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In this paper, we study a novel transmission framework based on statistical channel state information (SCSI) by incorporating edge caching and beamforming in a fog radio access network (F-RAN) architecture. By optimizing the statistical beamforming and edge caching, we formulate a comprehensive nonconvex optimization problem to minimize the backhaul cost subject to the BS transmission power, limited caching capacity, and quality-of-service (QoS) constraints. By approximating the problem using the l 0 -norm, Taylor series expansion, and other processing techniques, we provide a tailored second-order cone programming (SOCP) algorithm for the unicast transmission scenario and a successive linear approximation (SLA) algorithm for the joint unicast and multicast transmission scenario. This is the first attempt at the joint design of statistical beamforming and edge caching based on SCSI under the F-RAN architecture.

A special strain of situational impairment, termed “Severely Constraining Situational Impairments” (SCSI), was explored from a novel qualitative perspective. When a severely impairing event presents, the multitude and complexity of ambient agents are often overwhelming, leading to the inability to devise a solution. To classify and help design for them, interviews and participatory design-based workshops were conducted, revealing that (1) participants attempt to complete mobile transactions, even if it might place them in considerable danger, and (2) significant differences exist in the modalities and steps used to address the onset of a severely impairing event versus those of a non-severe situational impairment. Design solutions generated from the workshops indicated that users want technology to take a larger role in helping manage the added cognitive load inherent in severely impairing events. The revealed implications for design indicate that to maximize the user experience in the mobile device transaction space, designers must account for the presence of these SCSI and the unique design specifications that they require.

Objectives: Developmental programming must work. Following quite a while of vital investigation into open private key sets, we disconfirm the development of Boolean rationale, which typifies the imperative standards of equipment and engineering. Methods/Statistical Analysis: So as to defeat this issue, we utilize interposable innovation to show that the acclaimed established calculation for the development of SCSI circles which keeps running in Ω(n2) time. Findings: We discredited that regardless of the way that the original psychoacoustic calculation for the refinement of computerized to simple converters. Application: FernyMarc might have the capacity to effectively give numerous neural networks without a moment\'s delay. Keywords: FerntMarc, RAID, XML

Non-orthogonal multiple access (NOMA) and millimeter wave (mmWave) are two key enabling technologies for the fifth-generation (5G) mobile networks and beyond. In this paper, we consider mmWave NOMA systems with max-min fairness constraints. On the one hand, existing beamforming designs aiming at maximizing the spectrum efficiency (SE) are unsuitable for the NOMA systems with fairness in this paper. On the other hand, previous work on about mmWave NOMA mostly depends on full knowledge of channel state information (CSI) which is extremely difficult to obtain accurately in mmWave communication systems. To address this problem, we propose a heuristic hybrid beamforming design based on the statistical CSI (SCSI) user grouping strategy. An analog beamforming scheme is first proposed to integrate the whole cluster users to mitigate the inter-cluster interference in the first stage. Then two digital beamforming designs are proposed to further suppress the interference based on SCSI. One is the widely used zero forcing (ZF) approach and the other is derived from the signal-to leakage-plus-noise ratio (SLNR) metric extended from orthogonal multiple access (OMA) systems. The effective gains fed back from the users are used for the power allocation. We introduce the quadratic transform (QT) method and bisection approach to reformulate this complex problem so as to rend it solvable. Simulation results show that our proposed algorithms outperform the previous algorithms in term of user fairness.

The Southern Connecticut Stellar Interferometer (SCSI) is an intensity interferometer that is designed to use correlated photon arrival times to determine the geometry of stars. Originally a low-cost, two-telescope instrument that used a 1-pixel single-photon avalanche diode (SPAD) detector at the focal plane of each telescope to record photon events, it is now being upgraded to include a third telescope. This will allow for the simultaneous detection of the photon correlation at three baselines, and thus the ability to map out the two-dimensional geometry of the source much more efficiently than with the two-telescope arrangement. Recent papers in the literature suggest that it may be possible to derive phase information in the Fourier domain from such triple correlations for the brightest stars, potentially giving SCSI an imaging capability. Prior to investigating this possibility, steps must be taken to maximize the observing efficiency of the SCSI. We present here our latest efforts in achieving better pointing, tracking, and collimation with our telescopes, and we discuss our first modeling results of the three-telescope situation in order to understand under what conditions the upgraded SCSI could retrieve imaging information.

