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Purpose Common performance metrics for outpatient clinics define the time between patient arrival and entry into an examination room as “waiting time.” Time spent in the room is considered processing time. This characterization systematically ignores time spent in the examination room waiting for service. If these definitions are used, performance will consistently understate total waiting times and overstate processing times. Correcting such errors will provide a better understanding of system behavior. Methods and materials In a radiation oncology service in an urban academic clinic, we collected data from a patient management system for 84 patients with 4 distinct types of visits: consultations, follow-ups, on-treatment visits, and nurse visits. Examination room entry and exit times were collected with a real-time location system for relevant care team members. Novel metrics of clinic performance were created, including the ratio of face time (ie, time during which the patient is with a practitioner) to total cycle time, which we label face-time efficiency. Attending physician interruptions occurred when the attending is called out of the room during a patient visit, and coordination-related delays are defined as waits for another team member. Results Face-time efficiency levels for consults, follow-ups, on-treatment visits, and nurse visits were 30.1%, 22.9%, 33.0%, and 25.6%, respectively. Attending physician interruptions averaged 6.7 minutes per patient. If these interruptions were eliminated, face-time efficiencies would rise to 33.2%, 29.2%, 34.4%, and 25.6%, respectively. Eliminating all coordination-related delays would increase these values to 41.3%, 38.9%, 54.7%, and 38.7%, respectively. Conclusions A real-time location system can be used to augment a patient management system and automate data collection to provide improved descriptions of clinic performance.

This paper presents the analysis of 14 years of cloud-to-ground lightning activity observation in Colombia using lightning location systems (LLS) data. The first Colombian LLS operated from 1997 to 2001. After a few years, this system was upgraded and a new LLS has been operating since 2007. Data obtained from these two systems was analyzed in order to obtain lightning parameters used in designing lightning protection systems. The flash detection efficiency was estimated using average peak current maps and some theoretical results previously published. Lightning flash multiplicity was evaluated using a stroke grouping algorithm resulting in average values of about 1.0 and 1.6 for positive and negative flashes respectively and for both LLS. The time variation of this parameter changes slightly for the years considered in this study. The first stroke peak current for negative and positive flashes shows median values close to 29 kA and 17 kA respectively for both networks showing a great dependence on the flash detection efficiency. The average percentage of negative and positive flashes shows a 74.04% and 25.95% of occurrence respectively. The daily variation shows a peak between 23 and 02 h. The monthly variation of this parameter exhibits a bimodal behavior typical of the regions located near The Equator. The lightning flash density was obtained dividing the study area in 3 × 3 km cells and resulting in maximum average values of 25 and 35 flashes km - 2 year - 1 for each network respectively. A comparison of these results with global lightning activity hotspots was performed showing good correlation. Besides, the lightning flash density variation with altitude shows an inverse relation between these two variables.

Current active transportation literature within children is based almost exclusively on questionnaire measures of the trip to school. This literature suggests that the walkability of the built environment can influence active transportation to school. The purpose of this study was to use objective measures to examine the relationship between neighborhood walkability and children's active transportation to school and other destinations. This was a cross-sectional study of 367 children and early adolescents (aged 10–13 years) from Kingston, Ontario, Canada. Participants wore a Garmin Forerunner 220 GPS watch during waking hours for seven consecutive days. Personal Activity Measurement Location System (PALMS) software used the GPS data to identify trips, and for each trip the time spent in that trip and the trip modality (active or passive). GIS measures of connectivity, proximity to destinations, and pedestrian infrastructure and safety were used to create a walkability index. Participants living in the neighborhoods with the highest walkability quartile spent an average of 16.2 min/day (95% CI: 11.8, 22.4) in active transportation while those in the lowest walkability quartile spent an average of 7.1 min/day (95% CI: 5.0, 10.4) in active transportation. Consistent patterns between walkability and active transportation were observed in age, sex, and season of study subgroups. An increase in active transportation minutes was seen across walkability quartiles for all of the most common active travel destinations (i.e., home, school, other people's homes). In conclusion, in this study of 10–13 year olds, those living in the most walkable neighborhoods accumulated more than twice as much active transportation than those living in the least walkable neighborhoods.

Construction is one of the most dangerous industrial sectors. Struck-by object or equipment is one of the main causes of fatal accidents on construction sites. Although many regulations have been designed for preventing struck-by accidents, they still happen and lead to many injuries and fatalities. The application of real-time location systems (RTLS) on construction sites provides new possibilities in construction safety management. Previous researchers have proposed using RTLS to track the locations of workers and equipment on construction sites to improve construction safety. However, they have the limitation of cabling problems. Also, providing effective safety alerts to workers within dangerous proximity to equipment has not been well addressed. This paper aims to develop a method for detecting the proximities as well as providing proximity safety alerts to workers on construction sites using Bluetooth Low Energy (BLE) RTLS. Here, vibro-tactile alerts representing different cases of proximities were defined. Unnecessary alerts were filtered out to avoid desensitizing workers. A number of tests were conducted on a construction site to test the prototype system developed based on the proposed method. The results indicate that the system is capable of detecting proximities and generating timely vibro-tactile alerts, which can be easily perceived by the workers.

