包钢CSP热轧卷板纵裂缺陷分析与控制

为了研究薄板厂CSP产线热轧卷板纵裂缺陷产生原因,对连铸工艺及设备各运行参数进行了调查分析。结果表明,连铸机振动台振动精度差、结晶器铜板结垢是导致热轧卷纵裂缺陷的主要原因。采取调整振动参数、提升振动台对中精度以及控制铜板结垢等措施后,热轧卷板表面纵裂纹缺陷显著降低,纵裂率由最高的1.15%降至0.10%以下。针对CSP铸机,在保证结晶器铜板导热良好的前提下,需严格控制结晶器振动台四连杆机构的关节轴承间隙在0.02 mm以内,振动台台面标高偏差在0.05 mm之内。结晶器振动在水平方向的位移量在0.1 mm以内为宜。     

Integration of wind turbine with heliostat based CSP/CPVT system for hydrogen production and polygeneration: A thermodynamic comparison

In this study, two wind-solar-based polygeneration systems namely CES-1 and CES-2 are developed, modeled, and analyzed thermodynamically. CES-1 hybridizes a heliostat based CSP system with wind turbines while CES-2 integrates heliostat-based CPVT with wind turbines. This study aims to compare the production and thermodynamics performance of two heliostat based concentrated solar power technologies when hybridized with wind turbines. The systems have been modeled to produce, freshwater, hot water, electricity, hydrogen, and cooling with different cycles/subsystems. While the overall objective of the study is to model two polygeneration systems with improved energy and exergy performances, the performances of two solar technologies are compared. The wind turbine system integrated with the comprehensive energy systems will produce 1.14 MW of electricity and it has 72.2% energy and exergy efficiency. Also, based on the same solar energy input, the performance of the heliostat integrated CPVT system (CES-2) is found to be better than that of the CSP based system (CES-1). The polygeneration thermal and exergy efficiencies for the two systems respectively are 48.08% and 31.67% for CES-1; 59.7% and 43.91% for CES-2. Also, the electric power produced by CES-2 is 280 kW higher in comparison to CES-1.     

塔式光热发电无线仪表和无线网络配置研究

本文分析了一种群塔式太阳能光热发电系统的定日镜、吸热蓄热器、汽水管道等系统的基本仪表配置和仪表的主要功能。根据这些仪表配置的特点提出了无线仪表和无线网络的具体配置方案。本文还介绍了每种无线仪表的特点和在群塔式太阳能光热发电系统中的具体应用范围以及各种无线网络设备,如无线多功能节点、各类无线转接模块、手持设备、无线管理平台等的功能以及配置。     

Formalization and analysis of the REST architecture from the process algebra perspective

As one of the most promising architectural styles, REpresentational State Transfer (REST) was proposed to support a scalable and reliable design for large-scale distributed hypermedia systems such as the World Wide Web (WWW). However, the rapid development of RESTful systems brings the misunderstanding and misapplying of the REST architecture. As a consequence, considerable confusions about REST exist and many examples of supposedly RESTful applications violate key REST constraints. Thus, it is of significant importance to give a better and explicit understanding of REST architecture to guide the design and implementations of RESTful systems.In this paper, we give a formalization and analysis of the REST architecture from the perspective of Communicating Sequential Processes (CSP), which is one of the most famous process algebras. In particular, we present a formal model to capture essential features for the REST architecture, where components (together with one connector) of RESTful systems are modeled as CSP processes. Besides, resources are also abstracted as CSP processes. Furthermore, all the REST constraints, including Client–Server, Cacheable, Stateless, Uniform Interface, Layered and Code-On-Demand, are described in our framework and implemented in the model checker Process Analysis Toolkit (PAT) to check whether a system breaks REST constraints or not. It is difficult to ensure that a system is RESTful system, because many unRESTful systems may also contain unRESTful properties besides satisfying the six REST constraints. Thus, a complementary approach is proposed in this paper to check the system from a different perspective; that is, if a system breaks any specification of the REST constraints, then it is not a RESTful system. Finally, to show the feasibility of our approach, we illustrate a case study about an application scenario for environment monitoring. One feature of the proposed framework for the REST architecture is that it not only confines to HyperText Transport Protocol (HTTP) but can also be applied to other REST-compliant protocols, e.g., Constrained Application Protocol (CoAP). Consequently, through the general framework, a better understanding of the REST architecture can be achieved, and moreover, implementations and designs of RESTful systems can benefit from it.     

MY RECOLLECTIONS OF G.2 A.6

Abstract

In this article, we consider an attack on the SIGABA cipher under the assumption that the largest practical keyspace is used. The attack highlights various strengths and weaknesses of SIGABA and provides insight into the inherent level of security provided by the cipher.     

热轧薄板钢焊接区组织与性能分析

采用包钢CSP（Compact Strip Production）薄板坯连铸连轧工艺生产L245钢为原料进行螺旋焊管焊接生产,针对生产中焊缝裂纹问题对焊缝区的形貌、组织进行了观察,并对焊缝进行拉伸性能和X射线检验。分析表明,母材与热影响区的交界处（即偏向热影响区的“过渡区”）是L245焊管力学性能最脆弱处,珠光体的形貌是影响其拉伸性能的关键因素。     

CSP工艺轧制低碳锰钢组织演变模拟

为了选择合适的模型来模拟CSP工艺轧制低碳锰钢的组织变化,首先采用Jonas、Sellars、Saito、Yada等人开发的模型进行模拟,然后采用轧卡试验进行了工业试验验证.轧卡试验和计算结果表明:Jonas模型预测的晶粒尺寸在第一道次较实测值偏小,而在最后几道次较实测值偏大;Yada模型预测值较实测值偏小;Sella...     

CSP热轧CVC工作辊磨损模型优化

通过对钢厂CSP生产线CVC工作辊磨损的实测,得到工作辊的磨损曲线.在此基础上考虑影响轧辊磨损的主要因素,建立了适合CSP生产线的工作辊磨损模型,并且借助MATLAB软件全局优化算法确定了模型中的关键参数.该模型计算结果表明,回归磨损曲线面积与实际磨损曲线面积的相对误差为3.78％,计算值与实测值之间的相关系数0.932 8,可用于轧辊磨损的在线预报.     

Research and Application of Flat Roll Technology in the Downstream Stands for CSP

  CVC mills are generally used in the whole stands of CSP (Compact Strip Product). Their special “s” curve of work roll contour and shifting strategy aimed at controlling strip shape, and the characteristics of continuous casting and rolling production, which make the work roll wear in downstream stands seriously uneven, and easily form abnormal transverse profile at the rolling end. As a result, CVC mill configuration in the downstream stands can not meet the profile and flatness control requirement for schedule free rolling, and bring some difficulties in profile and flatness control for the subsequent cold rolling. Based on the characteristics of the shape control system of CSP production line, and combined with the theory of flat roll technology, a kind of technology solution of using flat roll in the downsteam stands for CSP hot strip mills was proposed. At last, industrial test was carried out in the last stand of Masteel CSP, and good results were obtained.