In this paper, we propose a method to predict the average packet error rate (PER) of a coded single carrier frequency domain equalization (SC-FDE) transmission scheme after minimum mean square error (MMSE) equalization when statistical channel state information (SCSI) is available. We assume that the encoded bits are spread over several blocks (which may correspond to a frequency hopping system for instance) which are transmitted under independent multipath random fading channel realizations. The PER prediction technique used here is based on the effective SNR mapping approach that gathers the signal to noise ratios (SNR)s of the different blocks into one single value. The novelty of this contribution resides in the fact that we propose a new expression for the effective SNR that allows us to approximate its statistical distribution with a beta random variable whose parameters depend on the SCSI. This approach enables us to compute the PER prediction with a lower complexity that the one required by conventional approaches. Moreover, we show by simulations that the accuracy of our solution is very close to the conventional ones, typically within 1 dB of error for PER of the order of $10^{-2}$.

iSCSI is an IP based SAN technology, that carrying SCSI commands over TCP/IP. Ceph integrates iSCSI Target as a gateway to provide block layer storage service. A single iSCSI Target could be a system bottleneck because of its computing and I/O performance limitations. However, current software-defined iSCSI Targets can not cooperate on handling SCSI3 Persistent Reservation with each other in an iSCSI Target cluster. In this paper, we have proposed and implemented a mechanism that can synchronize the SCSI3 Persistent Reservation status of an iSCSI LUN among a cluster of Linux iSCSI Targets. By feats of this feature, it would become possible to set up a cluster of iSCSI Targets hosting mutual Ceph RBD images with active/active connections to meet high-performance and high availability requirements of modern business.

Uniaxial strength (UCS), tensile strength (BTS), and elastic modulus (E) are important rock strength parameters used in many engineering projects such as dam, bridge, and tunnel constructions. Several direct and indirect methods have been proposed to measure these parameters. For direct methods, standard samples should be prepared and loaded. Indirect methods are used to estimate these parameters when there is no access to the standard core for various reasons. In this regard, the single compressive strength test (SCS) is one of the indirect methods for estimating these parameters using small specimens. In the present study, the possibility of using SCS test for predicting strength parameters of marlstones is investigated. For this purpose, a total of 10 marlstone blocks were collected from different geological formations of Iran. After preparation of the standard samples, an attempt was made to determine uniaxial strength (UCS), Brazilian tensile (BTS), and elastic modulus (E) of each sample. Next, the samples were crushed and 50 small spherical particles with diameters of 3, 5, 8, 9, and 10 mm were prepared from each sample. A total of 500 particles were used for SCS testing. Then, the single compressive strength index (SCSI) was determined for each particle by plotting load-displacement diagrams; the SCSI of each sample was the average SCSI of 10 same size particles. Subsequently, UCS-SCSI, E-SCSI, and BTS-UCS correlations for specific particle sizes were proposed using the regression analysis. The mean values for the correlation coefficients were obtained as 0.93, 0.89, and 0.91, respectively. The empirical relationships were verified by conducting 100 tests on the control samples, which revealed the reliable validity of the outcomes. The results of this regression modeling, compared with the data obtained from SCS experiments on limestone and sandstone particles mentioned in the literature, demonstrated that the empirical relationships were affected by rock types. Therefore, rock-specific diagrams have to be drawn for particles with different lithologies.

Sc-doped semiconductor clusters are the simplest transition metal- and rare-earth metal-doped semiconductor clusters. In this work, the structural evolution behavior and electronic properties of Sc...

This study focuses on local channel correlation based zero-forcing (ZF) precoding design for boosting weighted ergodic sum-rate (WESR) in the cooperative two-cell multiple-input single-output system. We first present that the WESRs of the statistical channel state information (SCSI) aided general eigenvector coordinated beamforming (SCSI-GE) and the conventional ZF beamforming with erroneous instantaneous channel state information (ICSI; eICSI-ZF) saturate to constant values at high SNR due to inter-cell interference. Motivated by this, we develop a ZF coordination framework with local SCSI requirement at the transmitter and low data-sharing backhaul load. Additionally, a low-cost but effective two-dimensional ZF precoding design called 2d-SZF is proposed, which involves only distributed computations based on the local channel correlation. Theoretical analysis and simulation results confirm that the proposed local SCSI-based 2d-SZF scheme yields the most desirable WESR while the WESRs of SCSI-GE and eICSI-ZF both saturate in the high regime of SNR, and are respectively sensitive to the level of spatial channel correlation and ICSI accuracy at finite SNR.

A hybrid precoding scheme is proposed for high altitude platform (HAP) massive multiple-input multiple-output (MIMO) systems to obtain the radio frequency (RF) precoder and the baseband precoder with limited RF chains. We first exploit duality theory to derive the relation between the statistical channel state information (SCSI) and RF precoder, which is selected from a predefined codebook. Then, the baseband precoder is attained by zero forcing (ZF) based on the instantaneous effective channel matrix. A distinct performance gain is achieved by the proposed scheme according to the numerical results.