Modern lightning location systems (LLSs) have become a useful tool in confirming or negating lightning as a cause of damage in forensic investigations. There are uncertainties in the reported locations of detected lightning that arise from electromagnetic propagation errors and need to be considered when used in forensic investigations. Methods to evaluate regions of confidence for individual stoke reports or to calculate probabilities of individual strokes having attached in a region are available but no consistent method for evaluating the probability that an area or asset of interest was struck/damaged by lightning. This paper discusses a methodology for calculating a probability that considers all detected lightning events relevant to such an investigation, and not just individual strokes. The method is based on previous work done by Huddleston et al. and adds to it using conditional probability theory. A case study, a photovoltaic plant where a solar panel was found damaged subsequent to a storm, is used to demonstrate the concepts of the methodology. It is possible to show that there is a 71% chance that the panel group from which the damaged panel came, was struck by lightning using LDN data alone. This can be compared with the rest of the solar panel plant (where it was noted that other solar panels had been replaced after the same storm) which had a 97% chance of having been struck by lightning. It is also shown how grouping strokes into flashes and using the methodology to calculate which area was struck by each flash, indicates the true strike area of interest better than only using individual strokes.

Highlights • Contact tracing is an essential step in infectious disease control and prevention. • Using Electronic medical record (EMR) is challenging and misses a number of potential exposures. • Real time location system (RTLS) doubled the potential exposures list for pertussis disease beyond the conventional method of EMR-based contact identification • RTLS is more efficient and timely in the process of contact tracing. • Further studies with larger sample size are needed to confirm the findings., Background Contact tracing is the systematic method of identifying individuals potentially exposed to infectious diseases. Electronic medical record (EMR) use for contact tracing is time-consuming and may miss exposed individuals. Real-time location systems (RTLSs) may improve contact identification. Therefore, the relative effectiveness of these 2 contact tracing methodologies were evaluated. Methods During a pertussis outbreak in the United States, a retrospective case study was conducted between June 14 and August 31, 2016, to identify the contacts of confirmed pertussis cases, using EMR and RTLS data in the emergency department of a tertiary care medical center. Descriptive statistics and a paired t test (α = 0.05) were performed to compare contacts identified by EMR versus RTLS, as was correlation between pertussis patient length of stay and the number of potential contacts. Results Nine cases of pertussis presented to the emergency department during the identified time period. RTLS doubled the potential exposure list (P

Thunderstorm electrical structures favouring cloud-to-ground lightning were investigated through a Lightning Mapping Array (LMA), an accurate three-dimensional lightning location system that allows inferring the heights of the regions of charge. The present study focused on classical, convective-scale thunderstorms, aiming to shed new light on how the charge structure affects lightning production, especially the cloud-to-ground fraction, including flash rate and polarity. Results showed that lightning flashes mainly initiate at two levels, around -41 °C (9,150 m MSL) and around -7 °C height (4,730 m MSL). These initiation levels, located between the dominant positive and negative charge regions, allowed to define three main charge structures: an upper dipole (positive above negative), a classical tripole and a lower dipole (negative above positive). Several differences were found between the three categories in terms of the cloud-to-ground lightning production: (i) the classical tripole structure is the one presenting a higher cloud-to-ground flash rate (5.2 flashes·min-1); (ii) in terms of intensity, the presence of an upper positive charge region is more relevant than a lower positive below the main mid negative; (iii) conversely, the lower positive favours higher cloud-to-ground peak currents; (iv) A higher upper positive charge region favours a higher cloud-to-ground rate.

Lightning is one of the most dangerous natural phenomena, able to produce high impacts and damage on human beings and infrastructures (civil, electric, telecommunications, etc..) even though perception of it as a hazard is low. The aim of this study is to provide a detailed analysis of lightning occurrence throughout the Italian territory to support the work of different operators and researchers (physicists, meteorologists and electric/ITC engineers) improving knowledge about the main properties of lightning. Thus, an in-depth study of the statistics of lightning activity across the Italian territory for the period 2010–2019 is performed in detail using the data collected by the Italian Lightning Detection Network SIRF (Sistema Italiano Rilevamento Fulmini), part of the European network EUCLID (European Cooperation for Lightning Detection). This analysis presents general properties such as Ground Stroke Density (GSD) and the positive to negative strokes ratio by highlighting how seasonal, geographical and orographic factors influence their values. Then, attention is focused on lightning peak current, on flash multiplicity and on the distance between the points of impact of different strokes within a flash. Comparison made with other articles available in the literature reveals good agreement with studies conducted with other LLS data in Mediterranean regions. On the other hand, some differences appear with direct current measurements that can be partly ascribed to Lightning Location System (LLS) detection contamination (confirming other comparative studies of LLS and instrumented tower findings), to differences between tower and ground measures, and to the presence of regional differences.

The passive location method based on angle measurement is studied, the low positioning accuracy and Geometric Dilution of Precision (GDOP) on some target azimuth of dual-station angle measurement location system are founded. Based on the structural characteristics of the airborne platform, an infrared passive angle measurement location method for the single plane is presented. According to the orthogonal method, four measuring stations are loaded onto the airborne platform, they are composed of two orthogonal angle measurement location systems. By choosing the location information of the two systems properly, the GDOP problem can be overcome effectively. Finally, the simulation results show that the method can effectively overcome the GDOP problem and improve the positioning accuracy.

Current onsite safety management always relies on time-consuming predefinitions of hazardous zones based on the managers’ personal capabilities. However, in a typical labor-intensive industry such as construction, the workers themselves can provide a wealth of information for hazard identification. Historical accident-free working locations on site provide a valuable means of recognizing safe workplaces. This paper presents an approach to the automated classification of construction site zones derived from the location tracks of workers collected from a real-time location system (RTLS). Through data mining, filtering and analysis, the location tracks are transformed into grid density maps and continuous density maps. These illustrate the characteristics of spatial-temporal activities onsite as well as providing a visual representation of the distribution of safe and hazardous individual workplaces. A personnel hazard map is generated automatically based on historical accident-free location tracks from a field project using the proposed approach. Compared with the actual workplaces in terms of accuracy, precision, sensitivity and specificity, the evaluation result reveals that the hazardous areas on a construction site can be automatically classified to improve the workplace management of individual workers. The contributions of this research include an automated zone classification algorithm and an evaluation framework consisting of four indicators for hazard awareness onsite.

