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The purpose of this paper is to develop a novel totally passive, wireless temperature sensor tag based on ultra high-frequency (UHF) radio frequency identification (RFID) technology. The temperature-sensing functionality is enabled by using distilled water embedded in the tag antenna substrate. The novel sensor tag is designed to provide wireless temperature readings comparable to a commercial thermocouple thermometer even in environments with high levels of interference, such as reflections. The structure of the novel sensor tag is aimed to increase its usability by minimizing user-created errors and to simplify the measurement procedure.

The sensor tag is based on a dual port sensing concept in which two ports are used to obtain sensor readings. By utilizing two ports instead of one, the effects of environmental interference, tag-reader antenna orientation and distance can be effectively minimized. Two alternative methods of acquiring the sensor reading from the operating characteristics of the two ports are presented and discussed.

Temperature measurements in practical scenarios show that by utilizing the dual port sensing concept, the developed tag produces temperature readings wirelessly which are comparable to readings from a commercial thermocouple thermometer.

The concept of dual port sensing was shown and two alternative methods on extracting sensor readings from the differences in the port operating characteristics were introduced and discussed. In this paper, the dual port sensing concept is utilized in creating a temperature sensor tag; however, the same concept can be utilized in a variety of passive wireless sensors based on UHF RFID technology. This enables a new approach in designing accurate, easy to use and easily integrable passive sensors. The dual port sensing concept is in its early stages of development; its accuracy could be improved by developing more advanced data post-processing techniques.

The accuracy of a passive dual port UHF RFID-enabled temperature sensor tag is proven to be sufficient in many applications. This indicates that other sensor types utilizing the dual port sensing concept can reach high levels of accuracy as well. Furthermore, the passive RFID-enabled sensors based on the dual port sensing concept are superior in usability versus sensor tags equipped only with a single port. Therefore, dual port sensing concept in passive UHF RFID-enabled sensor tags could make such sensors more attractive commercially and lead to truly widespread ubiquitous sensing and computing.

This paper presents a novel passive, wireless temperature sensor tag for UHF RFID systems. The sensor tag utilizes a new structure which allows tight integration of two ports and two tag antennas. The accuracy of the developed tag is confirmed throughout measurements and it is found comparable to the accuracy of commercial thermometers in practical measurement scenarios. Moreover, the paper presents a dual port sensing concept and two readout methods based on the concept which are aimed to increase the accuracy and usability of all kinds of UHF RFID-enabled sensor tags.

This paper aims to present a single-block memory-based FFT processor design with a conflict-free addressing scheme for field-programmable gate arrays FPGAs with dual-port block memories. This study aims for a single-block dual-port memory-based N-point radix-2 FFT design that uses memory locations and spending minimum clock cycle.

A new memory-based Fast Fourier Transform (FFT) design that uses a dual-port memory block is proposed. Dual-port memory allows the design to perform two memory reads and writes in a single clock cycle. This approach achieves low operational clock and smallest memory simultaneously, excluding some small overhead for exceptional address changes. The methodology is to read from while writing to a memory location, eliminating the need for excess memory and additional clock cycles.

With the minimum memory size and the simplest architecture, radix-2 FFT and single-memory block are used. The number of clock pulses spent for all FFT operations does not provide much advantage for low-point FFT operations but is important for high-point FFT operations. With the developed algorithm, N memory is used, and the number of clock pulses spent for all FFT stages is (N/2 +1)log2N for all FFT operations.

This is an original paper, which has simultaneously in whole or in part been submitted anywhere else.

This study aims to understand the factors and problems that relate to Indonesian port competitiveness and the problems that need to be addressed by major actors such as the government and port corporations.

It combines quantitative analysis from 59 survey respondents and qualitative analysis from focus-group discussions and in-depth interviews with port experts, financial bodies, port corporations and government officials on the condition of Indonesian port planning, development and financing.

An Indonesian port competitiveness model was developed, comprising government support, business support and operational performance. The authors found a gap between policy expectation and realization of port facilitation, caused by inefficient government bureaucracy, customs clearance and strategic decision-making. The government's consistency and commitment need work to encourage investor interest. Road connectivity, intermodal transportation, and energy infrastructure should be enhanced to increase operational performance. These problems are caused by a lack of feasibility analysis, consideration of local economic developments, and late adoption of standard technology. The maritime-sector workforce should be trained to be more professional with foreign players, more innovative and more open towards foreign assistance.

Port competitiveness includes government-related variables. The government’s initiatives are welcomed but are not enough. Adequate attention to both micro and macro port is necessary to increase port competitiveness. Future research should develop more comprehensive solutions to increase port competitiveness in Indonesia using problems and factors outlined here.

The study investigated the unique factors and problems that relate to Indonesian port competitiveness. It uses a national scope and rich expert data involved in Indonesia's port industry.

This paper describes the development of a fault‐tolerant database processor (DBP) system to replace OCLC's conventional file system, which not only improves overall system reliability and database availability, but also facilitates the operation and management of a large and rapidly growing online database. This database processor became operational on 16 October 1978, an achievement that represents a significant advance in the operation of information storage and retrieval systems.

This study aims to present dual band reconfigurable MIMO antenna for 5G (sub-6 GHz) and WLAN applications.

To achieve optimum bandwidth, radiation pattern and radiation efficiency, the defected ground structure (DGS) and a rectangular stub connected with the DGS are used. To further cover the sub-6 GHz spectrum (3.4–3.6 GHz) for future 5G communications, a two-element multi-input multi-output (MIMO) antenna configuration is designed by using the single element antenna. The proposed reconfigurable MIMO antenna using a PIN diode is designed on an FR4 substrate with a dielectric constant of 4.4 and a loss tangent of 0.02 and a 35 × 20 × 1.6 mm³ dimension.

