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1.
Sensors (Basel) ; 24(10)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38793949

RESUMEN

The built environment's impact on human activities has been a hot issue in urban research. Compared to motorized spaces, the built environment of pedestrian and cycling street spaces dramatically influences people's travel experience and travel mode choice. The streets' built environment data play a vital role in urban design and management. However, the multi-source, heterogeneous, and massive data acquisition methods and tools for the built environment have become obstacles for urban design and management. To better realize the data acquisition and for deeper understanding of the urban built environment, this study develops a new portable, low-cost Arduino-based multi-sensor array integrated into a single portable unit for built environment measurements of street cycling spaces. The system consists of five sensors and an Arduino Mega board, aimed at measuring the characteristics of the street cycling space. It takes air quality, human sensation, road quality, and greenery as the detection objects. An integrated particulate matter laser sensor, a light intensity sensor, a temperature and humidity sensor, noise sensors, and an 8K panoramic camera are used for multi-source data acquisition in the street. The device has a mobile power supply display and a secure digital card to improve its portability. The study took Beijing as a sample case. A total of 127.97 G of video data and 4794 Kb of txt records were acquired in 36 working hours using the street built environment data acquisition device. The efficiency rose to 8474.21% compared to last year. As an alternative to conventional hardware used for this similar purpose, the device avoids the need to carry multiple types and models of sensing devices, making it possible to target multi-sensor data-based street built environment research. Second, the device's power and storage capabilities make it portable, independent, and scalable, accelerating self-motivated development. Third, it dramatically reduces the cost. The device provides a methodological and technological basis for conceptualizing new research scenarios and potential applications.

2.
Sensors (Basel) ; 22(23)2022 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-36501917

RESUMEN

This paper considers a laser-powered unmanned aerial vehicle (UAV)-enabled wireless power transfer (WPT) system. In the system, a UAV is dispatched as an energy transmitter to replenish energy for battery-limited sensors in a wireless rechargeable sensor network (WRSN) by transferring radio frequency (RF) signals, and a mobile unmanned vehicle (MUV)-loaded laser transmitter travels on a fixed path to charge the on-board energy-limited UAV when it arrives just below the UAV. Based on the system, we investigate the trajectory optimization of laser-charged UAVs for charging WRSNs (TOLC problem), which aims to optimize the flight trajectories of a UAV and the travel plans of an MUV cooperatively to minimize the total working time of the UAV so that the energy of every sensor is greater than or equal to the threshold. Then, we prove that the problem is NP-hard. To solve the TOLC problem, we first propose the weighted centered minimum coverage (WCMC) algorithm to cluster the sensors and compute the weighted center of each cluster. Based on the WCMC algorithm, we propose the TOLC algorithm (TOLCA) to design the detailed flight trajectory of a UAV and the travel plans of an MUV, which consists of the flight trajectory of a UAV, the hovering points of a UAV with the corresponding hovering times used for the charging sensors, the hovering points of a UAV with the corresponding hovering times used for replenishing energy itself, and the hovering times of a UAV waiting for an MUV. Numerical results are provided to verify that the suggested strategy provides an effective method for supplying wireless rechargeable sensor networks with sustainable energy.

3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 25(3): 703-7, 2008 Jun.
Artículo en Chino | MEDLINE | ID: mdl-18693460

RESUMEN

Instantaneous chaometry was defined on uniformity theory constructed by the present authors. The sample data, sinus heart rate data and arrhythmia heart rate data from MIT-BIH were analyzed with instantaneous chaometry (ICM); the situation not being distinguished with HRV can be differentiated with ICM. The normal sinus rhythm was found to be of three evident characteristics: (1) instant returning to zero, (2) stability-stable characteristic of ICM on the initial position, (3) interval of mean: 2-7, variance: 1.5-5. The third characteristic shows that the variability of ICM is necessary. The studies on arrhythmia database showed that arrhythmia cases exhibited no returning to zero, nonstability of ICM on the initial position, too small mean or standard deviation, respectively. Evidently, the arithmetic of ICM is simple; ICM can be easily applied in clinical and pathologic analyses.


Asunto(s)
Arritmias Cardíacas/fisiopatología , Electrocardiografía/métodos , Frecuencia Cardíaca/fisiología , Procesamiento de Señales Asistido por Computador , Nodo Sinoatrial/fisiología , Humanos , Masculino , Persona de Mediana Edad
4.
Ying Yong Sheng Tai Xue Bao ; 16(6): 1002-6, 2005 Jun.
Artículo en Chino | MEDLINE | ID: mdl-16180742

RESUMEN

In this paper, the implement steps of natural forest protection program grading (NFPPG) with neural network (NN) were summarized, and the concepts of program illustration, patch sign unification and regress, and inclining factor were set forth. Employing Arc/Info GIS, the tree species diversity and rarity, disturbance degree, protection of channel system, and classification management in Moershan National Forest Park were described, and, used as the input factors of NN, the relationships between NFPPG and above factors were analyzed. Through artificially determining training samples, the NFFPG of Moershan National Forest Park was built. Tested with all patches in the park, the generalization of NFFPG was satisfied. NFPPG took both the classification management and the protection of forest community types into account, as well as the ecological environments. The excitation function of NFPPG was not seriously saturated, indicating the leading effect of inclining factor on the network optimization.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Agricultura Forestal , Redes Neurales de la Computación , Árboles/crecimiento & desarrollo , Sistemas de Información Geográfica
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