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Supervisory control and data acquisition (SCADA) systems are widely used to monitor and control industrial processes. They provide the key functionality of real-time monitoring, logging/archiving, report generation, and automation for smart grid, which is a promising power delivery system for the near future. On the basis of these functionalities, various SCADA architectures, including hardware and software architecture, have been proposed and standardized; however, the most open and expediently growing areas in the smart grid are the infrastructure and technologies for the SCADA communication and security. In this paper, we provide a review for many documented standards in SCADA, and we also review its state-of-the-art communication and security aspects.

Calibration is a process of comparing model results with field data and making the appropriate adjustments so that both results agree. Calibration methods can involve formal optimization methods or manual methods in which the modeler informally examines alternative model parameters. The development of a calibration framework typically involves the following: (1) definition of the model variables, coefficients, and equations; (2) selection of an objective function to measure the quality of the calibration; (3) selection of the set of data to be used for the calibration process; and (4) selection of an optimization/manual scheme for altering the coefficient values in the direction of reducing the objective function. Hydraulic calibration usually involves the modification of system demands, fine-tuning the roughness values of pipes, altering pump operation characteristics, and adjusting other model attributes that affect simulation results, in particular those that have significant uncertainty associated with their values. From the previous steps, it is clear that model calibration is neither unique nor a straightforward technical task. The success of a calibration process depends on the modeler's experience and intuition, as well as on the mathematical model and procedures adopted for the calibration process. This paper provides a summary of the Battle of the Water Calibration Networks (BWCN), the goal of which was to objectively compare the solutions of different approaches to the calibration of water distribution systems through application to a real water distribution system. Fourteen teams from academia, water utilities, and private consultants participated. The BWCN outcomes were presented and assessed at the 12th Water Distribution Systems Analysis conference in Tucson, Arizona, in September 2010. This manuscript summarizes the BWCN exercise and suggests future research directions for the calibration of water distribution systems.

Smart grid is a promising power infrastructure that is integrated with communication and information technologies. Nevertheless, privacy and security concerns arise simultaneously. Failure to address these issues will hinder the modernization of the existing power system. After critically reviewing the current status of smart grid deployment and its key cyber security concerns, the authors argue that accountability mechanisms should be involved in smart grid designs. We design two separate accountable communication protocols using the proposed architecture with certain reasonable assumptions under both home area network and neighborhood area network. Analysis and simulation results indicate that the design works well, and it may cause all power loads to become accountable. Index Terms-Accountability, advanced metering infrastructure (AMI), security, smart grid. I. INTRODUCTION W ITH THE increasing demand for electricity these years, conventional power grids present a number of inefficient and unreliable drawbacks due to out-of-date technologies that were originally designed decades ago. Many nations plan to modernize their current power grids due to events such as voltage sags, overloads, blackouts, large carbon emissions, etc. [22]. Most of these countries believe that it not only requires reliability, scalability, manageability, and extensibility but also should be secure, interoperable, and cost-effective. Such electric infrastructure is referred to as "smart grid." Generally, smart grid is a promising power delivery infrastructure integrated with bidirectional communication technologies which collects and analyzes data captured in near real time, including power consumption, distribution, and transmission [1]. According to these data, the smart grid can provide predictive information and relevant recommendations to all stakeholders, including utilities, suppliers, and consumers, regarding the optimization of their power utilization [1]. By two-way electrical flow, consumers are able to sell their surfeit energy back to utilities [2]. Smart grid is a complex system of systems. Deploying such a system has enormous and far-reaching technical and social benefits. Nevertheless, increased interconnection and integration also introduce cyber vulnerabilities into the grid. Based on experiences gained from developed information Manuscript

Heterogeneous integration through low-temperature die bonding is a promising technique to enable high-performance III-V photodetectors on the silicon nitride (Si3N4) photonic platform. Here we demonstrate InGaAs/InP modified uni-traveling carrier photodiodes on Si3N4 waveguides with 20 nA dark current, 20 GHz bandwidth, and record-high external (internal) responsivities of 0.8 A/W (0.94 A/W) and 0.33 A/W (0.83 A/W) at 1550 nm and 1064 nm, respectively. Open eye diagrams at 40 Gbit/s are demonstrated. Balanced photodiodes of this type reach 10 GHz bandwidth with over 40 dB common mode rejection ratio.