The proposed antenna achieved dual operating bands of 3.4–4.1 GHz (5 G sub-6GHz applications) and 4.99–5.16 GHz (WLAN application) in the D = ON state. For D = OFF state, the proposed antenna achieved 3.55–3.65 GHz and 3.66–4.05 GHz frequency bands for 5G (sub-6GHz) applications. In terms of the envelop correlation coefficient, diversity gain, mean effective gain, total active reflection coefficient and isolation between the ports, the proposed antenna’s diversity performance characteristics are investigated and the obtained values are 0.05, 9.9 dB, ±3dB, −4dB, −15dB, respectively.

The fabricated prototype antenna on FR4 substrate has measurable parameters that are in good agreement with the simulated findings. Due to hardware design limitations, there is a minor difference between software and hardware results.

The proposed MIMO antenna is compact and reconfigurable for 5G (sub-6GHz) and WLAN applications, and from the graph, the measurements and simulations have been found to be in close agreement.

The purpose of this paper is to present the design of a compact microstrip bandpass filter (BPF) in dual-mode configuration loaded with cross-loop and square ring slots on a square patch resonator for C-band applications.

In the proposed design, the dual-mode response for the filter is realized with two transmission zeros (TZs) by the insertion of a perturbation element at the diagonal corner of the square patch resonator with orthogonal feed lines. Such TZs at the edges of the passband result in better selectivity for the proposed BPF. Moreover, the cross-loop and square ring slots are etched on a square patch resonator to obtain a miniaturized BPF.

The proposed dual-mode microstrip filter fabricated in RT/duroid 6010 substrate using PCB technology has a measured minimum insertion loss of 1.8 dB and return loss better than 24.5 dB with a fractional bandwidth (FBW) of 6.9%. A compact size of 7.35 × 7.35 mm² is achieved for the slotted patch resonator-based dual-mode BPF at the center frequency of 4.76 GHz. As compared with the conventional square patch resonator, a size reduction of 61% is achieved with the proposed slotted design. The feasibility of the filter design is confirmed by the good agreement between the measured and simulated responses. The performance of the proposed filter structure is compared with other dual-mode filter works.

In the proposed work, a compact dual-mode BPF is reported with slotted structures. The conventional square patch resonator is deployed with cross-loop and square ring slots to design a dual-mode filter with a square perturbation element at its diagonal corner. The proposed filter exhibits compact size and favorable performance compared to other dual-mode filter works reported in literature. The aforementioned design of the dual-mode BPF at 4.76 GHz is suitable for applications in the lower part of the C-band.

The purpose of this paper is to provide a miniaturized antenna design for a mobile phone. The second design is 2 × 4 elements multiple-input multiple-output (MIMO) antenna with 8 port having a substrate size is 20 × 40 mm² which fits easier within smartphone handset devices for fifth generation technology.

In this work, the first design is a conventional patch antenna, and its dual-band characteristics are obtained by characteristic mode analysis. In this method, orthogonal modes are carried out for 28 GHz and 38 GHz, and further, both orthogonal modes are excited by finite integration technique full-wave method with 50 Ohm single port coaxial feed line.

In this configuration, better return loss, high gain, larger bandwidths and low envelope correlation coefficient (ECC) are evaluated by the full-wave simulation computer simulation technology (CST) studio suite.

In this arrangement, the performance metrics of the antenna are analyzed using electromagnetic simulator CST Studio suite.

This paper aims to propose Hidden Converter (H-Converter) combined with dual port 3Ø inverter for energy storage application to produce wide range of voltage. Some of the application required wide range of voltages, but problem from E-chopper is either boost or buck mode of operations, both modes are not possible. To overcome this drawback, H-Converter is combined with dual port 3Ø inverter controlled by carrier-based pulse width modulation (CB-PWM) technique is added with zero sequence injection.

Hidden converter is a bidirectional DC-DC chopper used to convert fixed DC to variable DC and vice versa in both buck and boost modes of operations. Dual port inverter is combined with hidden DC-DC converter can produce wide range of voltages.

The bidirectional DC-AC converter requires less power for processing and consumes less power losses by using modest carrier built- pulse width modulation scheme through proposed zero structure addition.

By using this proposed strategy H-Converter can produce wide range of voltage in both the sides and mostly power is processed in the 3Ø inverter with a one stage conversion with less power loss. As a result, with one stage power conversion has more efficiency because of less power loss. This proposed converter has designed by analysis, and the real time result is tested in an experiment.

This paper aims to propose a single element, dual feed, polarisation diversity antenna. The proposed antenna operates from 2.9 to 10.6 GHz for covering the entire ultra-wideband (UWB) frequency range. The antenna is designed for usage in massive multiple input multiple output (MIMO) and closed packaging applications.

The size of the antenna is 24 × 24 × 1.6 mm³. The radiating element of the antenna is derived from the Sierpinski–Knopp (SK) fractal geometry for miniaturization of the antenna size. The antenna has a single reflecting stub placed between the two orthogonal feeds, to improve isolation.

The proposed antenna system exhibits S₁₁ < −10 dB, S₂₁ < −15 dB and stable radiation characteristics in the entire operating region. It also offers an envelope correlation coefficient < 0.01, a diversity gain > 9.9 dB and a capacity loss < 0.4 bps/Hz. The simulated and measured outputs were compared and results were found to be in similarity.

The proposed UWB-MIMO antenna has significant size reduction through usage of SK fractal geometry for radiating element. The antenna uses a single radiating element with dual feed. The stub is between the antenna elements which provide a compact and miniaturized MIMO solution for high density packaging applications. The UWB-MIMO antenna provides an isolation better than −20 dB in the entire UWB operating band.