Search

Radio-frequency identification is one of the Internet of Things’ most promising technologies and has been recently used in combination with mobile robots for logistics in business and retail applications. This manuscript deals with the localization of passive UHF RFID tags within industrial environments employing receiving antennas mounted on a mobile robot by using multilateration techniques that exploit narrowband phase-delay measurements. Two distinct Particle Filter approaches are presented to solve the 3D multilateration problem online and take advantage of a synthetic aperture created by the motion of the robot in the environment. One of the methods can operate in the presence of acquisition jumps since it does not rely on an unwrapping technique. Experimental results show promising performance concerning the recent literature. Moreover, the presented approach enables robust estimations concerning signal loss due to communication disturbances in noisy environments, typical of the industrial setting.

Abstract This paper aims to analyze the text of Luke 17:11-19 about the ten lepers from the perspective of People Living with HIV/AIDS (PLWHA) in Maumere. The author conducts this research by using qualitative method. The data is taken from depth interviews and participatory observation at Flores Plus Support-Maumere Peer Support Group (KDS). By using a reader-oriented approach, this paper analyzed the experiences of PLWHA and their perspectives on the account of the ten lepers. The findings showed that for HIV survivors in Maumere, peer groups play an important role in raising their hopes in the midst of high rate of stigma and discrimination. In the eyes of PLWHA, the role of KDS can be juxtaposed with the “group” of the ten lepers in Luke’s story. Abstrak Artikel ini bertujuan untuk menganalisis teks Lukas 17:11-19 tentang kesepuluh orang kusta dari perspektif Orang dengan HIV/AIDS (ODHA) di Maumere. Untuk membahas masalah ini penulis melakukan penelitian kualitatif dengan wawancara mendalam dan observasi partisipatoris di Kelompok Dukungan Sebaya (KDS) Flores Plus Support-Maumere. Dengan menggunakan pendekatan reader oriented artikel ini menganalisis pengalaman para ODHA dan sudut pandang mereka tentang kisah kesepuluh orang kusta. Hasil penelitian ini menunjukkan bahwa, bagi para ODHA di Maumere, kelompok sebaya memainkan peran penting untuk membangkitkan harapan mereka di tengah tingginya stigma dan diskriminasi. Dalam kacamata para ODHA, peran KDS dapat dibandingkan dengan “paguyuban” sepuluh orang kusta dalam kisah Lukas.

Tujuan penelitian ini adalah untuk menganalisis efek eko-enzim terhadap produksi telur, fertilitas, daya tetas ayam IPB-D1. Ayam yang digunakan dalam penelitian ini yaitu sebayak 96 ekor (72 betina dan 24 jantan). Metode yang digunakan adalah Rancangan Acak Lengkap (RAL) yang terdiri dari 4 perlakuan dan 6 ulangan, tiap ulangan ada 4 ekor ayam (1 jantan, 3 betina). Perlakuan yang diberikan yaitu: P1 = air minum tanpa eko-enzim (kontrol), P2 = 1 cc eko-enzim/L air minum / 3 hari, P3 = 2 cc eko-enzim/L air minum /3 hari, P4 = 3 cc eko-enzim/L air minum/ 3 hari. Jumlah telur yang digunakan untuk mengamati kualitas telur yaitu sebanyak 72 butir, 6 butir tiap perlakuan, dan 3 ulangan. Hasil analisis statistik berpengaruh nyata (P

This paper presents a state-of-the-art analysis on the methods suitable for vehicle indoor localization and exploiting the RFID (Radio Frequency IDentification) technology. The survey describes three main categories of vehicle localization systems: (i) solutions exploiting only the RFID technology, (ii) sensor-fusion techniques combining data from RFID systems and proprioceptive sensors, and (iii) sensor-fusion techniques combing RFID data with those of other exteroceptive sensors in addition to the RFID system itself. For each method, implementation and methodological details are discussed, by highlighting the applied RFID technology, namely passive HF-RFID, passive UHF-RFID, or any other RFID system. Also, the employed RFID parameters, i.e., tag EPC, RSSI or backscattered phase, are discussed. The survey focuses on the achievable localization performance, also accounting for infrastructure-deployment costs together with complexity and maintenance overhead. Positioning, tracking, navigation and simultaneous localization and mapping (SLAM) issues are here considered. The analysis highlights pros and cons of each method, together with the main challenges and perspectives of RFID-based solutions for vehicle localization.

