Frame Time Research Articles

Visions of the good future

Abstract The relationship between time and politics is complex and multilayered, especially in issues such as global warming. This facilitates political playing with and about time; political actors use and frame time in various ways. Drawing upon the work of Reinhart Koselleck, this article examines temporal statements about the environment and the climate in Swedish election campaigns 1988 to 2018 and shows how political rhetoric has been constituted by several competing modalities of time. However, these modalities can become problematic for political thinking about the future. To resolve the climate crisis, we need a politics that acknowledges both historical and political contingency. Engaging with the past, without seeking to extrapolate a unified narrative of historical progress, explores the past from various perspectives and shows how the present is contingent. This could enable a renegotiation of possible futures and a politics for the future that facilitates both understanding and action.

Distal tibial osteotomy compared to proximal osteotomy for limb lengthening in children.

The aim of this retrospective cohort study was to assess and investigate the safety and efficacy of using a distal tibial osteotomy compared to proximal osteotomy for limb lengthening in children. In this study, there were 59 consecutive tibial lengthening and deformity corrections in 57 children using a circular frame. All were performed or supervised by the senior author between January 2013 and June 2019. A total of 25 who underwent a distal tibial osteotomy were analyzed and compared to a group of 34 who had a standard proximal tibial osteotomy. For each patient, the primary diagnosis, time in frame, complications, and lengthening achieved were recorded. From these data, the frame index was calculated (days/cm) and analyzed. All patients ended their treatment with successful lengthening and deformity correction. The frame index for proximal versus distal osteotomies showed no significant difference, with a mean 48.5 days/cm (30 to 85) and 48.9 days/cm (28 to 81), respectively (p = 0.896). In the proximal osteotomy group, two patients suffered complications (one refracture after frame removal and one failure of regenerate maturation with subsequent valgus deformity) compared to zero in the distal osteotomy group. Two patients in each group sustained obstacles that required intervention (one necessitated guided growth, one fibula lengthening, and two required change of wires). There was a similar number of problems (pin-site infections) in each group. Our data show that distal tibial osteotomies can be safely employed in limb lengthening for children using a circular frame, which has implications in planning a surgical strategy; for example, when treating a tibia with shortening and distal deformity, a second osteotomy for proximal lengthening is not required.Cite this article: Bone Joint J2022;104-B(11):1273-1278.

Definitive Taylor Spatial Frame management for the treatment of high-energy open tibial fractures: Clinical and patient-reported outcomes

BackgroundHigh energy open tibial fractures are complex injuries with no consensus on the optimal method of fixation. Treatment outcomes are often reported with union and re-operation rates, often without specific definitions being provided. We sought to describe union, reoperation rates, and patient reported outcomes, using the validated EQ-VAS and Disability Rating Index (DRI) scores, following stabilisation with a Taylor Spatial Frame (TSF) and a combined orthoplastic approach for the management of soft tissues. A literature review is also provided. MethodA prospective cross-sectional follow up of open tibial fractures, treated at a level 1 major trauma centre, managed with a TSF using a one ring per segment technique between January 2014 and December 2019 were identified. Demographic, injury and operative data were recorded, along with Patient Reported Outcome Measures (PROM) scores, specifically the EQ-VAS and Disability Rating Index (DRI). Union rates, defined by radiographic union scale in tibia (RUST) scores, and re-operation rates were recorded. Appropriate statistical analyses were performed, with a p<0.05 considered statistically significant. ResultsOverall, 51 patients were included. Mean age was 51.2 ± 17.4 years, with a 4:1 male preponderance. Diaphyseal and distal fractures accounted for 76% of cases. Mean time in frame was 206.7 ± 149.4 days. Union was defined and was achieved in 41/51 (80.4%) patients. Deep infection occurred in 6/51 (11.8%) patients. Amputation was performed in 1 case (1.9%). Overall re-operation rate was 33%. Time to union were significantly longer if re-operation was required for any reason (uncomplicated 204±189 vs complicated 304±155 days; p = 0.0017) . EQ-VAS and DRI scores significantly deteriorated at 1 year follow-up (EQVAS 87.5 ± 11.7 vs 66.5 ± 20.4;p<0.0001 and DRI 11.9 ± 17.8 vs 39.3 ± 23.3;p<0.0001). At 1 year post op, 23/51(45.1%) required a walking aid, and 17/29 (58.6%) of those working pre-injury had returned to work. ConclusionOpen tibial fracture have significant morbidity and long recovery periods as determined by EQVAS and DRI outcome measures. We report the largest series of open tibial feature treated primarily with a TSF construct, which has similar outcomes to other techniques, and should therefore be considered as a useful technique for managing these injuries.

