A Network-Attached Storage System Supporting Guaranteed QoS

We propose a network-attached storage system that can support guaranteed Quality of Service （QoS）, called POPNet Storage. The special policy of date access and disk scheduling is enable users to access files quickly and directly with guaranteed QoS in the POPNet Storage. The POPNet Storage implements a measurement-based admission control algorithm （PSMBAC） to determine whether to admit a new data access request stream and admit as many requests as possible while meeting the QoS guarantees to its clients. The data reconstruction algorithms in the POPNet Storage also put more emphasis on data availability and guaranteed QoS, thus it is designed to complete the data recovery as soon as possible and at the same time provide the guaranteed QoS for high-priority data access. The experiment results show that the POPNet Storage can provide more significant performance, reliability, and guaranteed QoS than conventional storage systems.

HUSTserver:Implementation for Reliable and High-Performance Network Attached Storage System

Network attached storage (NAS) with the properties of improved scalability, simplified management, low cost and balanced price performance, is desirable for high performance storage systems applied to extensive areas. Unfortunately, it also has some disadvantages such as increased network workload, and inconvenience in disaster recovery. To overcome these disadvantages, we propose a channel bonding technique and provide hot backup functions in the designed NAS system, named HUSTserver. Channel bonding means merging multiple Ethernet channels into integrated one, and that the data packets can be transferred through any available network channels in a parallel mode. The hot backup function provides automatic data mirroring among servers. In this paper, we first describe the whole system prototype from a software and hardware architecture view. Then, multiple Ethernet and hot backup technologies that distinguish HUSTserver from others are discussed in detail. The findings presented demonstrate that network bandwidth can be scaled by the use of multiple commodity networks. Dual parallel channels of commodity 100 Mbps Ethernet are both necessary and sufficient to support the data rates of multiple concurrent file transfers. And the hot backup function introduced in our system provides high data accessibility.

Performance analysis of an iSCSI-based unified storage network

In this paper, we introduced a novel storage architecture 'Unified Storage Network', which merges NAC( Network Attached Channel) and SAN( Storage Area Network) , and provides the file I/O services as NAS devices and provides the block I/O services as SAN. To overcome the drawbacks from FC, we employ iSCSI to implement the USN( Unified Storage Network) . To evaluate whether iSCSI is more suitable for implementing the USN, we analyze iSCSI protocol and compare it with FC protocol from several components of a network protocol which impact the performance of the network. From the analysis and comparison, we can conclude that the iSCSI is more suitable for implementing the storage network than the FC under condition of the wide-area network. At last, we designed two groups of experiments carefully.

Security System in United Storage Network and Its Implementation

With development of networked storage and its applications, united storage network (USN) combined with network attached storage (NAS) and storage area network (SAN) has emerged. It has such advantages as high performance, low cost, good connectivity, etc. However the security issue has been complicated because USN responds to block I/O and file I/O requests simultaneously. In this paper, a security system module is developed to prevent many types of attacks against USN based on NAS head. The module not only uses effective authentication to prevent unauthorized access to the system data, but also checks the data integrity. Experimental results show that the security module can not only resist remote attacks and attacks from those who has physical access to the USN, but can also be seamlessly integrated into underlying file systems, with little influence on their performance.

File Assignment Policy in Network Storage System

Network storage increase capacity and scalability of storage system, data availability and enables the sharing of data among clients. When the developing network technology reduce performance gap between disk and network, however, mismatched policies and access pattern can significantly reduce network storage performance. So the strategy of data placement in system is an important factor that impacts the performance of overall system. In this paper, the two algorithms of file assignment are presented. One is Greed partition that aims at the load balance across all NADs (Network Attached Disk). The other is Sort partition that tries to minimize variance of service time in each NAD. Moreover, we also compare the performance of our two algorithms in practical environment. Our experimental results show that when the size distribution (load characters) of all assigning files is closer and larger, Sort partition provides consistently better response times than Greedy algorithm. However, when the range of all assigning files is wider, there are more small files and access rate is higher, the Greedy algorithm has superior performance in compared with the Sort partition in off-line.

NASSN:a NAS-based storage network

With the digital information and application requirement on the Internet increasing fleetly nowadays,it is urgent to work out a network storage system with a large capacity,a high availability and scalability.To solve the above-mentioned issues,a NAS-based storage network(for short NASSN)has been designed.Firstly,the NASSN integrates multi-NAS,iNAS(an iSCSI-based NAS)and enterprise SAN with the help of storage virtualization,which can provide a greater capacity and better scalability.Secondly,the NASSN can provide high availability with the help of server and storage subsystem redundancy technologies.Thirdly,the NASSN simultaneously serves for both the file I/O and the block I/O with the help of an iSCSI module,which has the advantages of NAS and SAN.Finally,the NASSN can provide higher I/O speed by a high network-attached channel which implements the direct data transfer between the storage device and client.In the experiments,the NASSN has ultra-high-throughput for both of the file I/O requests and the block I/O requests.

