Articoli di riviste: "MmW reliability"

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Baybayan, Jericho Y., e Michelle R. Lacia. "An Achievement Test in Mathematics in the Modern World Course: The Standardization Process". International Journal of Multidisciplinary: Applied Business and Education Research 5, n. 7 (23 luglio 2024): 2459–73. http://dx.doi.org/10.11594/ijmaber.05.07.08.

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This study aimed to construct and standardize an achievement test in Mathematics in the Modern World (MMW) course. Achievement test evaluates a student’s performance after a given period of instruction. Using the instrumentation research design, the data were gathered among 273 tertiary students of Notre Dame University enrolled during the second semester of Academic Year 2020-2021. Among these, 38 pilot tested and 213 tested the reliability of the instrument. This study further utilized the following: a 4-point Likert scale for the validation of the instrument, difficulty value and discrimination index formulas for the analysis of each item, and KR20 reliability for internal consistency. Furthermore, a test manual for the MMW achievement test was also established. The preliminary total number of Items before MMW teachers’ validation was 42 items covering the topics for the first 12 hours of the MMW Syllabus. These items were validated through Aiken’s Item Validity method which resulted in the acceptance of 42 items. After rigorous processes, it resulted in the acceptance of 34 items for the MMW achievement test. The instrument’s average validity is 0.935, and the reliability is 0.701 which means that this tool has high validity and acceptable reliability.

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Goldsmith, Chuck, John Maciel e John McKillop. "Demonstrating Reliability". IEEE Microwave Magazine 8, n. 99 (2007): x2. http://dx.doi.org/10.1109/mmw.2007.4383488.

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Magoba, Moses, e Mimonitu Opuwari. "Petrophysical interpretation and fluid substitution modelling of the upper shallow marine sandstone reservoirs in the Bredasdorp Basin, offshore South Africa". Journal of Petroleum Exploration and Production Technology 10, n. 2 (7 novembre 2019): 783–803. http://dx.doi.org/10.1007/s13202-019-00796-1.

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Abstract The fluid substitution method is used for predicting elastic properties of reservoir rocks and their dependence on pore fluid and porosity. This method makes it possible to predict changes in elastic response of a rock saturation with different fluids. This study focused on the Upper Shallow Marine sandstone reservoirs of five selected wells (MM1, MM2, MM3, MM4, and MM5) in the Bredasdorp Basin, offshore South Africa. The integration of petrophysics and rock physics (Gassmann fluid substitution) was applied to the upper shallow marine sandstone reservoirs for reservoir characterisation. The objective of the study was to calculate the volume of clay, porosity, water saturation, permeability, and hydrocarbon saturation, and the application of the Gassmann fluid substitution modelling to determine the effect of different pore fluids (brine, oil, and gas) on acoustic properties (compressional velocity, shear velocity, and density) using rock frame properties. The results showed average effective porosity ranging from 8.7% to 16.6%, indicating a fair to good reservoir quality. The average volume of clay, water saturation, and permeability values ranged from 8.6% to 22.3%, 18.9% to 41.6%, and 0.096–151.8 mD, respectively. The distribution of the petrophysical properties across the field was clearly defined with MM2 and MM3 revealing good porosity and MM1, MM4, and MM5 revealing fair porosity. Well MM4 revealed poor permeability, while MM3 revealed good permeability. The fluid substitution affected rock property significantly. The primary velocity, Vp, slightly decreased when brine was substituted with gas in wells MM1, MM2, MM3, and MM4. The shear velocity, Vs, remained unaffected in all the wells. This study demonstrated how integration of petrophysics and fluid substitution can help to understand the behaviour of rock properties in response to fluid saturation changes in the Bredasdorp Basin. The integration of these two disciplines increases the obtained results’ quality and reliability.

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Li, Yibing, Jie Chen, Fang Ye e Dandan Liu. "The Improvement of DS Evidence Theory and Its Application in IR/MMW Target Recognition". Journal of Sensors 2016 (2016): 1–15. http://dx.doi.org/10.1155/2016/1903792.

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ATR system has a broad application prospect in the military field, especially in the field of modern defense technology. When paradoxes are in existence in ATR system due to adverse battlefield environment, integration cannot be effectively and reliably carried out only by traditional DS evidence theory. In this paper, a modified DS evidence theory is presented and applied in IR/MMW target recognition system. The improvement of DS evidence theory is realized by three parts: the introduction of sensor priority and evidence credibility to realize the discount processing of evidences, the modification of DS combination rule to enhance the accuracy of synthesis results, and the compound decision-making rule. The application of the modified algorithm in IR/MMW system is designed to deal with paradoxes, improve the target recognition rate, and ensure the reliability of target recognition system. Experiments are given to illustrate that the introduction of the modified DS evidence theory in IR/MMW system is better able to realize satisfactory target recognition performance through multisensor information fusion than any single-mode system.

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Liu, Yunpeng, Kaifeng Liu, Jiang Mi e Mingbo Luo. "Distributed Multi-MMW Radar Fusion for Target Detection and Tracking in Highway Traffic Environment". Mathematical Problems in Engineering 2023 (15 aprile 2023): 1–11. http://dx.doi.org/10.1155/2023/5537122.

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High-resolution millimeter-wave (MMW) radar is viewed as a low-cost and highly reliable sensor compared to camera, lidar, etc., in moving scenarios and thus has been selected by highway stakeholders as an important roadside detector to detect the movement of traffic vehicles and monitor traffic flow in real time. However, the echo signal of MMW radar in complex highway environment contains not only the signal reflected by target but also spurious signals and other interference signals, which significantly affects the estimation of the target movement state. To solve this problem, an improved vehicle tracking method is designed to simultaneously estimate the polar angle and polar radius in coordinator of MMW radar. Moreover, considering the movement patterns of target vehicles in dynamic uncertain traffic situations, a set of state space models, such as CA, CV, and CT are combined to represent the vehicle movement. In addition, based on the enhanced detection performance of a single radar, the combination of multiple MMW radars’ information was performed to determine the sequential trajectory of the target vehicle on the continuous road sections; then, the historical trajectory of the target vehicle was correlated and fused. Real experiments in highway scenarios show that the method used in this study is effective in deriving the trajectory of the vehicle and improving the positioning accuracy and reliability when the vehicle performs heavy maneuvers.

