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1.
Sensors (Basel) ; 22(11)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35684808

RESUMO

Product defect inspections are extremely important for industrial manufacturing processes. It is necessary to develop a special inspection system for each industrial product due to their complexity and diversity. Even though high-precision 3D cameras are usually used to acquire data to inspect 3D objects, it is hard to use them in real-time defect inspection systems due to their high price and long processing time. To address these problems, we propose a product inspection system that uses five 2D cameras to capture all inspection parts of the product and a deep learning-based 2D convolutional neural network (CNN) with spatial and channel attention (SCA) mechanisms to efficiently inspect 3D ball joint socket products. Channel attention (CA) in our model detects the most relevant feature maps while spatial attention (SA) finds the most important regions in the extracted feature map of the target. To build the final SCA feature vector, we concatenated the learned feature vectors of CA and SA because they complement each other. Thus, our proposed CNN with SCA provides high inspection accuracy as well as it having the potential to detect small defects of the product. Our proposed model achieved 98% classification accuracy in the experiments and proved its efficiency on product inspection in real-time.


Assuntos
Articulações , Redes Neurais de Computação , Atenção , Comércio , Sistemas Computacionais
2.
Sensors (Basel) ; 22(11)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35684924

RESUMO

Complete traffic sensor data is a significant prerequisite for analyzing the changing rules of traffic flow and formulating traffic control strategies. Nevertheless, the missing traffic data are common in practice. In this study, an improved Fuzzy C-Means algorithm is proposed to repair missing traffic data, and three different repair modes are established according to the correlation of time, space, and attribute value of traffic flow. First, a Twice Grid Optimization (TGO) algorithm is proposed to provide a reliable initial clustering center for the FCM algorithm. Then the Sparrow Search Algorithm (SSA) is used to optimize the fuzzy weighting index m and classification number k of the FCM algorithm. Finally, an experimental test of the traffic sensor data in Shunyi District, Beijing, is employed to verify the effectiveness of the TGO-SSA-FCM. Experimental results showed that the improved algorithm had a better performance than some traditional algorithms, and different data repair modes should be selected under different miss rate conditions.


Assuntos
Algoritmos , Sistemas Computacionais , Análise por Conglomerados
3.
Stud Health Technol Inform ; 290: 1006-1007, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35673178

RESUMO

This pilot study examines the similarities and differences between treatment recommendations offered by a decision system and trained tobacco treatment specialists. Using a sample of ten de-identified patient cases who used tobacco, we compared recommendations from the manual and preliminary review of cases by four tobacco specialists with the automated analysis of patient cases using both the first version of the rule-based system and the second version with improved and additional rules.


Assuntos
Sistemas Computacionais , Tabaco , Computadores , Humanos , Projetos Piloto , Uso de Tabaco
4.
Comput Intell Neurosci ; 2022: 5354326, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720941

RESUMO

Multihop smart grid is built on the basis of an integrated and high-speed communication network. Through the application of advanced sensing and measurement technology, equipment technology, control method, and advanced decision support system technology, the goal of reliable, safe, economic, efficient, environment-friendly, and safe use of the power grid is realized. In order to solve the problem of excessive demand for power supply, new energy power generation and demand response are proposed. According to the above background, the demand side economic scheduling problem is a complex optimization problem, which is difficult to be solved by ordinary algorithms. The adaptive global search algorithm based on a genetic algorithm can better solve complex optimization problems. The genetic algorithm proposed in this paper can effectively manage a large number of controllable loads in the selected area. The algorithm minimizes the cost and peak to the average ratio by changing the load. Home users can arrange their maximum load when the price is low. The peak load of residential buildings decreased from 98.5 kw/h to 90 kw/h, and the peak load decreased by about 7.53%. Through appropriate load dispatching, users minimize the daily electricity charge, which is reduced from 1352 yuan to 1245 yuan per day, and the daily electricity charge is reduced by about 7.25%. In addition, the advanced measurement, communication, and control means under the framework of the smart grid also play a key role in promoting all aspects of demand side management (DSM).


