A proposed resistance-to-time converter with switching impulse calibrators for resistive bridge sensors

This paper presents a simple resistance-to-time converter. It consists of two voltage comparators, a ramp voltage generator, two logic gates and impulse voltage calibrators. A square-wave generator circuit is suggested in this paper. The design is simple and independent of the OPAMP offset issues. The resulting square-wave is rectified to get its DC equivalent and to a triangular output; the two outputs are applied to a comparator for generating a digital output with duty cycle proportional to a change in resistance upon which is dependent the DC

2 point block backward difference method for solving Riccati type differential problems

A two point block backward difference method is established to solve Riccati differential equations directly. Based on a predictor-corrector two point block backward difference method (2PBBD), a code is developed using a set of integration coefficients that eliminates the need to be calculated at every step change. The method requires calculating the integration coefficients only once in the beginning. The 2PBBD has an added advantage of a recurrence relationship between coefficients of different orders which provides a more elegant algorithm. The recurrence relationship between coefficients also reduces the computational cost

mmWave Four-Element MIMO Antenna for Future 5G Systems

This paper presents an S-shape four-port Multiple Input Multiple Output (MIMO) wideband mmWave antenna with bandwidth of 25 GHz to 39 GHz. The antenna is designed on 0.254 mm ultra-thin RO5880 with permittivity of 2.3. The dimensions of proposed S-shape antenna are 10 12 mm for single element and 24 24 mm for four-port MIMO configuration. A decoupling network is introduced to further compress mutual coupling among MIMO elements. The peak gain achieved is 7.1 dBi and MIMO assembly delivers diversity scheme. The proposed MIMO antenna is fabricated, and simulated results are found to be in excellent agreement with simulations. Through the results obtained, the proposed MIMO antenna system can be considered as a potential candidate for future mmWave devices.This project has received funding from Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant 801538

mmWave four-element mimo antenna for future 5G systems

This paper presents an S-shape four-port Multiple Input Multiple Output (MIMO) wide-band mmWave antenna with bandwidth of 25 GHz to 39 GHz. The antenna is designed on 0.254 mm ultra-thin RO5880 with permittivity of 2.3. The dimensions of proposed S-shape antenna are 10 × 12 mm for single element and 24 × 24 mm for four-port MIMO configuration. A decoupling network is introduced to further compress mutual coupling among MIMO elements. The peak gain achieved is 7.1 dBi and MIMO assembly delivers diversity scheme. The proposed MIMO antenna is fabricated, and simulated results are found to be in excellent agreement with simulations. Through the results obtained, the proposed MIMO antenna system can be considered as a potential candidate for future mmWave devices

WATER QUALITY ASSESSMENT AND THE PREVALENCE OF ANTIBIOTICRESISTANT BACTERIA FROM A RECREATIONAL RIVER IN KUCHING, SARAWAK, MALAYSIA

Recreational activities may affect a river’s water quality, which may pose health risks to those in direct contact with the water. This study aims to analyse the water quality if Jangoi River in Kuching, Sarawak, by measuring the conventional chemical and biological parameters and to characterise the bacteria isolated from the water based on their antibiotic susceptibility. The determination of the water quality is based on the Department of Environment’s Malaysian Water Quality Index (WQI), which was carried out at three sampling stations (upstream, middle stream and downstream) in two different sampling trips. Six water quality parameters were measured: Dissolved oxygen, biological oxygen demand, pH, chemical oxygen demand (COD), ammoniacal nitrogen and total suspended solid. The WQI values of the river ranged from 88% to 92%, classifying the river under Class I. The one-way ANOVA analysis revealed that the parameter values for all the three stations are not significantly different, except for the COD. The higher COD value of the upstream water could be due to the release of wastewater from houses and agricultural activities near Jangoi River. The faecal coliform and total coliform counts ranged from 650 CFU/100 mL to 1,000 CFU/100 mL and 20,050 CFU/100 mL to 23,250 CFU/100 mL, respectively.Nine bacteria were isolated and 16S rRNA PCR and DNA sequencing. The DNA sequencing revealed the presence of Escherichia coli, Chromobactium violaceum, Lelliota amnigena,Pseudomonas aeruginosa, Achromobacter xylosoxidans, Stenotrophomonas maltophilia, Pseudomonas hibiscicola, Achromobacter mucicolens and Bacillus pacificus. Antibiotic susceptibility tests demonstrated the highest percentage of susceptibility for ciprofloxacin (100%), followed by ampicillin (40%) and chloramphenicol (40%). However, the highest percentage of resistance (60%) was shown by erythromycin. The multiple antibiotic resistant (MAR) index in this study ranged from 0.0 to 0.6. The river’s WQI categorisation and microbiological status are inconsistent, indicating the need to modify the WQI formula to include the microbial parameter. Additionally, this study recommends the establishment of water quality and antibiotic resistance pattern monitoring programmes to anticipate the emergence of MAR bacteria in the aquatic environment and to document the continuous water quality state of Sarawak’s recreational rivers

