GPS tracking reveals complex resource acquisition strategies of pastoralists in East Africa

Silvopastoral systems of the Chol Mayan ethnic group in southern Mexico: Strategies with a traditional basis

We distributed a 16-question survey concerning noxious weed abundance, impacts, and management to livestock producers grazing on privately owned or leased grazing lands in Montana. The noxious weeds most commonly reported as being present on respondents’ grazing units were Canada thistle [Cirsium arvense (L.) Scop.] (64% of grazing units) and leafy spurge (Euphorbia esula L.) (45% of grazing units), and these species also reportedly caused the greatest reductions in livestock forage. Houndstongue (Cynoglossum officinale L.) was more prevalent than either spotted knapweed (Centaurea stoebe L.) or diffuse knapweed (Centaurea diffusa Lam.) (39% vs. 32% and 10%, respectively, of grazing units), but collectively C. stoebe and C. diffusa were reported to cause greater forage reductions than C. officinale. The top three strategies used to manage noxious weeds were chemical control, grazing, and biological control. Combining survey responses with forage-loss models derived from field data for C. stoebe and E. esula, we estimated the combined cost of noxious weed management and forage losses on privately owned rangeland to be $3.54 ha−1 yr−1, or $7,243 annually for an average size grazing unit (i.e., 2,046 ha [5,055 ac]). Our estimates of economic losses are lower than many estimates from previous studies, possibly because we focused only on direct costs related to private grazing land, while other studies often consider indirect impacts. Nonetheless, our estimates are substantial; for example, our estimated loss equates to 24% of the average per-hectare lease rate for Montana grazing land.

ABSTRACTElectronic monitoring has recently entered a new phase in Belgium by introducing it at the pre-trial stage. In fact, Global Positioning System (GPS) tracking, as supportive technology, has potentially replaced remand custody. From a controlling perspective, GPS tracking is perceived to be remarkable as it allows constant monitoring of subjects’ movements in real time. However, this crucial advantage of GPS tracking is heavily underused in Belgium. This article describes the advent of GPS tracking in Belgium by situating it within broader penal policy and the existing application of electronic monitoring in Belgium. The application and management of GPS tracking will also be explained and its possible advantages and drawbacks discussed.

A survey of bovine cysticercosis/human taeniosis in Northern Turkana District, Kenya

Shaping the Herders' "Mental Maps": Participatory Mapping with Pastoralists' to Understand Their Grazing Area Differentiation and Characterization.

Introduction: An estimated 20 million people are victims of human trafficking around the world annually. In the United States, human trafficking is a federal crime under the Victims of Trafficking and Violence Protection Act of 2000. US studies have shown that up to 88% of human trafficking victims seek medical care. Therefore, as physicians we have a unique opportunity to recognize these acts and potentially intervene. The human gastrointestinal cavity is often used for illegal purposes, such as narco-trafficking leading to foreign body ingestion. We present a unique case of a 28-year-old female who was a sex trafficking victim and presented to the hospital after she was forced to swallow two global positioning system (GPS) trackers by her traffickers. Case Description/Methods: A 28-year-old female with history of seizures, presented to the emergency department with 1 week of hematemesis. She reported that she was a human trafficking victim, forced to swallow two GPS trackers 8 days prior. Blood pressure was 106/72, pulse 67, temperature 97.8 °F. Physical examination was negative for abdominal tenderness or distention. Hemoglobin was 10.1 g/dL. CT scan of abdomen and pelvis showed two metallic disc shaped objects in the gastric antrum measuring 2.1 × 0.6 cm each. The gastroenterology team was consulted and performed an urgent esophagogastroduodenoscopy. At EGD, 2 “TILE” tracking GPS devices were found in the antrum, and were removed with Roth net without complication. The social work team was involved, and the retrieved objects were transferred to Homeland Security. Prior to further investigation, the patient left against medical advice, without subsequent return (Figure). Discussion: To our knowledge, this is the first reported case of endoscopic removal of GPS trackers from a patient’s stomach in the US. This case highlights use of GPS devices for malicious purposes and the clinical challenges posed for healthcare providers. Human trafficking is underrecognized in medicine due to the associated legal and social stigma, with women, children, and financially challenged populations being more likely targets. Victims may not disclose any history of abuse due to fear of retribution. Physicians should have a high level of suspicion when potentially encountering such patients as one interaction and physician intervention may be potentially life-altering or lifesaving for victims of human trafficking.Figure 1.: Two GPS trackers in the gastric antrum.