Supply chain sustainability (SCS) is an approach that takes into consideration the environmental, economic, and social aspects of the supply chain processes, components, technologies, and logistics when designing a supply chain network. The elements that impact SCS encompass all kinds of waste, emissions, green management, workers’ health and well-being, market competitiveness, transportation, and financial aspects of the network. Supply chain experts should integrate sustainability practices in different phases of the supply chain and encourage organizations to orient their efforts toward designing sustainable supply chains. In this study, we present a new metric, “supply chain sustainability index (SCSI)” to assess the overall sustainability of a biomass supply chain network through three criteria: environmental, social, and economic sustainability. To pursue the objective of the study, a Bayesian Network approach is implemented to depict the causal relationship among different variables and to demonstrate a better analysis of the subject. For further assessment and analysis of the overall sustainability of the supply chain network, sensitivity analysis and belief propagation are performed. Results indicate that all three criteria are imperative to SCSI prediction; however, economic sustainability has a slightly higher effect among the three criteria, while social criteria have the lowest effect on SCSI.

Climate-Smart Agriculture (CSA) has had an increasing role in the agricultural policy arena, as it aims to address climate change mitigation, adaptation and food security goals in an integrated way. In regions where agriculture has been constrained because of soil degradation and climate change, CSA aims to implement soil-based strategies that restore soil function and increase carbon storage. The extent to which such strategies succeed in achieving mitigation, adaptation and productivity goals is referred to as climate-smartness. The co-evolution of yield and Soil Organic Carbon (SOC) over the years presents a proxy for the trade-off between productivity, soil fertility and carbon sequestration. Yield and SOC are widely monitored, analysed and used to inform CSA planning. Yet their analysis is often conducted separately and for a small number of years, which neglects long-term soil fertility dynamics and their impact on crops. Given the absence of integrated climate-smartness metrics to capture the trade-offs and synergies between SOC and yield, we present a soil-based Climate-Smartness Index (SCSI). The SCSI is computed using normalized indicators of trend and variability of annual changes on yield and SOC data. The SCSI was calculated for a set of published experiments that compared Conservation Agriculture (CA) practices with conventional management. The CA treatments scored higher SCSI during the first 5 years of evaluation as compared to conventional management. Analysis of the temporal dynamics of climate-smartness indicated that minimum SCSI values typically occurred before 5 years after the start of the experiment, indicating potential trade-offs between SOC and yield. Conversely, SCSI values peaked between 5 and 10 years. After 20 years, the SCSI tended towards zero, as substantial changes in either SOC or yield are no longer evidenced. The SCSI can be calculated for annual crops under any soil management and at different time periods, providing a consistent metric for climate-smartness across both practices and time.

Primary objective of SST-1 Plasma control system is to achieve Plasma position, shape and current profile control. Architecture of control system for SST-1 is distributed in nature. Fastest control loop time requirement of 100 μs is achieved using VME based simultaneous sampling ADCs, PMC based quad core DSP, Reflective Memory [RFM] based real-time network, VME based real-time trigger distribution network and Ethernet network. All the control loops for shape control, position control and current profile control share common signals from Magnetic diagnostic so it is planned to accommodate all the algorithms on the same PMC based quad core DSP module TS C-43. RFM based real-time data network replicate data from one node to next node in a ring network topology at sustained throughput rate of 13.4 MBps. Real-time Timing System network provides guaranteed trigger distribution in 3.8 μs from one node to all node of the network. Monitoring and configuration of different systems participating in the operation of SST-1 is done by Ethernet network. Magnetic sensors data is acquired using Pentek 6802 simultaneously sampling ADC card at the rate of 10KSPS. All the real-time raw data along with the control data will be archived using RFM network and SCSI HDD for the experiment duration of 1000 s. RFM network is also planned for real-time plotting of key parameter of Plasma during long experiment. After experiment this data is transferred to central storage server for archival purpose. This paper discusses the architecture and hardware implementation of the control system by describing all the involved hardware and software along with future plans for up-gradations.