Assuntos
Algoritmos , Eletricidade , Sistemas Computacionais , Fontes de Energia Elétrica , Tecnologia
5.
Comput Intell Neurosci ; 2022: 4033886, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35707190

RESUMO

Through the information exchange of the Internet of Things, resources in multiple fields can be integrated to provide users with more comprehensive, diverse, and high-quality services. The computer monitoring system can effectively improve the intelligence and networking of the office and is widely used in many industries. The application of Internet of Things technology can effectively improve the intelligence and networking of computer monitoring systems. The Internet of Things technology can realize the interaction between things and people, help the computer monitoring system to obtain the required information, and truly realize comprehensive monitoring. Based on this, this paper first introduces the basic technology of the Internet of Things technology and analyzes the main points of the computer monitoring technology based on the Internet of Things at this stage and then takes a computer monitoring system as the research object, and further analyzes the computer monitoring system based on the Internet of Things technology to help relevant personnel better apply IoT technology to computer monitoring systems.


Assuntos
Tecnologia , Tecnologia sem Fio , Sistemas Computacionais , Computadores , Humanos , Internet
6.
Sensors (Basel) ; 22(10)2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35632175

RESUMO

Recently, the number of users and the demand for live-streaming services have increased. This has exponentially increased the traffic to such services, and live-streaming service platforms in Korea use a grid computing system that distributes traffic to users and reduces traffic loads. However, ensuring security with a grid computing system is difficult because the system exchanges general user traffic in a peer-to-peer (P2P) manner instead of receiving data from an authenticated server. Therefore, in this study, to explore the vulnerabilities of a grid computing system, we investigated a vulnerability discovery framework that involves a three-step analysis process and eight detailed activities. Four types of zero-day vulnerabilities, namely video stealing, information disclosure, denial of service, and remote code execution, were derived by analyzing a live-streaming platform in Korea, as a representative service, using grid computing.


Assuntos
Sistemas Computacionais , Computadores , República da Coreia
7.
Sensors (Basel) ; 22(10)2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35632314

RESUMO

A low-cost and power-efficient video surveillance system, named XDMOM, is developed for real-time moving object detection outdoors or in the wild. The novel system comprises four parts: imaging subsystem, video processing unit, power supply, and alarm device. The imaging subsystem, which consists of a dual-spectrum camera and rotary platform, can realize 360-degree and all-day monitoring. The video processing unit uses a power-efficient NVIDIA GeForce GT1030 chip as the processor, which ensures the power consumption of the whole system maintains a low level of 60~70 W during work. A portable lithium battery is employed to supply power so that the novel system can be used anywhere. The work principle is also studied in detail. Once videos are recorded, the single-stage neural network YOLOv4-tiny is employed to detect objects in a single frame, and an adaptive weighted moving pipeline filter is developed to remove pseudo-targets in the time domain, thereby reducing false alarms. Experimental results show that the overall correct alarm rate of the novel system could reach 85.17% in the daytime and 81.79% at night when humans are monitored in real outdoor environments. The good performance of the novel system is demonstrated by comparison with state-of-the-art video surveillance systems.


Assuntos
Algoritmos , Sistemas Computacionais , Humanos , Monitorização Fisiológica , Redes Neurais de Computação
8.
Comput Intell Neurosci ; 2022: 5800183, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35510047

RESUMO

CAD technology has brought great convenience and effect to the design. This paper proposes to update the comparative analysis of the basic classical landscape grid space structure by constructing a landscape grid space design. According to the actual situation of domestic landscape grid space design and drawing, this paper highlights the role of CAD technology in landscape grid space design and drawing and provides an important basis for the subsequent application of CAD software in landscape grid space design.


