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Code and data associated with the manuscript, "Temporal Summation and Adaptation in Human Visual Cortex", by Jingyang Zhou, Noah Benson, Kendrick Kay, and Jonathan Winawer

Accurate assessment of a project's progress enables managers to control and manage costs and schedule. Automating the processes to monitor and inspect the progress of works in construction, and ensure that the data acquired and retrieved are able to produce an accurate ‘as-built’ model is an issue that has received ubiquitous attention in the literature. Emphasis has been placed on utilizing technologies such as mobile augmented reality, laser scanners, and computer visions to monitor and control physical objects that possess geometrical properties. Connected systems such as Electrical, Instrumentation and Control Systems (EICS), however, do not possess geometrical properties and as a result have been overlooked, receiving limited attention. This paper utilizes a digital System Information Model (SIM) to enable a project control system based on human-machine interactions, to be developed, in order to monitor progress during the construction of connected systems. By incorporating the design, schedules, activities, and tasks into a digital, cloud-based model, the system enables different parties involved in a project to synchronously work together. Information can be recorded, distributed and shared in real-time therefore significantly improving decision-making, the approvals process, and management of information. A SIM is discipline-specific and there is a need to ensure its interoperability with building information modeling software. Therefore, a bi-directional link between the SIM and the project's overall schedule and three-dimensional model needs to be developed in the future.

Recently, extensive attention has been devoted to eco-city theoretical research in China. Several findings and viewpoints are presented on the various perspectives explored by scholars in this area. However, insufficient efforts have been made to outline the framework because conflicting opinions exist regarding eco-city development. With the purpose of promoting the development of eco-city theory and defining the new research frontier in the field, current existing research outputs were analyzed and induced. A total number of 405 articles focusing on eco-city published in the Chinese Social Sciences Citation Index between 1999 and 2016 were analyzed with a scientific visualization method using Citespace III software. This paper mainly focuses on author co-citation network, document co-citation network, keyword co-occurrence network and term burstiness. Visualized analysis of the literature provides a review of current research to identify the development of new emerging trends. According to these studies, the primary knowledge clusters of China’s eco-city research are system construction, environmental economy, complex community, construction approach, spatial structure, evaluation index and eco-city. Node documents in these clusters are concerned with foundational knowledge of eco-city studies. It is also noted that topics of eco-city research in China are generalized into three core paths, which are eco-city evolution, low-carbon city theory evolution and sustainable development theory evolution. Our research concludes that macro comprehensive studies have become gradually regional, characteristic, and specified. A low-carbon city evaluation system and a low-carbon developing strategy are at the forefront of current research.

Sorting is a classic problem in computer science. Different kinds of sorting algorithms are required in different application scenarios. With regard to the real-time data processing applications implemented on FPGA, a faster throughput and more resource efficient sorting algorithm is needed to complete the data sorting. And the pipelined implementation of sorting algorithm is essential for improving the overall throughput. In this paper, a serial comparison based iterative sort algorithm is proposed and its implementation on FPGA is elaborated. To take advantages of the parallel characteristics of FPGA, the pipelined sorting module is realized by concatenating multiple serial comparison sorting submodules. Compared to other sorting algorithms implemented on FPGA, the serial comparison based iterative sort algorithm has the merit of requiring fewer resource consumptions, consuming less executing time and generating faster overall data throughput. The algorithm and its pipelined implementation have been successfully applied to the median filter of OS-CFAR processing in millimetre-wave MIMO radar, and their performance have been validated.

Identifying potential hazards of construction project is a data-intensive process that involves various types of information such as site data, specifications, and engineering documents. Ho...