Wood in outdoor conditions is prone to water uptake and release. The influence of wood temperature and moisture on the decay risk is substantial. Different climate indexes and mathematical models have been used to predict the decay risk, being one of the most well-known is the Scheffer index (SI). Scheffer index values (SI1) and modified Scheffer index values considering days with no rain but condensation (SI2) together with the risk of physical and dimensional degradation of wood (RDA) and the severity climate indexes (summer and winter) are calculated for 48 capitals of province in Spain. The relationships between the risk of physical degradation of the wood (RDA) and the climatic severity variables both for summer (SCSI) and winter (WCSI) are analyzed, and a model for predicting the RDA value from the SCSI and WCSI values is proposed. The analysis of the relationship between the Scheffer index (SI1) and SCSI and WCSI variables leads to the conclusion that the decay risk is fundamentally governed by summer climatic severity (SCSI) in coastal areas and by both variables (SCSI and WCSI) in inland areas, the relative insolation value being the variable with the most significant effect, both in summer and winter. The effect of condensations on the decay risk is also assessed, leading to the conclusion that the frequent presence of condensation is an aggravating factor and therefore, this meteorological variable should be considered when calculating the decay risk. A new equation for SI calculation considering the condensation effect, together with a new rating of risk, is also provided. © 2016, Springer-Verlag Berlin Heidelberg.

This paper provides an overview of NVME technology and discusses the relevance to the digital forensics community. The NVM Express standard defines an interface and command set for communication between a host and non-volatile memory devices (SSD's). It allows the direct attachment of SSD storage to the PCI Express bus using PCIe slots, M.2, and U.2 interfaces. NVME was developed with a new command set and is not compatible with ATA/ATAPI or SCSI commands. The introduction of NVME to the market creates new challenges when performing digital forensic acquisition and analysis, where legacy drive commands are expected.

To build a point to point data transfer system with a configurable protocol, the FPGA devices are used as a cheaper alternative versus ASIC; especially if every data package must be synchronous with a single clock signal for both receiver and transmitter. A brief description of the desired system, hardware programming that rules the communication protocol, design and fabrication of the printed circuit board that makes possible the communication between two FPGA Mezzanine Card through SCSI cable and the final testing of the system, are the followed steps to perform this flexible and high velocity scientific research oriented system.

The Southern Connecticut Stellar Interferometer (SCSI) is a two-telescope astronomical intensity interferometer that was completed in June 2016 and has been taking photon correlation data since that time. It uses single-photon avalanche diode (SPAD) detectors at the telescope focal plane and a central timing module, which records the signals from both telescopes simultaneously. In the observations taken to date, single-pixel SPADs have been connected to signal cables that stretch from each telescope to the timing module. However, we are now in the process of making the instrument “wireless” by using a separate timing module at each telescope and synchronizing the signals recorded using GPS timing cards. We have also upgraded one of the two stations with an 8-pixel SPAD device, which allows us to achieve higher count rates in a variety of observing conditions. In this paper, we report on the current state of the instrument, including engineering tests made in preparation for wireless operation, and we discuss the expected capabilities in that mode.

The open-source framework for stream processing and enormous information In-memory handling model executed with the machine learning algorithms The data used in subset of non-distributed mode is better than using all data in distributed mode The Apache Spark platform handles big data sets with immaculate parallel speedup.

In this paper, we investigate the secrecy outage performance of a dual-hop decode-and-forward (DF) threshold-based cooperative relay network, both with and without the direct links between source-eavesdropper and source-destination. Without assuming that all the relays can always perfectly decode, here we consider that only those relays who satisfy predetermined threshold can correctly decode the message. We have investigated the outage probability of optimal relay selection scheme, when either full instantaneous channel state information (ICSI) or statistical channel state information (SCSI) of all the links is available. We have shown that CSI knowledge at the transmitter can improve secrecy, and the amount of improvement for the outage probability is more when the required rate is low and for low operating SNR. Asymptotic and diversity gain analysis of the secrecy outage for both the single relay and multi-relay system is obtained, when average SNRs of source-relay and relay-destination links are equal or unequal. We have shown that the improvement in predetermined threshold, eavesdropper channel quality, direct links, and required secrecy rate significantly affects the secrecy performance of the system.

A subset of “Situationally Induced Impairments and Disabilities” (SIID), termed “Severely Constraining Situational Impairments” (SCSI), was explored at the user task and motivational level, to better understand the challenges faced by users attempting to perform tasks using a mobile device. Through structured interviews, participants were found to deploy workarounds in attempting to complete mobile I/O transactions, even if that workaround might place them in considerable danger. The motivations underlying user decisions were also explored resulting in a set of rich scenarios which will be used in the final participatory design stage of the study to discover ways that technology can be designed to overcome SCSIs.

Internet-based virtual computing environment (iVCE) has been proposed to combine data centers and other kinds of computing resources on the Internet to provide efficient and economical services. Virtual machines (VMs) have been widely used in iVCE to isolate different users/jobs and ensure trustworthiness, but traditionally VMs require a long period of time for booting, which cannot meet the requirement of iVCE’s large-scale and highly dynamic applications. To address this problem, in this paper we design and implement VirtMan, a fast booting system for a large number of virtual machines in iVCE. VirtMan uses the Linux Small Computer System Interface (SCSI) target to remotely mount to the source image in a scalable hierarchy, and leverages the homogeneity of a set of VMs to transfer only necessary image data at runtime. We have implemented VirtMan both as a standalone system and for OpenStack. In our 100-server testbed, VirtMan boots up 1000 VMs (with a 15 GB image of Windows Server 2008) on 100 physical servers in less than 120 s, which is three orders of magnitude lower than current public clouds.