A dual circularly polarized (CP) stacked patch antenna for Multiple-Input Multiple-Output (MIMO) WLAN applications (2.4-2.485 GHz) is presented, which exploits a square ring slot feeding technique. The antenna occupies an overall area of 96 mm x 96 mm x 39 mm, when also including the metal reflector. The 7-dBic gain antenna prototype presents an axial ratio lower than 2.5 dB as well as a port isolation higher than 25 dB. An envelope correlation coefficient (ECC) lower than 0.02 is also achieved among the two ports, thanks to the polarization orthogonality. Moreover, the stacked patch has been duplicated and used in a two-antenna system for a 4 x 4 MIMO WLAN which fits an overall volume of 157 mm x 96 mm x 39 mm. Antenna performance in terms of S-Parameters, gain, axial ratio, ECC and channel capacity are compared and discussed, together with the effect of the inter-element distance.

This paper investigates the focusing features of a multi-panel near-field focused (NFF) antenna. Differently from conventional NFF planar arrays, the proposed configuration is made of a set of NFF subarrays that are concentrically arranged over a cylindrical boundary. A systematic numerical analysis is performed to show how to control the shape of the -3dB focal spot through the main geometrical and electrical parameters of the proposed antenna layout, such as the number of subarrays, the focal spot location of each subarray and the radius of the cylindrical boundary the subarrays are arranged on. When compared with conventional planar NFF arrays, the additional mechanical complexity is partially balanced by a simpler feeding network design and a more symmetric focal spot. Experimental results are shown for a prototype operating at the 2.4 GHz ISM band.

A compact, low-profile, two-port dual-band circularly polarized (CP) stacked patch antenna for radio-frequency identification (RFID) multiple-input-multiple-output (MIMO) readers is proposed, which employs the shared-aperture technique. The proposed antenna adopts a 1.524 mm thickness Rogers Ro4350b substrate with relative permittivity of 3.48. Two pairs of isolated ports are working at two microwave- (MW-) RFID bands (2.4–2.485 GHz and 5.725–5.875 GHz) with high port isolation of 25 dB and 30 dB, respectively. A shared metal slot layer is designed to separate two feeding structures of the lower band and upper band for port isolation enhancement as well as saving space. Corner-truncated square slot and patch configurations have been designed to obtain CP modes. In the lower and upper MW-RFID bands, the relative impedance bandwidths are 12.2% and 5.7%, and the maximum realized gains are higher than 7.3 dBic. Moreover, two-element configurations have been combined for an RFID MIMO system that occupies a dimension of 119 mm × 119 mm × 12.9 mm. The MIMO antenna performance of envelope correlation coefficient (ECC) is lower than 0.03, and diversity gain is close to 10 dB.

This article addresses the problem of determining the location of pallets carried by forklifts inside a warehouse, which are recognized thanks to an onboard Radio Frequency IDentification (RFID) system at the ultra-high-frequency (UHF) band. By reconstructing the forklift trajectory and orientation, the location of the pallets can be associated with the forklift position at the time of unloading events. The localization task is accomplished by means of an easy-to-deploy combination of onboard sensors, i.e., an inertial measurement unit (IMU) and an optical flow sensor (OFS), with a commercial ultra-wideband (UWB) system through an Unscented Kalman Filter (UKF) algorithm, which estimates the forklift pose over time. The proposed sensor fusion approach contributes to the localization error mitigation by preventing drifts in the trajectory reconstruction. The designed methos was at first evaluated by means of a simulation framework and then through an experimental analysis conducted in a large warehouse with a size of about 4000 m2.

The I-READ 4.0 project is aimed at developing an integrated and autonomous Cyber-Physical System for automatic management of very large warehouses with a high-stock rotation index. Thanks to a network of Radio Frequency Identification (RFID) readers operating in the Ultra-High-Frequency (UHF) band, both fixed and mobile, it is possible to implement an efficient management of assets and forklifts operating in an indoor scenario. A key component to accomplish this goal is the UHF-RFID Smart Gate, which consists of a checkpoint infrastructure based on RFID technology to identify forklifts and their direction of transit. This paper presents the implementation of a UHF-RFID Smart Gate with a single reader antenna with asymmetrical deployment, thus allowing the correct action classification with reduced infrastructure complexity and cost. The action classification method exploits the signal phase backscattered by RFID tags placed on the forklifts. The performance and the method capabilities are demonstrated through an on-site demonstrator in a real warehouse.