The evaluation and optimization of the carrying capacity of urban resources and environment is an important basis for sustainable development of cities and society. The change of urban space scale indicates that serious unbalance crisis of urban space distribution is hidden behind the rapid development. This paper aims to provide a brand-new way for meeting the unbalance characteristics when evaluating carrying capacity of resource and environment. Firstly, an analysis on the unbalance characteristics of urban development was conducted for providing a foundation for this research. Secondly, the thought of urban grid and finite element analysis were introduced to this study. As a result, a conceptual framework was designed for evaluating resources and environment carrying capacity (RECC) under the unbalance condition. This conceptual framework includes four steps, which are construction of basic database, the division of urban grid and the mechanical analysis of RECC, finite element analysis of urban unit grid, and integration of RECC. A detailed introduction of the whole process was provided. The research results will provide an innovative idea for the evaluation of urban RECCs. It can also inspire urban managers to proceed from the status quo and make full use of urban resource and environmental systems.

Quality of CAD generated 'As-built' documentation is evaluated for a High Voltage Switchgear System.CAD drawings are used to create a Systems Information Model.Significant errors, omissions and information redundancy identified in the CAD drawings.CAD drawings took 10,680 man-h to develop compared to 80 man-h required to construct a SIM.A SIM should be to design and document electrical control instrumentation systems. The quality of computer-aided-design (CAD) generated 'As-built' documentation is evaluated for a High Voltage Switchgear System (HVSS), which forms part of a Supervisory Control and Data Acquisition up-grade within a geo-thermal power plant. A total of 267 CAD drawings for the HVSS were used to create a Systems Information Model (SIM) whereby the physical components and associated connections were constructed in an object orientated database. Throughout the modelling process a considerable amount of errors and information redundancy were identified and examples are presented. The production of the CAD drawings took 10,680 man-h in stark contrast to the 80 man-h required to construct the SIM, illustrating the efficiency and effectiveness of SIM compared to CAD for the documentation of electrical instrumentation and control systems (EICS). To realise this significant potential cost and productivity saving requires a shift in mindset and a move beyond the use of CAD, to an object oriented SIM, with a 1:1 relationship between objects in the model, and components in the real world.

The mining industry in Australia is in a period of intense introspection as it seeks to improve its productivity and competitiveness in global markets. With mining projects experiencing increasing overruns on capital expenditure, there is a need to re-examine existing business practices to address the prevailing productivity crisis that the industry is experiencing. In addressing this issue, within the context of electrical instrumentation and control systems (EICS), a case study that examines the development of a systems information model (SIM) to improve productivity during the engineering, construction, maintenance, and operations processes of a magnetite iron ore processing plant is presented and discussed. By transforming the established document oriented information exchanges that are typically used in EICS projects to a more collaborative data-sharing environment, processes were streamlined and errors, as a result of duplication and inconsistency, were significantly prevented from occurring. While still working within the restriction of discipline-specific models, the creation of a SIM is the first step towards an integrated and interoperable data without a reliance on drawings.

As the creators of the external benefits of prefabricated construction implementation, the government, real estate developers, and homebuyers have the right to allocate the external benefits. However, there is no effective quantitative method for achieving this goal. Therefore, this study aims to develop a quantitative analysis model for the reasonable allocation of the external benefits among the creators. The externality theory and bargaining theory were introduced to this study as the research foundation. Through literature review, the environmental benefit quantification index was defined. A bargaining model including Game 1 and Game 2 was designed for determining the external benefits allocation ratios for each player. In Game 1, the government was considered as the agent of homebuyers to conduct the bargaining game with real estate developers. Game 2 reflected the bargaining game process between the government and homebuyers for sharing the ratio of external benefits achieved from Game 1. The powerful position in bargaining game and discount factors of each player were considered as the critical factors influencing the distribution ratio because the value will change with the development of prefabricated construction. A prefabricated construction building was selected as a case to illustrate the applicability of this proposed model. The distribution result is that the government, the real estate developers, and homebuyers should share the external benefits of prefabrication implementation by 38%, 35%, and 27% respectively. This study contributes to aiding the creators to achieve optimal benefits allocation and thus motivates the enthusiasm of practitioners in prefabricated construction implementation.