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Hou, Wenkui, Wanyu Li e Pengyu Li. "Fault Diagnosis of the Autonomous Driving Perception System Based on Information Fusion". Sensors 23, n. 11 (26 maggio 2023): 5110. http://dx.doi.org/10.3390/s23115110.

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The reliability of autonomous driving sensing systems impacts the overall safety of the driving system. However, perception system fault diagnosis is currently a weak area of research, with limited attention and solutions. In this paper, we present an information-fusion-based fault-diagnosis method for autonomous driving perception systems. To begin, we built an autonomous driving simulation scenario using PreScan software, which collects information from a single millimeter wave (MMW) radar and a single camera sensor. The photos are then identified and labeled via the convolutional neural network (CNN). Then, we fused the sensory inputs from a single MMW radar sensor and a single camera sensor in space and time and mapped the MMW radar points onto the camera image to obtain the region of interest (ROI). Lastly, we developed a method to use information from a single MMW radar to aid in diagnosing defects in a single camera sensor. As the simulation results show, for missing row/column pixel failure, the deviation typically falls between 34.11% and 99.84%, with a response time of 0.02 s to 1.6 s; for pixel shift faults, the deviation range is between 0.32% and 9.92%, with a response time of 0 s to 0.16 s; for target color loss, faults have a deviation range of 0.26% to 2.88% and a response time of 0 s to 0.05 s. These results prove the technology is effective in detecting sensor faults and issuing real-time fault alerts, providing a basis for designing and developing simpler and more user-friendly autonomous driving systems. Furthermore, this method illustrates the principles and methods of information fusion between camera and MMW radar sensors, establishing the foundation for creating more complicated autonomous driving systems.

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da Silva, Claudio Bastos, Rafael da Silva Ferraz e Horacio Tertuliano Santos. "An Analysis of the Fading Channel Valid for Frequencies Up to the mmW Range". Journal of Computational and Theoretical Nanoscience 18, n. 6 (1 giugno 2021): 1754–58. http://dx.doi.org/10.1166/jctn.2021.9727.

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The fading phenomenon in mobile communications is mainly a stochastic process and plays an essential role in the reliability and stability of the systems. The frequency bands currently in use it is reasonably well characterized and described. With the use of mmW, only experimental, theoretical models are being proposed; there is no unanimity regarding a model that effectively contemplates the phenomenon in this spectrum range. Some studies suggest the traditional models applied to the frequencies in use; Rician and Rayleigh are the main ones. This study aims to advance and compare, with accepted models, a broader statistical model that overcomes the limitations of the current models. It will be analyzed and compared a model using the Nakagami-m distribution covering a greater range of possibilities, given the low spreading capacity of mmW and the need for links almost always LOS situation in which the Rician model fails.

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da Silva, Claudio Bastos, Rafael da Silva Ferraz e Horacio Tertuliano Santos. "An Analysis of the Fading Channel Valid for Frequencies Up to the mmW Range". Journal of Computational and Theoretical Nanoscience 18, n. 6 (1 giugno 2021): 1754–58. http://dx.doi.org/10.1166/jctn.2021.9727.

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The fading phenomenon in mobile communications is mainly a stochastic process and plays an essential role in the reliability and stability of the systems. The frequency bands currently in use it is reasonably well characterized and described. With the use of mmW, only experimental, theoretical models are being proposed; there is no unanimity regarding a model that effectively contemplates the phenomenon in this spectrum range. Some studies suggest the traditional models applied to the frequencies in use; Rician and Rayleigh are the main ones. This study aims to advance and compare, with accepted models, a broader statistical model that overcomes the limitations of the current models. It will be analyzed and compared a model using the Nakagami-m distribution covering a greater range of possibilities, given the low spreading capacity of mmW and the need for links almost always LOS situation in which the Rician model fails.

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Jing, Rui, Zhenqi Jiang e Xiaoying Tang. "Advances in Millimeter-Wave Treatment and Its Biological Effects Development". International Journal of Molecular Sciences 25, n. 16 (8 agosto 2024): 8638. http://dx.doi.org/10.3390/ijms25168638.

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This comprehensive review critically examines the current state of research on the biological effects of millimeter-wave (MMW) therapy and its potential implications for disease treatment. By investigating both the thermal and non-thermal impacts of MMWs, we elucidate cellular-level alterations, including changes in ion channels and signaling pathways. Our analysis encompasses MMW’s therapeutic prospects in oncology, such as inducing apoptosis, managing pain, and modulating immunity through cytokine regulation and immune cell activation. By employing a rigorous methodology involving an extensive database search and stringent inclusion criteria, we emphasize the need for standardized protocols to enhance the reliability of future research. Although MMWs exhibit promising therapeutic potential, our findings highlight the urgent need for further elucidation of non-thermal mechanisms and rigorous safety assessments, considering the intricate nature of MMW interactions and inconsistent study outcomes. This review underscores the importance of focused research on the biological mechanisms of MMWs and the identification of optimal frequencies to fully harness their therapeutic capabilities. However, we acknowledge the challenges of variable study quality and the necessity for advanced quality control measures to ensure the reproducibility and comparability of future investigations. In conclusion, while MMW therapy holds promise as a novel therapeutic modality, further research is imperative to unravel its complex biological effects, establish safety profiles, and optimize treatment protocols before widespread clinical application.

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Jin, Tianshi, Chenxi Zhang, Yikang Zhang, Mingliang Yang e Weiping Ding. "A Hybrid Fault Diagnosis Method for Autonomous Driving Sensing Systems Based on Information Complexity". Electronics 13, n. 2 (14 gennaio 2024): 354. http://dx.doi.org/10.3390/electronics13020354.

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In the context of autonomous driving, sensing systems play a crucial role, and their accuracy and reliability can significantly impact the overall safety of autonomous vehicles. Despite this, fault diagnosis for sensing systems has not received widespread attention, and existing research has limitations. This paper focuses on the unique characteristics of autonomous driving sensing systems and proposes a fault diagnosis method that combines hardware redundancy and analytical redundancy. Firstly, to ensure the authenticity of the study, we define 12 common real-world faults and inject them into the nuScenes dataset, creating an extended dataset. Then, employing heterogeneous hardware redundancy, we fuse MMW radar, LiDAR, and camera data, projecting them into pixel space. We utilize the “ground truth” obtained from the MMW radar to detect faults on the LiDAR and camera data. Finally, we use multidimensional temporal entropy to assess the information complexity fluctuations of LiDAR and the camera during faults. Simultaneously, we construct a CNN-based time-series data multi-classification model to identify fault types. Through experiments, our proposed method achieves 95.33% accuracy in detecting faults and 82.89% accuracy in fault diagnosis on real vehicles. The average response times for fault detection and diagnosis are 0.87 s and 1.36 s, respectively. The results demonstrate that the proposed method can effectively detect and diagnose faults in sensing systems and respond rapidly, providing enhanced reliability for autonomous driving systems.