The Global Positioning System (GPS) has played a major role in weapons test and evaluation (T&E) since the early 1980s. Such use of GPS is becoming even more widespread on the T&E ranges in the 1990s. The reason for this continued use of GPS is that it has many advantages over other available range tracking techniques. ADVANTAGES OF GPS FOR RANGE TRACKING Since GPS is a satellite-based tracking system, and the distance measurement from satellites in space decides the position of the players, it requires no ground reference. The position accuracy is determined only by the accuracy to which the position of the satellites is known and our ability to measure the distance from the satellites to the player. It has nothing to do with the location of the player anyplace in the world. GPS precision code accuracy is about 50 feet for nondifferential operation and in the vicinity of 6feet when differential techniques are used, depending upon the relative position of the satellites used for position determination. The position of the player can be found to 50 feet or better despite his location. Other tracking techniques such as radar, trilateration, phototheodolites, and lasers have excellent position accuracy under certain conditions. However, these accuracies depend upon the player's position in relation to the tracking device. At extended ranges and very low tracking angles, for example, the accuracy of these tracking devices deteriorates drastically. This ability to determine accurate player position in any location is the significant advantage of GPS over alternate tracking systems. Distance from the base or tracking site has nothing to do with the accuracy of player determination. The other significant advantage of GPS for range tracking applications is that it is capable of providing position location to an unlimited number of players simultaneously. These two advantages of GPS are the main reason that GPS is the preferred method for time-space-position information (TSPI) determination in weapons test and evaluation. These advantages can be realized to their maximum extent in operational test and evaluation where operations involving many players take place over extended range areas. IMPLEMENTATION OF GPS In using GPS for target tracking, there are two principal methods in which it may be applied. First, a GPS receiver may be installed aboard the vehicle where its exact location is determined. Thus each vehicle knc .lls its precise position. This position information mdy then be recorded on the vehicle or sent by data link to a ground station. The other method of implementation is to receive the satellite signals on board the vehicle and retransmit them to the ground where the vehicle position is determined. Each of these techniques has its own advantages. A GPS receiver-data link system is usually larger than a GPS frequency translator. A translator system is therefore selected for very small vehicles such as missiles. Where GPS receiver acquisition time may be a few seconds, a GPS frequency translator processing system working with a GPS reference receiver can provide precise player position within a second of signal acquisition. This rapid acquisition time is mandatory when using GPS tracking for missile range safety. A GPS receiver-data link system, however, has the advantage of deciding position aboard the player and is the preferred system for aircraft tracking. Between these two GPS system implementations, an optimum solution can be selected for almost any range tracking problem. PACKAGING OF AIRBORNE GPS SYSTEMS FOR TEST APPLICATIONS For most test applications, the GPS hardware is temporarily added to the vehicle under test. For fighter aircraft the GPS hardware is generally installed in a pod mounted at a wing weapon pylon. These pods are the same weight and dimension as an AIM-9 missile that is mounted on the pylon. The addition of the test instrumentation thus does not cause any difference in performance of the test vehicle. For larger aircraft the GPS instrumentation is located on a plate that is internally installed. These plate installations have also been used in helicopters. For special installations on ships, these systems have been installed in small drums attached to the mast. All these applications have been for the temporary installation of test instrumentation. When GPS navigation systems are installed aboard all vehicles, a separate GPS instrumentation system will not be needed. When these GPS navigation systems are normally installed on the test vehicles and are coupled to a data bus and precise position data is available throughout the test vehicle, installing special instrumentation