Passive Ultra High Frequency RFID sensor with reference tag for crack detection of aluminum alloy structure

It can be ensured safe and reliable operation of a metallic structure by monitoring the positions which are easy to crack. Because the channel changes with the environment, a tag sensor in the ultra high frequency (UHF) is vulnerable to interference. This paper aims to investigate the reliability of passive RFID sensor systems with a reference tag for crack detection of aluminum alloy structures when the condition of reading distance and surrounding environment changes. The impedance and gain of tags are simulated, which provides theoretical basis for experimental analysis. With an increase of crack depth, the impedance of the sensor tag shifts to the low frequency direction, and the reference tag changes slightly. When dual tags are placed orthogonally, the gain of the sensor tag changes greatly, which means that it is more sensitive to crack depth. The backscatter power of the sensor tag shows a decline trend, and the power of the reference tag remains unchanged. The sensor features a linear response with the variation of crack depth. The sensitivity of crack characterization is better when dual tags are placed orthogonally.

Optimization of RFID reading performance based on YOLOv3 and elman neural network

As a non-contact automatic identification technology, Radio Frequency Identification (RFID) is of great significance to improve the simultaneous identification of multi-target. This paper designs a more efficient and accurate multi-tag reading performance measurement system based on the fusion of YOLOv3 and Elman neural network. In the machine vision subsystem, multi-tag images are collected by dual CCD and detected by neural network algorithm. The reading distance of 3D distributed multi-tag is measured by laser ranging to evaluate the reading performance of RFID system. Firstly, the multi-tag are detected by YOLOv3, which realizes the measurement of 3D coordinates, improves the prediction accuracy, enhances the recognition ability of small targets, and improves the accuracy of 3D coordinate detection. Secondly, the relationship between the 3D coordinates and the corresponding reading distance of RFID multi-tag are modelled by Elman recurrent neural network. Finally, the reading performance of RFID multi-tag is optimized. Compared with the state-of-the-arts, the multi-tag detection rate of YOLOv3 is 17.4% higher and the time is 3.27 times higher than that of the previous template matching algorithm. In terms of reading performance, the MAPE of Elman neural network is 1.46 %, which is at least 21.43 % higher than other methods. In running time, Elman only needs 1.69s, which is at least 28.40% higher than others. Thus, the system not only improves the accuracy, but also improves the speed, which provides a new insight for the measurement and optimization of RFID performance.

High-addition segmented refractive bifocal intraocular lens in inactive age-related macular degeneration: A multicenter pilot study

This multicenter, open-label study aimed to determine the safety and functional outcome of a high-addition segmented refractive bifocal intraocular lens (IOL) in late inactive age-related macular degeneration (AMD). Twenty eyes of 20 patients were enrolled and followed until 12 months after the intervention. Patients underwent cataract surgery with implantation of a LS-313 MF80 segmented refractive bifocal intraocular lens with a near addition of +8.0 D (Teleon Surgical Vertriebs GmbH, Berlin, Germany). The main outcome measures were distance corrected near visual acuity (DCNVA) and safety as determined by intra- and post-operative complications. Secondary outcomes included distance corrected visual acuity (CDVA), uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), the need for magnification to read newspaper, preferred reading distance, speed and performance (logRAD), as well as patient satisfaction. Mean DCNVA improved from 0.95 (±0.19) to 0.74 (±0.35) logMAR, until 6 months after surgery, P<0.05. CDVA improved from 0.70 (±0.23) to 0.59 (±0.30) logMAR, UDVA from 0.94 (±0.25) to 0.69 (±0.34) logMAR, UNVA from 1.08 (±0.19) to 0.87 (±0.43) logMAR. The mean need for magnification decreased from 2.9- to 2.3-fold, preferred reading distance from 23 to 20 cm. No intraoperative complications occurred during any of the surgeries. One patient lost > 2 lines of CDVA between 6 and 12 months, in another case, the study IOL was exchanged for a monofocal one due to dysphotopsia and decreased CDVA. Implantation of a segmented refractive bifocal IOL with +8.0 D addition improves near and distance vision in patients with late AMD and has a satisfactory safety profile.