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EL BOUAYADI, Ossama, Yann LAMY, Laurent DUSSOPT e Brigitte SOULIER. "A New Approach for Reliable and Compact 3D Integration of mmW Transceivers on Silicon Using High-Impedance Surface Antennas". International Symposium on Microelectronics 2014, n. 1 (1 ottobre 2014): 000810–15. http://dx.doi.org/10.4071/isom-thp21.

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3D integration of heterogeneous modules including RF and millimeter-wave (mmW) functionalities is opening new challenges for packaging developers to conciliate between electrical performance, thermal behavior and mechanical reliability using cost-effective technologies. This paper deals with innovative integrated antenna solutions within the particular context of 3D heterogeneous integration on silicon interposer using a disruptive design approach. Novel integration schemes of antennas using a high-impedance surface (HIS) reflector are presented. Then, the design steps of a 60-GHz folded dipole antenna for short-range communications are detailed. Simulation and measurement results show promising performances in terms of gain and radiation efficiency. Process and fabrication issues are addressed with specific Back-End processing developments and an experimental validation is proposed.

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Ogura, Nobuo, Siddharth Ravichandran, Tailong Shi, Atom Watanabe, Shuhei Yamada, Mohanalingam Kathaperumal e Rao Tummala. "First Demonstration of Ultra-Thin Glass Panel Embedded (GPE) Package with Sheet Type Epoxy Molding Compound for 5G/mm-wave Applications". International Symposium on Microelectronics 2019, n. 1 (1 ottobre 2019): 000202–7. http://dx.doi.org/10.4071/2380-4505-2019.1.000202.

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Abstract With the number of connected-devices increasing tremendously, communication data rates are projected to be at least 10–100X in the 5G/mm-wave (MMW) technology - much higher than the existing 4G LTE connections.[1], [2] To catch up with the trend, novel packaging technology in the MMW frequency range is required, which will address fundamental MMW technical challenges such as high dielectric loss, degradation of quality factors in passives, increased parasitic, dramatically-enhanced electromagnetic interference, and the reduced radiation efficiency of antenna arrays. State-of-the-art approaches being pursued include organic-core substrates that have a low dielectric constant (Dk) and low dissipation factor (Df) such as fluorine based or liquid-crystal polymer (LCP) substrates in order to achieve enhanced antenna performance and low signal dissipations. These organic-based substrate technologies, however, can neither miniaturize packages nor handle precision signal routings that enable high density packages. To address these challenges, attention is focused on Fan-Out Wafer Level Package (FOWLP) technologies, like eWLB, InFO, and SWIFT, where integrated circuits (ICs) are embedded in epoxy molding compound. [3]–[6] Recently, glass-panel embedding (GPE) technology is emerging as an ideal packaging methodology that enables superior performance along with small form factor, ultra-low-loss, high density, ultra-short interconnects, and low cost. [7] These benefits stem from the advantages of using glass which has excellent properties such as ultra-smooth surface for precision redistribution layer (RDL), exceptional dimensional stability for panel-scalability and tailorability of CTE that allow direct board-attach for improved system performance. In addition, utilizing the epoxy molding compounds as encapsulation material allows the GPE package to be thinner and more robust package with small farm factor. Molding of glass cavity panels also helps with the handling of ultra-thin glass which is seen as a bottleneck towards glass based packaging solutions in production. These facilitates enhanced throughput by allowing more cavity cut outs (more coupons) per panel. This paper presents the first demonstration of ultra-thin GPE with sheet type epoxy molding compound (SMC) for 5G/mm-wave applications. First part of this paper discusses the process-flow used in glass-panel embedding with laminated SMC, including chip placement in glass cavities, lamination of SMC, and the reliability of the package architecture. This paper reports on such a demonstration in 60 μm glass substrates with 40 μm thickness SMC. The second part of this paper focuses on low-loss interconnects for 5G/mm-wave applications and presents the process development of signal routings such as transmission lines and microvias in RDLs as well as through-package vias (TPVs) with via-in-via process. The results suggest that the ultra-thin GPE architecture is a promising packaging technology solution for a variety of applications including high-frequency communications and high-performance computing.

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Hesham Emara, Sherif K. El Dyasti, Hussein Hamed Ghouz e Mohamed Fathy Abo Sree. "Design of a Compact Dual-Frequency Microstrip Antenna using DGS Structure for Millimeter-Wave Applications". Journal of Advanced Research in Applied Sciences and Engineering Technology 28, n. 3 (30 novembre 2022): 221–34. http://dx.doi.org/10.37934/araset.28.3.221234.

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In this paper, a Millimeter-wave (MMW) antenna has been proposed for a current and future wireless application. The proposed model has two resonances at 30.5 GHz and 52.4 GHz. The proposed model has been designed and optimized using a commercial electromagnetic simulator (CST-Studio) and focused on attaining a return loss rate that is lower than -10 dB. The proposed MMW models are built on a small thick Rogers Substrate (RT-5880) with h = 0.508 mm for the thickness, relative permittivity of εr = 2.2, and tanδ = 0.0009 for the loss tangent, while the substrate has a width w_s equal to 6 mm and a length l_s equal to 6 mm. The design process of the model came at three steps, the first step after mathematical calculations has an output of model which has feeding port of 50 ohm with a feedline base length l_b of 0.5 mm and a feedline length l_f of 3 mm, the second step was by using the tapering techniques for enhancing matched impedance after initial calculations to have a length of tapering l_t equal to 1.8 mm, then finally extracting four corner slots to the patch for creating the final proposed model. The previous design process is to assure reliability, mobility, and high efficiency for the proposed antenna. The advantages of this model are the small size, low profile, low fabrication cost, and straightforward design structure. The proposed design can be employed for a variety of Millimeter-wave applications like wireless personal area network (WPAN) and 5G application in some countries like Colombia and Mexico. The proposed model has a moderate gain of 3 dBi to 7 dBi at resonance frequencies of 30.5 GHz and 52.4 GHz, which is one of the unique characteristics of the proposed antenna. The impedance bandwidth is between 28.7 Ghz and 32.6 GHz, which is equal 3.9 GHz, and 49.7 GHz to 56.2 GHz, which is equal to 6.5 GHz respectively for the proposed model, and satisfying efficiency of about 75% and 87% as calculated by CST -Studio, and a VSWR is equal to 1, All of these positive results are more than enough to satisfy the needs of millimeter-wave wireless applications.