Assuntos
Sistemas Computacionais , Software
9.
Nat Neurosci ; 25(5): 531, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35524135
10.
Sensors (Basel) ; 22(9)2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35590987

RESUMO

The original concept of the artificial potential field in robot path planning has spawned a variety of extensions to address its main weakness, namely the formation of local minima in which the robot may be trapped. In this paper, a smooth navigation function combining the Dijkstra-based discrete static potential field evaluation with bilinear interpolation is proposed. The necessary modifications of the bilinear interpolation method are developed to make it applicable to the path-planning application. The effect is that the strategy makes it possible to solve the problem of the local minima, to generate smooth paths with moderate computational complexity, and at the same time, to largely preserve the product of the computationally intensive static plan. To cope with detected changes in the environment, a simple planning strategy is applied, bypassing the static plan with the solution of the A* algorithm to cope with dynamic discoveries. Results from several test environments are presented to illustrate the advantages of the developed navigation model.


Assuntos
Robótica , Algoritmos , Sistemas Computacionais , Robótica/métodos , Tempo
11.
PLoS One ; 17(4): e0266439, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35385516

RESUMO

The gender gap in computer science (CS) research is a well-studied problem, with an estimated ratio of 15%-30% women researchers. However, far less is known about gender representation in specific fields within CS. Here, we investigate the gender gap in one large field, computer systems. To this end, we collected data from 72 leading peer-reviewed CS conferences, totalling 6,949 accepted papers and 19,829 unique authors (2,946 women, 16,307 men, the rest unknown). We combined these data with external demographic and bibliometric data to evaluate the ratio of women authors and the factors that might affect this ratio. Our main findings are that women represent only about 10% of systems researchers, and that this ratio is not associated with various conference factors such as size, prestige, double-blind reviewing, and inclusivity policies. Author research experience also does not significantly affect this ratio, although author country and work sector do. The 10% ratio of women authors is significantly lower than the 16% in the rest of CS. Our findings suggest that focusing on inclusivity policies alone cannot address this large gap. Increasing women's participation in systems research will require addressing the systemic causes of their exclusion, which are even more pronounced in systems than in the rest of CS.


Assuntos
Bibliometria , Pesquisadores , Sistemas Computacionais , Feminino , Humanos , Masculino
12.
Sensors (Basel) ; 22(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35458910

RESUMO

Cloud-induced photovoltaic variability can affect grid stability and power quality, especially in electricity systems with high penetration levels. The availability of irradiance field forecasts in the scale of seconds and meters is fundamental for an adequate control of photovoltaic systems in order to minimize their impact on distribution networks. Irradiance sensor networks have proved to be efficient tools for supporting these forecasts, but the costs of monitoring systems with the required specifications are economically justified only for large plants and research purposes. This study deals with the design and test of a wireless irradiance sensor network as an adaptable operational solution for photovoltaic systems capable of meeting the measurement specifications necessary for capturing the clouds passage. The network was based on WiFi, comprised 16 pyranometers, and proved to be stable at sampling periods up to 25 ms, providing detailed spatial representations of the irradiance field and its evolution. As a result, the developed network was capable of achieving comparable specifications to research wired irradiance monitoring network with the advantages in costs and flexibility of the wireless technology, thus constituting a valuable tool for supporting nowcasting systems for photovoltaic management and control.


Assuntos
Sistemas Computacionais , Tecnologia sem Fio , Computadores , Eletricidade
13.
Sensors (Basel) ; 22(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35458991

RESUMO

Real-time biomechanical feedback (BMF) is a relatively new area of research. The potential of using advanced technology to improve motion skills in sport and accelerate physical rehabilitation has been demonstrated in a number of studies. This paper provides a literature review of BMF systems in sports and rehabilitation. Our motivation was to examine the history of the field to capture its evolution over time, particularly how technologies are used and implemented in BMF systems, and to identify the most recent studies showing novel solutions and remarkable implementations. We searched for papers in three research databases: Scopus, Web of Science, and PubMed. The initial search yielded 1167 unique papers. After a rigorous and challenging exclusion process, 144 papers were eventually included in this report. We focused on papers describing applications and systems that implement a complete real-time feedback loop, which must include the use of sensors, real-time processing, and concurrent feedback. A number of research questions were raised, and the papers were studied and evaluated accordingly. We identified different types of physical activities, sensors, modalities, actuators, communications, settings and end users. A subset of the included papers, showing the most perspectives, was reviewed in depth to highlight and present their innovative research approaches and techniques. Real-time BMF has great potential in many areas. In recent years, sensors have been the main focus of these studies, but new types of processing devices, methods, and algorithms, actuators, and communication technologies and protocols will be explored in more depth in the future. This paper presents a broad insight into the field of BMF.


