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1.
This paper presents an information-technology-based collaboration framework that facilitates disaster response operations. The collaboration framework incorporates a web collaboration service, radio frequency identification (RFID) tags, a building blackbox system (BBS), a geo-database, and a geographic information system (GIS). Through the integration of these technologies, the framework provides a collaboration medium for first responders, including civil engineers, to cohesively respond to disasters. Access to critical building information, such as construction documents, through the BBS supports assessments of building integrity during disaster response. Building assessment information is stored on RFID tags, which are accessible to first responders through digital devices via a wireless ad hoc network. With on-site assessment information shown on a digital map, decision makers locate, collect, and distribute critical resources through the GIS to first responders. In addition, the decision makers at distributed locations evaluate the incident through discussion sessions, hosted by the web collaboration environment, for integrated decision making. Test-bed simulations for the framework have been carried out with encouraging results at the training ground of the Illinois Fire Service Institute.  相似文献   

2.
When an extreme event hits an urban area, the efficiency and effectiveness of the first response have a profound effect on disaster relief efforts. The redefinition of the civil engineers’ role and responsibilities as first response team members, along with an enhanced collaboration between disaster relief organizations, will greatly improve first response efforts and the securing of affected infrastructures. To improve collaboration efforts, the currently used radio systems-based interaction medium needs to be modified due to the impossibility of storing, retrieving, and transferring digital information, and limited support to implement information dissemination policies. This paper presents a reliable, transparent, and portable mobile ad hoc space for collaboration (MASC) based on a short range wireless communication platform to address these limitations in order to provide more consistent and efficient collaboration among first responders. The system was designed around a robust data redundancy core, and tested through software simulations and by conducting a search and rescue exercise involving civil engineers and firefighters. The simulation results highlight that the number of machines, the replication level, the size of the replication unit, and the wireless communication range are key design elements of the system in providing high availability. The search and rescue exercise allowed this research to confirm the high availability simulation results and to demonstrate that MASC is able to adequately manage and disseminate information in disaster scenarios. These encouraging results allow this research effort to conclude that MASC is able to address these new challenges.  相似文献   

3.
Collection of accurate, complete, and reliable field data is not only essential for active management of construction projects involving various tasks, such as material tracking, progress monitoring, and quality assurance, but also for facility and infrastructure management during the service lives of facilities and infrastructure systems. Limitations of current manual data collection approaches in terms of speed, completeness, and accuracy render these approaches ineffective for decision support in highly dynamic environments, such as construction and facility operations. Hence, a need exists to leverage the advancements in automated field data capture technologies to support decisions during construction and facility operations. These technologies can be used not only for acquiring data about the various operations being carried out at construction and facility sites but also for gathering information about the context surrounding these operations and monitoring the workflow of activities during these operations. With this, it is possible for project and facility managers to better understand the effect of environmental conditions on construction and facility operations and also to identify inefficient processes in these operations. This paper presents an overview of the various applications of automated field data capture technologies in construction and facility fieldwork. These technologies include image capture technologies, such as laser scanners and video cameras; automated identification technologies, such as barcodes and Radio Frequency Identification (RFID) tags; tracking technologies, such as Global Positioning System (GPS) and wireless local area network (LAN); and process monitoring technologies, such as on-board instruments (OBI). The authors observe that although applications exist for capturing construction and facility fieldwork data, these technologies have been underutilized for capturing the context at the fieldwork sites as well as for monitoring the workflow of construction and facility operations.  相似文献   

4.
This paper provides construction industry owners and contractors with information about enhancing their operations using radio frequency identification (RFID) technology. Radio frequency identification involves the use of tags, or transponders, that collect data and manage it in a portable, changeable database; communicate routing instructions and other control requirements to equipment; and can withstand harsh environments. A construction industry-RFID supplier workshop was held to disseminate information about this technology and to generate suitable application ideas for the industry. With the information gathered during the workshop, one application idea was selected and pilot tests conducted to learn more about RFID and its applicability to the material procurement process on a construction site. The pilot tests showed that RFID tags reduced the time required to download data into a company’s material tracking system and could “flag” an item so an entry was not repeated. When scanning the tags, sun glare was not a problem as compared to using bar code labels. Although further analysis is necessary, RFID did show promise of being a beneficial technology as it relates to the materials receiving process. A flowchart is provided to assist contractors and owners in selecting the appropriate RFID system.  相似文献   