Functional Outcomes and Reading Speeds following PRESBYOND LBV Using Nonlinear Aspheric Ablation Profiles Combined with Micro-Monovision

Purpose. To report the functional outcomes and reading speeds following PRESBYOND laser blended vision (LBV) using nonlinear aspheric ablation profiles with micro-monovision with the Carl Zeiss Meditec MEL 90 platform. Methods. Data have been collected retrospectively for all patients who underwent PRESBYOND LBV using the MEL 90 excimer laser. Postoperative binocular uncorrected distance and near visual acuity, stereo-acuity, contrast sensitivity, and reading performance were compared with pre-op values measured with patient’s progressive glasses. Mean follow-up was 6 ± 1.2 months. Results. Sixty eyes of 30 patients (mean age 50.47 ± 6.43 years) were included. Of these, 18 patients were hyperopic and 12 patients were myopic with mean SE of 1.28 ± 1.38 D and −2.84 ± 1.86 D, respectively. At 6 months, the mean binocular UDVA was ≥−0.03 ± 0.06 log MAR and the mean binocular UNVA was ≥0.22 ± 0.04 log MAR. The uncorrected reading speeds (words per minute) at the preferred reading distance of 46.17 cm, 60 cm, and 80 cm were significantly better ( p value <0.01), whereas the smallest letter size and reading acuities were comparable to the preoperative values ( p > 0.05 for all distances). Uncorrected contrast sensitivity log values showed mild reduction; however, this was not statistically significant for any spatial frequency. There was a significant reduction in post uncorrected stereopsis to 89.67 arc sec, compared with pre-op corrected stereopsis (50.67 arc sec); however, it recovered fully with near correction (53.33 arc sec, p > 0.05 compared with pre). Conclusion. PRESBYOND LBV resulted in significantly better reading speeds and satisfactory functional visual outcomes, without a permanent change in stereo-acuity and contrast sensitivity 6 months postoperatively.

Assessment of Outdoor Lighting: Methods for Capturing the Pedestrian Experience in the Field

This study assessed whether methods for capturing the pedestrian experience of outdoor lighting, previously evaluated in a full-scale laboratory, were applicable in a real-world setting. It applied an approach capturing the human response to outdoor lighting in a systematic way, by assessing perception, evaluation and behaviour in the lit environment. The study involved 81 participants from two age groups (Young—n: 48, mean age: 26, 63% women; Elderly—n: 33, mean age: 69, 67% women) and was carried out on a pedestrian path in a park in the centre of Malmö, Sweden, in the evenings during wintertime. Two LED lighting applications, differing in light distribution, uniformity and horizontal illuminance, were presented, and the pedestrians’ perception (facial expression recognition and sign reading), evaluation (arousal, valence and perceived outdoor lighting quality) and behaviour (pedestrian flow) were assessed. The results from the perceptual tasks differed significantly between the lighting applications, in favour of the lighting application with greatest uniformity and horizontal illuminance. There was a significant difference in sign reading distance between the two age groups. The methods applied in this study are feasible to administer and could be used to assess lighting solutions in order to capture the needs of vulnerable groups.

Efficient Directional Antenna Design Suitable for Ubiquitous Power Internet of Things

Today’s power systems are developing from traditional multi-sensor systems to ubiquitous power Internet of Things systems. The environmental backscatter technology makes communication equipment get rid of the dependence on power supply, is more energy-efficient, and effectively extends the communication distance, which is very suitable for power Internet of Things scenarios. Tag antenna is an important part of environmental backscattering, but it has problems such as low reliability and insufficient reading distance in the traditional power Internet of Things. In view of the above problems, this paper designs a double-antenna structure tag antenna, which adopts omnidirectional receiving and directional transmitting methods to achieve the purpose of comprehensive signal coverage for the power Internet of Things application scenarios. It has the characteristics of obvious gain, small side lobe, and strong anti-interference.