Purpose – The purpose of this paper is to determine the unproductive time and additional cost to re-engineer a safety control system for a Floating Production Storage Offloading vessel that was originally engineered and documented in computer-aided design (CAD). Design/methodology/approach – The “As-Built” drawings contained numerous errors and omissions, which resulted in a “requests for information” being raised and productivity rates reduced – these costs and productivity losses are quantified. The use of CAD to originally engineer and document the safety control system was found to be inefficient as a 1:n relationship existed. Systems Information Models (SIMs) presents an alternative method to produce engineering documentation for the safety control system; where a 1:1 relationship is created between the model and the real objects. By constructing a 1:1 model, information redundancy can be eliminated, which reduces the propensity for errors and omissions to be made by engineers. Findings – The use of a SIM to re-engineer and document the new safety control system resulted in significant productivity benefits being achieved. Consequently, it is proffered that a paradigm shift from a 1:n to 1:1 perspective is required for engineering electrical and instrumentation systems so as to ameliorate the quality of documentation produced and productivity. Originality/value – The paper concludes by suggesting that future research is required to examine how processes and procedures can be re-designed to accommodate the use of a SIM.

Although urbanization can promote social and economic development, it can also cause various problems. As the key decision makers of urbanization, local governments should be able to evaluate urbanization performance, summarize experiences, and find problems caused by urbanization. This paper introduces a hybrid Entropy–McKinsey Matrix method for evaluating sustainable urbanization. The McKinsey Matrix is commonly referred to as the GE Matrix. The values of a development index (DI) and coordination index (CI) are calculated by employing the Entropy method and are used as a basis for constructing a GE Matrix. The matrix can assist in assessing sustainable urbanization performance by locating the urbanization state point. A case study of the city of Jinan in China demonstrates the process of using the evaluation method. The case study reveals that the method is an effective tool in helping policy makers understand the performance of urban sustainability and therefore formulate suitable strategies for guiding urbanization toward better sustainability.

Combining sensory inputs over space and time is fundamental to vision. Population receptive field models have been successful in characterizing spatial encoding throughout the human visual pathways. A parallel question—how visual areas in the human brain process information distributed over time—has received less attention. One challenge is that the most widely used neuroimaging method—fMRI—has coarse temporal resolution compared to the time-scale of neural dynamics. Here, via carefully controlled temporally modulated stimuli, we show that information about temporal processing can be readily derived from fMRI signal amplitudes in male and female subjects. We find that all visual areas exhibit sub-additive summation, whereby responses to longer stimuli are less than the linear prediction from briefer stimuli. We also find fMRI evidence that the neural response to two stimuli is reduced for brief interstimulus intervals (indicating adaptation). These effects are more pronounced in visual areas anterior to V1-V3. Finally, we develop a general model that shows how these effects can be captured with two simple operations: temporal summation followed by a compressive nonlinearity. This model operates for arbitrary temporal stimulation patterns and provides a simple and interpretable set of computations that can be used to characterize neural response properties across the visual hierarchy. Importantly, compressive temporal summation directly parallels earlier findings of compressive spatial summation in visual cortex describing responses to stimuli distributed across space. This indicates that for space and time, cortex uses a similar processing strategy to achieve higher-level and increasingly invariant representations of the visual world.Significance statementCombining sensory inputs over time is fundamental to seeing. Two important temporal phenomena are summation, the accumulation of sensory inputs over time, and adaptation, a response reduction for repeated or sustained stimuli. We investigated these phenomena in the human visual system using fMRI. We built predictive models that operate on arbitrary temporal patterns of stimulation using two simple computations: temporal summation followed by a compressive nonlinearity. Our new temporal compressive summation model captures (1) subadditive temporal summation, and (2) adaptation. We show that the model accounts for systematic differences in these phenomena across visual areas. Finally, we show that for space and time, the visual system uses a similar strategy to achieve increasingly invariant representations of the visual world.