5.
Teaching file cases play an important role in the training of nuclear medicine residents; however, film-based teaching files have limitations, such as difficulty in accessing cases in a department with several remote clinical sites. The goal of this project was to develop a digital teaching file with the capability for local and remote (Internet) network access, with the additional requirements that viewing existing cases and addition of new cases be easy and simple. METHODS: The teaching file software (TF-Web) utilizes applications developed for the World-Wide-Web in combination with locally developed programs for importing images, entering case information, indexing, searching, case selection and case editing. The time required to add cases to the TF-Web and to access existing cases from local and remote network sites as well as computer storage requirements were assessed. RESULTS: Cases entered in TF-Web may be viewed either with or without diagnoses and may be accessed with acceptable speed (2-14 sec) from both local and remote network sites. A relatively complex case required 1.2 megabytes of storage, with lesser storage requirements for simpler cases. CONCLUSION: A digital teaching file has been developed that allows easy access from computers located both locally and elsewhere on the Internet. Digital storage requirements are reasonable, and, because of the unique nature of TF-Web, case storage may be distributed among multiple institutions.  相似文献   

6.
Medical records provide essential information for evaluating a patient’s health. Without them, it would be difficult for doctors to make accurate diagnoses. Similar to diagnoses in medical science, building health management also requires building medical records for making accurate diagnoses. At later stages of a building’s life cycle, when the budget is limited, organizations responsible for building repairs and maintenance are unable to digitalize building health diagnoses and keep complete medical records of buildings; as a result, maintenance crews usually cannot fully understand buildings’ overall health conditions and their medical histories, which may result in erroneous diagnoses directly or public safety dangers indirectly. Using the problem-oriented medical record adopted for the medical diagnosis of human diseases, this paper designs a building medical record (BMR), which allows simple electronic archiving, and evaluates its practicability with a case study of school buildings. The purpose of a BMR is to enable maintenance engineers (building doctors), building managers, and contractors of school buildings to have low-cost access to required information for making complete evaluations and maintenance suggestions for buildings.  相似文献   

7.
以某企业针对精炼区域研发的基于物联网技术的设备日常点检及专业点检管理系统为例,着重介绍了该系统的网络构成、无线网络分布及硬件配置。该系统以企业级无线接入设备无线覆盖铜冶炼厂精炼车间各类设备所在的区域,基于物联网手机的Android平台设备点检终端软件,实现了现场设备RFID点检、确认设备状态及自动上传参数到公司设备信息化管理系统等功能。  相似文献   

8.
A bridge monitoring TestBed is developed as a research environment for sensor networks and related decision-support technologies. A continuous monitoring system, capable of handling a large number of sensor data channels and three video signals, is deployed on a four-span, 90-m long, reinforced concrete highway bridge. Of interest is the integration of the image and sensor data acquisition into a single computer, thereby providing accurate time synchronization between the response and corresponding traffic loads. Currently, video and acceleration records corresponding to traffic induced vibration are being recorded. All systems operate online via a high-speed wireless Internet network, allowing real-time data transmission. Elements of the above health monitoring framework are presented herein. Integration of these elements into an automated functional system is emphasized. The recorded data are currently being employed for structural system identification via a model-free technique. Effort is also underway to correlate the moving traffic loads with the recorded accelerations. Finally, the TestBed is available as a resource for verification of new sensor technologies, data acquisition/transmission algorithms, data mining strategies, and for decision-support applications.  相似文献   

9.
Civil infrastructure condition monitoring generates large volumes of sensor data. Huge data size impedes fast and reliable distribution of sensor data, especially for wireless sensor networks. Vibration sensor data plays an important role in many useful structural health monitoring methods. This paper presents a vibration sensor data compression technique based on the lifting scheme wavelet transform (LSWT). Real sensor data from a nine-story building as well as a steel truss bridge was used to examine the compression performance of the LSWT-based vibration sensor data compression technique. It is found that the LSWT-based vibration sensor data compression technique can achieve a very high compression ratio while retaining the basic waveform properties of original sensor data. Additionally, LSWT has a feature that supports progressive compression and thus allows for multiresolution data transmission and retrieval.  相似文献   

10.
Electricity produced by distributed energy resources (DER) located close to end-use loads has the potential to meet consumer requirements more efficiently than the existing centralized grid. Installation of DER allows consumers to circumvent the costs associated with transmission congestion and other nonenergy costs of electricity delivery and potentially to take advantage of market opportunities to purchase energy when attractive. On-site, single-cycle thermal power generation is typically less efficient than central station generation, but by avoiding nonfuel costs of grid power and by utilizing combined heat and power applications, i.e., recovering heat from small-scale on-site thermal generation to displace fuel purchases, DER can become attractive to a strictly cost-minimizing consumer. In previous efforts, the decisions facing typical commercial consumers have been addressed using a mixed-integer linear program, the DER customer adoption model (DER-CAM). Given the site’s energy loads, utility tariff structure, and information (both technical and financial) on candidate DER technologies, DER-CAM minimizes the overall energy cost for a test year by selecting the units to install and determining their hourly operating schedules. In this paper, the capabilities of DER-CAM are enhanced by the inclusion of the option to store recovered low-grade heat. By being able to keep an inventory of heat for use in subsequent periods, sites are able to lower costs even further by reducing lucrative peak-shaving generation, while relying on storage to meet heat loads. This and other effects of storage are demonstrated by analysis of five typical commercial buildings in San Francisco, California, in the United States, and an estimate of the cost per unit capacity of heat storage is calculated.  相似文献   