Evaluation of Perceptual Difference in Dynamic Projection Mapping with and without Movement of the Target Surface

High-frame-rate visual feedback has been proven effective for projection mapping on quickly moving targets. However, the quantitative conditions of frame rates have not been elucidated. In particular, considering that the human dynamic visual acuity generally declines as the moving target velocity increases, it may be argued that the tracking accuracy required for projection mapping on moving targets can be lower than that required for fixed targets. To examine the above-mentioned conditions of frame rates, this study compares them based on two types of projection mapping systems having equivalent relative movements to each other: projection mapping from a fixed projector/camera system to a moving target and projection mapping from a moving projector/camera system to a fixed target. We examined the effects of the target movements by having stationary observers visually recognize and evaluate them. Using the weighted up-down method, we measured the frame time that provides a just noticeable difference (JND) to the projection mapping. We found that when the visual feedback is generated at a frame time of 2 ms, the frame time that provides a JND is 3.72 ms on average for fixed targets and 3.94 ms on average for moving targets: a 1%-level significant difference. Taking the individual differences and experimental errors into account, this is not a very large variation. This suggests that, in projection mapping to moving targets, we should realize a tracking accuracy as precise as that in projection mapping to fixed targets.

Solid-state 13C NMR study of annealing effect on the crystalline phase of poly(ethylene-co-methacrylic acid) ionomers

Annealing effect at 65 °C on the crystalline phase of Poly (ethylene-co-methacrylic acid) (EMAA) and the EMAA ionomer neutralized with Na+ cation (EMAA54Na: 54% of carboxy groups is neutralized) were mainly investigated by the solid-state 13C CP and DPMAS NMR. The 13C NMR spectra revealed the increase of Orthorhombic crystalline phase by annealing at 65 °C, while the Monoclinic crystalline phase unchanged. In addition, no appreciable changes were detected on carboxy groups. The crystallinity estimated from the 13C DPMAS NMR for EMAA did not increase (from 19% to 20%) after annealing, while that for EMAA54Na increased from 12% to 17%. The ratio of Monoclinic/Orthorhombic = 40/60 for EMAA did not change after annealing, whereas the ratio for EMAA54Na became 30/70 from 40/60. From the variable-temperature solid-state 13C CPMAS NMR measurements, it was suggested that the Monoclinic crystalline phase begins to melt beyond 55 °C, while the Orthorhombic crystal remained; the temperature was close to the Ti endothermic transition (so-called the order-disorder transition). Furthermore, the 13C spin-lattice relaxation time in the laboratory frame (T1C) of the Orthorhombic crystalline phase became significantly long after annealing, while that of the Monoclinic crystalline phase was not altered drastically. Similarly, the T1C of the amorphous phase was not affected by annealing. These observations suggested that the interaction between Na+ cations and carboxy groups in EMAA ionomers limits crystal growth of polyethylene, and the Ti is mainly caused by the melting of Monoclinic crystal.

Suitable Homework Boosts Highschool Learning Effects

Highschool homework as an integral part of the study skills benefits students' learning outcomes significantly. Consistency of completing homework contributes to rising scores in any given assignment such as quizzes, regular tests, standardized tests, etc. The purpose of homework aims at different targets and it is designed for specific groups and occasions. Generally, there are four types of homework: a) Practice, b) Preparatory, c) Extension, and d) Integration. On the other hand, there is a great variety of homework with various tasks. The daily length of the high school assignments is within the frame time of ninety minutes to three hours. Too long or too short time consuming on completing the task does not result effectively in positive learning outcomes. The optimal time for completing an assignment resonates with the Aristotle mean, and it provides maximum benefits in learning outcome. Despite the fact of the dispute between education stockholders on benefits of homework, they still agree that homework elevates study skills to a certain degree with regard to the exams or study skills.