With the recent big-data processing in multimedia devices becoming a popular application, a fast and energy efficient storage area network system for smart classroom is required. Traditional storage management system for smart classroom show low performance when small read and write operations are executed. This paper proposes a smart classroom storage management system (SCSMS) which consists of new adaptive chunking and XOR reference matrix based erasure coding techniques for multimedia devices with higher input/output performance and low energy consumption. The SCSI initiator is installed in multimedia devices such as smart TVs, smart phones and personal computers. The proposed adaptive chunking and exclusive-or (XOR) reference matrix-redundant array of inexpensive disks (XRM-RAID)are provided at a target server based on flash array storage, respectively. Adaptive chunking differs from traditional chunking in that it reduces the number of read and write operations by merging small files into a united chunk. XRM-RAID differs from existing RAID in that it reduces the number of XOR operations to generate parity data in the RAID system. This paper provides web based monitoring application of the proposed SCSMS. Experimental results show that the energy consumption of the proposed SCSMS is improved by 32 %, 42 % and 58 % compared to Huang et al., Kim et al. and Scott et al. with respect to file size and buffer size. In terms of the average write throughput, the proposed SCSMS has higher performance by 22 %, 32 % and 56 % compared to Huang et al., Kim et al. and Scott et al. with respect to file size and buffer size.

With the rapid diffusion of a wide variety of smartphones, quality issues have become central to consumers. While customer satisfaction of most goods and services has been well researched, little research seems to exist on satisfaction and loyalty with respect to advanced mobile services, such as smartphones. This study applied a customer satisfaction index (CSI) model to the smart mobile sector in order to derive a smart-service CSI (SCSI). The SCSI model and its hypotheses were then tested using partial least square analysis and index calculation. The findings showed that the perceived value and customer satisfaction are key variables mediating the relationship between quality and customer loyalty. The proposed model demonstrated strong explanatory power, with satisfactory reliability and validity. The SCSI model establishes a foundation for future smart service categories on the basis of providing a powerful tool for quality assessment. The results of this study provide useful insights for the telecom industry and policymakers, for the forging of effective policies and competitive strategies.

A network may contain links with variable discrete bandwidth, e.g., microwave and copper. The bandwidth of such links may change discretely in response to a changing external environment. The word "availability" is typically used to describe such links during network planning. This document defines a new type of Generalized Switching Capability-Specific Information (SCSI) TLV to extend the Generalized Multiprotocol Label Switching (GMPLS) Open Shortest Path First (OSPF) routing protocol. The extension can be used for route computation in a network that contains links with variable discrete bandwidth. Note that this document only covers the mechanisms by which the availability information is distributed. The mechanisms by which availability information of a link is determined and the use of the distributed information for route computation are outside the scope of this document. It is intended that technology-specific documents will reference this document to describe specific uses.

In this work, the low-lying states of several isomers of ScSi n −/0 (n = 4–6) were investigated with the B3LYP functional and CASPT2 method. The ground states of the anionic clusters were predicted to be the singlet states of the trigonal bipyramid ScSi4 − (A-ScSi4 −), the face-capped trigonal bipyramid ScSi5 − (A-ScSi5 −), and the pentagonal bipyramid ScSi6 − (A-ScSi6 −) isomer. Based on the anionic ground states, all the relevant electron detachment processes were identified. The corresponding adiabatic and vertical detachment energies (ADEs and VDEs) of the anionic clusters were computed at the CASPT2 level. The calculated results were used to interpret all the important features in the photoelectron spectra of ScSi n − (n = 4–6) clusters. Franck-Condon factor simulations were also performed based on the B3LYP geometries, vibrational frequencies, and normal modes to explain the shapes of the first bands in the spectra.

New green-emitting KBa 1− x ScSi 3 O 9 :Eu 2+ x phosphors for white LEDs were synthesized by a conventional solid-state reaction method. The obtained KBa 1− x ScSi 3 O 9 :Eu 2+ x phosphors show the strong broad optical absorption band from UV to blue light region and exhibit broad green emission with a peak at 521 nm under excitation at 405 nm due to the allowed 4f 6 5d 1 −4f 7 transition of Eu 2+ . Optimization of Eu 2+ concentration resulted in the highest green emission peak intensity was obtained at the composition of KBa 0.94 ScSi 3 O 9 :Eu 2+ 0.06 , and the relative emission intensity of this phosphor was 32% of that of a commercial YAG:Ce 3+ phosphor.