GPS will not be necessary. We estimate that this data will be available aboard all vehicles in about 10 years. APPLICATION OF GPS FOR TEST AND EVALUATION GPS was first used for test and evaluation on the U.S. Navy's fleet ballistic missile (FBM) program in the early 1990s. The Trident, a long-range missile, was to be tested farther at sea, and more than one could be in the air at once. The existing range tracking systems were not adequate for range safety and metric tracking. Interstate Electronics Corporation then developed a GPS tracking system for the Trident program. This was a GPS frequency translator system with a translator located on the missile. This translator received the L-band signals from all satellites in view, shifted the frequency to S-band, and retransmitted them to a ground-based translator processing system. The translator processing system, with fast signal acquisition capability, produced a state vector of the missile trajectory used by the range safety officer. In addition precise tracking information is used for guidance system evaluation. Because of the success of GPS on the Trident program, other range tracking requirements were considered for GPS application. In the mid-1980s the U.S. Department of Defense directed a study of the tracking requirements on all U.S. ranges to see if GPS offered a practical solution. The results of this study showed that 95 percent of the range tacking requirements could be satisfied with GPS and that GPS was more cost effective than alternate tracking techniques. The Air Force was then directed to develop a family of GPS instrumentation hardware for the test and training community. lnterstate Electronics was selected to perform the development of these GPS instrumentation systems. A whole family of GPS hardware and associated systems were developed. A system consisted of an instrumentation pod containing a P-code GPS receiver, an inertial reference unit, a data link transceiver, GPS and data link antennas, and an encryption device (see figure 1). This pod-mounted equipment was also furnished on a plate for internal aircraft and helicopter mounting (see figure 2). A complete data link receiving station and GPS reference station were also developed to support the airborne equipment (see figure 3). A new, smaller GPS frequency translator was then developed for reentry vehicle application along with a new ground-based translator processing system (see figures 4 and 5). These systems were applied to a variety of applications. The pod-mounted systems have been used for fighter aircraft test and evaluation such as the F-16 upgrade program at Edwards Air Force Base. The plates have been used on helicopters, transport aircraft, and small commercial aircraft for test and evaluation. In a special application one of our pod-mounted GPS receivers and an inertial reference unit was used to guide a 2,000-pound bomb to a preselected target from an altitude of approximately 30,000 feet and 16 miles downrange from the target with amazingly successful results. The GPS frequency translators were used to test the Strategic Defense Initiative (SDI) program's ERlS (exoatmospheric reentry-vehicle interception subsystem. In this application an ERlS interceptor was fired from the Kwajalein Atoll to intercept a reentry-vehicle fired on a Minuteman missile installed in both the interceptor and the reentry vehicle. From these various types of applications, the versatilityof GPS as a precise TSPl instrumentation device for weapon system test and evaluation is exhibited. THE FUTURE OF GPS IN TEST AND EVALUATION Because of its relatively high accuracy and its ability to track many vehicles simultaneously over an extended range area, GPS is becoming the desired TSPl source for the test and evaluation of weapon systems. As we look to the T&E requirements of the future, with more exotic weapons and platforms, the full advantage of GPS will be appreciated. These advantages will become more and more apparent as much larger range areas are required for the testing of long-range, high-velocity weapons and the number of weapons and targets to be simultaneously tracked is increased. GPS has earned its place in the T&E community and will be in even more demand in the future. Figure 1. Instrumentation Pod Containing a P-Code GPS Receiver, an Inertial Reference Unit Data Link Transceiver, Antennas, and an Encryption Device Figure 2. Plate Used for Internal Aircraft and Helicopter Mounting Figure 3. Complete Data Link Receiving Station and GPS Reference Station Figure 4. Small GPS Frequency Translator for Reentry Vehicle Application Figure 5. Ground-Based Frequency Translator System