TECHNICAL AND ECONOMIC ASPECTS OF THE RECONSTRUCTION OF UKRAINIAN THERMAL POWER PLANTS IN THE CONTEXT OF INCREASING THE COST OF CO2 EMISSIONS

The efficiency of investments in the thermal energy of Ukraine to reduce carbon dioxide emissions in the conditions of increasing the tariff for CO2 emissions is analyzed. Assuming a linear increase in the tariff, the relationship between the levelized cost of energy of thermal power plants (LCOE) with the growth rate of the emission tariff, technical parameters of thermal power plants, time frame and interest rate of the project. For different types of thermal power plants, grouped by the value of the coefficient of conversion of thermal energy into electricity, the reduced cost of electricity in medium-term and long-term projects using the main fuels. The level of profitable investments in the reconstruction of thermal power plants is estimated at the increase of the tariff for carbon dioxide emissions. High efficiency of TPP reconstruction in medium-term projects is substantiated, which allows to achieve significant reduction of gross CO2 emissions with constant production volume and constant value of LCOE. The efficiency of investments in the reconstruction of thermal energy and in renewable energy to reduce CO2 emissions is compared. It has been shown that investments in the reconstruction of thermal power plants give the greatest reduction in CO2 emissions per unit of investment compared to alternative projects. At the same time, the reconstruction of TPPs increases the shunting power in the United Energy System of Ukraine, which will allow more active implementation of renewable energy sources for electricity generation. The possibility of using ammonia as a fuel for thermal power plants to reduce carbon dioxide emissions is discussed. The importance of thermal power plants to ensure the sustainable operation of the United Energy System of Ukraine in today’s conditions is emphasized. Bibl. 18, Fig. 1, Tab. 4.

Intelligent Building Space Layout and Optimization Design Method Based on Biological Population Simulation

Smart buildings can store various types of data, analyze data at a faster speed, and quickly provide users with the most accurate and high-quality intelligent services through technical means. The main purpose is to meet the needs of users, to provide communication and a series of knowledge services for all professional participants, and to provide comfortable working resources and working environment for all professional participants to ensure the smooth implementation of the project and meet the construction engineering requirements. In this study, the spatial layout and optimization of intelligent buildings are carried out based on biological population simulation, and the following conclusions are drawn: (1) The emergence of multicore or multicore graphics converters reduces the cost and popularity of high-performance software platforms, and provides faster computing speeds for applications. A new platform and implementation method have been developed. Comparing marine biopopulation models relies on the i4Ocean platform. The i4Ocean platform is a computer platform for seascape information and virtual reality applications, including view management, production engine, and MVC core framework. (2) The swarm model simulates the movement of fish in a virtual ocean. Determine their behavioral changes based on determined behavioral conditions (e.g., in position, position, and velocity). As everyone in the group moves, the entire group is monitored for behavior. (3) Intelligent buildings involve many aspects of the social machine, such as building construction, which not only affects architecture, but also design. Smart construction helps improve quality, shorten production time, save resources, and control costs. It is an important part of the structural transformation of the supply side of the construction industry, and an important tool for the structural adjustment and modernization of the construction industry and greenhouses. (4) X2View is like the most popular configuration king, with integrated functions. Project software is placed on the X2View and sent to the door or touch screen for processing and monitoring. In the driver configuration interface, you can set the application frame time of the monitoring node and the real-time measurement time of the record value recording time frame.

The Framing of Food Safety Crisis in Chinese Media Discourse: A Case Study of “Unif 100 Instant Noodles”

There have been several cases concerning the food safety crisis in China. In 2022, the Unif 100 Instant Noodles crisis broke out, triggering a heated debate on the Internet. Under the two frameworks, mainstream newspapers and public social media exhibit different characteristics. During the event’s evolution in the three periods, the emphases of the two parties were also different. By trimming and analyzing the reports of China’s mainstream newspapers and the posts of China’s mainstream social platforms, starting from framing analysis and time node analysis, this paper studies the structure and power of contemporary Chinese food safety under different channels.

A Novel Rain Removal Approach for Outdoor Dynamic Vision Sensor Event Videos.