The heat contents (H T − H 298K) of Sc5Si3 and ScSi in the Sc–Si system were measured by drop calorimetry method from 400 to 1,200 °C in the present work. Based on the critically reviewed thermodynamic properties and phase diagram data from the literature and the present work, the Sc–Si system was assessed by means of the CALPHAD (CALculation of PHAse Diagram) approach. The Gibbs energies of solution phases, Liquid, (αSc), (βSc), and (Si), were modeled by the Redlich–Kister polynomial. All the intermetallic compounds, Sc5Si3, ScSi, αSc3Si5, and βSc3Si5, were described as stoichiometric phases. Finally, a set of self-consistent thermodynamic parameters for the Sc–Si system was obtained. The calculated phase diagram and thermodynamic properties agree well with the available experimental data.

SCST(The generic SCSI target subsystem for Linux) enables developers to make SCSI target storage and supports various SCSI network protocol such as iSCSI, FC, SRP. In this paper, we propose storage virtualization method using SCST and virtualize all flash array as high performance storage through 4Gb Fiber Channel, 10Gb Ethernet and 40Gb Infiniband and evaluate their performance, respectively. Experimental result shows that 40Gb infiniband network appliance have better performance than others. In case of sequential/random read, 40Gb infiniband network appliance shows 78% and 79% of local all flash array performance attached to SCSI target system. In case of sequential/random write, it shows 83% and 88% of local flash array performance attached to SCSI target system.

This paper investigates the performance of a two-hop amplify-and-forward (AF) relay network with antenna correlation and co-channel interference (CCI) over Rayleigh fading channels. In this network, the relay has multiple antennas while both the source and destination are equipped with a single antenna. By assuming that the statistical channel state information (SCSI) is available at the relay, the maximal output signal-to-interference-plus-noise ratio (SINR) is first obtained. Then, with the help of the specialized functions, the analytical expressions for the outage probability (OP), Ergodic capacity and average symbol error rates (ASERs) of the considered AF relay network are all derived. Moreover, the asymptotic analysis at high signal-to-noise ratio (SNR) is also presented to reveal the diversity order and array gain of the relay system. Finally, computer simulations are given to confirm the validity of the theoretical analysis and indicate the effects of antenna correlation and interference on the system performance.

Small Computer System Interface (SCSI) is a set of protocols used for communication and data transfer between I/O devices like computers and storage devices. SCSI standards include various commands, interfaces and protocols that are required to communicate with devices such as hard disks, DVD and printers. iSCSI is a storage standard for exposing and utilizing data storage devices over network using TCP/IP protocol. iSCSI provides remote data operations by performing SCSI commands over TCP/IP networks. This paper explains the features of various iSCSI Target Frameworks currently in use, such as SCSI Target Framework (STGT), Generic SCSI Target Subsystems for Linux (SCST), Linux I/O Target (LIO), iSCSI Enterprise Target (IET). The paper also presents a comparison of the features of these implementations.

Purpose – The development of micro‐electro‐mechanical systems (MEMS) for use in military and consumer electronics necessitates an analysis of MEMS component reliability. The understanding of the reliability characteristics of SCSi within MEMS structures should be improved to advance MEMS applications. Reliability assessments of MEMS technology may be used to conduct virtual qualification of these devices more efficiently. The purpose of this paper is to create a simple, inexpensive test methodology to use the dynamic fracture strength of a MEMS device to predict its reliability, and to verify this method through experimentation.Design/methodology/approach – The dynamic fracture strength of single crystal silicon (SCSi) was used to model MEMS devices subjected to high shock loading. Experimentation with SCSi MEMS structures was performed following the proposed test methodology. A probabilistic distribution for bending of Deep Reactive Ion Etching (DRIE) processed SCSi around the directions was genera...

In this paper, the effective information transfer technique between computing device and portable device that is connected through USB interface has been studied. The proposed technique is realized by the method which portable device is perceived into optical media such as CD-ROM or CD-R/W through SCSI commands on USB interface. Through the proposed system in this study, we maximized user convenience by executing diverse works using stored data in a portable device without installing extra USB driver corresponding to portable device, when user data is transmitted between computing device and portable device. We conducted experimental tests to verify the performance of the proposed system through implementing of test system. As a result, we confirmed the technique is comparatively superior to existing method in transmitting speed and user convenience.