Electrical instrumentation and control (EIC) systems can account for as much as 60% of maintainable items as well as being critical to safe and efficient operations. Thus, it is imperative that as-built documentation is error-free and reflects precisely what has been installed. Yet EIC as-built drawings that are produced often contain errors and omissions. If EIC systems are ineffectively and inefficiently designed and documented, then asset owners' plant, equipment and facilities may fail to operate, which can result in considerable economic loss and jeopardize system safety. In order to improve the quality, efficiency and effectiveness of documentation production, it has been suggested that engineers should switch from using computer-aided design (CAD) to an object-oriented model, which takes the form of a systems information model. Such a model provides the ability for electrical engineers to effectively integrate their work with a building information model. This paper builds upon the authors' previous research, which examined the need for a SIM by presenting and describing how an object-oriented model for EIC can be used through a project's life cycle. Examples are used to demonstrate the functionality and robustness of the SIM. The adoption of a SIM will not only lead to productivity throughout a project's life but also reduce the costs associated with managing and maintaining information.

In order to solve the phase-coded signal Doppler sensitive problem, the Doppler search algorithm based on frequency domain is often used. However, in tracking and measuring radar, the traditional algorithm is difficult to meet the requirements due to the requirement of target measurement accuracy and real-time signal processing. This paper focuses on the 13 bit Barker code signal, based on the analysis of the characteristics of the Barker code signal, completes the high precision Doppler compensation of the single pulse signal under the CPU+GPU software platform using a Doppler compensation algorithm based on time-domain. At the same time, combined with classical tracking radar algorithm, effectively improve the real-time signal processing. Completed the phase code on the target of precision measurement and tracking.

Visual neurons respond to static images with specific dynamics: neuronal responses sum sub-additively over time, reduce in amplitude with repeated or sustained stimuli (neuronal adaptation), and are slower at low stimulus contrast. Here, we propose a simple model that predicts these seemingly disparate response patterns observed in a diverse set of measurements–intracranial electrodes in patients, fMRI, and macaque single unit spiking. The model takes a time-varying contrast time course of a stimulus as input, and produces predicted neuronal dynamics as output. Model computation consists of linear filtering, expansive exponentiation, and a divisive gain control. The gain control signal relates to but is slower than the linear signal, and this delay is critical in giving rise to predictions matched to the observed dynamics. Our model is simpler than previously proposed related models, and fitting the model to intracranial EEG data uncovers two regularities across human visual field maps: estimated linear filters (temporal receptive fields) systematically differ across and within visual field maps, and later areas exhibit more rapid and substantial gain control. The model is further generalizable to account for dynamics of contrast-dependent spike rates in macaque V1, and amplitudes of fMRI BOLD in human V1., Author summary This paper contributes to modeling and understanding the neuronal dynamics of visual cortex in four ways. First, we proposed a model that describes stimulus-driven neuronal dynamics in a simple and intuitive way. Second, we applied the model to intracranial EEG data and found regularities of response dynamics across and within human visual field maps. Third, the model was generalizable across different ways of measuring brain activity, allowing us to potentially link the sources underlying diverse measurements. Fourth, we comprehensively summarized existing models of neuronal dynamics, and identified effective components that give rise to accurate prediction.

The construction of rural residential buildings has a great impact on the achievement of sustainable countryside. It needs a cleaner construction method. This study argues that prefabrication should be adopted in rural areas, but different strategies should be designed based on the strengths, weaknesses, opportunities, and threats (SWOT). This issue has not been involved in previous studies. This paper aims to design a model for determining the suitable strategy of prefabrication implementation. Twelve factors affecting the prefabrication implementation were firstly identified for SWOT analysis, including prefabricated construction standards, ecological benefits, transportation capacity, and so on. A strategy selection model expressed by strategic vector (θ, ρ) was then designed, in which strategic azimuth (θ) determines the strategy type and intensity coefficient (ρ) determines the attitudes that should be taken to the selected strategy. Four types of strategies (aggressing, pioneering, reverse, and avoidant) and two development intensities (conservative and proactive) were summarized. The model was substantiated in a village of Jinan as a case. It was identified that aggressing strategy with conservative attitude is the optimal strategy to the current conditions in rural Jinan. The developed model can be adopted by other rural areas for devising their suitable prefabrication development strategies.