As bio-inspired vision devices, dynamic vision sensors (DVS) are being applied in more and more applications. Unlike normal cameras, pixels in DVS independently respond to the luminance change with asynchronous output spikes. Therefore, removing raindrops and streaks from DVS event videos is a new but challenging task as the conventional deraining methods are no longer applicable. In this article, we propose to perform the deraining process in the width and time (W-T) space. This is motivated by the observation that rain steaks exhibits discontinuity in the width and time directions while background moving objects are usually piecewise smooth along with both directions. The W-T space can fuse the discontinuity in both directions and thus transforms raindrops and streaks to approximately uniform noise that are easy to remove. The non-local means filter is adopted as background object motion has periodic patterns in the W-T space. A repairing method is also designed to restore edge details erased during the deraining process. Experimental results demonstrate that our approach can better remove rain noise than the four existing methods for traditional camera videos. We also study how the event buffer depth and event frame time affect the performance investigate the potential implementation of our approach to classic RGB images. A new real-world database for DVS deraining is also created and shared for public use.

Timely and timeless framing of the new MINI Cooper

This paper presents an exemplary case in the car industry: the design of the new MINI Cooper, released in 2001. Through a semi-structured interview with design expert Frank Stephenson and the use of secondary data, we examine how an expert designer considers time to design a car relevant across decades. We find that the framing of the new MINI Cooper integrates both timely and timeless aspects. In the process, Frank Stephenson draws values, frames and working principles from the present portfolio and competing products to create a succession of product generation. We use this case to argue for the centrality of framing time when striving to create seminal, long-lasting designs. The study identifies ‘the framing of time’ as a main expertise in the car industry. Therefore, this paper answers scholars' calls for more research on how outstanding designers work to consider time (Cross, 2004). • The framing of time is a critical skill for expert automotive designers. • The key steps for framing the design of the new MINI Cooper are analysed. • Timeless designs are anchored in the aspired values and the framing. • Timely designs are based on working principles that respond to the context.

FISI: frequency domain integration sequential imaging at 1.26×1013 frames per second and 108 lines per millimeter.

High spatial resolution on the image plane (intrinsic spatial resolution) has always been a problem for ultrafast imaging. Single-shot ultrafast imaging methods can achieve high spatial resolution on the object plane through amplification systems but with low intrinsic spatial resolutions. We present frequency domain integration sequential imaging (FISI), which encodes a transient dynamic by an inversed 4f (IFF) system and decodes it using optical spatial frequencies recognition (OFR), which overcomes the limitation of the spatial frequencies recognition algorithm. In an experiment on the process of an air plasma channel, FISI achieved shadow imaging of the channel with a framing rate of 1.26×1013 fps and an intrinsic spatial resolution of 108 lp/mm (the spatial resolution on the image plane). Owing to its excellent framing time and high intrinsic spatial resolution, FISI can probe both repeatable and unrepeatable ultrafast phenomena, such as laser-induced damage, plasma physics, and shockwave interactions in living cells with high quality.

Research on the Lightweight Deployment Method of Integration of Training and Inference in Artificial Intelligence

In recent years, the continuous development of artificial intelligence has largely been driven by algorithms and computing power. This paper mainly discusses the training and inference methods of artificial intelligence from the perspective of computing power. To address the issue of computing power, it is necessary to consider performance, cost, power consumption, flexibility, and robustness comprehensively. At present, the training of artificial intelligence models mostly are based on GPU platforms. Although GPUs offer high computing performance, their power consumption and cost are relatively high. It is not suitable to use GPUs as the implementation platform in certain application scenarios with demanding power consumption and cost. The emergence of high-performance heterogeneous architecture devices provides a new path for the integration of artificial intelligence training and inference. Typically, in Xilinx and Intel’s multi-core heterogeneous architecture, multiple high-performance processors and FPGAs are integrated into a single chip. When compared with the current separate training and inference method, heterogeneous architectures leverage a single chip to realize the integration of AI training and inference, providing a good balance of training and inference of different targets, further reducing the cost of training and implementation of AI inference and power consumption, so as to achieve the lightweight goals of computation, and to improve the flexibility and robustness of the system. In this paper, based on the LeNet-5 network structure, we first introduced the process of network training using a multi-core CPU in Xilinx’s latest multi-core heterogeneous architecture device, MPSoC. Then, the method of converting the network model into hardware logic implementation was studied, and the model parameters were transferred from the processing system of the device to the hardware accelerator structure, composed of programmable logic through the bus interface AXI provided on the chip. Finally, the integrated implementation method was tested and verified in Xilinx MPSoC. According to the test results, the recognition accuracy of this lightweight deployment scheme on MNIST dataset and CIFAR-10 dataset reached 99.5 and 75.4% respectively, while the average processing time of the single frame was only 2.2 ms. In addition, the power consumption of the network within the SoC hardware accelerator is only 1.363 W at 100 MHz.