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Favier, Gérard, e Danilo Sousa Rocha. "Overview of Tensor-Based Cooperative MIMO Communication Systems—Part 1: Tensor Modeling". Entropy 25, n. 8 (8 agosto 2023): 1181. http://dx.doi.org/10.3390/e25081181.

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Due to increasingly strong and varied performance requirements, cooperative wireless communication systems today occupy a prominent place in both academic research and industrial development. The technological and economic challenges for future sixth-generation (6G) wireless systems are considerable, with the objectives of improving coverage, data rate, latency, reliability, mobile connectivity and energy efficiency. Over the past decade, new technologies have emerged, such as massive multiple-input multiple-output (MIMO) relay systems, intelligent reflecting surfaces (IRS), unmanned aerial vehicular (UAV)-assisted communications, dual-polarized (DP) antenna arrays, three dimensional (3D) polarized channel modeling, and millimeter-wave (mmW) communication. The objective of this paper is to provide an overview of tensor-based MIMO cooperative communication systems. Indeed, during the last two decades, tensors have been the subject of many applications in signal processing, especially for digital communications, and more broadly for big data processing. After a brief reminder of basic tensor operations and decompositions, we present the main characteristics allowing to classify cooperative systems, illustrated by means of different architectures. A review of main codings used for cooperative systems is provided before a didactic and comprehensive presentation of two-hop systems, highlighting different tensor models. In a companion paper currently in preparation, we will show how these tensor models can be exploited to develop semi-blind receivers to jointly estimate transmitted information symbols and communication channels.

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Dowrick, David J., Graham T. Hancox, Nick D. Perrin e Grant D. Dellow. "The Modified Mercalli intensity scale". Bulletin of the New Zealand Society for Earthquake Engineering 41, n. 3 (30 settembre 2008): 193–205. http://dx.doi.org/10.5459/bnzsee.41.3.193-205.

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Recent studies of the effects and Modified Mercalli (MM) intensities of New Zealand earthquakes have established criteria that will improve the reliability of intensities assigned using a number of effects, particularly the incidence of chimney damage and a wide range of environmental phenomena. The proportions of brittle chimneys which were damaged at intensities MM5–MM10 have been counted from the very detailed database of the 1968 Mw 7.2 Inangahua earthquake, and are shown to relate well to the proportions of chimneys which fell in 10 other earthquakes. Criteria based on environmental effects at intensities MM5-MM10 have been extended based on detailed studies of 22 earthquakes. These criteria have been adopted in an international intensity scale for environmental effects. It was also found that the stopping of clocks should be a criterion for MM3, not MM5, and similarly the disturbance of liquids should be used at the threshold intensity of MM3 rather than MM4, as in the present MM intensity scale. With the probable saturation of intensity at MM10, the criteria for MM12 have been omitted.

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Jin, Cao, Yan Huang, Mansoor Nasim, Yihe Yang e Lili Lee. "Gastrointestinal Stromal Tumors Risk Stratification Utilizing Phospho-Histone H3 Evaluated by Manual Counting and Computer-Assisted Image Analysis". International Journal of Surgical Pathology 27, n. 7 (30 maggio 2019): 706–12. http://dx.doi.org/10.1177/1066896919851866.

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Background. Risk of progressive disease of gastrointestinal stromal tumors (GISTs) relies on mitotic index, size, and location of the tumor. However, manual mitotic counting on hematoxylin and eosin–stained slides (MMC-HE) is inefficient with low reproducibility. Manual count of phospho-histone H3 (MC-PHH3)-positive cells on immunohistochemical stained slides has been shown to have comparable reliability with MMC-HE. This study aims to confirm the reliability of MC-PHH3 in GISTs compared with MMC-HE and then to further compare MC-PHH3 with computer-assisted image analysis of PHH3-positive cells (Comp-PHH3). Methods. The study included 119 patients with GISTs. PHH3 stains were performed. MC-PHH3 was assessed as counts/5 mm2 high-power fields. Whole slide images were captured and the tumor area with greatest mitotic activity was manually identified. The PHH3-positive cells were automatically counted in 0.5 mm2 using Ventana Virtuoso software. Results. MMC-HE ranged from 0 to 157/5 mm2. MC-PHH3 ranged from 0 to 35.6/5 mm2. Comp-PHH3 ranged from 0 to 66/0.5 mm2. Interclass correlation coefficient (ICC) indicates good agreement between the 3 pathologists for MC-PHH3 (ICC = 0.74, P = .42). There is a strong correlation between MMC-HE and MC-PHH3. The Spearman correlation coefficient was 0.63 ( P < .0001). Lin’s concordance further indicated a moderate diagnostic agreement between MC-PHH3 and Comp-PHH3. Conclusion. MC-PHH3 is proposed as a superior alternative to MMC-HE with potential application in GIST reporting and prognostication. Furthermore, Comp-PHH3 may be a valid alternative to MC-PHH3.

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Albright, A. Leland, Susan S. Ferson e Humphrey Okechi. "Cerebrospinal fluid white blood cell counts in infants with myelomeningoceles". Journal of Neurosurgery: Pediatrics 13, n. 2 (febbraio 2014): 189–91. http://dx.doi.org/10.3171/2013.11.peds13196.