11.
本文对影响数字资源长期存储的因素进行了简要的分析,并提出了对策。合理使用数字资源长期存储技术,重视信息系统的可靠性分析和维护,注重数据备份和恢复,采取防病毒、访问控制和反入侵策略,强化管理措施的落实,从而最大程度地维护数字资源的存储和利用。  相似文献   

12.
Timely acquisition of construction resource information is an essential task for construction engineers and managers. Due to the harsh and dynamic construction environment, it is not easy to acquire construction information in real time. This paper presents a radio frequency identification (RFID) and ZigBee (IEEE 802.15.4)-based system to manage materials on a busy construction site where a data communications system is not in place. RFID tags are attached to and used to identify various kinds of construction materials, and the ZigBee communication technology is used to wirelessly transfer this information. To confirm the viability of our system, the RFID and ZigBee technologies were assessed using an indoor experiment. Following this, a field experiment was then conducted. On a building construction site, a range of construction materials was identified using RFID tags and this information was transferred to an end user with the help of ZigBee multihop networking. The results of the field experiment showed an acceptable reading range and rate for the proposed system. Therefore, the integrated system with RFID and ZigBee modules demonstrated great potential for improving the existing management processes for construction resources on large and complex construction sites.  相似文献   

13.
Limitations in data transfer between maintenance workers and a central facility management (FM) system result in lower data quality, longer service process times, and ineffective capturing of component maintenance history. Radio frequency identification (RFID) technology provides an opportunity to meet the current needs for uniquely identifying facility components, storing some maintenance history information on the component, and accessing this information on-demand within a facility. There have not been any research studies that tested the performance of active ultrahigh frequency RFID technology on facility components during operations and maintenance phase repetitively over an extended period of time. The objectives of this study were to identify how RFID technology can improve current FM processes and to determine technological feasibility of using RFID within a facility repetitively on a daily basis. The writers tagged fire valves in a facility with RFID tags and conducted a longevity test for sixty consecutive days by simulating tag identification, data access, and entry in real-life conditions. The results demonstrate that current commercially available active RFID technology performs well in a building environment where metallic objects and different obstructions are present. The observed reading distances were approximately half of the reading range expected in open air provided that there are not any massive obstructions between the reader and the tag.  相似文献   

14.
As microscale devices, such as wireless microsensors and noninvasive biomedical implants, continue to shrink and incorporate more functions, energy becomes scarce, thereby shortening operation life. Furthermore, the limited volume space available constrains the stored energy available in state-of-the-art microbattery technologies, such as thin-film lithium ion (Li Ion). For long-lasting life, it is, therefore, necessary to replenish continuously the energy consumed by harnessing, storing, and delivering energy from the environment in situ, i.e., in the package, alongside the application electronics. Operation life would ultimately be independent from storage limitations. The proposed self-contained, system-in-package solution is composed of three different energy-harvesting sources (light, vibrations, and thermal gradients) that sustain the system, while a charger stores the harnessed energy into an in-package Li Ion. Since substantially low-power levels are expected, the sensor must minimize energy consumption and the system, therefore, must be power moded into various operational modes to consume power only when necessary. Experimental measurements show how an electrostatic harvester sources nanoscale currents that can supply 1.18?μW from typical vibrations and, thus, recover the system consumption within 37.3?s.  相似文献   

15.
Indoor localization is needed for guiding people who are not familiar with a facility. This need is more critical when guidance is needed to locate people or objects that need immediate attention. For example, an inexperienced facility worker might need to locate a building component (e.g., leaking pipe) for repair to prevent any damage to a facility or its residents. In such situations, an approach that can help the user to reach his/her destination point (i.e., a component of interest or a specific location in a facility) based on his/her current location is desired. To provide such guidance, the location of a person needs to be determined at a given point in time. This process is known as localization. The objective of this research study is to determine the technological viability of using radio frequency identification (RFID) to support localization. To assess the capability of RFID for localization, the writers conducted multiple field tests under real operating conditions within a facility at Carnegie Mellon University. Hypothesis tests and K-nearest neighborhood algorithm were used to determine the technological feasibility of RFID to support localization. The results showed that it is possible to identify the location of a user using this approach; however, some improvements in accuracy are needed.  相似文献   