Approach for early-warning collapse of double-span steel portal frames induced by fire

The unexpected collapse of burning buildings has posed a great threat to firefighters. Hence, early-warning methods for fire-induced collapse are urgently needed to avoid secondary casualties. This paper proposes an early-warning approach for predicting the collapse of double-span steel portal frames based on real-time measurement of displacements and displacement velocities of the burning frame. Firstly, numerical models are established to simulate the collapse behavior of double-span steel portal frames under fire, and six collapse modes of the frames are summarized through parametric analysis. The displacements and displacement velocities of the apex, eaves, and mid-span of rafters, defined as the key monitoring physical parameters (KMPPs), are found to have a close relationship with the collapse mode and time of the burning frames. Secondly, by exploring the rules of the KMPP-time curves, the characterized points that can be used for early warning of the collapse of the frame are extracted. Then, the early-warning approach applicable to six collapse modes is proposed based on the emergence of various characterized points. For universalizing the collapse prediction, early-warning time ratios are introduced and determined according to the reliability theory. Finally, the practicability and accuracy of the proposed approach are validated by an existing fire test.

Lane Detection Based on Instance Segmentation of BiSeNet V2 Backbone Network

ABSTRACT Most lane line detection algorithms still have room for improvement in detection accuracy, speed, and robustness. Meanwhile, these algorithms only test the performance indicators through the test set of the open-source dataset rather than deploying them on actual vehicles and evaluating the performance indicators through road scenarios. Therefore, this paper proposes a lane detection algorithm based on instance segmentation. Firstly, a dual-branch neural network model for lane line image segmentation was designed based on BiSeNet V2. Then the discrete lane line feature points are operated through the clustering model. The corresponding feature points are selected for fitting by combining straight lines and curves to obtain the appropriate fitting parameter equation for the specific visual field area. Finally, the model is trained and verified based on the TuSimple dataset. The algorithm has a noticeable performance improvement under the two evaluation indicators of mIoU and FPS. Meanwhile, the model is integrated into the ROS task platform for intelligent vehicles. The results show that the algorithm’s accuracy and detection speed are increased to about 3.9 and 2.9 times, respectively, that of the improved probabilistic Hough transform algorithm under the two evaluation indicators of lateral distance and the detection time of each image frame.

On the linearity of the generalized Lorentz transformation

Lorentz transformations between inertial observers, along with Einstein's theory of special relativity, remedied discrepancies between Newtonian physics and Maxwell's electromagnetism caused by the use of the same time in all inertial frames. In view of the fundamental importance of the relativity between inertial observers, there have been several papers deriving generalized Lorentz transformations without using light. Proving that general transformations are linear in space and time can be done in several ways, most commonly relying on a four-dimensional Minkowski spacetime, but other approaches are possible. A method is presented here that establishes the linearity of the transformation by considering velocity transformations in the light of Einstein's first relativity postulate of 1905. Once linearity is obtained, the remainder is fairly straightforward and parallels results and methods found in the literature.

Effect of VLAN configuration on IEC 61850 sampled values

IEC 61850, the standard for communication in power utility, has solved the interoperability problems between different vendors in substation communication networks (SCNs). However, most studies on SCN that use IEC 61850 were conducted using computer-based simulations or commercial equipment with fixed functions. In this study, an experiment on an SCN was conducted using real equipment such as a network switch, Raspberry Pi, and a mini PC. A cyclic data model was used for the traffic generation of sampled values (SVs) according to IEC 61850. The effect of applying a virtual local area network (VLAN) in the SCN on the transfer time and throughput of the SV frames was measured. In addition, when using IEEE 1588 in the time synchronization process, it was verified that the clock offset remained unaffected irrespective of the use of VLANs or changes in the sampling frequency. The experimental results can serve as guidance for the actual planning and construction process of SCNs.