Autonomous vehicles enable the development of smart warehouses and smart factories with an increased visibility, flexibility and efficiency. Thus, effective and affordable localisation methods for indoor vehicles are attracting interest to implement real-time applications. This paper presents an Extended Kalman Smoother design to both localise a mobile agent and reconstruct its entire trajectory through a sensor-fusion employing the UHF-RFID passive technology. Extensive simulations are carried out by considering the smoother optimal-window length and the effect of missing measurements from reference tags. Monte Carlo simulations are conducted for different vehicle trajectories and for different linear and angular velocities to evaluate the method accuracy. Then, an experimental analysis with a unicycle wheeled robot is performed in real indoor scenario, showing a position and orientation root mean square errors of 15 cm, and 0.2 rad, respectively.

This paper provides a review spanning different technologies used to implement near-field focused antennas at the microwave frequency band up to a few tens of GHz: arrays of microstrip patches and printed dipoles, arrays of dielectric resonator antennas, reflectarrays, transmitarrays, Fresnel zone plate lenses, leaky-wave antennas, and waveguide arrays.

An overview on compact Planar Inverted-F Antennas (PIFAs) that are suitable for monitor-equipped devices is presented. In particular, high efficiency PIFAs (without any dielectric layer) with a percentage bandwidth (%BW) greater than 59% (470–862 MHz DVB-T band) are considered. In this context, two PIFA configurations are reviewed, where a dual-band feature has been obtained, in the 3300–3800 MHz (14% percentage bandwidth) WiMAX and 2400–2484 MHz (2.7% percentage bandwidth) WLAN IEEE 802.11b,g frequency bands, respectively, to also guarantee web access to on-demand services. The two PIFAs fill an overall volume of mm3 and mm3, respectively. They are composed of a series of branches, properly dimensioned and separated to generate the required resonances. Finally, to show the extreme flexibility of the previous two configurations, a novel dual-band L-shape PIFA has been designed. A reflection coefficient less than −6 dB and −10 dB and an antenna gain of around 2 dBi and 6.3 dBi have been obtained in the 470–862 MHz DVB-T band and the 2400–2484 MHz WLAN band, respectively. The L-shape PIFA prototype can be obtained by properly cutting and folding a single metal sheet, thus resulting in a relatively low-cost and mechanically robust antenna configuration.

A cylindrical dielectric resonator antenna is proposed as a radiator for an active integrated antenna. Harmonic tuning, which is the key step in designing active antenna radiators, is achieved via a combination of shape factor control over the resonator and insertion of reactive elements in the feed system. Numerical simulations are carried out in a finite elements framework and a layout for the complete antenna is proposed, aimed at compactness for subsequent utilization of the radiator as an element in an active array for satellite communications.

A slot-coupled rectangular dielectric resonator antenna (DRA) operating in the 14–14.5 GHz frequency band is investigated as a possible radiating element for an active integrated antenna of a transmitting phased array. The effectiveness of the resonator shape factor on achieving harmonic tuning is addressed. Simulation results show that the DRA shape factor can be used to provide a fine tuning of the DRA input impedance both at the fundamental frequency and its first harmonics, so synthesizing the proper load for the optimization of the microwave amplifier power-added efficiency (PAE).

Although many scholars have examined the history and culture of the first United States-hosted World's Fair, little coverage has been given to the various items and products that comprised its foodscape. To that end, this paper considers the creation of and engagement with the food and drink provided to fairgoers at the 1876 Centennial Exposition held in Philadelphia. In addition to superlatives in technology, architecture, and other pursuits, planners and purveyors of the fair described the event as the first to showcase food and drink from around the world. By examining menus, newspaper and magazine articles, tour guides, personal recollections, and other ephemera, I will show that the Centennial foodscape earned more detraction than praise for a variety of historical and cultural reasons. Those reasons include economic constraints, sanitary issues, geographic limitations, and difficulties in exposing the average American fairgoer to new or unfamiliar ingredients and recipes. [ABSTRACT FROM AUTHOR]