Journal articles: 'Tractors – Transmission devices – Evaluation'

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Majdan, R., Z. Tkáč, B. Stančík, R. Abrahám, I. Štulajter, P. Ševčík, and M. Rášo. "Elimination of ecological fluids contamination in agricultural tractors." Research in Agricultural Engineering 60, Special Issue (December 30, 2014): S9—S15. http://dx.doi.org/10.17221/27/2013-rae.

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This contribution presents the elimination of pollution for ecological fluids of UTTO (universal tractor transmission oils) type in agricultural tractors. The common oil filling of the transmission and hydraulic system is polluted by residues of old fillings from attachments such as ploughs, trailers, etc. In the tractor Zetor Forterra 114 41, a newly developed synthetic ecological fluid HEPR (VDMA 24568) was applied. The oil showed pollution limits after completing 900 engine hours. For this reason, a filtration device was designed to clean mainly biodegradable fluids UTTO. On the basis of fluid application evaluation and performed filtration, it can be concluded that a simple and affordable filtration system reduces the concentration of the most dangerous contamination particles (particles lager than 14 μm) by up to 30%.

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Tkáč, Z., R. Majdan, Š. Drabant, J. Jablonický, R. Abrahám, and P. Cvíčela. "The accelerated laboratory test of biodegradable fluid type “ertto”." Research in Agricultural Engineering 56, No. 1 (March 13, 2010): 18–25. http://dx.doi.org/10.17221/26/2009-rae.

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The accelerated laboratory tests can evaluate the properties of new biodegradable fluids under relatively short time. These test results are the ground for the continuity of the tests under operation conditions in machine. The paper presents the test of new biodegradable hydraulic fluid type “Environmentally responsible tractor transmission oil” by designed special test device. The test evaluation was realized by technical state of concrete hydrostatic pump UD 25 which is used in tractors Zetor Forterra. This pump was loaded by cyclic pressure loading during the test with tested fluid. The evaluated parameter was flow efficiency of hydrostatic pump which reached the value 7.3% after the test. The reached value hints a high quality of the tested fluid (the limit value per standard is the flow efficiency decrease – 20%).

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Majdan, R., J. Kosiba, J. Tulík, D. Kročková, and V. Šinský. "The comparison of biodegradable hydraulic fluid with mineral oil on the basis of selected parameters ." Research in Agricultural Engineering 57, Special Issue (December 6, 2011): S43—S49. http://dx.doi.org/10.17221/7/2011-rae.

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The paper presents a comparison of two fluids quality. The first one was mineral oil type UTTO which is commonly used in the transmission and hydraulic systems of agricultural tractors. The second one tested was biodegradable hydraulic fluid type ERTTO which could replace the toxic mineral oil. Both fluids were tested under the same test conditions using a special test device. The selected parameters of the hydrostatic pump were evaluated. The tests were evaluated according to the parameters describing the technical state of the hydrostatic pump as follows: flow efficiency, decrease of flow efficiency and cleanliness level of the fluid tested. This additional measurement verifies the test results. On the basis of the results achieved, we can state that the biodegradable hydraulic fluid exerts no harmful influence on the technical state of the hydrostatic pump. Therefore, the biodegradable fluid tested can be applied to the agricultural tractor. Has been demonstrated that the selected parameters are suitable for the evaluation of hydraulic fluid during its working performance. Therefore, these parameters will be used in the next examination of the fluid under operational conditions of an agricultural tractor.

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Wang, Bingchen, Sigeru Omatu, and Toshiro Abe. "Quality Evaluation of Transmission Devices Using the GA." IEEJ Transactions on Electronics, Information and Systems 123, no. 10 (2003): 1776–82. http://dx.doi.org/10.1541/ieejeiss.123.1776.

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Pochi, Daniele, Roberto Fanigliulo, Carlo Bisaglia, Maurizio Cutini, Renato Grilli, Monica Betto, and Laura Fornaciari. "Vegetable-based Oil as UTTO Fluid for Agricultural Tractors Application." Applied Engineering in Agriculture 36, no. 1 (2020): 79–88. http://dx.doi.org/10.13031/aea.13488.

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HighlightsLubricants are commonly used in agricultural activities involving machines.To reduce lubricants impact on the environment, a process has been started for replacing them with products obtained from vegetable oils.Tests have been carried out to explore the possibility of introducing vegetable-based UTTO in tractors.Results encourage to deepen the behavior of vegetable-based oils and develop specific test bench and methods.Abstract. To reduce the impact of mineral and synthesis lubricants on the environment, a process has been started for replacing them with lubricants and hydraulic fluids obtained from high-oleic vegetable oils, with good tribological properties, high biodegradability, and low toxicity. Test have been carried out at Research Center for Engineering and Agro-Food Processing of Monterotondo, Rome, Italy, with the aim of comparing the performances provided by a standard agricultural tractor supplied with conventional Universal Tractor Transmission Oil (UTTO) fluid and with a vegetable-based oil in their transmission-hydraulic system group. The research aimed at assessing differences, if any, in tractor’s performances attributable to the fluids in comparison. For a better comparison, the tests were carried out under controlled conditions, connecting the tractor, at first to a dynamometric brake used in engine and transmission tests, then to a test rig for hydraulic lifts. The results, although non generalizable, were encouraging, indicating that the tractor’s performances with the two fluids, after 30 h work cycles, were similar both for transmission and hydraulic lift. On the other hand, the reduction observed in the viscosity of the biofluid requires the deepening of the aspects related to its durability. The results also allowed to focus some basic aspects of the evaluation of biofluids and to identify some methodological approaches mainly based on the comparation of fluids performance during repeatable work cycles and on the assessment of how their physical properties evolve overtime. Keywords: Biolubricant, Engine performance, High-oleic sunflower oil, Hydraulic lift, Lifting force, Power transmission.

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Rufo, J., J. Rabadan, F. Delgado, C. Quintana, and R. Perez-Jimenez. "Experimental evaluation of video transmission through LED illumination devices." IEEE Transactions on Consumer Electronics 56, no. 3 (August 2010): 1411–16. http://dx.doi.org/10.1109/tce.2010.5606277.

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Máchal, Pavel, Radoslav Majdan, Zdenko Tkáč, Bohuslav Stančík, Rudolf Abrahám, Ivan Štulajter, Peter Ševčík, and Milan Rášo. "Design and verification of additional filtration for the application of ecological transmission and hydraulic fluids in tractorc." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 61, no. 5 (2013): 1305–11. http://dx.doi.org/10.11118/actaun201361051305.

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This contribution presents the design and function verification of additional filtration. It is intended for the common transmission and hydraulic oil filling of tractors. The main role of this filtration concept is to ensure a high level of oil cleanness as a condition for the application of ecologic fluids in tractors. The next one is to decrease the wear of lubricated tractor components, the degradation of oil and eventually to extend the interval of oil change. The designed additional filtering is characterized by ease installation through the use of quick couplings and hoses to the external hydraulic circuit. Therefore, the filtration is suitable for various tractor types. Filter element has been designed with the filter ability 1micron and the ability to separate to 0.5 dm3 of water from oil. Function of additional filtration was verified during the 150 engine hours of tractor operation. During this time period the oil contamination was evaluated on the basis of chemical elements content such as Fe, Cu, Si, Al, Ni, Mo and Cr. The additive concentration was evaluated on the basis of chemical elements content such as Ca, P and Zn. During the test operation of tractor the concentration decrease of chemical elements reached the values 25.53 % (Fe), 23.53 % (Si), 25 % (Al) and 5.5 % (Cu). The decrease of additive concentration reached only medium level (6.6 %). Therefore, the designed additional filtration doesn’t remove additives from oil. Based on the evaluation of the content of chemical elements (that representing contamination and additives), we can say that the designed filtering method is suitable for use in agricultural tractors.