Research on the Security of the United Storage Network Based on NAS

A multi-user view file system (MUVFS) and a security scheme are developed to improve the security of the united storage network (USN) that integrates a network attached storage (NAS) and a storage area network (SAN). The MUVFS offers a storage volume view for each authorized user who can access only the data in his own storage volume, the security scheme enables all users to encrypt and decrypt the data of their own storage view at client-side, and the USN server needs only to check the users’ identities and the data’s integrity. Experiments were performed to compare the sequential read, write and read/write rates of NFS+MUVFS+secure_module with those of NFS. The results indicate that the security of the USN is improved greatly with little influence on the system performance when the MUVFS and the security scheme are integrated into it.

Design of Enterprise Storage Architecture for Optimal Business Continuity

This paper presents a solution for optimal business continuity, with storage architecture for enterprise applications, which will ensure zero data loss and quick recovery. The solution makes use of Internet protocol storage area network （IPSAN）, which is used for data management without burdening the application server, as well as mix of synchronous and semi-synchronous replication techniques to replicate data to remote disaster recovery site. We have presented the detailed design of both synchronous and semi-synchronous with case study of using open source database postgres to prove our point for optimal business continuity. The theoretical presentation is also given for the same.

Distributed Storage Cluster Design for Remote Mirroring Based on Storage Area Network

With the explosion of information nowadays, applying data storage safety requirements has become a new challenge, especially in high data available cluster environments. With the emergence of Storage Area Networks （SANs）, storage can be network-based and consolidated, and mass data movements via Fiber Channels （FCs） can be of very high speed. Based on these features, this paper introduces a dual-node storage cluster designed for remote mirroring as a concurrent data replication method to protect data during system failures. This design takes full advantage of a SAN system＇s benefits, and it adopts a synchronous protocol to guarantee a fully up-to-date data copy on the remote site. By developing a Linux kernel module to control the I/O flow and by using the technologies of software Logic Unit Number （LUN） masking, background online resynchronization and a self-management daemon, we have achieved a reliable mirroring system with the characteristics of server-free data replication, fault tolerance, online disaster recovery and high performance. In this study, we implemented the design in a remote mirror subsystem built on a software Fiber Channel Storage Area Network （FC-SAN） system.

基于圩区产流与调蓄的大型平原河网水文水动力耦合模型研究

构建可靠的水文水动力模型是减轻平原河网洪涝灾害的必要手段。以太湖流域杭嘉湖区为例,采用MIKE11和ArcGIS,通过河网概化、集水区划分、圩区内外独立的产汇流计算和调蓄分析等环节构建了杭嘉湖平原河网水文水动力耦合模型,选用“菲特”和“烟花”台风实测洪水数据验证了模型可行性。结果显示,模拟水位与实测水位绝对值相差0.01~0.09 m,水量结果误差为5.4%,表明模型准确可靠。本模型可为该地区防洪调度、工程规模论证等相关工作提供技术支撑,也可为相似地区水文水动力耦合模型的构建提供理论指导。

基于空间变换与平滑处理的PACS医学影像数据存储系统研究

为实现影像资源的高速传输与共享,提升诊断效率与医疗质量,设计基于空间变换与平滑处理的PACS医学影像数据存储系统。经过融合网络附属存储模块与存储区域网络模块,将组建的NAS-SAN存储模型作为图像存档与传输系统的存储单元,结合采集单元、存储与管理单元等组件以及医学影像的空间变换与平滑处理算法,建立PACS医学影像数据存储系统。实验环节从模块功能、响应性等多个角度来反映系统运行效果,结果表明,所建系统能够实现预期设计目标、响应速度与并行性理想。

基于区块链的能源局域网储能优化调度研究

为实现能源局域网内新能源高效消纳、优势互补的目标,提出基于区块链的能源局域网储能优化调度研究。首先,基于区块链技术建立能源局域网能量流与信息流结合的模型,设计储能优化调度智能合约;其次,建立储能能量损耗最小和经济效益最大的双目标优化调度模型,以实现能源局域网综合效益最优;最后,通过算例仿真分析证明了所提方法不仅能保证储能主体交易信息公开透明,同时也为能源局域网储能实现综合效益最优提供依据。

基于台区融合终端的分布式储能型光伏并网电能质量研究

为解决并网光伏发电系统电能质量波动问题,提出了基于台区融合终端的光伏储能并网电能质量系统设计方案。分析了分布式储能型光伏并网的基本框架,说明了电能质量监测的基本参数。设计了台区融合终端电能治理方案,分为融合终端配合储能系统电能治理、融合终端配合储能PCS电能治理和融合终端配合智能光伏隔离开关电能治理3种方案。针对电池储能PCS系统进行设计,说明了智能光伏隔离开关的主要技术原理和微应用总体架构。最后针对某地区电网实际光伏并网进行应用分析。

家庭云NAS研究及推广策略

随着智能家居、高清视频以及全民泛资讯新媒体业务的发展,个人与家庭所需的存储容量急剧增长。传统的家庭存储面临价格昂贵、使用复杂、安全无保障以及访问速度慢等缺点,无法满足用户需求。利用庞大的千兆家庭宽带用户基础和云计算的技术优势,运营商具备切入家庭存储市场的便利条件。文章详细分析了家庭云存储的特点、场景及技术架构,针对用户痛点分析如何推广家庭云产品。