The development of Internet of Things (IoT) has made a profound impact on establishing digital manufacturing workshop. In particular, to satisfy the needs of positioning, tracking and monitoring of manufacturing resources, the Real-Time Location System (RTLS) is developed on the basis of Radio Frequency Identification (RFID) and Ultra Wide Band (UWB). Firstly, the Holographic Workshop Map (HWM) is defined and designed to construct the framework of the proposed RTLS. Then, the real-time location platform, which is composed of RFID-based regional positioning and UWB-based precise positioning methods, is built to get the real-time location information of all kinds of manufacturing factors in the large discrete manufacturing workshop. Finally, a simulative 8-workstations workshop is constructed and a prototype system is developed to verify the proposed method. The experimental results show that the proposed RTLS is feasible in real-time locating and monitoring.

The effects of wind turbines (WTs) on cloud-to-ground (CG) lightning activities have not been fully understood. Based on the CG lightning data obtained from lightning location system (LLS), this paper quantified and compared the characteristics of CG lightning activities, including lightning density, multiplicity, polarity, peak current, and seasonal distribution, before and after the erection of the wind farms (WFs) in China. The shielding effect of offshore WTs was also analyzed. The results showed that, since the WF located in the southeast China was constructed, the return stroke density, flash density and multiplicity within a radius of approximately 0.5 km around the WTs increased by 27.9%, 7.3% and 10.9% in terms of change rate, respectively; within the same distance, the negative median peak current was -23.9 kA, and the positive median peak current was 12.3 kA. WTs located at the edge of the offshore WF had a shielding effect on the internal WTs. The proportion of spring lightning was up to 41.4% in southwest China. Winter lightning was rare in southern China. The results suggest more detailed factors, such as the local terrain, climate and the layout of WFs, are needed when assessing the lightning risk to WTs.

While in-depth studies of lightning deaths can be found in the literature, rarely do such investigations they utilize a multidisciplinary approach, analysing both the medical and electrical aspects of a case. Even more rare, is to find such studies on cases from the developing world such as Africa and South-East Asia - particularly in tropical countries with very high lightning exposure. This paper details the forensic investigation of two lightning deaths that took place during a weekend in February 2020, in South Africa. One event was eye witnessed and the other was not (Case A and B). The investigation involves multidisciplinary forensic examination including case histories, site analysis (including soil resistivity measurements), medical autopsies, lightning location system data analysis and voltage gradient estimations. In both cases, lightning is determined to be the cause of death. In Case A, we confirm that the responsible flash must have attached within close proximity to the deceased, if not a direct strike and in Case B we confirm direct strike as the most probable mechanism of death. The importance of clothing examination in the forensic studies of lightning victims is noted along with a discussion of the lightning safety issues at play, and recommendations for avoiding such incidents in developing world countries.

In response to the growing demand to improve reliability and quality of power supply, distributed monitoring devices are gradually being implemented in distribution networks. On the other hand, utilities are demanding more accurate and reliable fault location systems to reduce the economic impact of power outages. This paper presents a novel method that takes full advantage of all available measurements to provide an accurate fault location. The developed method first uses an iterative state estimation based algorithm to find the nearest node to the fault location. It then examines all lines connected to the selected node and locates the fault. The performance of the proposed method is studied by simulation tests on a real 13.8 kV, 134-node distribution system under different fault scenarios. The results verify the accuracy of the algorithm and its robustness even under uncertain measured data. The method robustly handles measurement errors, and is applicable to any distribution network with laterals, load taps and heterogeneous lines.

Cattle behavior recorded by video was compared to locational data.The probability of engaging behavior when in a zone of interest was determined.Probability of behavior varied by individual animal and period of day.This data improves the interpretation of real time location system data. IntroductionAnimal location can be monitored and described through remote, real-time location systems (RTLS) that locate animals within a defined housing area on a continuous basis using an X, Y coordinate system. These systems only collect locational data and do not measure participation in behaviors of interest. Video recording is a method for documenting animal behavior but analysis of the data is time consuming and prone to error. The objective of this research was to determine the probability of calves participating in eating or drinking behavior as classified by video when located by RTLS within 0.3m of the hay, grain, or water. ResultsTwo, separate 24h trials monitored two independent groups of cattle in a dry lot pen. Trial 1 monitored 2- to 3-month old Holstein steer calves (n=16) and Trial 2 monitored 4- to 5-month old beef heifer calves (n=9). Video observers categorized each calf according to target behaviors as 0 (no behavior) or 1 (behavior observed) and video data was compared to RTLS data classifying calves as in-the-zone of interest. Analysis accounted for lack of independence of samples due to observer, repeated measures of calves, and period of the day (6h block). Significant differences in the probability of engaging in a behavior of interest were observed between calves and periods of the day. When located in the zone of interest categorized as "in-the-water" by RTLS, individual calves displayed a model-estimated median (min, max) probability of drinking as categorized by video observation of 42.09% (26.58, 60.05) in Trial 1 and 54.49% (40.15, 75.01) in Trial 2. The model-estimated median probability of eating while located in the zone categorized as "in-the-hay" was 88.27% (65.10, 99.26) and 67.87% (22.63, 84.13) in Trials 1 and 2, respectively. The model-estimated median probability of eating when in-the-grain in Trial 1 was 59.59% (9.87, 88.07) and was 51.97% (36.86, 77.51) in Trial 2. ConclusionsThe data from this trial provide an estimate of the median probability of participating in eating and drinking behavior when located at feeding and watering locations as categorized by RTLS. The observed data also highlights the significant variability in the probability of participating in a behavior of interest when at a location of interest between calves. This trial provides an improved understanding of the association between RTLS data and some of the behaviors of interest to researchers.