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Wang, Bingchen, Sigeru Omatu, and Toru Fujinaka. "Quality evaluation of transmission devices using the GA with FP." Artificial Life and Robotics 8, no. 2 (June 2004): 140–46. http://dx.doi.org/10.1007/bf02678882.

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Wang, Bingchen, Sigeru Omatu, and Toru Fujinaka. "Quality evaluation of transmission devices using the GA with FP." Artificial Life and Robotics 8, no. 2 (December 2004): 140–46. http://dx.doi.org/10.1007/s10015-004-0301-0.

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Ito, Yuki, Hiroshi Mochizuki, Hideo Nakamura, Ryo Ishikawa, Minoru Sano, and Satoshi Nishida. "Development and Evaluation of CDM-QAM Transmission Devices for Track Circuit." IEEJ Transactions on Industry Applications 135, no. 4 (2015): 444–50. http://dx.doi.org/10.1541/ieejias.135.444.

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Kim, Wan-Soo, Yeon-Soo Kim, and Yong-Joo Kim. "Development of Prediction Model for Axle Torque of Agricultural Tractors." Transactions of the ASABE 63, no. 6 (2020): 1773–86. http://dx.doi.org/10.13031/trans.14012.

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HighlightsA prediction model was developed for estimating the axle torque of an agricultural tractor.The model was developed by complementing and modifying a previously proposed traction equation.Compared to the actual axle torque, the proposed model attained MAPE of 2.1%, RMSE of 29 Nm, and RD of 2.7%.The model predicted axle torque more accurately than the traction force-based prediction model.Abstract. The tractor driving axle torque is an important factor in optimal transmission design and service life evaluation. Axle torque measurement sensor systems are very expensive, and traction force-based axle torque prediction models cannot accurately estimate the axle torque because they do not consider both the conditions of the tractor and the attached implement. Therefore, in this study, a prediction model was developed to estimate the axle torque of an agricultural tractor based on the traction force equation and motion resistance. A load measurement system was established to verify the developed prediction model, and actual field torque data were collected through field tests. The developed prediction model was verified by comparing the results of five reference prediction methods, including weight, engine-rated torque, and three traction equations (Wismer-Luth, ASABE Standard D497.4, and Brixius), using the measured axle torque. Performance evaluation was conducted based on the main variables, including travel speed, tillage depth, and slip ratio. The proposed prediction model was found to be closest to the 1:1 line at all travel speeds, tillage depths, and slip ratios, implying that it can best explain the measured torque values among all prediction models. Compared to the other prediction models, the proposed prediction model’s results under all variable conditions had an R2 of 0.65, MAPE of 2.1%, RMSE of 29 Nm, and RD of 2.7%, indicating excellent prediction of the measured torque. The results show that the developed prediction model can be applied to axle torque prediction by explaining the actual measured axle torque. Keywords: Agricultural tractor, Axle torque, Prediction model, Torque estimation, Traction force.

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Shutenko, Vladimir V., and Natalia V. Perevozchikova. "Mathematical Modeling and Evaluation of the Transport and Technological Module Drive Efficiency." Elektrotekhnologii i elektrooborudovanie v APK 67, no. 1 (March 28, 2020): 87–92. http://dx.doi.org/10.22314/2658-4859-2020-67-1-87-92.

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The main reason for using heavy tractors is the high energy saturation of modern agricultural machinery. For the full engine power realization, the tractor must have high traction performance. Ballasting, the drive wheels doubling, transport and technological modules increase traction. (Research purpose) To determine the best way to increase traction. (Materials and methods) The authors calculated the propulsors pressure of the Terrion 3180 tractor loaded with ballast weights and aggregated by the MES-300 transport and technological module on the soil using mathematical modeling. It was noted that the pressure on the soil is 38 percent less when using the transport and technological module, with the same traction. (Results and discussion) The authors analyzed the design of the MES-300. It was revealed that to improve the transport and technological module operation, it was necessary to reduce weight. It was found that when using the transport and technological module to increase the tractor traction, fuel consumption increased by an average of 3 percent. The authors showed that it was possible to reduce consumption by improving the transmission, which was based on the drive axle from the T-150K tractor. They found out that the effective drive scheme was an individual drive of the drive wheels, which allowed to combine the positive sides of the differential and hard drive. They performed mathematical modeling of a transport and technological module with various types of transmission (mechanical, hydrostatic, electric). It was stated that hydrostatic transmission was the most efficient type of transmission in terms of fuel economy. (Conclusions) The authors determined that the modernization of the MES-300 through the use of a transmission with an individual drive on each wheel had positive results: a change in power and torque supplied to each wheel; reduction in kinematic mismatch and power circulation; increase fuel efficiency.

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Azizi, P., N. Sakenian Dehkordi, and R. Farhadi. "Design, Construction and Evaluation of Potato Digger with Rotary Blade." Cercetari Agronomice in Moldova 47, no. 3 (September 1, 2014): 5–13. http://dx.doi.org/10.2478/cerce-2014-0022.

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Abstract Potato has an important role in human food. It was the sixth alimentary product in the world after sugar cane, maze, rice, wheat and milk in 2011 year. In addition, potato is the third product in Iran after wheat and sugar cane in 2011 year. Therefore, any attempt in the improvement of potato harvester will be valuable. In this study, a new semi-mounted one-row potato digger with rotary blade was designed and made in the workshop of Shahrekord University. It can be connected to rotary potato graders. Transmission system was mechanical from tractor (PTO) to blade by belt, pulley, gearbox, chain and sprocket. Blade diameter was 76 cm and the length was 10 cm which was assigned by the researchers. For separating of soil from potato, a helix containing bars with 2.6 cm distance and diameter of 9 mm was applied. Entered soil into set was calculated as 227 ton/h. Required power was got 5.5 horsepower. Computerized model of set was prepared in Mechanical Desktop Software and potato motion was studied in Visual Nastran Software. The device was tested at field with various advance speed, blade angle and rotational speed. Results showed that advance speed of 1.5-3 km/h, rotational speed of 20-25 RPM and blade angle of 10- 15° were proper for system. The average of damaged potatoes was 4%.

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Verma, Pawan Kumar, Rajesh Verma, Arun Prakash, and Rajeev Tripathi. "Throughput-Delay Evaluation of a Hybrid-MAC Protocol for M2M Communications." International Journal of Mobile Computing and Multimedia Communications 7, no. 1 (January 2016): 41–60. http://dx.doi.org/10.4018/ijmcmc.2016010104.

