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关键词： Accounting information system   Blockchain   COVID-19   Multi-sport event   RFID   Ticketing  

摘要： To run a multi-sport event, it is necessary to have a design of accounting information system for ticket sales that can run efficiently and can reduce opportunities of fraudulent acts. A case study during the 18^th Asian Games 2018 shows that there were problems of inadequate ticket sales facilities for prospective spectators due to vendor diversion to the frictional problems such as venues located in various regions and protection of spectator rights in accordance with the purchased tickets. Some cases found in the multi-sport event were false seats and fictitious spectators allowed entrance to some arenas they did not have the right to enter, although they have gone through verification measures using line-of-sight barcoding technology. Some cases were also found during the 18^th Asian Games 2018, in which there was a problem of inadequate ticket sales facilities for prospective spectators due to a change of vendor. There were also frictional problems on venues which are spread in various regions and regarding protection of spectators’ rights per their purchased tickets. Moreover, it is fundamental that we take concern in the current pandemic situation, all event organizers are obliged to consider implementing health protocols issued by the World Health Organization (WHO) for safety to break the chain of COVID-19 infection. This study is conducted to identify the core of those problems and offer a solution by implementing radio-frequency identification (RFID) and blockchain technology to optimize the services applied in the multi-sport event, especially during and post-pandemic. Ticketing effectiveness for spectators are also challenged by budgetary and eco-friendliness issues. © 2021 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://***/licenses/by/4.0/).

关键词： Antennas   Magnetohydrodynamics   Upper bound   Electromagnetics   Antenna arrays   Radiofrequency identification   Dipole antennas   Antenna arrays   chipless radio frequency identification devices (RFIDs)   RFID   RFID mounted on metal   superdirectivity  

摘要： Cross-polarized backscatterers integrated with a ground plane are a key element of different applications, including chipless RFIDs, sensing, ambient backscattering communications, and data storage. The use of a cross-polarized signal removes the difficulties arising from the strong copolar signal reflected by the ground plane. Concurrently, the cross-polarized signal is typically very weak, hindering the effectiveness of crosspolarized backscatterers in noisy and uncontrolled environments. Herein, the generalized optical theorem is used to derive upper bounds on the cross-polarized backscattering cross section of systems integrated with a ground plane and identify viable strategies to design them based on highly directive scattering systems. Popular antenna configurations, including elementary electric and magnetic dipoles and their combinations, such as Huygens sources and endfire arrays, are examined to ascertain which ones can be used to realize highly directive cross-polarized backscattering performance when they are integrated with a ground plane. Realistic single-antenna elements that attain the upper-bound performance are identified. A two-element endfire array based on crossed electric dipole elements also achieves the upper bound performance, further confirming the efficacy of the derived cross-polarized backscattering bounds.

关键词： Power environmental station   Active UHF transponders   Object monitoring   Bedload   Floating wood   Environmental RFID monitoring station  

摘要： We present a datalogger based on Arduino cards and commercially available tools for radio frequency identification, which we term the e-RFIDuino. Designed to be robut, easy to build and install, it detects and records the mobility of objects tagged with active transponders emitting in the ultra-high frequency domain (433.5 MHz). It functions without connection to the power supply network and is adapted to harsh outdoor environments. Once installed in the field and its on-site sensing field is determined, the data collected (timestamp of detection, transponder identification number, and received signal strength indication) allow estimation of the virtual velocity of tracer passage and investigation of displacement patterns at the scale of the area of detection. Experimental tests showed the device to have very high effectiveness when used to monitor the passage of sediment tracers in a torrential river system during various flood events over several months. The total cost to construct this open source device is below 850 Euros, and it is easily customizable. In the future, it could be equipped with a system for data transmission over the mobile telephone network to reduce the field effort and time required to obtain data, and to provide real-time triggering of field acquisitions at the most appropriate times. (C) 2021 The Authors. Published by Elsevier Ltd.

关键词： textile   radio frequency identification (RFID)   ultra high (UHF) frequency   sucrose solution   concentration   read range   relative dielectric constant  

摘要： With the trend of textile antennas development, ultra high frequency (UHF, 865-868 MHz) radio frequency identification (RFID) devices using textile materials are expected to be developed in many areas for replacing or simplifying some complex RFID devices on a PCB. In this paper, we present a textile UHF-RFID tag with two sensing positions ('radiation parts' and 'loop part') for exploring the feasibility of sucrose solutions measurements and the relationship between variables of the proposed design and the sucrose solutions. The simulated and measured resonance curves of the designs both match well (-20 dB in the simulation and -15.8 dB in the measurement at 868 MHz) and the read range measured by the RFID reader (M6e kit) is 1.71 m in air. Before the tests by the solutions on the proposed designs, a test board is developed as a preparation work for confirming the relative dielectric constants of the sensing substrate area in the real measurements. Compare the results of the simulation and the real tests, the proposed design shows good feasibility by comparing the simulated and measured results in confirmed relative dielectric constants. Moreover, its two sensing positions have different sensing features. The sensing 'radiation parts' position shows a stable frequency operation performance but sensing range is from 1.71 m (dry) to 2.3 m, while the sensing 'loop part' position has a wide sensing range from 0.4 m to 1.71 m (dry) but a lower frequency operation performance.

关键词： Traceability   Food cold-chain   EDI   RFID   Blockchain   Covid-19  

摘要： This study analyzed the traceability system's effect on Indonesia's food cold chain performance during the Covid19 pandemic and described the needs of cold food consumers in Indonesia regarding the traceability system. Five latent variables were used to form research models, including the adoption of electronic data interchange (EDI), radio frequency identification (RFID), blockchain, traceability system, and food cold chain performance. This study uses a quantitative approach with a questionnaire as a research instrument distributed to 140 respondents by purposive sampling. The total number of manifest variables measuring latent variables is 28 variables. A partial least square for structural equation modeling (PLS-SEM) is used to analyze the relationship between latent variables. The results obtained through this study are that exogenous variables: EDI, RFID, and blockchain adoption, significantly affect endogenous variables, namely the traceability system. Blockchain adoption is proven to have a very significant influence compared to the three information technologies. This work also confirms that the traceability system also has a significant effect on food cold chain performance.