Context-aware applications adapt their functionalities based on users’ profiles and their current contexts. Complementarily, a trail is the history of the contexts visited by a user. Trails enable applications to explore the users’ past behavior. In this sense, trail awareness is considered an evolution of the context awareness, because applications explore an additional and more complete information source. This article proposes a model for trail-aware commerce support, called TrailTrade. The model uses the dealers’ profiles, contexts and trails to find deal opportunities and promote business transactions. Dealers may be people or companies offering and/or looking for something. TrailTrade supports the trade in goods and the exchange or sale of experience or knowledge. The model was implemented including an indoor location system and a deal assistant on mobile devices. The prototype was installed in a real environment and used to simulate a city composed of houses, a metro and a mall. This environment allowed a practical application in a scenario. This test evaluated the TrailTrade’s functionalities, mainly its trail awareness support. The results were encouraging and show potential for applying TrailTrade in real situations, fostering negotiations through the past behavior of dealers.

With anchor positions and measurements of distances between an object and anchors, positioning algorithms calculate the position of an object, e.g. via lateration. Positioning systems require calibration and configuration prior to operation. In the past, approaches employed reference nodes with GPS or other reference location systems to determine anchor positions. In this article, we propose an approach to determine anchor positions without prior knowledge. We evaluate our approach with simulations and real data based on the Decawave DW1000 radio and show that the error is proportional to the mean error of the distance estimation.

Using an S-band Doppler radar and a very high frequency (VHF) radiation source location system, 254 lightning flashes occurring in stratiform regions (stratiform lightning flashes) of 14 mesoscale convective systems (MCSs) in Chongqing, China, were observed and used to analyze the structure of vertical reflectivity in the area around the lightning channel. In most stratiform lightning flashes, the vertical reflectivity structures can be grouped into three general categories: single-layer, double-layer, and triple-layer. The single-layer structure flashes are the most numerous (65.0%), followed by the double-layer (26.8%) and triple-layer (1.2%) flashes. The regions with the single-layer structure and the double-layer structure are inferred to have mesoscale updrafts of different intensity in the middle of stratiform region. Around 62.3% of the single-layer structure flashes initiate within 0–4 km above the vertical reflectivity core, and the main initiation range of these flashes widens with increasing value of the vertical reflectivity core. Around 49.2% and 12.7% of the double-layer structure flashes initiate within 3–6 km and 1–2 km above the vertical reflectivity core, respectively. The probability of lightning initiation at a greater distance to the vertical reflectivity core is higher than that at a shorter distance. This may imply that some electrifications occurring during the melting process are not as strong as expected and a non-riming non-inductive charging process occurring in a weak but broad mesoscale updraft in the middle of stratifom region may be more important for initiation of stratiform lightning flashes.

The current status of the Japanese coastal region shows that winter lightning has seriously damaged wind turbines owing to its larger electrical charge than summer lightning. In Japan, 64% of serious wind turbine damage occurred in winter. Typically, lightning flash density is used to evaluate lightning risk in an area. Herein, we discuss the extent of lightning damage on wind turbines in Japan and cloud-to-ground (CG) lightning flash density based on the Japanese Lightning Detection Network, the largest lightning location system in Japan. Consequently, we found no correlation between the number of lightning flashes hitting wind turbines and summer lightning ground flash densities in the surrounding areas of a wind turbine. Approximately 95% of the lightning flashes that hit the turbine occurred in winter. The probabilities of lightning flashes hitting wind turbines were 0.12% in summer and 5.6% in winter. We developed a map showing the probability of lightning flashes hitting wind turbines in Japan. The probabilities obtained using this map were quite similar to the CG lightning flash density in winter. Therefore, we propose that lightning risk for wind turbines should not be evaluated based on the annual CG lightning flash density in Japan.

The construction industry accounted for more than 17% of fatal work injuries, i.e., 806 counts of death, in the U.S. in 2012. Approximately 75% of struck-by fatalities in the construction industry are reported to have been caused by heavy equipment. Researchers have addressed the need for the enhanced safety of earthwork equipment in two different streams, namely using advanced planning methods to avoid overlaps between the workspaces of different activities of equipment or using real-time tracking technologies to avoid the collision between equipment in the immediate future. However, none of these solutions enables the equipment to reliably predict the operation of other pieces of equipment for a long-enough time window to find a collision-free path using path re-planning. Accordingly, the present paper proposes a novel method to generate risk maps based on the integration of the pose and state data of the equipment with near-real-time simulation and considering the proximity-based and visibility-based risks. These risk maps are used to define dynamic workspaces that can in turn be used to perform path re-planning in a timely manner. The proposed method is implemented and tested in a case study. In light of the results of the case study, it is found that the proposed method is providing a reliable basis for the safety analysis of earthwork sites by generating workspaces with different levels of risk that can be used to provide timely alerts to different equipment and crews.

In recent years, lightning and thunderstorm detection techniques have been rapidly developed in many regions of Asia. As the most populous continent, hazards caused by lightning and related phenomena are being paid more and more attentions and lightning observations and detections are booming in many countries. In this paper, we will give a brief review on recent progress of lightning and thunderstorm detection techniques in Asia. First, we will introduce several widely used lightning location systems including VHF interferometers, VHF time-of-arrival systems and LF time-of-arrival systems. As an example, a newly-developed system called BOLT is described and recent observation results are introduced. Second, we will review studies of a special type of intracloud discharge called “narrow bipolar event” (NBE). NBE studies in Asia are flourishing in recent years and are making great contributions to the understanding of various properties of NBE. Finally, we will introduce a fast-scanning phased array radar (PAR) system installed in Osaka University. This radar system has a temporal resolution of 10–30 s, which is much faster than the traditional weather radar and is ideal for observations of fast-evolving storm structures and the analysis of their relationship with lightning activities. Preliminary observation results with PAR are described.