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This paper proposes a robust hybrid-MAC protocol for direct communication among M2M devices with gateway coordination. The proposed protocol combines the benefits of both contention-based and reservation-based MAC schemes. The authors assume that the contention and reservation portion of M2M devices is a frame structure, which is comprised of two sections: Contention Interval (CI) and Transmission Interval (TI). The CI is based on p-persistent CSMA mechanism, which allows M2M devices to compete for the transmission slots with equal priorities. After contention, only those devices, which have won time-slots, are allowed to transmit data packets during TI. In the authors' proposed MAC scheme, the TI is basically a TDMA frame and each M2M device is 802.11 enabled. Each M2M transmitter device and its corresponding one-hop distant receiver communicate using IEEE 802.11 DCF protocol within each TDMA slot to overcome the limitations of TDMA mechanism. The simulation results demonstrate the effectiveness of the proposed hybrid-MAC protocol.

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Alhaj, Abdullah A. "Performance Evaluation of Secure Data Transmission Mechanism (SDTM) for Cloud Outsourced Data and Transmission Layer Security (TLS)." International Journal of Cloud Applications and Computing 4, no. 1 (January 2014): 45–49. http://dx.doi.org/10.4018/ijcac.2014010104.

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The Cloud has become a significant topic in computing; however, the trend has established a new range of security issues that need to be addressed. In Cloud, the data and associated software are not under their control. In addition, with the growing demands for Cloud networks communication. With the increasing demand for computer communications the need for security is growing dramatically. The existing research related to security mechanisms focuses on security of the data transmission in the communication networks only. The authors developed specific Secure Data Transmission Mechanism (S SDTM) for cloud outsourced data is a set of technologies and solutions to enforce security policy and bandwidth compliance on all devices seeking to access network computing resources, in order to limit damage from emerging security threats and to allow network access only to compliant and trusted endpoint devices. IPSec is a suite of protocols that adds security to communications at the IP level. Protocols within the IPSec suite make extensive use of cryptographic algorithms. Since these algorithms are computationally sophisticated, some hardware accelerators are needed to support high throughput. In this paper, the authors compare between secure data transmission mechanism for cloud outsourced data with preemption control algorithm and TLS to improve the properties of the S SDTM and the Virtual Private Networks (VPN) built with both protocols.

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Hu, Tao, Gang Li, Yuling Zuo, and Xuedong Zhou. "Risk of Hepatitis B Virus Transmission via Dental Handpieces and Evaluation of an Antisuction Device for Prevention of Transmission." Infection Control & Hospital Epidemiology 28, no. 1 (January 2007): 80–82. http://dx.doi.org/10.1086/510808.

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We evaluated the risk of hepatitis B virus (HBV) transmission via dental handpieces and the effects of an antisuction device in preventing HBV contamination. The results of our study show that under certain conditions, HBV transmission can occur when an antisuction device is used during dental procedures. We conclude that such devices may decrease contamination, but do not eliminate it.

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Kubde, Vidya S., and Sudhir Sawarkar. "Evaluation of MPTCP Schedulers in Diverse Scenarios." European Journal of Electrical Engineering and Computer Science 5, no. 2 (April 23, 2021): 50–54. http://dx.doi.org/10.24018/ejece.2021.5.2.275.

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Multipath Transmission Control Protocol (MPTCP) is an extension of TCP meant for multihomed devices, which uses all the available interfaces for a single connection. MPTCP was evolved for Bandwidth aggregation and re silence to network failure. The wireless networks of multihomed devices are of different characteristics, when used together decreases Quality of Service (QoS). MPTCP schedulers tried to fill this gap with different approaches. In this paper we tried to study these schedulers in different network scenarios and came with the findings that to achieve good throughput and decrease download time, only fast paths are preferred.

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Kang, Jiheon, and Doo-Seop Eom. "Offloading and Transmission Strategies for IoT Edge Devices and Networks." Sensors 19, no. 4 (February 18, 2019): 835. http://dx.doi.org/10.3390/s19040835.

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We present a machine and deep learning method to offload trained deep learning model and transmit packets efficiently on resource-constrained internet of things (IoT) edge devices and networks. Recently, the types of IoT devices have become diverse and the volume of data has been increasing, such as images, voice, and time-series sensory signals generated by various devices. However, transmitting large amounts of data to a server or cloud becomes expensive owing to limited bandwidth, and leads to latency for time-sensitive operations. Therefore, we propose a novel offloading and transmission policy considering energy-efficiency, execution time, and the number of generated packets for resource-constrained IoT edge devices that run a deep learning model and a reinforcement learning method to find an optimal contention window size for effective channel access using a contention-based medium access control (MAC) protocol. A Reinforcement learning is used to improve the performance of the applied MAC protocol. Our proposed method determines the offload and transmission strategies that are better to directly send fragmented packets of raw data or to send the extracted feature vector or the final output of deep learning networks, considering the operation performance and power consumption of the resource-constrained microprocessor, as well as the power consumption of the radio transceiver and latency for transmitting the all the generated packets. In the performance evaluation, we measured the performance parameters of ARM Cortex-M4 and Cortex-M7 processors for the network simulation. The evaluation results show that our proposed adaptive channel access and learning-based offload and transmission methods outperform conventional role-based channel access schemes. They transmit packets of raw data and are effective for IoT edge devices and network protocols.

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Shashurin, V. D., N. A. Vetrova, and A. A. Filyaev. "Evaluation of channel transmission of nanoelectronic devices on low-dimensional structures with quantum confinement." Journal of Physics: Conference Series 1560 (June 2020): 012048. http://dx.doi.org/10.1088/1742-6596/1560/1/012048.

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Elias, Caio Caraciolo Rodrigues, Domingos D’Oliveira Cardoso, Marcos Paulo Cavaliere de Medeiros, Cláudio Luiz de Oliveira, Sérgio Gavazza, Samanda Cristine Arruda Correa, and Edmilson Monteiro Souza. "EVALUATION OF AMBIENT DOSE EQUIVALENT SURROUNDING TRANSMISSION FULL-BODY SCANNERS." Radiation Protection Dosimetry 189, no. 4 (May 2020): 444–51. http://dx.doi.org/10.1093/rpd/ncaa066.

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Abstract This study analyses the ambient dose equivalent around transmission full-body scanners used in Brazilian prisons and airports. In order to achieve this goal, three transmission full-body scanners of the same model assembled by a Brazilian manufacturer were evaluated. Ambient dose equivalent rates were measured at several positions around these screening devices with the help of an ionisation chamber made by Ludlum, model 9DP. These systems consist of an X-ray generator with three distinct modes of operation, each with a unique value for maximum energy (100, 150 and 160 keV) and current (0.4, 0.5 and 0.9 mA). Results show the integrated dose per scan at each of the measurement positions considered, presenting values for ambient dose equivalent with and without an individual being scanned, in order to take into account the scattering due to the presence of a human body.

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Yang, Jae Kyo, D. J. Park, J. Kim, Si Young Chang, Chung Hyo Lee, Tohru Sekino, Koichi Niihara, and Yong Ho Choa. "Preparation and Evaluation of Metal/Ceramic Nanocomposites for High Frequency Inductive Devices." Key Engineering Materials 317-318 (August 2006): 869–72. http://dx.doi.org/10.4028/www.scientific.net/kem.317-318.869.