Clinical Study on the Influence of Eye Care Habits on Myopia in School-age Children

In order to explore the relationship between the habit of using eyes and myopia, summarize and put forward to develop good habit of using eyes of school-age children to achieve the purpose of preventing myopia. 960 school-age children aged 7 to 12 were selected from the ophthalmology clinic of Fujian Provincial Government Hospital. The data collected included reading distance, sleep time, average daily outdoor activity time, average daily continuous eye use time. Ophthalmologists are responsible for visual examination, which includes mild myopia, moderate myopia and severe myopia. SPSS 22.0 statistical software was used for data processing. As a results, P < 0.05 was statistically significant. There are significant differences in the distribution of sleep time among the three groups (P < 0.05); There are significant differences in the time distribution of each continuous close eye use among the three groups (P < 0.05); There are significant differences in the distribution of distance habit among the three groups (P < 0.05); There are significant differences in the distribution of outdoor activity time among the three groups (P < 0.05).Myopia is closely related to the time of close eye use, the distance of eye use, the length of sleep and the length of outdoor activities.

Piracy Anticipation System Design on Ships

One of the factors that caused the hijacking of ships was the lack of a security system in sailing. The purpose of this study is to design a piracy anticipation system on a ship to provide early warning to ship officers and design a shooting system, determine the distance to objects detected by sensors and design a system of sending information to the BAKAMLA (Sea Safety Agency) team in case of piracy. This research device uses four ultrasonic sensors to detect and determine the distance to objects that enter the ship’s area. The sensor reading distance is 2 cm to 50 cm. The ship’s area monitoring system uses a camera and a Raspberry Pi to improve the surveillance of ship personnel in monitoring the situation around the ship. The system installed on this ship displays video streaming and detects objects using ultrasonic sensors to determine the distance of the detected object and capture it. Video streaming, distance, and photos of detected objects can be seen on the website by opening a particular site for this monitoring system. The website is equipped with admin_name and passwords and photos of objects can be downloaded on the website. This device is equipped with a buzzer to provide early warning to the ship officers. When an object is detected. The active buzzer and SIM used will send information about piracy to the BAKAMLA team.

Automation system spraying desinfectant at Universitas Musamus

During the pandemic the learning process was conducted online and partly done face-to-face so that every day there are still students and employees who are in the campus environment. One of the prevention of covid transmission is done by spraying disinfectant when passing through the front gate of the campus. A design a prototype of an automatic disinfectant spray system and build a system on the prototype that can provide real time information related to monitoring the contents of the disinfectant tank by designing hardware. The results of the research built a disinfectant spraying automation system in front of the entrance gate of Universitas Musamus, to get results that prove that the system performance has been running as expected, there are several tests carried out such as tool testing and measuring the reading distance of the ultrasonic proximity sensor, and testing. sending SMS alert. How to provide information that the liquid in the tank has run out. Sensor sends a status signal for the disinfectant liquid level after spraying, a warning SMS is sent went the distance of disinfectant liquid and the ultrasonic sensor at a predetermined threshold.

Rancang Bangun Pengaman Sepeda Motor Menggunakan RFID Berbasis Arduino

The safety of a motorcycle is very important for vehicle owners. Until now, most motorbikes still rely only on the key to contact the vehicle itself. In the case of vehicle theft, it is very easy for the perpetrator of the theft to use the letter "T" key. Therefore an additional vehicle safety is required which is difficult to break apart from the ignition key. The purpose of this research is to design and implement motorcycle safety using Arduino-based Radio Frequency Identification (RFID) as additional vehicle safety. The author uses an RFID card / tag to add security to the vehicle starting system with a card / tag reading distance that can be read by an RFID reader. The ID code on the RFID Card must be inputted into the Arduino so that the RFID reader can read the ID Card that has been inputted into the Arduino. Based on the results of the tests that have been done, it is found that the reading distance of the RFID Card / Tag ranges from 1 cm to 3.5 cm. If the correct ID code is inputted, the electrical system is active and vice versa if the ID code entered is wrong, the buzzer will sound and the electrical system in the vehicle is not active / does not turn