From grazing units to milking units: The gendered nature of intra-household livestock management and food security for pastoralists in Kenya

Feasibility and acceptability of mobile methods to assess home and neighborhood environments related to adolescent sleep

BackgroundTracking individuals in environmental epidemiological studies using novel mobile phone technologies can provide valuable information on geolocation and physical activity, which will improve our understanding of environmental exposures.ObjectiveThe objective of this study was to assess the performance of one of the least expensive mobile phones on the market to track people's travel-activity pattern.MethodsAdults living and working in Barcelona (72/162 bicycle commuters) carried simultaneously a mobile phone and a Global Positioning System (GPS) tracker and filled in a travel-activity diary (TAD) for 1 week (N=162). The CalFit app for mobile phones was used to log participants’ geographical location and physical activity. The geographical location data were assigned to different microenvironments (home, work or school, in transit, others) with a newly developed spatiotemporal map-matching algorithm. The tracking performance of the mobile phones was compared with that of the GPS trackers using chi-square test and Kruskal-Wallis rank sum test. The minute agreement across all microenvironments between the TAD and the algorithm was compared using the Gwet agreement coefficient (AC1).ResultsThe mobile phone acquired locations for 905 (29.2%) more trips reported in travel diaries than the GPS tracker (P<.001) and had a median accuracy of 25 m. Subjects spent on average 57.9%, 19.9%, 9.0%, and 13.2% of time at home, work, in transit, and other places, respectively, according to the TAD and 57.5%, 18.8%, 11.6%, and 12.1%, respectively, according to the map-matching algorithm. The overall minute agreement between both methods was high (AC1 .811, 95% CI .810-.812).ConclusionsThe use of mobile phones running the CalFit app provides better information on which microenvironments people spend their time in than previous approaches based only on GPS trackers. The improvements of mobile phone technology in microenvironment determination are because the mobile phones are faster at identifying first locations and capable of getting location in challenging environments thanks to the combination of assisted-GPS technology and network positioning systems. Moreover, collecting location information from mobile phones, which are already carried by individuals, allows monitoring more people with a cheaper and less burdensome method than deploying GPS trackers.

Global Positioning System (GPS) tracking is a common tool used to prevent and handle situations where people with dementia get lost. Based on ethnographic fieldwork at a Danish, public nursing home, we explore the use of GPS tracking in everyday dementia care from the perspective of care workers. GPS tracking is a technology that promises a type of effortless and safety-enhancing surveillance. Meanwhile, our observations indicate that GPS tracking in everyday care situations depends entirely on care workers attending to the technology in physical and relational ways. Our analysis highlights how the technology in that process is re-shaped from a promise of smooth surveillance to a reality of hard-earned glimpses into the location of residents wearing the trackers. Drawing on the terms maintenance and repair work, we argue that care workers use GPS tracking with a high fidelity to the idea of the technology as safety-enhancing, and that this motivates the ongoing attention and adjustments necessary to make the technology function. We contribute to STS scholarship on the necessary, local adjustments of technologies by suggesting that efforts to make technology work in practice can be fueled by a technology's goals and expectations rather than stand in contrast to them.

Microhabitat and patch selection detection from GPS tracking collars of semi-free ranging Mashona cattle within a semi-arid environment

Safer transportation of school children has been a critical issue nowadays as children are prone to abductions, accidents and, etc. This paper aims to present an efficient system called GRAG - (GPS, RFID and GSM) for the safety of the school children. In GRAG, radio frequency identification (RFID) will monitor the entry and the exit of children into and out of the school respectively. Messages will be sent to parents regarding the same using short message service (SMS). In case, the child does not reach the school or home within the time period, parents can call the registered number placed in the global positioning system (GPS) tracker to activate it. Then, the GPS tracker will track the position, the latitude and longitude coordinates of the child and are sent to the parent's mobile. These coordinates can be entered into the Android application to find the exact location.