Assuntos
Sistemas Computacionais , Esportes , Exercício Físico , Retroalimentação , Tecnologia
14.
Sensors (Basel) ; 22(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408082

RESUMO

The Azure Kinect represents the latest generation of Microsoft Kinect depth cameras. Of interest in this article is the depth and spatial accuracy of the Azure Kinect and how it compares to its predecessor, the Kinect v2. In one experiment, the two sensors are used to capture a planar whiteboard at 15 locations in a grid pattern with laser scanner data serving as ground truth. A set of histograms reveals the temporal-based random depth error inherent in each Kinect. Additionally, a two-dimensional cone of accuracy illustrates the systematic spatial error. At distances greater than 2.5 m, we find the Azure Kinect to have improved accuracy in both spatial and temporal domains as compared to the Kinect v2, while for distances less than 2.5 m, the spatial and temporal accuracies were found to be comparable. In another experiment, we compare the distribution of random depth error between each Kinect sensor by capturing a flat wall across the field of view in horizontal and vertical directions. We find the Azure Kinect to have improved temporal accuracy over the Kinect v2 in the range of 2.5 to 3.5 m for measurements close to the optical axis. The results indicate that the Azure Kinect is a suitable substitute for Kinect v2 in 3D scanning applications.


Assuntos
Sistemas Computacionais , Luz , Fenômenos Biomecânicos
15.
Sensors (Basel) ; 22(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408089

RESUMO

This paper presents a novel solution in the field of the integration of the Smart Grid and the Internet of Things. The definition of a web platform able to offer a RESTful interface to IEC 61850 Servers to a generic user is proposed. The web platform enables the mapping of information maintained by an IEC 61850 Server into MQTT messages. Suitable mechanisms to introduce interoperable exchange of information were defined. The paper presents the main features offered by the proposed platform. The originality of the proposal is highlighted by comparing it with the current literature. A prototype was realized, and the software implementation choices are described and the main results of its evaluation are presented.


Assuntos
Sistemas Computacionais , Tecnologia , Software
16.
Sensors (Basel) ; 22(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35459004

RESUMO

Power line communication (PLC) is considered one of the possible communication technologies for applications in the field of smart metering, smart substations, smart homes, and recently for the management of renewable resources or micro grid control. This article deals with the use of PLC technology to determine the technical condition of the cable. This coefficient can help distribution system operators (DSO) to assess the condition of their cable routes. In this way, possible cable breakdowns and subsequent power outages can be prevented. The resulting methodology for calculating the coefficient is presented in two specific examples of routes, in which a significant benefit for DSO's can be found.


Assuntos
Comunicação , Sistemas Computacionais , Eletricidade
17.
Sensors (Basel) ; 22(6)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35336275

RESUMO

Recent theoretical studies demonstrate the advantages of using decentralized architectures over traditional centralized architectures for real-time Power Distribution Systems (PDSs) operation. These advantages include the reduction of the amount of data to be transmitted and processed when performing state estimation in PDSs. The main contribution of this paper is to provide lab validation of the advantages and feasibility of decentralized monitoring of PDSs. Therefore, this paper presents an advanced trial emulating realistic conditions and hardware setup. More specifically, the paper proposes: (i) The laboratory development and implementation of an Advanced Measurement Infrastructure (AMI) prototype to enable the simulation of a smart grid. To emulate the information traffic between smart meters and distribution operation centers, communication modules, that enable the use of wireless networks for sending messages in real-time, are used, bridging concepts from both IoT and Edge Computing. (ii) The laboratory development and implementation of a decentralized architecture based on Embedded State Estimator Modules (ESEMs) are carried out. ESEMs manage information from smart meters at lower voltage networks, performing real-time state estimation in PDSs. Simulations performed on a real PDS with 208 buses (considering both medium and low voltage buses) have met the aims of this paper. The results show that by using ESEMs in a decentralized architecture, both the data transit through the communication network, as well as the computational requirements involved in monitoring PDSs in real-time, are reduced considerably without any loss of accuracy.