Documentation errors have been identified as a significant problem within the construction and engineering industry. Errors contained with contract documents can contribute to loss of profit, reduced productivity, and cost and time overruns as well as contractual disputes. Research has identified that as much as 60% of variations in construction and engineering projects are a result of errors and omissions contained within poor quality documentation. Considering this alarming statistic and the impact that poor quality documentation can have on productivity, the research presented in this paper classifies and quantifies errors in 106 drawings and the cable schedule used to document for the electrical package for an Iron Ore Stacker Conveyor. The research reveals that Computer Aided Design (CAD) used to produce the electrical drawings was ineffective, inefficient and costly to produce as they contained an array of errors. In addressing the need to eliminate documentation errors and improve productivity, the cable schedule is used to create a Systems Information Management to develop a 1:1 object orientated model using the software Dynamic Asset Documentation. As a result, of using this approach it is estimated that a 94% cost saving and a substantial improvement in productivity could have been attained in this particular case.

Optimizing construction project scheduling has received a considerable amount of attention over the past 20 years. As a result, a plethora of methods and algorithms have been developed to address specific scenarios or problems. A review of the methods and algorithms that have been developed to examine the area of construction schedule optimization (CSO) is undertaken. The developed algorithms for solving the CSO problem can be classified into three methods: mathematical, heuristic and metaheuristic. The application of these methods to various scheduling problems is discussed and implications for future research are identified.

Mobile agent has shown its promise as a powerful means to complement and enhance existing technology in various application areas. In particular, existing work has demonstrated that MA can simplify the development and improve the performance of certain classes of distributed applications, especially for those running on a wide-area, heterogeneous, and dynamic networking environment like the Internet. In our previous work, we extended the application of MA to the design of distributed control functions, which require the maintenance of logical relationship among and/or coordination of proc- essing entities in a distributed system. A novel framework is presented for structuring and building distributed systems, which use cooperating mobile agents as an aid to carry out coordination and cooperation tasks in distributed systems. The framework has been used for designing various distributed control functions such as load balancing and mutual ex- clusion in our previous work. In this paper, we use the framework to propose a novel ap- proach to detecting deadlocks in distributed system by using mobile agents, which dem- onstrates the advantage of being adaptive and flexible of mobile agents. We first describe the MAEDD (Mobile Agent Enabled Deadlock Detection) scheme, in which mobile agents are dispatched to collect and analyze deadlock information distributed across the network sites and, based on the analysis, to detect and resolve deadlocks. Then the design of an adaptive hybrid algorithm derived from the framework is presented. The algorithm can dynamically adapt itself to the changes in system state by using different deadlock detec- tion strategies. The performance of the proposed algorithm has been evaluated using simulations. The results show that the algorithm can outperform existing algorithms that use a fixed deadlock detection strategy.

A fundamental problem in a pure Peer-to-Peer (P2P) file sharing system is how to protect the anonymity of peer nodes when providing efficient data access services. Most of existing work mainly focus on how to provide the initiator anonymity, but neglect the anonymity of the responder. In this paper, we propose a multicast-based protocol, called Mapper, for efficient file sharing with mutual anonymity. By seamlessly combining the technologies of multi-proxy and IP multicast together, the proposed protocol guarantees mutual anonymity during the entire session of file retrieval. Furthermore, Mapper replicates requested files inside the multicast group, so file distribution can be adjusted adaptively and the cost for multicast can be further reduced. Results of both simulations and theoretical analyses demonstrate that Mapper possesses the merits of scalability, reliability, and high adaptability.