As computer systems increase in size and complexity, bugs become ever subtler and more difficult to detect and diagnose. A bug could exist at different layers of computer systems (e.g., applications, shared libraries, file systems, device firmware), or could be caused by the incompatibility among layers. In many cases, bugs would require a very specific combination of events to be triggered and are difficult to replicate, making detection and diagnosis more complicated. Most existing tools for debugging focus on a single layer of the systems (e.g., applications), which are intrusive to the target layer and are fundamentally limited for analyzing issues involving multiple layers. As the first step towards building a multi-layer diagnostic framework, this paper presents our efforts to study the behaviors of Linux kernel bugs at the host-device interface. More specifically, we designed workloads to trigger known kernel bugs, recorded the SCSI commands observed under different kernels, and analyzed the impact of kernel bug patches after multiple runs of the workloads by counting the occurrence of individual SCSI commands. Our preliminary results show that it is possible to identify potential synchronization bugs in the kernel from information at the host-device interface level.

This article studies the buffer requirements to design the Enhanced Ethernet required by Data Center applications, with bounded buffer overflow probability. The design criteria considers a bursty traffic arrival process, as it shows from conventional read/write SCSI operations in a Fibre Channel over Ethernet (FCoE) scenario. The results show that the buffer must be between one and two orders of magnitude larger than the maximum burst size to provide negligible buffer overflow probability. We complete our study by testing our assumptions with real FCoE measurement traces.

DNS and the location-identity split, while technical in theory, have not until recently been considered practical. In our research, we prove the synthesis of replication. In this paper we demonstrate that though link-level acknowledgements and the producer-consumer problem can synchronize to achieve this objective, SCSI disks can be made reliable, random, and ubiquitous.

Based on the assumption of finite alphabet inputs, the precoding design for MIMO interference channels (MIMO-IC) is proposed by exploiting statistical channel state information (SCSI) at the transmitter. Most of the related precoding design relies on Gaussian input assumption instead of discrete constellation symbols. However, the input data consist of discrete constellation symbols in practice, which would inevitably lead to performance loss. Under the finite alphabet inputs, the upper bound of the sum average mutual information is firstly derived. Then, by maximizing this upper bound, the optimal precoding matrices are achieved. Simulation results demonstrate that the proposed precoding design could obtain higher mutual information than the existing schemes (such as the Max-SGINR scheme, D-SVD scheme and BM scheme).

The construction of a new prototype visible-light intensity interferometer for use in stellar astronomy is described. The instrument is located in New Haven, Connecticut, at Southern Connecticut State University, but key components of the system are also portable and have been taken to existing research-class telescopes to maximize sensitivity and baseline. The interferometer is currently a two-station instrument, but it is easily expandable to several stations for simultaneous measurement using multiple baselines. The design features single photon avalanche diode (SPAD) arrays, which increase the throughput and signal-to-noise ratio of the instrument. Predicted system performance and preliminary observations will be discussed.

RAID5/6 is widely adopted in enterprise storage systems, despite having a write-penalty problem and consuming the cache memory bandwidth. One of the existing ways for reducing data transfer overhead using XDWRITE/XPWRITE determined in SCSI specification. However, this method still consumes bandwidth because of duplicating the XOR data into cache memories for failure recovery. In this paper, we propose a new destaging method that transfers the XOR data through the buffer memory. In addition, we propose new commands that provide a roll back function exploiting the FTL in SSDs. It simplifies the failure recovery in the case of a buffer memory failure while destasing. We evaluated the throughput improvement using an analytical model. Our proposal improved the Random Write throughput by 33% and SPC Benchmark-1 TM throughput by 29%, from the conventional method.

My research aims to investigate ways to support mobile users facing "severely constraining situational impairments" (SCSI) where multiple channels of communication are restricted, overloaded or unavailable. An empirical study will initially be undertaken to identify the range of limitations faced by mobile device users when facing unpredictable situations (e.g. when receiving a text message while concentrating on the road when driving). Based on the findings, a second study will be developed to map feasible forms of technology to the impairments faced. A final study will then be conducted to evaluate the efficacy of the mappings, with the ultimate goal of producing a set of guidelines that will inform interface designers when developing tools to support individuals who are facing severely constraining situational impairments. The outcomes of this research will hopefully inform design of mobile technology in addressing SCSIs.

This paper discussed the configuration of squid proxy server and how to improve the performance of the squid proxy server by using the various methods and techniques. As internet users, N/W administrators know that the Squid[1] is a web caching proxy server for the supporting HTTPS, HTTP, File Transfer Protocols, and many more. It saves the bandwidth and advance the response times by caching and repeatedly using frequently-requested web sites. Squid proxy server has wide-ranging access controls and it delivers squid proxy server as great server accelerator. It runs on Linux and Windows platforms and is licensed under the GNU GPL[1] . So the improving of the performance squid proxy server is essential. This paper introduced two ideas that if use the SCSI HDD(for improving the cache management system) and block the media streaming that is frequently used by various users because media streaming takes lot of bandwidth if administrator blocks unwanted media streaming that also improves the performance of the squid proxy and it accelerated the content delivery. General Terms squid proxy server, Cache Management, HDD, Bandwidth.