A high linearity CMOS RF amplifier for power control module in RFID reader

Radio frequency identification (RFID) is the latest technology for automatic identification, which allows the transmission of a unique serial number wirelessly. Power control module of RFID reader is used to perform digital signal processing techniques and procedures over the received data from the RFID readers. A high linearity CMOS RF (radio frequency) power amplifier has the advantage of being low-cost and easily integrated on chip. It has become the smart technology of choice for wireless devices (RFID readers). This work demonstrates a 3.3V single voltage self-biased 2.4GHz– 2.5GHz high linearity RF power amplifier for RFID applications. The proposed amplifier achieved 81.1 dB gain, output power at P1dB -4.0 dBm, 1-dB gain compression power with 10.0% power efficiency (PE) and 17.4% power-added efficiency (PAE). Furthermore, high linearity with 1.6dBc for IM3, -6.633dBm and -2.887dBm third-order intercept point IIP3 and OIP3 at frequency of 2.45GHz is also measured. The Adjacent Channel Power Ratio (ACPR) has been achieved -7.26dBc for input port and -1.0dBc for output port. The amplifier also exhibited very good isolation of 2.85dB, the insertion loss of 0.8dB and return loss of 9.94dB. Simulations were conducted using Mentor Graphic software tools

Severe pulmonary tuberculosis with organizing pneumonia: a diagnostic ambiguity

Pulmonary TB may present insidiously and ambiguously, leaving clinicians with a diagnostic dilemma. A 30-year-old lady with underlying spinocerebellar ataxia presented with progressive shortness of breath, prolonged cough with whitish sputum, loss of appetite and weight loss of 1-year duration. Physical examination showed a cachectic, tachypnoeic female with finger clubbing and coarse crepitations on lung auscultation. Chest radiograph showed bilateral air space opacities relatively sparing the upper zone. Contrast-enhanced CT thorax revealed bilateral cavitary necrotising consolidations, multiple scattered lung nodules with surrounding ground-glass opacities. After exclusion of alternative diagnoses, cryptogenic organizing pneumonia diagnosis was made. She had a rapid clinic improvement once steroid was started. TB polymerase chain reaction (PCR) from bronchoscopic bronchial washing eventually was positive. Anti-TB treatment was started, and oral steroid was slowly tapered down. Organizing pneumonia (OP) may complicate pulmonary TB. Diagnosing OP without lung biopsy requires a multi-disciplinary approach, taking into consideration all available evidences. Early steroid therapy is lifesaving and should be considered after thorough exclusion of alternative diseases

A proposed resistance-to-time converter with switching impulse calibrators for application in resistive bridge sensors

This paper presents a simple resistance-to-time converter. It consists of two voltage comparators, a ramp voltage generator, two logic gates and impulse voltage calibrators. A square-wave generator circuit is suggested in this paper. The design is simple and independent of the OPAMP offset issues. The resulting square-wave is rectified to get its DC equivalent and to a triangular output; the two outputs are applied to a comparator for generating a digital output with a duty cycle proportional to a change in resistance upon which is dependent the DC

Development of photo forensics algorithm by detecting photoshop manipulation using error level analysis

Nowadays, image manipulation is common due to the availability of image processing software, such as Adobe Photoshop or GIMP. The original image captured by digital camera or smartphone normally is saved in the JPEG format due to its popularity. JPEG algorithm works on image grids, compressed independently, having size of 8x8 pixels. For unmodified image, all 8x8 grids should have a similar error level. For resaving operation, each block should degrade at approximately the same rate due to the introduction of similar amount of errors across the entire image. For modified image, the altered blocks should have higher error potential compred to the remaining part of the image. The objective of this paper is to develop a photo forensics algorithm which can detect any photo manipulation. The error level analysis (ELA) was further enhanced using vertical and horizontal histograms of ELA image to pinpoint the exact location of modification. Results showed that our proposed algorithm could identify successfully the modified image as well as showing the exact location of modifications

A Review of Entomopathogenic Nematodes as a Biological Control Agent for Red Palm Weevil, Rhynchophorus ferrugineus (Coleoptera: Curculionidae)

Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae) is a severe pest of palm trees worldwide. The development and feeding activities of R. ferrugineus larvae inside the trunk damage palm trees. However, the absence of noticeable infestation signs at an early stage contributes to the spread of the attack. Integrated pest management (IPM) has been introduced to control R. ferrugineus infestation by implementing various approaches and techniques. The application of chemical pesticides has shown impressive results. However, biological control should be applied as an alternative solution due to adverse environmental impacts and pest resistance issues. One example is the use of entomopathogenic nematodes (EPNs) as biological control agents, which can forage and attack targeted pests without compromising the environment and other nontarget organisms. EPNs and their symbiotic bacteria have a mutualistic interaction that can kill the host within a short period of time. Therefore, this review emphasizes the effectiveness of entomopathogenic nematodes and their symbiotic bacteria against R. ferrugineus