发电企业技术资料数字化管理模式探索

发电企业设备多,相关的接线图纸、说明书、作业指导书、异动记录等资料繁多,资料文件是维护人员、设备技术管理人员开展工作的依据,如果缺乏科学、规范的管理方式,将严重影响工作效率。随着企业设备的不断更新,和逐年进行的设备检修、技术改造、设备异动等工作,相关的图纸、说明书等资料文件数量增长呈现几何增长态势,如何高效、准确的查阅图纸、设备资料和快速的实现文件管理十分关键,科学、有效的设备图纸、资料管理模式将极大的解放发电企业生产技术管理的生产力。

Performance Comparison of IP-Networked Storage

Dramatically increasing amounts of digital data are placing huge requirements on storage systems.IP-networked storage systems, such as the network file system （NFS）-based network-attached storage （NAS） systems and the iSCSl-storage area network （SAN） systems, have become increasingly common in today＇s local area network （LAN） environments. The emergence of new storage techniques, such as object-based storage （OBS） and content aware storage （CAS）, significantly improves the functionality of storage devices to meet further needs for storage sub-systems. However, these may impact system performance. This papercompares the performance of NFS, iSCSI storage, object-based storage devices （OSDs）, and CAS-based storage systems in an environment with no data sharing across host machines. A gigabit ethernet network is used as the storage network. Test results demonstrate that the performances of these systems are compa- rable with CAS being much better than the others for write operations. The performance bottlenecks in these systems are analyzed to provide insight into how future storage systems may be improved and possible optimization methods. The analysis shows how the I/O interfaces in these systems affect the application performance and that network-based storage systems require optimized I/O latency and reduced network and buffer processing in the servers.

改进新能源消纳的配电网资源优化配置研究

随着大规模分布式发电接入配电网,其出力与负荷需求在时序上的不匹配性引起供电区域新能源难以消纳。为此,提出提升新能源消纳能力的供电区域源-荷-储联合优化配置方法。以配电网供电区域分布式电源、储能及可控负荷为配置对象,构建储能及可控负荷调用策略;建立供电区域源荷储二层联合优化配置模型。上层模型以实现分布式电源的最大消纳为优化目标。下层模型以供电区域内净负荷期望值峰谷差最小为优化目标。针对DG及负荷出力时序差异性,采用LHS技术进行处理;采用智能优化算法对模型进行求解。以某市供电区域拓扑结构为例进行算例分析,证明方法的合理性与有效性。

考虑风电功率预测误差分时补偿的电热联合系统多时间尺度调度

由于风电具有不确定性,风电功率预测误差难以避免。热力系统具备储放热能力,通过调整热功率平移风电功率,可以降低风电功率预测误差的影响。但在风电并入电热联合系统时,风电变化频繁,热力系统具有较大惯性和延迟,难以与风电功率同步;同时,热力系统不同区域对电力系统指令的响应速度也不同。因此,为了解决利用热力系统补偿风电功率预测误差时响应时间不同步的问题,提出了一种考虑风电功率预测误差分时补偿的电热联合系统多时间尺度调度策略。首先,分析概率区间误差评估和实时预测误差评估的评估周期。然后,研究热力系统中供热区域和管网的时间特性。最后,在日前阶段利用响应速度较慢的供热区域补偿评估周期较长的概率区间误差,在实时阶段利用响应速度较快的管网补偿评估周期较短的实时预测误差,建立了多时间尺度调度模型。算例分析表明,所提策略实现了不同调度周期、不同预测误差评估周期、不同热力系统区域响应速度在时间上的匹配,减少了风电功率预测误差的影响,提高了系统的风电消纳能力。

Design and Implementation of a Storage Virtualization System Based on SCSI Target Simulator in SAN

The ideal storage virtualization system is compatible with all operating systems in storage area networks (SANs). However, current storage systems on clustered hosts and multiple operating systems are not practical. This paper presents a storage virtualization system based on a SCSI target simulator in a SAN to solve these problems. This storage virtualization system runs in the target hosts of the SAN, dynamically stores the physical information, and uses the mapping table method to modify the SCSI command addresses. The system uses the bitmap technique to manage the free space. The storage virtualization system provides various functions, such as logical volume resizing, data mirroring, and snapshots, and is compatible with clustered hosts and multiple operating systems, such as Windows NT and RedHat.

基于改进GoogLeNet的汽车仓储库区障碍物分类识别方法

针对汽车仓储库区的特点,提出了一种基于改进GoogLeNet卷积神经网络的仓储库区障碍物分类识别方法,即对传统GoogLeNet卷积神经网络浅层的Inception模块进行改进,并在此基础上增加四分类全连接层,改进后的卷积池化层作为仓储库区四分类图像数据的特征提取器,对全连接层和输出层进行模型训练。实验结果表明:该障碍物分类识别方法准确率高且识别时间短,大大增加了AGV障碍物检测系统的准确性与鲁棒性。