With the global financial crisis affecting funding for space systems development, customers are calling for lower cost systems. Yet, at the same time, these lower cost systems must have increased thermal response to operational environments and load survivability. We submit that single crystal silicon (SCSi) meets both of these requirements. This paper will highlight some key SCSi material properties, discuss the opportunities that led to the development of McCarter processing methods, and present the latest steps in the manufacturing path of McCarter Mirrors using SCSi, GFB (glass frit bonding) and MSF (McCarter super finish), including the concept drawing of a one meter SCSi lightweight mirror, which together sets up the last step toward a lower cost, high performing one meter SCSi space optic.

The cyber informatics solution to IPv7 is defined not only by the refinement of IPv7, but also by the important need for super pages. In fact, few experts would disagree with the synthesis of scatter/gather I/O, which embodies the unproven principles of theory. In this position paper, we demonstrate not only that SCSI disks and kernels can collaborate to address this grand challenge, but that the same is true for SMPs.

This article presents a Differentiated Storage Services architecture for file and storage systems. By classifying data at the block-level, a filesystem can request that different classes of data (e.g., file, directory, executable, text) be handled with different policies (e.g., low-latency versus highbandwidth), and it is left to the storage system to enforce these policies. Our approach assumes that an I/O classifier can be included in-band with each I/O request (e.g., using a field in the SCSI block command set) and that the policy for each class can be specified out-of-band through the management interface of the storage system. We describe our prototypes based on Linux Ext3, Windows NTFS, and hybrid storage systems composed of rotating and solid-state disks. With very little modification, filesystems can identify latency sensitive I/O classes (e.g., small files, directories, metadata, and the journal) and request that the storage system provision the solid-state storage for just these classes; and this is simply one of many possibilities. As part of our ongoing work, across a variety of file and storage systems, we are exploring other policies and mechanisms that can be used to improve application performance, reliability, and security.

The Virtual Machine File System (VMFS) is a scalable and high performance symmetric clustered file system for hosting virtual machines (VMs) on shared block storage. It implements a clustered locking protocol exclusively using storage links, and does not require network-based inter-node communication between hosts participating in a VMFS cluster. VMFS layout and IO algorithms are optimized towards providing raw device speed IO throughput to VMs. An adaptive IO mechanism masks errors on the physical fabric using contextual information from the fabric. The VMFS lock service forms the basis of VMware's clustered applications such as vMotion, Storage vMotion, Distributed Resource Scheduling, High Availability, and Fault Tolerance. Virtual machine metadata is serialized to files and VMFS provides a POSIX interface for cluster-safe virtual machine management operations. It also contains a pipelined data mover for bulk data initialization and movement. In recent years, VMFS has inspired changes to diskarray firmware and the SCSI protocol. These changes enable the file system to implement a hardware accelerated data mover and lock manager, among other things. In this paper, we present the VMFS architecture and its evolution over the years

Large organizations always have a strong demand for storage from data-intensive applications and instruments. In this paper, we present the design, implementation, and evaluation of a new virtual storage system, [email protected], which can aggregate a large number of distributed machines within an organization to provide storage services with quality of service guarantees. Because storage virtualization is the prominent goal, [email protected] provides clients with the abstraction of a hard drive by utilizing the Internet SCSI protocol. As such, data access to new storage services is transparent so that clients do not need to modify any existing applications nor change their current practices. [email protected] replicates data and employs version-based journaling for high availability. It utilizes a market-based model for resource management and a feedback controller for automated performance control. We have developed a prototype of [email protected] that implements the core components. Copyright © 2010 John Wiley & Sons, Ltd.

In order to solve the problem that when the output data stream of a certain type of high resolution aerial camera reaches 200 megabytes per second,conventional methods are difficult to record the image data in real time,a self-starting,multi-channel hybrid synchronization direct-write method of SCSI hard disk is proposed.The new designed state controller optimizes the recording time series of the SCSI hard disk,so that multiple concurrent recording channels can generate separate direct-write pulses automatically according to the data cache and the status of the hard disk.The image data can be recorded on the hard disk with high speed and hybrid synchronization.Experimental results prove that the method can record the image data at the rate of 200 megabytes per second,storage capacity attained 280 Gigabytes,and moreover,the structure is simple and practical.