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Fe/MgO nanocomposites, which are applicable to high frequency electronic devices, were fabricated by ultrasonic spray pyrolysis and selective reduction processes. Transmission electron micrographs showed that nano ferromagnetic Fe particles were isolated by MgO insulating matrix. With the increase of the reduction temperature, the particle size and saturation magnetization of the nanocomposites increased, which resulted in the decrease of the coercive force and the increase of the permeability. Furthermore, the ferromagnetic resonance peak of the nanocomposites was not observed up to 9 GHz.

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Qian, Yu, Zhun Cheng, and Zhixiong Lu. "Bench Testing and Modeling Analysis of Optimum Shifting Point of HMCVT." Complexity 2021 (May 4, 2021): 1–13. http://dx.doi.org/10.1155/2021/6629561.

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The unreasonable shift point will cause a large shift impact, which will affect the engine fuel economy and the service life of the wet clutch. To decrease shift impact on agricultural tractors with HMCVT (Hydromechanical Continuously Variable Transmission) and find the best working point, the following methods are proposed in this paper: firstly, conducting all-factor method and response surface method (RSM) to design and carry out bench test of shift impact; secondly, using the basic linear fitting, RSM, and stepwise regression analysis to establish comprehensive mathematical models and selecting models with high prediction accuracy; thirdly, putting forward the method of determining the weight of variance to match parameters of three quality evaluation indexes with inconsistent correlation; finally, establishing the total shift quality evaluation index and obtaining the optimal shift working point. It is found that oil filling pressure has a significant effect on speed drop, while the engine speed has a significance on the dynamic load and sliding friction. To make the transmission section of the best quality, the oil pressure at this time is 1 MPa and the engine speed is 1040 r/min. The results show that the proposed method can determine the optimal shift point and provide a reference for developing the control strategy.

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Kao, Tz-Ching, and Linda Thibodeau. "Electroacoustic evaluation of pediatric-focused hearing assistive devices/systems in different digital signal transmission arrangements." Journal of the Acoustical Society of America 146, no. 4 (October 2019): 2917. http://dx.doi.org/10.1121/1.5137121.

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Lopes, Ana Paula G., and Paulo R. L. Gondim. "Low-Cost Authentication Protocol for D2D Communication in m-Health with Trust Evaluation." Wireless Communications and Mobile Computing 2020 (October 27, 2020): 1–16. http://dx.doi.org/10.1155/2020/8876807.

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Relay-assisted device-to-device (D2D) communication serves users at the edge of system coverage of 5G networks, enabling communication among sensors and patients’ mobile devices, and improving spectral and power efficiency. The security of D2D-based m-health applications requires attention due to the delicacy of the data treated in the collection, transmission, and storage of information on patients, whose devices must be adequately authenticated. However, traditional authentication and key agreement schemes are not suitable for D2D scenarios, since they might expose patients to security vulnerabilities and lead to an excessive use of resources. This article proposes a secure and lightweight scheme based on Shamir secret sharing for the mutual authentication of m-health devices in relay-assisted D2D communications, which provides security robustness and reduces resources (energy, processing) consumption. The manuscript also addresses the trustworthiness of devices involved in data relay and device discovery procedures.

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Zakaria, Nor Farhani, Shahrir Rizal Kasjoo, Muammar Mohamad Isa, Zarimawaty Zailan, Mohd Khairuddin Md Arshad, and Sanna Taking. "Self-switching diodes as RF rectifiers: evaluation methods and current progress." Bulletin of Electrical Engineering and Informatics 8, no. 2 (June 1, 2019): 396–404. http://dx.doi.org/10.11591/eei.v8i2.1413.

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In the advancement of the Internet of Things (IoT) applications, widespread uses and applications of devices require higher frequency connectivity to be explored and exploited. Furthermore, the size, weight, power and cost demands for the IoT ecosystems also creates a new paradigm for the hardware where improved power efficiency and efficient wireless transmission needed to be investigated and made feasible. As such, functional microwave detectors to detect and rectify the signals transmitted in higher frequency regions are crucial. This paper reviewed the practicability of self switching diodes as Radio Frequency (RF) rectifiers. The existing methods used in the evaluation of the rectification performance and cut-off frequency are reviewed, and current achievements are then concluded. The works reviewed in this paper highlights the functionality of SSD as a RF rectifier with design simplicity, which may offer cheaper alternatives in current high frequency rectifying devices for application in low-power devices.

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Zheng, Lijie, Qingyan Chen, Jian Xu, and Fangliang Wu. "Evaluation of intervention measures for respiratory disease transmission on cruise ships." Indoor and Built Environment 25, no. 8 (July 28, 2016): 1267–78. http://dx.doi.org/10.1177/1420326x15600041.

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Respiratory diseases are common infectious illnesses on cruise ships. This study integrated an individual-to-individual probability model, a susceptible-exposed-infected-recovered epidemic model at the individual scale, and an onboard indoor social contact network model for evaluating the infection risk on a typical cruise ship voyage. The integrated model was validated by data from a previous influenza outbreak and was able to simulate the infection spreading. The model was used to assess the effects of various intervention measures on controlling influenza on a cruise ship with one index passenger. The results show that individuals in crew cabins and restaurants faced the highest infection risk. Increasing the air change rate in some or all locations could reduce the infection risk to some extent. High-efficiency particulate air filters and ultraviolet germicidal irradiation devices in ventilation systems were the most effective measures. Surgical masks worn by crew members or a quarantine of the index passenger and his/her roommate could reduce the attack rate only to a moderate extent.

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Debita, Grzegorz, Przemyslaw Falkowski-Gilski, Marcin Habrych, Bogdan Miedzinski, Bartosz Polnik, Jan Wandzio, and Przemyslaw Jedlikowski. "Subjective and Objective Quality Evaluation Study of BPL-PLC Wired Medium." Elektronika ir Elektrotechnika 26, no. 3 (June 26, 2020): 13–19. http://dx.doi.org/10.5755/j01.eie.26.3.25794.

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This paper presents results of research on the effectiveness of bi-directional voice transmission in a 6 kV mine cable network using BPL-PLC (Broadband over Power Line - Power Line Communication) technology. It concerns both emergency cable state (supply outage with cable shorted at both ends) and loaded with distorted current waveforms. The narrowband (0.5 MHz–15 MHz) and broadband (two different modes, frequency range of 3 MHz–7.5 MHz) transmission efficiency, considered as an objective study, was correlated with the level of noise in the cable for both induction-inductive and mixed capacitive-inductive coupling of the measurement devices and/or modems. The quality of voice transmission, considered as a subjective study, was assessed by a group of 15 people aged between 25 and 35 years old. The test audio signals included samples in 3 languages sourced from ITU (International Telecommunication Union) and processed in 3 bitrates ranging from 8 kbps to 24 kbps.

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Pochi, Daniele, Roberto Fanigliulo, Carlo Bisaglia, Maurizio Cutini, Renato Grilli, Laura Fornaciari, Monica Betto, et al. "Test Rig and Method for Comparative Evaluation of Conventional and Bio-Based Hydraulic Fluids and Lubricants for Agricultural Transmissions." Sustainability 12, no. 20 (October 16, 2020): 8564. http://dx.doi.org/10.3390/su12208564.

