term is introduced. Eventually, the stable linear chain structure could survive up to the rotational frequency ~3.5 MeV, but the fission still occurs when the rotational frequency approaches ~4.0 MeV. 展开更多
关键词 COVARIANT density functional theory cranking model 3D LATTICE space linear chain STRUCTURE alpha-cluster STRUCTURE COLLECTIVE ROTATION 12C
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