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Object The authors undertook this study to determine white blood cell (WBC) counts in CSF obtained from lateral ventricles and myelomeningoceles (MMCs) in infants in a developing country at the time of their initial presentation for medical evaluation. Methods CSF was aspirated from the lateral ventricles and from MMC sacs of 100 consecutive infants at Kijabe Hospital, Kijabe, Kenya. Peripheral blood WBC counts and CSF WBC counts were determined in the laboratory. CSF with WBC counts of 5 cells/mm3 or greater was cultured. Results The mean WBC count in ventricular CSF was 16 cells/mm3, with a median and mode of 0 cells/mm3. The mean WBC count of CSF in MMC sacs was 141 cells/mm3 (median 15 cells/mm3). No child had both a positive culture from ventricular CSF and a negative culture from MMC CSF. There was no correlation between age at presentation and WBC counts in the MMCs. Infants younger than 8 days old were as likely to have high WBC counts in CSF from their MMC sacs as were older children; 7 of 12 infants with 500 WBCs or more in CSF from their MMCs were younger than 8 days old. Only 5 of 58 CSF specimens from MMC sacs with 5 or more WBCs/mm3 had positive bacterial cultures, which may be a reflection of CSF specimen processing rather than of true culture negativity. Conclusions CSF from ventricular fluid of infants presenting with MMCs infrequently has high WBC counts, so infrequently that it does not need to be evaluated routinely. CSF in MMC sacs often has high WBC counts that suggest the presence of bacterial infection. In developing countries where culture reliability is questionable, intravenous administration of antibiotics before MMC closure for infants with high MMC WBC counts may diminish postoperative meningitis/ventriculitis.

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Bunel, Catherine, e Franck Murray. "Ultra High 3D Capacitors Values with High Volume Efficiency and Outstanding Stability". Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2012, DPC (1 gennaio 2012): 001163–91. http://dx.doi.org/10.4071/2012dpc-tp41.

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IPDIA's primary effort is to develop innovative 3D technologies to integrate Passive Devices .One of their key technology drivers is the trench high-density capacitor. After introducing the 250nF/mm2 in mass production, it's now the turn to launch outstanding performances with a new worldwide record of 550nF/mm2. With the advanced packaging solutions using very thin dies stacking ,combining a high level of capacitance integration and high volumetric efficiency, this achievement will enable to extend the range of high reliability Silicon Capacitor values up to 10 μF in a package size 3.4mm*2.4mm*1.4mm and even smaller . This paper will provide the details to prove that the former ambitious target of 2 μF/mm3 is now close to reality.

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Fan, X. F., D. Y. Qiu, B. Zhang, Y. F. Chen, R. H. Huang, W. Y. Cao, S. K. Xu, C. Fu, H. Rao e L. C. Li. "Mode identification for reliability improvement of MMC". Microelectronics Reliability 114 (novembre 2020): 113851. http://dx.doi.org/10.1016/j.microrel.2020.113851.

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Whitney, JoAnne. "Reliability coefficients". Journal of WOCN 27, n. 4 (luglio 2000): 0238–39. http://dx.doi.org/10.1067/mjw.2000.107483.

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Goldsmith, Chuck, John Maciel e John Mckillop. "Demonstrating Reliability". IEEE Microwave Magazine 8, n. 6 (dicembre 2007): 56–60. http://dx.doi.org/10.1109/mmm.2007.902197.

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Goldsmith, Chuck, John Maciel e John Mckillop. "Demonstrating Reliability". IEEE Microwave Magazine 8, n. 6 (dicembre 2007): 56–60. http://dx.doi.org/10.1109/mmm.2007.907197.

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Wang, Shuaiqing, Shuai Chen, Yongjie Hu, Xuebin Hu, Qiuling Hu, Gengsheng Guan e Xiaofeng Zhou. "Modeling and Reliability Constraint Analysis of MMC Valve". Journal of Physics: Conference Series 2656, n. 1 (1 dicembre 2023): 012025. http://dx.doi.org/10.1088/1742-6596/2656/1/012025.

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Abstract The VSC-converter valve is the core equipment of the VSC-HVDC transmission system, and its reliability directly affects the availability of the VSC-HVDC system. The reliability model of the existing VSC-converter valve mainly considers the relationship between different redundancy and the reliability of the VSC-converter valve. This paper first analyzes the impact of the failure of key components of the VSC-converter valve. According to the different effects, the arm reliability model of the VSC-converter valve is established, and finally, the comprehensive reliability model of the VSC-converter valve is established. Then, based on the model of the VSC-converter valve, the reliability constraints of the VSC-converter valve that meet the engineering requirements are finally derived. An example is given to verify the correctness of the classification reliability evaluation. Finally, according to the reliability model proposed in this paper, the design recommendations for a highly reliable VSC converter valve are given.

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Wang, Biyang, Xifan Wang, Zhaohong Bie, Paul D. Judge, Xiuli Wang e T. C. Green. "Reliability Model of MMC Considering Periodic Preventive Maintenance". IEEE Transactions on Power Delivery 32, n. 3 (giugno 2017): 1535–44. http://dx.doi.org/10.1109/tpwrd.2016.2602888.

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Zheng, Tao, Meng Huang, Lingyi Zhu e Xiaoming Zha. "Reliability evaluation of MMC system considering working conditions". Journal of Engineering 2019, n. 16 (1 marzo 2019): 1877–81. http://dx.doi.org/10.1049/joe.2018.8891.

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Trew, Robert, Daniel Green e Jeffrey Shealy. "AlGaN/GaN HFET reliability". IEEE Microwave Magazine 10, n. 4 (giugno 2009): 116–27. http://dx.doi.org/10.1109/mmm.2009.932286.

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Lu, Xiaojian, Zi’an Zeng, Xichao Lv, Xusong Luo, Gongliao Zhang e Youping Fan. "Hybrid MMC Redundancy Configuration Calculation Method Based on Heuristic Algorithm". Journal of Physics: Conference Series 2173, n. 1 (1 gennaio 2022): 012077. http://dx.doi.org/10.1088/1742-6596/2173/1/012077.

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Abstract Most of the existing redundant configuration methods of modular level converters (MMC) only consider the reliability of the MMC, and rarely consider the utilization of insulated gate bipolar transistors (IGBT). A heuristic algorithm-based calculation method for hybrid MMC redundancy configuration is proposed in order to better meet the engineering practicality. Firstly, the topology of the hybrid MMC is introduced, and the correlation between submodules is introduced into the calculation of its reliability. Secondly, the index of IGBT utilization is proposed to judge the economic advantage. The effects of correlation and service life on the reliability of the hybrid MMC and the IGBT utilization are analyzed. Then, heuristic factors are constructed with reliability and IGBT utilization, and the optimal redundancy configuration scheme of hybrid MMC is obtained by heuristic algorithm. Finally, based on the parameters of Kunliulong multi-terminal hybrid DC transmission project, the calculation is verified in Matlab and compared with the results of the difference method to illustrate the feasibility and superiority of the proposed redundancy configuration calculation method.