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The use of lubricants and hydraulic fluids of both mineral and synthetic origin in agricultural processes could have a deep impact on the environment as a result of their possible dispersion in the ground and aquifers. Replacing them with bio-based fluids, developed to provide good tribological properties and high biodegradability, could contribute to reducing their negative effects. The evaluation of the capacity of such innovative fluids to replace the conventional ones is based on work cycles lasting as long as their lifetime, during which their characteristics must prove to be at least equal to those of the fluids they replace. To shorten the evaluation process, CREA (Consiglio per la Ricerca in Agricoltura e l’analisi dell’economia Agraria) developed a fluid test rig (FTR) and related test method, able to apply severe work cycles on small oil volumes, thereby accelerating the aging of the fluid beyond what typically occurs. This paper reports the results of the tests on FTR’s functionality carried out comparing two UTTO (Universal Tractor Transmission Oil) fluids: a widespread conventional fluid and an experimental vegetable-based oil. The FTR will permit, in a relatively short time, the assessment of the most promising formulations to be tested later under real working conditions, e.g., in agricultural tractors, reducing the risk of damage, before their ultimate introduction into the operating reality.

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Franco Caballero, Pablo Daniel, and Francisco José García Aguilera. "Evaluation for QR codes in environmental museums." Global Journal of Information Technology: Emerging Technologies 9, no. 2 (October 31, 2019): 29–32. http://dx.doi.org/10.18844/gjit.v9i2.4268.

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The continued use of digital devices, such as smartphones and tablets, has substantially changed the way we communicate and acquire knowledge. Museums are a key element in our society and a source of culture. Updating the method of transmission of museum culture is needed, so technologies related to the Internet have been integrated into the exposed elements. One of the most widespread methods among innovation trends in museums is the use of Quick Response (QR) codes for the transmission of additional information to the exposed elements. The case of the Alborania Museum, being a museum of environmental education, has live animals in veterinary treatment, so the information on the available animals is constantly changing. Establishing posters would have an environmental impact that is against the museum's ethics, so QRs are the best way to present dynamic content with low environmental impact. This article proposes an evaluation of an educational innovation project in the Alborania Museum of Malaga through the Contribution Analysis, in order to verify the value of QR codes as an improvement in the transmission of environmental education. The results show a very good acceptance and usability in this museistic context. The conclusions of this study are relevant to the optimisation of environmental museum information. Keywords: QR code, museum, evaluation, contribution analysis, ICT, environmental education.

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Liu, Jingshen, Jianfeng Zheng, Qingyan Wang, Wolfgang Kainz, and Ji Chen. "A Transmission Line Model for the Evaluation of MRI RF-Induced Fields on Active Implantable Medical Devices." IEEE Transactions on Microwave Theory and Techniques 66, no. 9 (September 2018): 4271–81. http://dx.doi.org/10.1109/tmtt.2018.2851975.

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Lukova-Chuiko, Natali, Volodymyr Nakonechnyi, Volodymyr Saiko, and Serhii Toliupa. "SYNTHESIS OF METHODS OF EVALUATION OF ELECTROMAGNETIC COMPATIBILITY OF RADIO-TECHNICAL SYSTEMS." Information systems and technologies security, no. 1 (1) (2019): 57–65. http://dx.doi.org/10.17721/ists.2019.1.57-65.

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Modern development of radio equipment is characterized by an increase in the speed of processes of transmission and processing of information, miniaturization and integration into unified complexes that physically bridles the sources and receptors of interference. All this leads to the strengthening of the requirements to ensure compliance with the conditions of electromagnetic compatibility and the need for its evaluation at the design stage of radio engineering devices and systems, because the incomplete or incorrect assessment of these requirements leads to a significant increase in time and material costs of the manufacturer, for further development of the development of electronic equipment and reduction its competitiveness. Widespread use of different purposeful electronic means leads to an increase in the levels of electromagnetic fields created by them in the surrounding space. These fields are obstacles for other similar devices, may degrade the operating conditions and reduce the effectiveness of their use. In this process, it is easy to see the characteristic features of dialectical development - progress in this area is restrained by the negative phenomena generated by its development. Further progress requires the overcoming of this trend, that is, development on a new quality level, which is to ensure the joint operation of various means. The key is that the actions of the electromagnetic fields, which are created by some technical means to the other, are carried out for the transmission of information, its processing, or vice versa, violation of the process of transmission and processing of data. Therefore, an analysis is proposed that allows preliminary prediction of the fulfillment of the conditions of electromagnetic compatibility in a group of radio-electronic means that have a number of sources of interference and radio engineering devices on which they affect. In this case, the important issue of checking the provision of electromagnetic compatibility of radio-electronic means is to determine the magnitude of the permissible power at which provides electromagnetic compatibility. The purpose of this article is to consider, from the general positions, the main tasks of the analysis and evaluation of the electromagnetic compatibility of radio-electronic means

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Shrimpton, Nicole Y. R. "Evaluation of disinfection processes for water heater devices used for extracorporeal life support." Perfusion 34, no. 5 (January 11, 2019): 428–32. http://dx.doi.org/10.1177/0267659118819931.

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The Maquet Heater Unit 35 (HU35) is widely used to maintain patient body temperature during extracorporeal life support. Water is used as a medium for heat transfer though it also provides a medium for the growth of pathogens. Thus, the use of a heating unit presents a risk for transmission of water-borne pathogens in critically ill patients. Recently, a Mycobacterium chimaera outbreak in cardiac surgery has been linked to the production of bioaerosols by heater-cooler devices. Consequently, manufacturers have revised cleaning recommendations, with significant impact on staff, budget and environment. Heterotrophic plate counts (HPC) and non-tuberculous mycobacterium growth were assessed following three disinfection processes over a 16-month period. It was found that water quality was acceptable in HU35s when disinfecting with a lower concentration of Chloramine-T than currently recommended, provided exposure of the device to potential pathogens was minimised by the use of a 0.2 μm water filter.

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Fedorenko, V. F., and V. E. Tarkivskiy. "Digital Wireless Technology to Measure Agricultural Performance." Agricultural Machinery and Technologies 14, no. 1 (March 24, 2020): 10–15. http://dx.doi.org/10.22314/2073-7599-2020-14-1-10-15.

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When testing agricultural machinery in order to determine its functional indicators, the ability to wirelessly transmit data between sensors, measuring and information systems are important. (Research purpose) To develop methods and create wireless digital devices for determining the functional indicators of agricultural tractors and machines with the ability to wirelessly transmit data to a remote control point in real time. (Materials and methods) The authors assumed that it was possible to determine the slipping of driving wheels using an inertial navigation system. It was found that in order to calculate real-time indicators obtained using wireless technologies, it was necessary to determine the characteristics of the input signals of discrete sensors on the side of the measuring system. (Results and discussions) The authors substantiated a method for determining the period of incoming signals of discrete sensors with an accuracy of 0.001 seconds for wireless information transmission. They proposed the design of a slipping sensor for an energy vehicle driving wheels, the main element of which is an inertial wheel position sensor. They developed a discrete signal input module and an inertial slipping sensor with the possibility of wireless data transmission based on a radio system with a carrier frequency of 433 megahertz. During field tests, it was found that the accuracy of determining slippage using the inertial wireless sensor IP-291 does not exceed 1 percent; the range of stable radio communication from the tested object to the test control center reaches 1000 meters; the current indicators obtained through digital radio communication did not differ from the indicators obtained in the tractor cab. (Conclusions) The authors worked out an effective system for wireless information transfer with the ability to calculate the performance of the tested equipment in real time.