In terms of safety and the efficient management of spent fuel storage, detecting failed fuel is one of the most important tasks in a CANada Deuterium Uranium (CANDU) reactor operation. It has been successfully demonstrated that in a CANDU reactor, on-power failed fuel detection and location systems, along with alarm area gamma monitors, can detect and locate defective and suspect fuel bundles before discharging them from the reactor to the spent fuel storage bay. In the reception bay, however, only visual inspection has been used to identify suspect bundles. Gaseous fission product and delayed neutron monitoring systems cannot precisely distinguish failed fuel elements from each fuel bundle. This study reports the use of a sipping system in a CANDU reactor for the integrity assessment of spent fuel bundles. The integrity assessment of spent fuel bundles using this sipping system has shown promise as a nondestructive test for detecting a defective fuel bundle in a CANDU reactor.

A training period of lightning location data usage has been carried out in Nepal during the pre-monsoon season April–June 2012. The training was one part of a Finnish–Nepalese Project (FNEP) between the Department of Hydrology and Meteorology of Nepal (DHM) and the Finnish Meteorological Institute (FMI). FNEP aimed for the development of operational meteorological readiness in a developing country such as Nepal. The lightning location training included the introduction to lightning location techniques and principles and the actual hands-on training for the operational DHM forecasters. The lightning location system used was the Vaisala long range Global Lightning Dataset 360 (GLD360), which has practically a global coverage. During the three months of training, a dataset of Nepalese lightning was also collected, indicating the pre-monsoon thunderstorm characteristics of Nepal.

What are the characteristics of lightning that influence the probability that an individual stroke will ignite a wildfire? It is generally accepted that long continuing current following some return strokes is the cause of ignition in forest fuels. However, because these low-level currents are not detectable with operative Lightning Location Systems, other lightning characteristics correlating with its occurrence have been proposed and used to estimate ignition probability. These variables are typically: flash multiplicity, stroke polarity, stroke peak current and flash interstroke interval. The region of Catalonia is prone to forest fires, and to set a probability of ignition to each cloud-to-ground flash could be useful in wildfire management. A set of more than 500 lightning-ignited wildfires that occurred in Catalonia between 2004 and 2009 was analyzed, in order to find which flash/stroke characteristics are related to ignition. Lightning activity was gathered by the Lightning Location System of the Meteorological Service of Catalonia. Lightning related to these wildfires were selected from the lightning database using a proximity index. The statistical analysis has shown that the sample of lightning causing ignition does not present any characteristic that differentiates it from the overall population. Polarity percents, multiplicity and peak current frequency distributions in the lightning causing ignition set are similar to the climatological ones. Besides this analysis, a high-speed video field campaign of natural lightning recordings was conducted, to obtain new insight into the characteristics of lightning bearing a continuing current. Video analysis has shown that almost each kind of cloud‐to‐ground (CG) flash (negative, positive, single or multiple stroke) can have a continuing current component. Only negative strokes with peak currents above 20 kA were not followed by long continuing current. These results are similar to studies carried out in other regions.

The Guangdong Comprehensive Observation Experiment on Lightning Discharge (GCOELD) was conducted from 2006 to 2011 in Conghua, Guangdong, China. In GCOELD, the acoustical, optical, electrical and magnetic signals of triggered lightning and natural lightning were measured. For the triggered lightning, the peak current of the return strokes (RSs) ranged from 6.67 to 31.93 kA. The transferred charge within 1 ms after the beginning of the RS ranged from 0.44 to 4.16 C. The peak currents showed different-function correlations with average rate of rise between 10 and 90%, maximum rate of rise, charge transfer and action integral. The 2D propagation speed of the upward positive leader for the triggered lightning was of the order of 10 4 –10 5 m s − 1 . The speed of the downward negative leader involved in altitude-triggered lightning was approximately 10 5 m s − 1 . The characteristics of induced voltages produced by triggered lightning on a power line and signal line of an automatic weather station were measured and analyzed. The maximum induced voltage generated by the RS on the overhead power line (1200 m in length and 2 m above the ground) exceeded 10 kV. The maximum induced voltage on a vertical 10-m signal line was 3.10 kV. The triggered-lightning technique was also used to test the detection efficiency and location precision of the lightning location system (LLS) in Guangdong. It was explored that the Guangdong LLS yielded detection efficiency and location error of 92% and 760 m, respectively, for triggered flashes. For RSs of the triggered lightning, the peak currents given by the LLS deviated from those measured at the base of the lightning channel by 16% on average.

This document presents an innovative solution to extend the lifetime of autonomous positioning systems used in the transportation sector. The integration of solar and mechanical energy harvesters along with the appropriate conditioning circuit into the main location system, are the key to reduce the dependence of batteries. Also, a toll detection circuit was added to provide information about crossing toll stations.

Magnetic Flux Leakage detector (MFL_PIG) is widely used in long-range pipeline inspection. Acoustic above ground marking device is an important part of the location system in the MFL_PIG. A novel above ground marking algorithm based on function fitting is proposed to reduce marking error of above ground markers (AGMs). Experiments were carried out on a 2.5 km long pipeline on site. The results demonstrate that the function fitting algorithm has higher precision and anti-interference ability than traditional marking method-extreme value algorithm, and it works very well when SNR of the signal is greater than −2 dB.