Assuntos
Sistemas Computacionais , Simulação por Computador , Meios de Cultura
18.
Sensors (Basel) ; 22(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35336440

RESUMO

Narrowband power-line communication seems to be a suitable communication technology designed for off-grid renewable energy solutions. Existing electrical installations can be designed both for the transmission of electricity and for the communication of electrical equipment operating inside such an installation. This study presents an implementation of the above-mentioned off-grid communication system and examines the basic problems related to its exploitation. The authors of this article focused their attention primarily on examining the disturbance of the communication channel caused by the use of typical electrical devices, such as: a light bulb, a kettle, etc. used in a household. The aim of the research was also to find the impact of switching on individual devices and their combinations on the disturbances during data transmission. Measurements of incorrectly transmitted data packets were carried out and then the test results were referred to the error measures. Moreover, the influence of the carrier frequencies on the signal attenuation and the method of eliminating the existing interferences were also discussed.


Assuntos
Eletricidade , Energia Renovável , Comunicação , Sistemas Computacionais
19.
Math Biosci Eng ; 19(3): 2403-2423, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-35240790

RESUMO

Demand response programs allow consumers to participate in the operation of a smart electric grid by reducing or shifting their energy consumption, helping to match energy consumption with power supply. This article presents a bio-inspired approach for addressing the problem of colocation datacenters participating in demand response programs in a smart grid. The proposed approach allows the datacenter to negotiate with its tenants by offering monetary rewards in order to meet a demand response event on short notice. The objective of the underlying optimization problem is twofold. The goal of the datacenter is to minimize its offered rewards while the goal of the tenants is to maximize their profit. A two-level hierarchy is proposed for modeling the problem. The upper-level hierarchy models the datacenter planning problem, and the lower-level hierarchy models the task scheduling problem of the tenants. To address these problems, two bio-inspired algorithms are designed and compared for the datacenter planning problem, and an efficient greedy scheduling heuristic is proposed for task scheduling problem of the tenants. Results show the proposed approach reports average improvements between 72.9% and 82.2% when compared to the business as usual approach.


Assuntos
Sistemas Computacionais , Negociação , Algoritmos , Fontes de Energia Elétrica
20.
Nat Commun ; 13(1): 1155, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241662

RESUMO

Many locations around the world have used real-time estimates of the time-varying effective reproductive number ([Formula: see text]) of COVID-19 to provide evidence of transmission intensity to inform control strategies. Estimates of [Formula: see text] are typically based on statistical models applied to case counts and typically suffer lags of more than a week because of the latent period and reporting delays. Noting that viral loads tend to decline over time since illness onset, analysis of the distribution of viral loads among confirmed cases can provide insights into epidemic trajectory. Here, we analyzed viral load data on confirmed cases during two local epidemics in Hong Kong, identifying a strong correlation between temporal changes in the distribution of viral loads (measured by RT-qPCR cycle threshold values) and estimates of [Formula: see text] based on case counts. We demonstrate that cycle threshold values could be used to improve real-time [Formula: see text] estimation, enabling more timely tracking of epidemic dynamics.


Assuntos
COVID-19/transmissão , SARS-CoV-2 , Carga Viral , Número Básico de Reprodução/estatística & dados numéricos , COVID-19/epidemiologia , COVID-19/virologia , Simulação por Computador , Sistemas Computacionais , Epidemias , Hong Kong/epidemiologia , Humanos , Modelos Estatísticos , Pandemias , Carga Viral/estatística & dados numéricos
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