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Darroudi, Seyed Mahdi, and Carles Gomez. "Experimental Evaluation of 6BLEMesh: IPv6-Based BLE Mesh Networks." Sensors 20, no. 16 (August 17, 2020): 4623. http://dx.doi.org/10.3390/s20164623.

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Bluetooth Low Energy (BLE) has become a major wireless technology for the Internet of Things (IoT). Recent efforts of academia, industry and standards development organizations have focused on creating BLE mesh network solutions. 6BLEMesh is a specification being developed by the IETF that defines an IPv6-oriented approach for BLE mesh networking. In this paper, we perform an experimental evaluation of 6BLEMesh, based on a real implementation. We evaluate latency, round trip time (RTT) and energy consumption. For the latter, we model the device current consumption, we determine the energy efficiency of communication, and we obtain the theoretical device lifetime (for battery-operated devices), for three different hardware platforms. Under the assumptions in our study (including a simple 235 mAh battery, and periodic data transmission), the maximum, asymptotic, device lifetime is 573 days, whereas battery-operated router devices can also achieve 3-digit lifetimes (in days) in many scenarios. Our results also illustrate the impact on performance of BLE-level and application-level parameter settings, adaptation layer mechanisms such as IPv6 header compression, and device hardware characteristics.

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Jurado Murillo, Felipe, Juan Sebastián Quintero Yoshioka, Andrés David Varela López, Ricardo Salazar-Cabrera, Álvaro Pachón de la Cruz, and Juan Manuel Madrid Molina. "Experimental Evaluation of LoRa in Transit Vehicle Tracking Service Based on Intelligent Transportation Systems and IoT." Electronics 9, no. 11 (November 19, 2020): 1950. http://dx.doi.org/10.3390/electronics9111950.

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Long-range (LoRa) technology is a low power wide area network (LPWAN) technology that is currently being used for development of Internet of things (IoT)-based solutions. Transit transport, mainly in medium-sized cities where transit vehicles do not have exclusive lanes, is a service that can be improved with a tracking service using technology such as LoRa. Although some proposals exist, there is not enough experimental information to validate the LoRa technology as adequate. This article: (a) evaluates the operation of LoRa technology in a transit vehicle tracking service in a medium-sized city, based on an Intelligent Transportation Systems architecture and IoT; and (b) investigates optimal LoRa technology configuration parameters for the service. Experiments were performed in a semi-controlled environment using LoRa devices and a gateway, by measuring the received packets and the receive signal strength indicator (RSSI) and modifying: (a) distance; (b) number of devices; and (c) the main LoRa transmission parameters. Obtained results show the ideal values of parameters vary considerably with distance and number of devices used. There were very few settings of the experiments in which the RSSI and packet levels were adequate while distance and number of devices were both changed.

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Hujo, Lubomir, Jozef Nosian, Marcin Zastempowski, Jan Kosiba, Jerzy Kaszkowiak, and Matej Michalides. "Laboratory tests of the hydraulic pump operating load with monitoring of changes in the physical properties." Measurement and Control 54, no. 3-4 (February 2, 2021): 243–51. http://dx.doi.org/10.1177/0020294020983385.

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The present article deals with the physical properties monitoring of the transmission-hydraulic fluid, and changes of those properties due the operating load of the hydraulic pump in laboratory conditions. Tests of the transmission-hydraulic fluid were performed in laboratory conditions with the simulation of the operating load, so as to simulate the real conditions under which hydraulic circuit of the agricultural tractors operates. The universal transmission-hydraulic fluid was subjected to analysis, where the samples of the fluid were taken sequentially according to the chosen methodology at intervals of 250 and 500 h. The results of the present article include the evaluation of the physical properties of the fluid and the flow efficiency change of the hydraulic pump after 250 and 500 h of operation, while simulating the operation load. Based on a laboratory test, we found that after working for 500 h, the dynamic viscosity of the examined hydraulic fluid at 40°C decreased by 2.92 mPa.s and at 100°C decreased by 0.64 mPa.s. When determining the kinematic viscosity of the hydraulic fluid after working for 500 h, we recorded its decrease, namely, at a temperature of 40°C by a value of 3.37 mm2/s and at a temperature of 100°C, its value decreased by 0.77 mm2/s. In the analysis of the test oil samples, we found that the level of water contamination of the hydraulic fluid decreases with increasing number of hours worked. Specifically, the water concentration in the hydraulic fluid decreased by 0.031%. At the same time, we recorded a slight decrease in the flow efficiency of the hydraulic pump, specifically by a value of 0.03% after 500 h worked. After working 500 h, we found that the range of abrasion particles in the transmission-hydraulic fluid is within the prescribed range, which is determined by the standard D6595-00.

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Dang, Nhan Tam, Hai-Duong Le, Son Thanh Le, and Ha Manh Tran. "Applying attribute-based encryption on mobile devices." Science & Technology Development Journal - Engineering and Technology 3, SI1 (September 19, 2020): First. http://dx.doi.org/10.32508/stdjet.v3isi1.518.

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The 21st century has witnessed the rapid development of small and convenient mobile devices such as smartphones, tablets, game players, sensor nodes, etc. The rise of such mobile devices indicates the increase of colossal data transmission through the Internet and online services along with the challenges of data security. It is common to think of a solution to protect sensitive data from unauthorized users, and the most popular solution is to use encryption. While many research activities in functional encryption have widely been applied to network devices, computers, and applications, mobile devices still attract much attention to security issues due to the limitations of system resources, connectivity, data transmission and power consumption that malicious users can exploit to launch attacks. Especially, mobile devices have become a principal tool to share data on the Internet through online services, such as Facebook, Youtube, DropBox, Amazon, Online Games, etc. This paper presents a study of the Attribute-Based Encryption (ABE) scheme that exploits user attributes to build the secret key and the ciphertext. ABE encryption is specified by a set of attributes or a policy defining attributes that users possess. The paper also describes a few implementations of ABE applied in the cryptography community and the challenges of integrating ABE into real-world applications. Finally, the paper proposes an implementation of ABE for Android mobile devices. This implementation associated with the Kerberos protocol can be applied to secured data sharing applications. The Kerberos protocol aims at providing mutual authentication for the client server model. Experiments have evaluated the proposed ABE implementation on Android mobile devices along with the Kerberos system. The evaluation also includes ABE performance with discussions and lessons learned.

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Tan, Kian Lam, Chen Kim Lim, and Abdullah Zawawi Talib. "Tile-Based Panoramic View in Mobile Devices." Applied Mechanics and Materials 284-287 (January 2013): 3487–91. http://dx.doi.org/10.4028/www.scientific.net/amm.284-287.3487.