Peripherally inserted central catheters (PICCs) are frequently placed at the bedside. The purpose of our study was to evaluate the efficacy of the Sherlock II tip location system (Bard Access Systems, Salt Lake City, UT), which offers electromagnetic detection of the PICC tip to assist the operator in guiding the tip to a desired location. We performed a retrospective review of patients who had a bedside PICC using the Sherlock II tip location system. Three hundred seventy-five of 384 patients (97.7%) had the catheter tip positioned appropriately. Our results suggest that the Sherlock II tip location system is an efficacious system for bedside PICC placement.

The performance of GLD360 (Global Lightning Dataset 360) long range lightning location system has been studied over Europe. The analysis has been done by comparing the lightning location data of GLD360 from year 2011 (May–September) to a reference system, which here is EUCLID (European Cooperation for Lightning Detection); EUCLID is a good reference system because its performance has been analyzed around Europe in many previous studies, especially in Austria. We show results about the relative performance of GLD360 from Austria, Scandinavia, North Sea and Spain, as well as the general relative performance over the whole Europe. Our results indicate that (i) the relative detection efficiency (RDE) of GLD360 varies from about 36% to 170% in the EUCLID coverage area, (ii) GLD360 daily RDE in Austria in July varies from 4.4% to 80.8%, (iii) the median relative location accuracy of GLD360 in Austria in July is 2.8 km, (iv) the diurnal variation in Austria in July shows similar feature for both systems, i.e., largest percentage at 16–17 UTC, (v) the median peak current of negative (positive) strokes for GLD360 is 14 kA (11 kA) and for EUCLID for the same area and period 9 kA (7 kA), (vi) the correlation between EUCLID and GLD360 peak current is r = 0.72, and (vii) the boundary of the efficient detection area of EUCLID can be clearly seen when the GLD360 RDE increases above 100%; this coverage boundary is extremely sharp. Our results show that a comparison of this kind reveals many interesting performance issues regarding both the comparative and the reference network, especially the areas where the reference network performs poorly.

The peak currents of seven first and ten subsequent strokes measured at the instrumented tower of Morro do Cachimbo Station and estimated by the Brazilian lightning location system were compared. The evaluation shows a trend of the LLS to underestimate the amplitudes of currents. The mean ratio between the measured and the estimated peak currents exceeds 1.4 for first strokes and 1.7 for subsequent strokes. It was verified that this ratio could be significantly decreased using parameters capable of properly representing the attenuation of the propagated lightning electromagnetic signal.

This paper considers a location system where a number of deployed sensor nodes collaborate with objects that need to be localized. Unlike existing works, we focus on reducing the energy consumption of the sensor nodes, which are assumed to be static and run on limited battery power. To minimize the total wake-up time of the sensor nodes, we control the transmission schedule of each object. Because it is difficult to find an optimal solution to the considered optimization problem, we consider an approach to this problem that consists of two steps: (1) create an equivalent modified graph coloring subproblem, and (2) permute the coloring result to obtain a best possible solution. We adopt some existing graph coloring algorithms for step 1 and find two properties of optimal schedules that can be used to confine the search space for step 2. Additionally, we propose a heuristic algorithm that aims at significantly reducing the complexity for the case where the confined search space is still too large. The performance of our heuristic algorithm is evaluated through extensive simulations. It is shown that its performance is comparable to that of the simulated annealing algorithm, which gives a near-optimal solution.

This work analyses the waveshapes of continuing currents and parameters of M-components in positive cloud-to-ground (CG) flashes through high-speed GPS synchronized videos. The dataset is composed of only long continuing currents (with duration longer than 40 ms) and was selected from more than 800 flashes recorded in Sao Jose dos Campos (45.864°W, 23.215°S) and Uruguaiana (29.806°W, 57.005°S) in Southeast and South of Brazil, respectively, during 2003 to 2007 summers. The videos are compared with data obtained by the Brazilian Lightning Location System (BrasilDAT) in order to determine the polarity of each flash and select only positive cases. There are only two studies of waveshapes of continuing currents in the literature. One is based on direct current measurements of triggered lightning, in which four different types of waveshapes were observed; and the other is based on measurements of luminosity variations in high-speed videos of CG negative lightning, in which besides the four types above mentioned two additional types were observed. The present work is an extension of the latter, using the same method but now applied to obtain the waveshapes of positive CG lightning. As far as the authors know, this is the first report on M-components in positive continuing currents. We also have used the luminosity-versus-time graphs to observe their occurrence and measure some parameters (duration, elapsed time and time between two successive M-components), whose statistics are presented and compared in detail to the data for negative flashes. We have plotted a histogram of the M-components elapsed time over the total duration of the continuing current for positive flashes, which presented an exponential decay (correlation coefficient: 0.83), similar to what has been observed for negative flashes.

To overcome the drawback of a short operation range and low-resolution of a passive location system using a civil communication signal, the new idea that utilizes code division multiple access (CDMA) signal and repeater is disposed off. First, the CDMA passive location model and observation function are given, and the error source and error range are analyzed. Subsequently, the CDMA passive location algorithm in a repeater environment is described and simulated. The simulation result shows that the algorithm can provide the location value with high accuracy.

We present a system for monitoring and locating everyday items using mobile phones. The system is based on phones which are enhanced with the capability to detect electronically tagged objects in their vicinity. It supports various functionalities: On the one hand, phones can store the context in which users leave registered items and thus help to locate them later on. On the other hand, object owners can search for their objects using the infrastructure of mobile phones carried by other users. We describe the design of our object location system and provide an algorithm which can be used to search for lost or misplaced items efficiently by selecting the most suitable sensors based on arbitrary domain knowledge. Furthermore, we demonstrate the practicability of such wide-area searching by means of user-held sensors in a series of simulations complemented by a real-world experiment.