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Wang, Longjun, Guoping Ou, Zhenwei Zhou, Gang Wang, Pengfei Yu e Zheng Zhang. "Cumulative Fatigue Damage Balancing for Modular Multilevel Converter". Energies 13, n. 18 (7 settembre 2020): 4640. http://dx.doi.org/10.3390/en13184640.

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With many advantages, modular multilevel convert (MMC) has been extensively used in high and medium voltage power transmission projects. The thermal performance and reliability of components in MMC are key issues in system operation. However, in the current research on the reliability of MMC components, there are few methods to improve service lifetime expectancy of the components. This paper proposes a balance control algorithm, based on the cumulative fatigue damage of components, feedback to the control terminal for allocating the sub-module (SM) operating state and generating trigger pulses. Finally, the effectiveness of the proposed algorithm is verified and discussed in case studies. It is found that this algorithm is able to improve the aging degree of components in the meanwhile, the improvement in MMC reliability comes at the cost of slightly increasing capacitor voltage fluctuations and total harmonic distortion (THD). Due to the limitation of capacitor thermal performance, SM capacitor banks become a weak link in MMC reliability.

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Pastore, Marco R., Alberto Grotto, Francesca Vezzoni, Andrea Gaggino, Serena Milan, Stefano Gouigoux, Pier Luigi Guerin, Alex L. Vinguerra, Gabriella Cirigliano e Daniele Tognetto. "Reproducibility and Reliability of Spectralis II OCT Angiography Vascular Measurements". Diagnostics 12, n. 8 (7 agosto 2022): 1908. http://dx.doi.org/10.3390/diagnostics12081908.

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Purpose: to investigate the reproducibility and reliability of OCT-A vascular measurements using Heidelberg Spectralis II OCT-A. Methods: a prospective study involving a single eye of patients aged 18 or older with no ocular disease. In order to investigate the reliability of the first and second OCT-A scans, the coefficient of variation of the foveal avascular zone (FAZ) and the vessel density (VD) in the superficial (SCP), intermediate (ICP) and deep capillary plexus (DCP) were calculated. Results: A total of 75 eyes were included in the study. The mean FAZ in the first and second scan was 0.36 × 0.13 mm2 and 0.37 × 0.12 mm2, respectively, in the SCP, 0.23 × 0.10 mm2 and 0.23 × 0.09 mm2 in the ICP, and 0.42 × 0.11 mm2 and 0.43 × 0.12 mm2 in the DCP. The overall VD was 36.05 × 9.01 and 35.33 × 9.92 at the first and second scan, respectively, in the SCP, 21.87 × 5.00 and 21.32 × 5.56 in the ICP, and 23.84 × 6.53 and 23.20 × 6.83 in the DCP. No statistically significant differences in FAZ measurements and VD in all sectors of each capillary plexus were observed between the first and second scan (p > 0.05). Conclusion: our study demonstrated the good reproducibility and reliability of OCT-A vascular measurements in the analysis of the FAZ and the quantification of VD in each capillary plexus of the retina.

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Lee, Byung-Heon, Tae-Ha Son e Jong-Ho Park. "P-43 A reliability study of 500 MW turbine control hydraulic pumps". Abstracts of ATEM : International Conference on Advanced Technology in Experimental Mechanics : Asian Conference on Experimental Mechanics 2007.6 (2007): _P—43–1_—_P—43–6_. http://dx.doi.org/10.1299/jsmeatem.2007.6._p-43-1_.

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VASIU, Teodor, e Adina BUDIUL BERGHIAN. "Determining the Reliability of Clincher Coolers". Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science 41, n. 3 (15 settembre 2018): 51–56. http://dx.doi.org/10.35219/mms.2018.3.08.

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Smith, P. "Gulliver's Travels, assessment, reliability, and validity". Journal of WOCN 28, n. 6 (novembre 2001): 261–62. http://dx.doi.org/10.1067/mjw.2001.119353.

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Hando, Ben R., W. Casan Scott, Jacob F. Bryant, Juste N. Tchandja, Ryan M. Scott e Siddhartha S. Angadi. "Association Between Markerless Motion Capture Screenings and Musculoskeletal Injury Risk for Military Trainees: A Large Cohort and Reliability Study". Orthopaedic Journal of Sports Medicine 9, n. 10 (1 ottobre 2021): 232596712110416. http://dx.doi.org/10.1177/23259671211041656.

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Background: Markerless motion capture (MMC) systems used to screen for musculoskeletal injury (MSKI) risk have become popular in military and collegiate athletic settings. However, little is known regarding the test-retest reliability or, more importantly, the ability of these systems to accurately identify individuals at risk for MSKI. Purpose: To determine the association between scores from a proprietary MMC movement screen test and the likelihood of suffering a subsequent MSKI and establish the test-retest reliability of the MMC system used. Study Design: Cohort study; Level of evidence, 3. Methods: Trainees for the Air Force Special Warfare program underwent MMC screenings immediately before entering the 8-week training course. MSKI data were extracted from a database for the surveillance period for each trainee. Logistic regression analyses were performed to identify associations between baseline MMC scores and the likelihood of suffering any MSKI or, specifically, a lower extremity MSKI. The test-retest portion of the study collected MMC scores from 10 separate participants performing 4 trials of the standard test procedures. Reliability was assessed using intraclass correlation coefficients by a single rater. Results: Overall, 1570 trainees, of whom 800 (51%) suffered an MSKI, were included in the analysis. MMC scores poorly predicted the likelihood of any or a lower extremity MSKI (odds ratio, 1.01-1.02). Further, receiver operating characteristic curve analyses demonstrated poor sensitivity and specificity for prediction of MSKI with MMC scores (area under the curve = 0.53). Finally, intraclass correlation coefficients from the test-retest analysis of MMC scores ranged from 0.157 to 0.602. Conclusion: This MMC system displayed poor to moderate test-retest reliability and did not demonstrate the ability to discriminate between individuals who were and were not likely to suffer an MSKI.

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Lau, John H., Cheng-Ta Ko, Chia-Yu Peng, Kai-Ming Yang, Tim Xia, Puru Bruce Lin, Jean-Jou Chen et al. "Chip-Last (RDL-First) Fan-Out Panel-Level Packaging (FOPLP) for Heterogeneous Integration". Journal of Microelectronics and Electronic Packaging 17, n. 3 (1 luglio 2020): 89–98. http://dx.doi.org/10.4071/imaps.1137828.