关键词： chipless radio frequency identification (RFID)   interdigital capacitor (IDC) structure   humidity sensing   polyvinyl alcohol (PVA)   radar cross-section (RCS)  

摘要： An eight-bit chipless radio frequency identification tag providing humidity sensing and identification information is proposed. A compact, enhanced-sensitivity resonator based on an interdigital capacitor (IDC) structure is designed for humidity sensing, whereas seven electric-field-coupled inductor capacitor (ELC) resonators are used for identification information. These eight resonators are placed in a two-by-four array arrangement. A step-by-step investigation for the effect of varying the number of elements and array configuration on the resonant frequency and radar cross-section (RCS) magnitude of the IDC resonator is conducted. The RCS value of the resonant peak frequency for the IDC resonator increases as the number of array elements placed nearby increases due to the mutual coupling among the elements, and the increase in the RCS value becomes larger as the number of arrays increases in the vertical direction. Polyvinyl alcohol (PVA) is coated on the IDC-based resonator at a thickness of 0.02 mm. A non-reflective temperature and humidity chamber is fabricated using Styrofoam, and the relative humidity (RH) is varied from 50% to 80% in 10% intervals at 25 & DEG;C in order to measure a bistatic RCS of the proposed tag. The humidity sensing performance of the IDC resonator in the proposed tag is measured by the shift in the resonant peak frequency and the RCS value, and is compared with a single ELC resonator. Experiment results show that when RH increased from 50% to 80%, the sensitivities of both the resonant peak frequency and the RCS value of the IDC resonator were better than those of the ELC resonator. The variation in the RCS value is much larger compared to the resonant peak frequency for both IDC and ELC resonators. In addition, the resonant peak frequency and RCS value of the PVA-coated IDC-based resonator change, whereas those of the other seven resonators without a PVA coating do not change.

关键词： Dipole antennas   Magnetic circuits   Magnetic resonance   Radiofrequency identification   Integrated circuit modeling   Bandwidth   Equivalent circuits   Chu-limit   circular polarization (CP)   electrically small antenna (ESA)   magnetic dipole antenna   metamaterial-inspired antenna   RFID   split-ring resonator (SRR)  

摘要： A novel electrically small, wide beamwidth circularly polarized (CP) antenna using two orthogonal smaller hybrid magnetic dipoles (HMDs) for radio frequency identification (RFID) reader application is presented, which achieves a quality factor ( $Q$ -factor) approaching the Chu-limit. First, a HMD is implemented by the combination of two single-slit magnetic dipoles (S-MDs) and one dual-slit magnetic dipole (D-MD), which is carefully analyzed by equivalent circuit models and field distribution. Then, by implementing two orthogonal HMDs with slightly size difference and a 45 degrees angle tilted coupling feeding line, two orthogonal magnetic components with equal magnitude and 90 degrees phase difference are obtained, which lead to a CP radiation. Finally, an electrically small CP magnetic dipole antenna with a size of 0.12 lambda(0) x 0.12 lambda(0) x 0.04 lambda(0)(ka < 0.55) (lambda(0) is the free-space wavelength at its center frequency) is fabricated and measured. The measurement shows that a -10 dB impedance bandwidth of 3.17% (cover 902-928 MHz UHF band well), a half power beamwidth (HPBW) of 104 degrees, and a peak radiation gain of 4.57 dBic are achieved. Generally, it features a small size, wide beamwidth, simple design, and good radiation performance, exhibiting good application potential usage in internet of things (IoTs) systems.

关键词： Multi resonators   Multi-scatterer based tags   Radar cross-section (RCS)   Radio frequency identification (RFID)   RFID tags  

摘要： A Flower Shaped Frequency Coded Chip-less RFID Tag with a fully printable and polarization-independent tag is discussed in this paper. The tag encodes a data capacity of 12 bits. The data is encoded and transmitted using the RF encoding particle technique in the spectral domain as a frequency signature of the resonators. The proposed 12-bit tag covers the spectral range from 8 to 11.5 GHz. The tag is designed and simulated using CST Microwave Studio software. The low-cost FR-4 substrate is used for simulation with the dielectric constant of 4.3 and tangent loss of 0.018. This compact tag occupies only 13 mm x 13 mm area, hence can be printed cheaply on one side substrates.

关键词： Radio frequency identification (RFID)  

摘要： Radio Frequency Identification (RFID) systems are among the most widespread computing technologies with technical potential and profitable opportunities in numerous applications worldwide. Further, RFID is the core technology behind the Internet of Things (IoT), which can accomplish the real-time transmission of information between objects without manual operation. However, RFID security has been taken for granted for several years, causing multiple vulnerabilities that can even damage human functionalities. The latest ISO/IEC 18000-63:2015 standard concerning RFID dates to 2015, and much freedom has been given to manufacturers responsible for making their devices secure. The lack of a substantial standard for devices that implement RFID technology creates many vulnerabilities that expose end-users to elevated risk. Hence, this paper gives the reader a clear overview of the technology, and it analyzes 23 well-known RFID attacks such as Reverse Engineering, Buffer Overflow, Eavesdropping, and Malware. Moreover, given the exceptional capabilities and utilities of RFID devices, this paper has focused on security measures and defenses for protecting them, such as Active Jamming, Shielding tag, and *** Codes 68M25 © 2021, CC BY.