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Cylindrical panoramic view is a 360-degrees horizontal representation of a certain scene. The user can navigate interactively through the scene and change their view angles. Basically, panoramic views are often high-resolution, high-definition and consume a significant amount of bandwidth for transmission through Internet in mobile platform. In this paper, a method is proposed by combining a proposed tile-based algorithm with scrollViewDidScroll protocol of the iOS platform. With the tile-based algorithm, the panoramic views are divided into tiles and only tiles of interest are viewed on the mobile screen. Besides, the scrollViewDidScroll protocol of the iOS platform is used to link back the end of panoramic view with the start of the panoramic view to produce a cylindrical panoramic view. From here, the user can view the same output as panoramic views on a mobile device but using limited bandwidth, memory, and number of processors. Based on the evaluation, the respondents gave favorable response to the method.

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Zhao, Qing Qi, Hong Hao Zhao, Fan Bo Meng, and Zhen Jiang Lei. "Performance Evaluation of ZigBee Routing Algorithms in Smart Grid." Applied Mechanics and Materials 336-338 (July 2013): 2428–32. http://dx.doi.org/10.4028/www.scientific.net/amm.336-338.2428.

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In order to meet the requirements of Smart Grid in data acquisition, transmission reliability, stability, robustness and low power consumption of devices, ZigBee with its significant advantages of low power, low cost, low rate and easy to use, can play an important role in Smart Grid. As one of the key technologies of ZigBee, routing technology plays an important role in the performance optimization of network. Thus, in this paper, we focus on cluster-tree routing algorithm and hybrid routing algorithm in ZigBee network. Simulation and results show that, hybrid routing algorithm has better performance than cluster-tree routing algorithm in network throughput, average traffic received, average number of hops, network delay and network load.

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Ji, Ruiwen, Yuanlong Cao, Xiaotian Fan, Yirui Jiang, Gang Lei, and Yong Ma. "Multipath TCP-Based IoT Communication Evaluation: From the Perspective of Multipath Management with Machine Learning." Sensors 20, no. 22 (November 18, 2020): 6573. http://dx.doi.org/10.3390/s20226573.

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With the development of wireless networking technology, current Internet-of-Things (IoT) devices are equipped with multiple network access interfaces. Multipath TCP (MPTCP) technology can improve the throughput of data transmission. However, traditional MPTCP path management may cause problems such as data confusion and even buffer blockage, which severely reduces transmission performance. This research introduces machine learning algorithms into MPTCP path management, and proposes an automatic learning selection path mechanism based on MPTCP (ALPS-MPTCP), which can adaptively select some high-quality paths and transmit data at the same time. This paper designs a simulation experiment that compares the performance of four machine learning algorithms in judging path quality. The experimental results show that, considering the running time and accuracy, the random forest algorithm has the best performance in judging path quality.

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Pryadkin, Vladimir, Ivan Bartenev, and Viktor Posmetev. "EVALUATION OF SUSTAINABILITY AND ECOLOGICAL PROPERTIES OF A ROBOTIZED STUMP REMOVER EQUIPPED WITH WIDE-SECTION TYRES." Forestry Engineering Journal 10, no. 1 (April 6, 2020): 244–55. http://dx.doi.org/10.34220/issn.2222-7962/2020.1/18.

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The article analyzes the technical means for uprooting trees. Tools aggregated with wheel and caterpillar tractors of various traction classes are the most popular ones in Russia. Abroad, self-propelled stump removers with high engine power and high performance are used, which are in demand in various industries (forestry, agricultural and oil and gas complexes, road construction), when laying high-voltage power lines and their maintenance, as well as in other areas of the national economy. The analysis of technical means for uprooting trees has shown that the dominant trend is creation of stump removers that ensure safety of the process, its high productivity and decrease in the number of personnel on felling. Self-propelled robotic stump remover equipped with wide-profile low-pressure tires has been developed to implement innovative technologies in the forest complex. Ensuring the technological process is carried out by robot-eradicator in unmanned mode. It is achieved by using a technical vision system, navigation equipment, automated control of technological equipment, transmission and steering. The aim of the study was to evaluate the longitudinal stability of a robotic self-propelled stump remover during vertical transportation of a tree and environmental compatibility of its wheeled mover with soil and vegetation cover. Conducted theoretical studies have found that the proposed layout scheme of a self-propelled stump remover provides longitudinal stability when moving with a tree in an upright position without the use of ballast counterweights behind the rear axle. It was also found that the wheel mover of the stump remover equipped with wide-profile low-pressure tires is environmentally friendly when performing technological operations in the summer-autumn period

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Liu, Jingshen, Jianfeng Zheng, Qingyan Wang, Wolfgang Kainz, and Ji Chen. "Erratum to “A Transmission Line Model for the Evaluation of MRI RF-Induced Fields on Active Implantable Medical Devices”." IEEE Transactions on Microwave Theory and Techniques 68, no. 6 (June 2020): 2468. http://dx.doi.org/10.1109/tmtt.2020.2978598.

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Hull, Robert. "Microstructural evaluation of optical materials and devices using a combination of focused ion beam sputtering and transmission electron microscopy." Optical Materials 6, no. 1-2 (July 1996): 1–11. http://dx.doi.org/10.1016/0925-3467(96)00023-7.

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Kwok, Coco Yin Tung, Man Sing Wong, Sion Griffiths, Fiona Yan Yan Wong, Roy Kam, David C. W. Chin, Guanjing Xiong, and Esmond Mok. "Performance Evaluation of iBeacon Deployment for Location-Based Services in Physical Learning Spaces." Applied Sciences 10, no. 20 (October 13, 2020): 7126. http://dx.doi.org/10.3390/app10207126.

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Bluetooth Low Energy (BLE) is a wireless network technology used for transmitting data over short distances. BLE maintains a data transmission range comparable to the regular Bluetooth transmission, but consumes less energy and cost. iBeacon technology refers to BLE mobile devices, which allow mobile applications to receive signals from iBeacons in both indoor and outdoor environments. It is commonly used nowadays for positioning, location services, navigation and marketing, for the sustainable development of smart cities. The applications, however, can be further enhanced for use in many disciplines, such as education, health sector, and exhibitions for disseminating information. This study performed a set of robustness and performance tests on BLE-based iBeacons in the teaching and learning environments to evaluate the performance of iBeacon signals for positioning. During robustness testing, positioning accuracy, signal availability and stability were assessed under different environmental conditions, and the findings suggested pedestrian traffic blocking the line of sight between iBeacon and receiver, causing the most signal attenuations and variation in RSSI. In performance testing, a series of tests was conducted to evaluate the deployment of the iBeacons for positioning; leading to recommendations of iBeacon deployment location, density, transmission interval, fingerprint space interval and collection time in physical learning spaces for sustainable eLearning environments.

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Colangeli, Sergio, Riccardo Cleriti, Walter Ciccognani, and Ernesto Limiti. "Evaluation of coaxial cable performance under thermal gradients." International Journal of Microwave and Wireless Technologies 7, no. 3-4 (March 30, 2015): 239–49. http://dx.doi.org/10.1017/s1759078715000069.