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Abstract In this investigation, the chip-last, redistribution-layer (RDL)–first, fan-out panel-level packaging (FOPLP) for heterogeneous integration is studied. Emphasis is placed on the materials, process, fabrication, and reliability of a heterogeneous integration of one large chip (10 × 10 mm2) and two small chips (7 × 5 mm2) by an FOPLP method on a 20 × 20-mm2 RDL-first substrate fabricated on a 515 × 510 mm2 temporary glass panel. Reliability test such as the drop test of the heterogeneous integration package on a printed circuit board (PCB) is performed, and test results including failure analysis are presented. Some recommendations are also provided.

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Unamba, K. U. "Probabilistic Assessment of Sandwiched Concrete Slabs in Deflection". International Journal for Research in Applied Science and Engineering Technology 9, n. 9 (30 settembre 2021): 2052–58. http://dx.doi.org/10.22214/ijraset.2021.38248.

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Abstract: This study presents a probabilistic evaluation of concrete sand-witched hollow core slabs in accordance with the design requirements of BS8110 (1985; 1997) and Eurocode 2 (2008). The First Order Reliability Method (FORM) was used in computing the probability of failure. For the deflection failure, the effect of varying the load ratio and the breadth of slab on the reliability analysis were carried out at the following values of concrete strengths ݂ܿu: 25N/mm2 , 30 N/mm2 , 40 N/mm2 , 50 N/mm2 . The results indicate that deflection characteristics of the slab are directly affected by the concrete strength, loadings, breadth of slab selected. Thus, the deflection of the slab increases with increases in loading, hollow core, breadth of slab and decrease in concrete strength. This shows that the safety index of reinforced sandwiched concrete slab in deflection generally decreases as the load ratio and breadth of slab increase for each combination of concrete strength. Keywords: Probabilistic Analysis, Sandwiched Concrete, Reliability Analysis, Stochastic Model, FORM

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Bliss, D. "Reliability of a stool consistency classification system". Journal of WOCN 28, n. 6 (novembre 2001): 305–13. http://dx.doi.org/10.1067/mjw.2001.119013.

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Xu, Jianzhong, Penghao Zhao e Chengyong Zhao. "Reliability Analysis and Redundancy Configuration of MMC With Hybrid Submodule Topologies". IEEE Transactions on Power Electronics 31, n. 4 (aprile 2016): 2720–29. http://dx.doi.org/10.1109/tpel.2015.2444877.

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Alharbi, Mohammed, Semih Isik e Subhashish Bhattacharya. "Submodule Fault-Tolerant Strategy for Modular Multilevel Converter with Scalable Control Structure". Sustainability 14, n. 24 (8 dicembre 2022): 16445. http://dx.doi.org/10.3390/su142416445.

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Abstract (sommario):

Modular Multilevel Converter (MMC) topology is considered a good candidate for high-voltage applications. One of the reasons is that an MMC can quickly generate a higher voltage with an excellent sine wave with the series connection of many power blocks, called Sub-Modules (SMs). In such applications, the control system of an MMC can be challenging, and the possibility of an SM failure increases. As a result, the reliability and availability of the application reduce over time. To reduce the effects of SM failure, an MMC is usually equipped with Redundant SMs (RSMs). The RSMs are added into MMC arms as regular SMs to increase the application’s reliability and reduce downtime. This paper proposes a unique decentralized SM fault-tolerant control model for RSMs to participate in any SM sets. In an MMC arm, a dedicated controller is assigned to RSMs, while the group of SMs has their local controllers. The controller of the RSMs continually monitors the voltage of all the SM sets in the arm. If there is any failure, the controller of the RSMs activates a requested number of SMs to help local controllers to generate the desired voltage level. The proposed control system significantly reduces local controllers’ computational and communication requirements compared to conventional redundant controllers. The proposed control system is based on a distributed structure, so it does not limit hardware flexibility, such as the scalability and modularity of an MMC system. Besides, the separate controller for the RSMs significantly helps increase the reliability of an MMC application.

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Qin, Boyu, Wansong Liu, Ruowei Zhang, Jialing Liu e Hengyi Li. "Review on Short-circuit Current Analysis and Suppression Techniques for MMC-HVDC Transmission Systems". Applied Sciences 10, n. 19 (27 settembre 2020): 6769. http://dx.doi.org/10.3390/app10196769.

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The modular multilevel converter (MMC) has been widely adopted in high voltage direct current (HVDC) transmission systems due to its significant advantages. MMC-HVDC is developing towards multi-terminal direct current (MTDC) power grid for reliability enhancement. However, there exist a huge amplitude and a steep rise in fault current due to the low impedances of DC lines and MMCs, which threaten the security and reliability of the DC power grids. It is necessary to restrain the DC short circuit current in order to ensure the safe and stable operation of DC power grids. This paper gives a comprehensive review and evaluation of the proposed DC short-circuit current analysis and suppression techniques used in MMC-based MTDC power girds, in terms of MMC modeling, short circuit calculation, and suppression method. In addition, future trends of countermeasures to short circuit current in MMC-based MTDC power grids are also discussed.

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Rumiński, Jacek. "Reliability of Pulse Measurements in Videoplethysmography". Metrology and Measurement Systems 23, n. 3 (1 settembre 2016): 359–71. http://dx.doi.org/10.1515/mms-2016-0040.

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Abstract Reliable, remote pulse rate measurement is potentially very important for medical diagnostics and screening. In this paper the Videoplethysmography was analyzed especially to verify the possible use of signals obtained for the YUV color model in order to estimate the pulse rate, to examine what is the best pulse estimation method for short video sequences and finally, to analyze how potential PPG-signals can be distinguished from other (e.g. background) signals. The presented methods were verified using data collected from 60 volunteers.

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Nguyen, Tung, Hugo De Clerck, Michael Wilson e Brent Golden. "Effect of Class III bone anchor treatment on airway". Angle Orthodontist 85, n. 4 (23 settembre 2014): 591–96. http://dx.doi.org/10.2319/041614-282.1.