Simple SummaryMonitoring changes in the utilization of forages across rangelands can be time consuming and difficult with untrained personnel. The use of real time positioning for cattle is becoming commercially available with the improvements in technology. The objective of this case study was to identify the changes in livestock social associations and spatial location at two stocking densities throughout a six-week grazing period. Both pastures used similar sized herds with 35 and 29 animals tracked with global positioning systems set at 30-min intervals. A half-weight index value was calculated for each pair of tracked cattle to determine the proportion of time that cattle were within 75 m and 500 m of each other. Throughout the study, forage utilization increased from 5 to 24% and from 10% to 20% and forage mass decreased from 2601 kg ha−1 to 1828 kg ha−1 and 2343 kg ha−1 to 1904 kg ha−1, in the high stocking density pasture and low stocking density pasture, respectively. Utilization of forages throughout the trial forced cattle to disperse and travel further from water sources to find new feeds. Real-time GPS tracking has the potential to remotely detect changes in animal spatial association, identify when cows disperse, and improve recognition for the need of pasture rotation to avoid rangeland degradation.Proper grazing management of arid and semi-arid rangelands requires experienced personnel and monitoring. Applications of GPS tracking and sensor technologies could help ranchers identify livestock well-being and grazing management issues so that they can promptly respond. The objective of this case study was to evaluate temporal changes in cattle association patterns using global positioning system (GPS) tracking in pastures with different stocking densities (low stocking density [LSD] = 0.123 animals ha−1, high stocking density [HSD] = 0.417 animals ha−1) at a ranch near Prescott, Arizona. Both pastures contained similar herd sizes (135 and 130 cows, respectively). A total of 32 cows in the HSD herd and 29 cows in the LSD herd were tracked using GPS collars at location fixes of 30 min during a 6-week trial in the summer of 2019. A half-weight index (HWI) value was calculated for each pair of GPS-tracked cattle (i.e., dyads) to determine the proportion of time that cattle were within 75 m and 500 m of each other. Forage mass of both pastures were relatively similar at the beginning of the study and forage utilization increased from 5 to 24% in the HSD pasture and increased from 10 to 20% in the LSD pasture. Cattle in both pastures exhibited relatively low mean association values (HWI < 0.25) at both spatial scales. Near the end of the study, cattle began to disperse likely in search of forages (p < 0.01) and travelled farther (p < 0.01) from water than during earlier periods. Real-time GPS tracking has the potential to remotely detect changes in animal spatial association (e.g., HWI), and identify when cows disperse, likely searching for forage.

Traditionally, demographic monitoring of birds has been undertaken by intensive monitoring of nesting sites. However, this is challenging for low-density species, whereby the effort and costs involved in locating and monitoring remote sites can be prohibitive or even bias research findings. We show that Global Positioning System (GPS) tracking can overcome these challenges for a low-density raptor. Field monitoring of martial eagles Polemaetus bellicosus from 2013 to 2021 showed consistently poor breeding performance, with a mean productivity of 0.22 (±0.04) fledged young/pair/year. Using GPS tracking data to infer breeding performance gave a significantly higher productivity of 0.46 (±0.10) fledged young/pair/year. Breeding rate and success were also underestimated by field monitoring. These differences were likely due to logistical constraints of field monitoring, particularly relating to finding alternative nests. Comparing costs between approaches, we estimated that GPS monitoring was financially cheaper than field monitoring per sample after 10 years. Carbon costs per sample were lower for GPS-based approaches than field monitoring from the second year, and over a 10-year period GPS monitoring produced considerable savings (200% less carbon). We recommend that despite high initial costs, for long-term demographic monitoring of low-density species, or where logistical constraints make traditional field monitoring inaccurate, remote monitoring options should be considered.