Generation schedule has a great impact on the economic operation of power grid. However, the characteristics of unable to accurately prediction and strong volatility make wind power generation different from regular units when scheduling. Based on this, this paper reviews the methods of day-ahead or intraday generation schedule with integration of wind power. Then, evaluations and potential improvements on each method are given. Additionally, wind power dispatch in Gansu power grid, China is simply described and evaluation is given.

Simulation has been proved to be a practical approach for performance evaluation of mobile agents. However, the lack of a standard for the execution of mobile agents makes the semantics ambiguous. Thus, the simulation of mobile agents is not feasible or reasonable without an explicitly defined execution model of agents. In this paper, we propose an execution model of mobile agents called SMA. Based on the SMA model, the discrete event models describing the SMA agents and hosts, called SMA-DEVS, are presented using the modelling approach of DEVS and DSDE. We implement a simulation environment based on SMA-DEVS and test the environment with certain mobile agent-based algorithms.

Deadlock detection and resolution are of the fundamental issues in distributed systems. Although many algorithms have been proposed, these message passing based traditional solutions can hardly meet the challenges of the prevailing Internet computing and mobile computing. In this paper, we present a novel algorithm, namely the M-Guard, for deadlock detection and resolution in distributed systems based on mobile agent technology. The proposed algorithm lies in the intersection of the centralized type algorithm and the distributed type algorithm. An agent is employed in our algorithm as a guard with dual-role: when roaming in the system according to a specified itinerary algorithm, the agent collects resource request/allocation information for detecting deadlock cycles as well as propagating the collected network and resource information among the nodes. Consequently, accurate and timely detections of deadlocks can be made without any network node being the performance bottleneck. Preliminary simulation results show that, compared with several other algorithms, the M-Guard algorithm achieves both shorter deadlock persisting time and smaller phantom deadlock ratio. Moreover, the overall network communication overhead can be decreased, too.

A novel framework, called MAEDD (Mobile Agent Enabled Deadlock Detection), for distributed deadlock detection using mobile agents is proposed. In MAEDD, mobile agents are dispatched to collect and analyze deadlock information distributed over the network sites, detect deadlock cycles in the system, and then resolve the deadlocks. A prototype implementing the proposed framework is developed using IBM’s Aglets. The performance of our mobile agent enabled approach is evaluated against traditional message-passing based solutions. Preliminary performance evaluation results indicate that MAEDD can detect deadlock faster than massage-passing solutions, with increased network traffic.

A fundamental problem in a pure Peer-to-Peer (P2P) file sharing system is how to protect the anonymity of nodes when providing efficient data access services. By seamlessly combining the technologies of multi-proxy and IP multicast together, we propose a multicast-based protocol for efficient file sharing with mutual anonymity in this paper. Furthermore, the proposed protocol can adaptively adjust file distribution and reduce the multicast cost simultaneously. The simulations show that Mapper possesses the merits of scalability, reliability, and high adaptability with high performance.

Summary form only given. Many algorithms for achieving mutual exclusion in distributed computing systems have been proposed. The three most often used performance measures are the number of messages exchanged between the nodes per critical section (CS) execution, the response time, and the synchronization delay. We present a new fully distributed mutual exclusion algorithm. A node requesting the CS sends out the request message which will roam in the network. The message are forwarded among the nodes until the requesting node obtains enough permissions to decide its order to enter the CS. The decision is made by using relative consensus voting (RCV), which is a variation of the well-known majority consensus voting (MCV) scheme. Unlike existing algorithms which determine the node to enter the CS one by one, in our algorithm, several nodes can be decided and ordered for executing the CS. The synchronization delay is minimal. Although the message complexity can be up to O(N) in the worst case in a system with N nodes, our simulation results show that, on average, the algorithm needs less number of messages and has less response time than most of those existing algorithms which do not require a logical topology imposed on the nodes. This is especially true when the system is under heavy demand. Another feature of the proposed algorithm is that it does not require the FIFO property of the underlying message passing mechanism.