In this paper, four main types of corrosion: uniform, pitting, crevice and stress corrosion cracking (SCC) found in the petrochemical industry, were characterized and identified by Acoustic Emission (AE) analysis using their locations and extracted AE parameters. A novel low-cost AE location system based on a Field Programmable Gate Array PC (FPGA-PC) and a LOCAN 320 AE analyzer were utilized in this study. Specimens used in experiments were austenitic stainless-steel SS304. The pattern of AE signals from each type of corrosion was plotted using their location and correlation. Experimental results show the ability of our FPGA-PC system to determine corrosion locations. The correlations of AE parameters including amplitude, counts, hits and time were used to identify different types of corrosion. In addition, the characteristics of the corrosion process for each type are explained using the AE signals obtained corresponding to the source locations, together with experimental observation.

A comprehensive review of maximum cloud-to-ground (CG) lightning flash densities observed in the tropical region by different Lightning Location Systems (LLS) is presented. From the observed values, absolute maximum values for a spatial resolution of 1 km × 1 km are estimated, using an empirical curve relating flash density and resolution and correcting the data for differences in the detection efficiency and in the intracloud (IC) contamination of the different LLS. Maximum CG lightning flash densities are compared with total lightning observations by satellite in the same regions, for a spatial resolution of approximately 55 km × 55 km, to infer IC to CG ratios (IC/CG). It was found that absolute maximum CG lightning flash densities in the tropical region vary from 19 to 65 flashes km − 2 year − 1 and IC/CG ratios from 3.9 to 12.6. Absolute maximum CG lightning flash densities and the IC/CG ratios in the tropical region are then compared with similar values in the temperate region. Only the regions corresponding to the highest maximum CG lightning flash densities observed by LLS for each continent in the temperate region are considered. The comparison suggests that higher absolute maximum CG lightning flash densities occur in the tropical region and similar IC/CG ratios occur in both regions, with the exception of Colombia and Venezuela, where this ratio seems to be higher than in any other regions.

We discussed a high accuracy real-time 3D ultrasonic location system in this article. The signal received was sampled after it passed the TGC and the logarithmic amplifier. Inside the DSP, we used the dynamic threshold tracing technique to improve the accuracy. The result was processed with Weighted Arithmetic Average. By testing the 40 kHz 3D location system, we have arrived at the accuracy of 1 cm.

Local locating systems are necessary where a big number of units are handled. In this case, we propose a management system for parking spaces for vehicles that are distributed among eight different-sized lots on a 1.8 million square meter premises. In order to quickly locate each particular vehicle in this area, a new real time location system (RTLS) has been successfully installed. The vehicle location system Moby-R automatically monitors every vehicle movement and tracks its current parked position. All the vehicles are given a data carrier which is attached to the inside rear-view mirror with a special hanger, precisely locating the vehicle within approximately five meters

The Italian Lightning Detection System started at the end of 1994 and has been recording lightning data since then. The efficiency of the whole network is evaluated with the usual projection software. Considering this projection as the real efficiency is possible to weight the calculated ground flash density, getting a much more significant estimation of this fundamental parameter. At the end of 1999 four sensors were added to the network to increase the detection efficiency over the Southern part of the Italian territory and over the main islands of Sardinia and Sicily. An extrapolation of the network upgrade was performed on the previous years of data using the same efficiency correction method. We developed a dedicated software, which takes into account the real behavior of each sensor and calculates the efficiency of the network with this information. The efficiency obtained can be used to correct the ground density map, avoiding holes of efficiency due to temporary sensor problems. After the corrections significant changes in the ground flash density map can be seen, showing some areas of high density that were missed in the usual uncorrected mapping of data. This suggests that influence of Lightning Location System efficiency has to be carefully taken into account in ground flash density calculations.

A new method called focused electrode leak location system (FELL-41) was developed in Europe for identifying potential leaks in sanitary sewers (mainline and service connections at the mainline). The chief advantages of the FELL-41 technology include: (1) identifying leaking joints on mainline during dry weather; (2) prioritising leak repairs by intensity of leaks; (3) determining leaks in service lateral mainline connections; (4) an alternative to air-pressure testing for acceptance of new and rehabilitated sanitary sewers. The FELL-41 method measures electrical current flow between a probe that travels in the pipe and a surface electrode. Pipe defects that allow liquids to flow into or out of the pipe cause a spike in the electrical signal, thereby locating the sources of infiltration or exfiltration. The intensity of the measured current can be correlated to the magnitude of the leaks. The purpose of this paper is to discuss this technology as well as its limitations. The results of the FELL-41 technology will be validated through several case studies.

The enormous benefits of a worldwide accurate location system can only be achieved if GPS and Galileo can be made truly interoperable. The technical issues involved are relatively easy to deal with but the political and legal problems require far greater attention, with military issues and enactment of legislation the chief difficulties. These are discussed using examples, notably from road traffic law. Given that the US DoD is unlikely to cede control of GPS to the civil sector and design a new, separate system, the best solution might be to set aside part of GPS for purely civil purposes.