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This paper presents a very flexible tool for numerically evaluating the small-signal and noise parameters of a transmission line subject to an arbitrary thermal gradient. Contrary to previous methods, the proposed approach allows straightforwardly taking into account possible variations of electrical parameters along the propagation direction, such as may be expected when temperature ranges between very different values. The main application of the proposed method is cable modeling in noise-figure measurement setups under cryogenic operation: in such circumstances, indeed, the coaxial cables (or waveguide) at the interface between the outside and the inside of the cryogenic chamber are subject to remarkable temperature excursions. As a consequence, significant de-embedding errors may arise if the cables are not correctly modeled, given the very low values of noise figure which are commonly exhibited by cryo-cooled active devices.

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Oh, Hayoung. "Security-aware fair transmission scheme for 802.11 based cognitive IoT." International Journal of Electrical and Computer Engineering (IJECE) 10, no. 3 (June 1, 2020): 2589. http://dx.doi.org/10.11591/ijece.v10i3.pp2589-2599.

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Cognitive IoT is exponentially increased because of various real time and robust applications with sensor networks and big data analysis. Each IoT protocol of network layer can be RPL, COAP and so on based on IETF standards. But still collision problems and security-aware fair transmission on top of scalable IoT devices were not solved enough. In the open wireless LAN system based cognitive IoTs, IoT node that is continuously being stripped of its transmission opportunity will continue to accumulate packets to be sent in the butter and spoofing attacks will not allow the data transfer opportunities to be fair. Therefore, in this paper, we propose a method to reduce the average wait time of all packets in the system by dynamically controlling the contention window (CW) in a wireless LAN based cognitive IoT environment where there are nodes that do not have fair transmission opportunities due to spoofing attacks. Through the performance evaluation, we have proved that the proposed technique improves up to 80% in terms of various performance evaluation than the basic WLAN 802.11 based IoT.

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Madhu, Mr B. "Reliability Evaluation of Bulk Power Systems Incorporating UPFC." International Journal for Research in Applied Science and Engineering Technology 9, no. VI (June 25, 2021): 2339–47. http://dx.doi.org/10.22214/ijraset.2021.35505.

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Unified power flow controller (UPFC) is one of the most advanced flexible AC transmission system (FACTS) devices that can simultaneously and independently control both the real and reactive power flow in a transmission line. The utilization of UPFC can result in significant reliability benefits in modern power systems. This paper proposes a novel reliability network model for a UPFC, which incorporates the logical structure and the distinct operating modes of a UPFC. Two-state or three-state models have been used for UPFC by previous researchers. The proposed model divides the UPFC operating modes into four states, namely the UPFC up state, STATCOM state, SSSC state and UPFC down state, in order to improve the accuracy of the model by recognizing the practical operating states of a UPFC. The new model also incorporates an AC flow-based optimal load shedding approach to assess the impact of bus voltages and reactive power flow on UPFC in order to decide appropriate load curtailment in the reliability evaluation process. The performance of the proposed model is verified using a test system, and compared with different reliability models of UPFC. Various operating schemes, such as different placement locations of UPFC, and different capacities of UPFC are used to illustrate the advantages of the developed models, and to examine the impacts of UPFC on the system reliability.

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Nikodem, Maciej, and Marek Bawiec. "Experimental Evaluation of Advertisement-Based Bluetooth Low Energy Communication." Sensors 20, no. 1 (December 23, 2019): 107. http://dx.doi.org/10.3390/s20010107.

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This paper addresses the efficiency of Bluetooth Low Energy (BLE) communication in a network composed of a large number of tags that transmit information to a single hub using advertisement mode. Theoretical results show that the use of advertisements enables hundreds and thousands of BLE devices to coexist in the same area and at the same time effectively transmit messages. Together with other properties (low power consumption, medium communication range, capability to detect a signal’s angle-of-arrival, etc.), this makes BLE a competing technology for the Internet of Things (IoT) applications. However, as the number of communicating devices increases, the advertisement collision intensifies and the communication performance of BLE drops. This phenomena was so far analyzed theoretically, in simulations and in small-scale experiments, but large-scale experiments are not presented in the literature. This paper complements previous results and presents an experimental evaluation of a real IoT-use case, which is the deployment of over 200 tags communicating using advertisements. We evaluate the impact of the number of advertisements on the effective data reception rate and throughput. Despite the advertisement collision rate in our experiment varying between 0.22 and 0.33, we show that BLE, thanks to the multiple transmission of advertisements, can still ensure acceptable data reception rates and fulfill the requirements of a wide range of IoT applications.

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Unthan, Kristin, Felix Gräf, Marco Laumen, Thomas Finocchiaro, Christoph Sommer, Hermann Lanmüller, and Ulrich Steinseifer. "Design and Evaluation of a Fully Implantable Control Unit for Blood Pumps." BioMed Research International 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/257848.

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As the number of donor hearts is limited while more and more patients suffer from end stage biventricular heart failure, Total Artificial Hearts become a promising alternative to conventional treatment. While pneumatic devices sufficiently supply the patients with blood flow, the patient’s quality of life is limited by the percutaneous pressure lines and the size of the external control unit. This paper describes the development of the control unit of the ReinHeart, a fully implantable Total Artificial Heart. General requirements for any implantable control unit are defined from a technical and medical point of view: necessity of a Transcutaneous Energy Transmission, autonomous operation, safety, geometry, and efficiency. Based on the requirements, a prototype is designed; it incorporates a LiFePo4battery pack with charger, a rectifier for transcutaneous energy transmission, the motor’s driver electronics, and a microcontroller which monitors and controls all functions. In validation tests, the control unit demonstrated a stable operation on TET and battery supply and a safe switching from one supply to the other. The overall mean efficiency is 14% on TET and 22% on battery supply. The control unit is suitable for chronic animal trials of the ReinHeart.

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Guo, Qingjie, Fengxu Yang, and Jianming Wei. "Experimental Evaluation of the Packet Reception Performance of LoRa." Sensors 21, no. 4 (February 4, 2021): 1071. http://dx.doi.org/10.3390/s21041071.

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LoRa technology is currently one of the most popular Internet of Things (IoT) technologies. A substantial number of LoRa devices have been applied in a wide variety of real-world scenarios, and developers can adjust the packet reception performance of LoRa through physical layer parameter configuration to meet the requirements. However, since the important details of the relationship between the physical layer parameters and the packet reception performance of LoRa remain unknown, it is a challenge to choose the appropriate parameter configuration to meet the requirements of the scenarios. Moreover, with the increase in application scenarios, the requirements for energy consumption become increasingly high. Therefore, it is also a challenge to know how to configure the parameters to maximize the energy efficiency while maintaining a high data rate. In this work, a complex evaluation experiment on the communication capability under a negative Signal to Noise Ratio is presented, and the specific details of the relationship between physical layer parameters and the packet reception performance of LoRa are clarified. Furthermore, we study the impact of the packet length on the packet reception performance of LoRa, and the experimental results show that when there is a large amount of data to be transmitted, it is better to choose long packets instead of short packets. Finally, considering the influence of physical layer parameters and the packet length on the packet reception performance of LoRa, the optimal parameter combination is explored, so as to propose a transmission scheme with a balanced reliability, delay, and energy consumption. This scheme is the first to consider the physical layer parameters and packet length together to study the communication transmission scheme, which reduces the communication time by 50% compared with the traditional transmission scheme and greatly reduces the energy consumption.

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Journal articles on the topic 'Tractors – Transmission devices – Evaluation'

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