16.
An accurate prediction for the response of tall buildings subject to strong wind gusts or earthquakes requires the information of in situ dynamic properties of the building, including natural frequencies and damping ratios. This paper presents a method of identifying natural frequencies and damping ratios of in situ tall buildings using ambient wind vibration data. Our approach is based on the empirical mode decomposition (EMD) method, the random decrement technique (RDT), and the Hilbert–Huang transform. Our method requires only one acceleration sensor. The noisy measurement of the building acceleration is first processed through the EMD method to determine the response of each mode. Then, RDT is used to obtain the free vibration modal response. Finally, the Hilbert transform is applied to each free vibration modal response to identify natural frequencies and damping ratios of in situ tall buildings. The application of the proposed methodology is demonstrated in detail using simulated response data of a 76-story benchmark building polluted by noise. Both the along-wind and across-wind vibration measurements have been illustrated. Simulation results demonstrate that the accuracy of the proposed method in identifying natural frequencies and damping ratios is remarkable. The methodology proposed herein provides a new and effective tool for the parametric identification of in situ tall buildings.  相似文献   

17.
Primary amyloidoma of the chest wall presents as an aggressive tumor that causes local destruction. It is best treated with wide local excision and reconstruction as required, which usually is curative. A search for occult systemic disease also is recommended.  相似文献   

18.
In conjunction search, response latencies usually increase with the number of displayed elements, suggesting serial, self-terminating search through all elements. In line with the results of H. Egeth, R. Virzi, and H. Garbart (1984), the present study shows that Ss do not necessarily search all display elements, but can limit their search to a color-defined subset of elements. The results make clear that selective search for a color-defined subset does not depend on saliency of the subset (Exp 1), that selective search can be purely color-based and does not depend on luminance (Exp 2), and that Ss can flexibly change which subset they are searching (Exp 3). Exp 4 showed that subset-selective search also occurs without fast absent responses as found in Exps 1–3 and that for selective search no explicit instruction is required. Subset-selective search is a likely strategy in conjunction search. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
Various vertebrate inner-ear end organs appear to have switched their sensory function between equilibrium sensing and acoustic sensing over the courses of various lines of evolution. It is possible that all that is required to make this transition is to provide an end organ with access to the appropriate stimulus mode and frequency range. If, as we believe, however, the adaptive advantage of an acoustic sensory system lies in its ability to sort the total acoustic input into components that correspond to individual acoustic sources, and the adaptive advantage of an equilibrium sensory system lies in its ability to compute the total orientation and motion of the head without regard to the individual sources contributing to that orientation and motion, then it is easy to argue that the differences between acoustic and equilibrium sensors should be more profound than simply access to the appropriate stimuli. Effective signal-sorting requires high resolution in both time and frequency; to achieve this resolution, a peripheral tuning structure must be one of high dynamic order (i.e., constructed from multiple independent energy storage elements). If the peripheral tuning structure simply converts head acceleration to head displacement, velocity, or jerk (i.e., provides one or two steps of integration or differentiation with respect to time, where one energy storage element per step is required), then high dynamic order is inappropriate. Because the bullfrog lagena possesses both acoustic and equilibrium sensitive regions, it is especially suited for comparing these two sensor types and addressing the question of dynamic order of tuning. In this paper we report observations of the linear tuning properties of bullfrog lagenar primary afferent nerve fibers obtained by stimulating the lagena with random, dorsoventral micromotion over the frequency range from 10 Hz to 1.0 kHz. Tuning curves obtained by reverse correlation analysis and discrete Fourier transformation were used to estimate the dynamic order of each fiber's associated peripheral tuning structure. We found two classes of lagenar afferent axons--those with lowpass amplitude tuning characteristics (44 units) and those with bandpass amplitude tuning characteristics (73 units). Lowpass units were found to originate at the equilibrium region of the macula, and they exhibited low dynamic order--summed low- and high-frequency slopes (absolute values) ranged from 10 dB/decade to 64 dB/decade, implying dynamic orders of less than one to three (the modal value was equal to one). Bandpass units were found to originate at the acoustic region of the macula, and they exhibited higher dynamic order than lowpass units--summed low- and high-frequency slopes (absolute values) ranged from 53 dB/decade to 185 dB/decade, implying dynamic orders of three to nine (the modal value was equal to five). It appears that while lagenar equilibrium and acoustic sensors both possess access to signals in the acoustic frequency range, lagenar acoustic sensors are tuned by means of peripheral structures with markedly greater dynamic order and consequently markedly greater physical complexity. These results suggest that steep-sloped (high-dynamic-order) tuning properties reflect special adaptations in acoustic sensors not found in equilibrium sensors, and that any evolutionary transition between the two sensor types must have involved profound structural changes.  相似文献   

20.
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