Improving of Knowledge, Attitudes, and Practices Towards Food Safety Among Caregivers in a Child Shelter in Ecuador to Provide Safe and Nutritious Meals

ObjectivesThe aim of this study was to improve knowledge, attitudes, and practices towards food safety among caregivers for providing safe and nutritious meals to the children living in the shelter through educational interventions. MethodsNine women in charge of the food preparation, three from the kitchen facility and six responsible for the formula preparation, were recruited in the study after signing informed consent. A specific knowledge, attitudes, and practices (KAP) survey was applied at the beginning of the study and after the educational intervention depending on the working area. The KAP survey for the three women responsible for the kitchen included 57 questions about handwashing, food preparation, food handling, food storage, and food preservation. The before and after the educational intervention results from these surveys were analyzed only with descriptive statistics due to the number of surveys applied. The KAP survey addressed the six women responsible for the formula preparation to infants included 38 questions about handwashing, formula bottle preparation, bottle sterilization, leftover formula storage, and handling of food for infants over 6 months. The responses collected before and after the educational intervention were analyzed by a Paired Student’s t-test considering significant a p-value < 0.1 using the RStudio software. The educational interventions were applied to the participants to address biased or misleading information and promote safe food practices. ResultsAfter the educational intervention of two months, the women responsible for the kitchen improved on average 29.67%, and those responsible for the formula preparation to infants had a significant improvement of 11.69% (p = 0.052). Due to the frame time available for the educational intervention being too short the participants mainly improved in knowledge. ConclusionsThe educational interventions were successful to improve biased or misleading information among the caregivers and help to ensure to provide safe and nutritious meals for the children living in the shelter. Additionally, specialized safety food and safety formula bottles preparation guides with a set of safe recipes were provided to the children’s shelter to help in the improvement of practices in the near future. Funding SourcesNone.

65‐2: A Light and Fast Branched Neural Network using Perceptual Optimization for High‐Quality Visual Restoration of UDC images

We propose a light and fast method to restore degraded images captured from under‐display cameras (UDCs) by modifying a branched deep neural network (BNUDC). The existing BNUDC is trained to minimize the per‐pixel difference of intensity between a ground truth and a restored image using L1 or L2 loss, and it has a large number of learnable parameters for achieving state‐of‐theart performance in terms of numerical distances such as PSNR and SSIM. Commercializing a deep‐learning‐based image restoration requires high perceptual image quality and real‐time inference speed. To this end, we downscale the original BNUDC to restore a 2k resolution image within 44ms which is the frame time for a 24Hz video, and train our network to reconstruct perceptually‐pleasing images using ‘perceptual optimization’. Our model has less than 1M learnable parameters, its inference time is less than 40ms, and it outperforms the original network in terms of perceptual image quality.

FMCPR: Flexible Multiparameter-Based Channel Prediction and Ranking for CR-Enabled Massive IoT

The cognitive radio-enabled <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$massive$ </tex-math></inline-formula> Internet of Things (CR- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$m$ </tex-math></inline-formula> IoT) is envisioned to shape the future of densely connected IoT devices in the sixth-generation networks to support the hyperconnected society. In conventional CR networks, secondary users (SUs) sense the whole block of spectrum to find idle channels, which is an energy-consuming, delay-inducing, and processing-intensive task. With the large scale of resource-constrained heterogeneous devices in CR- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$m$ </tex-math></inline-formula> IoT, the sensing process becomes a major hurdle for CR- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$m$ </tex-math></inline-formula> IoT devices to achieve efficient utilization of the limited device and network resources. Thus, a novel multiparameter-based flexible scheme is proposed for idle channel prediction and channel ranking, which considers priorities as well as heterogeneity of users. The scheme uses a probabilistic approach and employs multiple parameters simultaneously to evaluate the suitability of a channel before selecting it for transmission. In addition, valid channel obsolescence, a major problem inherent with channel prediction and ranking, is countered by the proposed scheme. The scheme is evaluated under the impact of variable primary and SUs’ arrivals and under multiple channel failures rates and variable sensing and frame time duration. The proposed scheme is also compared with its own modified version that disregards channel failures, and with the random channel selection approach followed by IEEE 802.22. The overall evaluation is conducted under realistic spectrum sensing. Simulation results show that for different parameter values, the proposed scheme improves the collision probability by 11%–55%, reduces sensing time and energy by 60% and 65%, respectively, and enhances throughput by 4%–70%, and spectrum utilization efficiency by 11%–40%.