To assess the feasibility of using an infrared-based Real-Time Location System (RTLS) for measuring patient ambulation in a 2-minute walk test (2MWT) by comparing the distance walked and the Johns Hopkins Highest Level of Mobility (JH-HLM) score to clinician observation as a criterion standard.Criterion standard validation study.Inpatient, university hospital.Patients (N=25) in an adult neuroscience/brain rescue unit.Not applicable.RTLS and clinician-reported ambulation distance in feet, and JH-HLM score on an 8-point ordinal scale.The RTLS ambulation distance for the 25 patients in the 2MWT was between 68 and 516ft. The mean difference between clinician-reported and RTLS ambulation distance was 8.4±11.7ft (2.7%±4.6%). The correlation between clinician-reported and RTLS ambulation distance was 97.9% (P.01). The clinician-reported ambulation distance for 2 patients was +100ft and -99ft compared with the RTLS distance, implying clinician error in counting the number of laps (98ft). The correlation between the RTLS distance and clinician-reported distance excluding these 2 patients is 99.8% (P.01). The accuracy of the RTLS for assessment of JH-HLM score for all 25 patients was 96%. The average patient speed obtained from RTLS data varied between 0.4 and 3.0mph.The RTLS is able to accurately measure patient ambulation and calculate JH-HLM for a 2MWT when compared with clinician observation as the criterion standard.

Bulk patient motion during transthoracic 3-D echocardiography (3DE) produces image plane misregistration and errors in left ventricular (LV) volume and ejection fraction (EF). To correct for patient motion, we used a magnetic locating system to track both the ultrasound transducer and the chest wall of the patient, so images could be registered in a patient-centered coordinate system ("correction"). Fourteen subjects each underwent 3DE, with deliberate patient motion, to measure LV volume and EF. Results were compared to magnetic resonance imaging (MRI). Without correction, 3DE differed significantly from MRI (EF: r = 0.78, SEE = 5.8%). Application of correction increased 3DE accuracy, despite patient motion (EF: r = 0.91, SEE = 3.7%), to a level comparable to that of 3DE in the absence of motion (EF: r = 0.93, SEE = 3.5%). Patient motion during 3DE examination can be corrected using a magnetic spatial location system.

Eurotransplant is an international organ exchange organization which co-ordinates the allocation of donor organs to patients waiting for a transplantation. All transplant programmes in Austria, Belgium, Germany, Luxembourg and The Netherlands collaborate with Eurotransplant. Since its establishment in 1967, circa 70 000 transplantations have been performed through this organization. Currently, more than 15 000 patients are registered on the central waiting list for a kidney, heart, lung, liver or pancreas transplantation. The greatest problem Eurotransplant is facing is the increasing shortage of donor organs. Because of improved transplant results, more patients become transplantable while on the other hand the donor availability has not increased. To deal with this persistent shortage of donor organs, allocation systems have been established with the aim to achieve optimal use of available organs in a transparent and objective way. In Eurotransplant different location systems are being used for the specific organs, mainly based on the current available scientific data in immunology and transplant medicine. Because the success of transplantation is seriously restricted by the shortage of donor organs, a lot of initiatives such as public campaigns, donor cards and donor registries, appointment of transplant co-ordinators and further development of extended hospital donation programmes have been introduced. Although these factors all help, they are so far insufficient to increase the donor supply and insufficient to help all the patients waiting for a transplantation. Alternatives for the usual donor pool should be considered, such as extended donor criteria, non-heart-beating donors and living donation.

Thirty years of experience in shallow water acoustic applications is reviewed in a variety of situations and environments. Particular attention is given to side-looking transducers, applied simultaneously with down-looking ones, in order to estimate fish distributed near the water surface. The success of side-looking operations is primarily limited by transducer and boundary characteristics, requires smooth water conditions but may generate double image echoes as a result of dual acoustic paths. Amongst the various modes of transducer deployment, the side-looking technique has the best spatial coverage but near-boundary detection is best with fixed location, particularly with recently developed remote, automated fixed location systems. Other problems are reviewed.

The Met. Office (UK NMS) has operated a VLF ‘arrival time difference’ thunderstorm location system since 1986. This system's hardware is currently being upgraded and its software enhanced. Hardware improvements will allow the system to operate automatically and increase the number of lightning strokes that may be processed per hour to between 10000 to 12000, improving the system's detection efficiency. Software enhancements will enable flash type (cloud to ground or cloud to cloud), stroke polarity, stroke strength and the number of strokes per event to be determined for lightning occurring over the UK. A VLF propagation model is also being developed to calculate more realistic waveform group velocities with the aim of improving the location accuracy of the system under certain conditions.

A computationally feasible methodology to locate, size, and determine the number of transit centres (bus barns or garages) for an urban transit system is described. This methodology, known by the acronym BUBLS (BUs Barn Location System), is applied to a case study with BC Transit, a large Canadian urban transit system. As the case study illustrates, BUBLS is currently employed in capital projects planning.

With the development of faster and more sophisticated computer hardware, sensor data can be processed at increasing rates. The increased demand on sensors which results can lead to problems with the validity of sensor information. One such effect that can occur with ultrasonic sensors is the reception of second-time-around echoes. These are most likely to be present when observing a target in front of a large reflector. A method used in radar processing to eliminate such interference is described and its application to an ultrasonics phased array object location system is presented.

A special case of the probabilistic multi-locationproblem is studied for deteriorating items. The objective of this study is to determine the location of the minimum number of supply centres among a discrete set of location sites of supply centres under the condition that the probability of each retailer being covered by one of the supply centres is not less than a specified value. A logistic cost function including the deterioration rate is developped for a performance measure of the system. We have formulated a probabilistic set-covering programming which can be solved by a 0–1 programming. The result of a set of numerical examples well shows the impact of deteriorating rate on the location problems. And also this study will provide a method of a useful guidelines for the location decisions.

In this paper, we present a method to locate a normal zone generation point of a short sample of a superconducting wire. In general, in order to locate the point, the voltages across many voltage taps soldered to the sample are measured. However, attaching many voltage taps makes the location system complicated and in a bad case the taps may be short-circuited. In our proposed method, many taps are not needed and precise location can be realized.