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ABSTRACT Objectives: To compare airway volumes and minimum cross-section area changes of Class III patients treated with bone-anchored maxillary protraction (BAMP) versus untreated Class III controls. Materials and Methods: Twenty-eight consecutive skeletal Class III patients between the ages of 10 and 14 years (mean age, 11.9 years) were treated using Class III intermaxillary elastics and bilateral miniplates (two in the infra-zygomatic crests of the maxilla and two in the anterior mandible). The subjects had cone beam computed tomographs (CBCTs) taken before initial loading (T1) and 1 year out (T2). Twenty-eight untreated Class III patients (mean age, 12.4 years) had CBCTs taken and cephalograms generated. The airway volumes and minimum cross-sectional area measurements were performed using Dolphin Imaging 11.7 3D software. The superior border of the airway was defined by a plane that passes through the posterior nasal spine and basion, while the inferior border included the base of the epiglottis to the lower border of C3. Results: From T1 to T2, airway volume from BAMP-treated subjects showed a statistically significant increase (1499.64 mm3). The area in the most constricted section of the airway (choke point) increased slightly (15.44 mm2). The airway volume of BAMP patients at T2 was 14136.61 mm3, compared with 14432.98 mm3 in untreated Class III subjects. Intraexaminer correlation coefficients values and 95% confidence interval values were all greater than .90, showing a high degree of reliability of the measurements. Conclusion: BAMP treatment did not hinder the development of the oropharynx.

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VASIU, Teodor, Adina BUDIUL BERGHIAN e Corneliu BIRTOK BANEASA. "Determining the Maintainability of Burning Ovens from Cement Factory". Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science 44, n. 2 (15 giugno 2021): 17–23. http://dx.doi.org/10.35219/mms.2021.2.03.

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For any industrial entity put into operation, it is of interest to its ability to fulfil its mission under certain conditions, at a given time or during a given period of time, assuming that the means of maintenance are provided. This represents availability and is a complex form of system / product quality, as it includes both reliability and maintainability. Availability can be increased by: maximum reliability, maintenance, respectively by maximum maintainability, correct use of equipment / machines, renewal, optimization of reliability and maintainability characteristics, but provided that such balancing does not lead to contradictory solutions. The availability of a product will be higher the more reliable it is and requires less maintenance. It should be borne in mind that in order to ensure a certain level of reliability, maintenance costs must not exceed 10...20% of the purchase price of the product each year [1]. Restoration of reliability to a normal level is achieved through corrective or preventive maintenance. In practice, a compromise is sought between the purchase price, the service imposed and the accepted risk, as in order to achieve availability through reliability, very reliable parts must be used, which cost 5-10 times more than usual [2]. Maintenance-based availability results from the consideration that reliability is a probability of trouble-free operation over a period of time. Reliability is technically and financially limited. Defects in the initial period of operation of the product, as well as those in the final period derive from inevitable physical phenomena, and defects in the maturity period have a normal accidental character. In addition, the reliability can deteriorate over time even during storage, thus causing additional damage. Reliability is restored to its normal level through corrective or preventive maintenance, as failures are foreseeable or unpredictable. Product availability is the result of a combination of reliability and maintainability and they support each other. Increasing the maintainability of products leads to increased availability. In this case, the real maintainability of a burning oven of a cement factory was studied, with the aim of finding practical solutions to increase the service life. Achieving the proposed objective required monitoring the operation / failure of such equipment for nine months and statistical processing of the information obtained.

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Feng, Cheng, Da Li Wang e Jin Li. "Development of Back-to-Back Flexible HVDC Prototype Based on MMC". Applied Mechanics and Materials 397-400 (settembre 2013): 1808–13. http://dx.doi.org/10.4028/www.scientific.net/amm.397-400.1808.

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With the development of flexible HVDC technology in the world, back-to-back HVDC system based on MMC topology have more attention. A high power back-to-back flexible HVDC prototype has been developed to assess performance and reliability of construction of converter valve segment. Valve normal working condition (rated conditions rated voltage, current, temperature), valve transient working condition (temporary overvoltage, overcurrent), valve fault protection and anti-interference ability are accessed. Performance and reliability of control and protection equipment are assessed. The design of control and protection strategy is optimized. The correctness of main circuit design is tested.

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Bink, Thijs, Merel H. J. Hazewinkel, Caroline A. Hundepool, Liron S. Duraku, Judith Drenthen, Lisa Gfrerer e J. Michiel Zuidam. "Feasibility of Ultrasound Measurements of Peripheral Sensory Nerves in Head and Neck Area in Healthy Subjects". Plastic and Reconstructive Surgery - Global Open 11, n. 10 (ottobre 2023): e5343. http://dx.doi.org/10.1097/gox.0000000000005343.

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Background: Current diagnostic methods for nerve compression headaches consist of diagnostic nerve blocks. A less-invasive method that can possibly aid in the diagnosis is ultrasound, by measuring the cross-sectional area (CSA) of the affected nerve. However, this technique has not been validated, and articles evaluating CSA measurements in the asymptomatic population are missing in the current literature. Therefore, the aim of this study was to determine the feasibility of ultrasound measurements of peripheral extracranial nerves in the head and neck area in asymptomatic individuals. Methods: The sensory nerves of the head and neck in healthy individuals were imaged by ultrasound. The CSA was measured at anatomical determined measurement sites for each nerve. To determine the feasibility of ultrasound measurements, the interrater reliability and the intrarater reliability were determined. Results: In total, 60 healthy volunteers were included. We were able to image the nerves at nine of 11 measurement sites. The mean CSA of the frontal nerves ranged between 0.80 ± 0.42 mm2 and 1.20 ± 0.43 mm2, the mean CSA of the occipital nerves ranged between 2.90 ± 2.73 mm2 and 3.40 ± 1.91 mm2, and the mean CSA of the temporal nerves ranged between 0.92 ± 0.26 mm2 and 1.40 ± 1.11 mm2. The intrarater and interrater reliability of the CSA measurements was good (ICC: 0.75–0.78). Conclusions: Ultrasound is a feasible method to evaluate CSA measurements of peripheral extracranial nerves in the head and neck area. Further research should be done to evaluate the use of ultrasound as a diagnostic tool for nerve compression headache.

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Abdul Rashid, Aneesa, Rusli Nordin, Khairil Idham Ismail, Ahmad Munir Qureshi, Ahmad Filza Ismail, Shaw Voon Wong e Navin Kumar Devaraj. "Driving Behaviour, Road Crash Involvement, Working Commute (MyDRIVE) Questionnaire: Testing Data Quality, Scaling Assumptions, Reliability and Validity Among Malaysian Medical Doctors". Primary Care Endeavour in Healthcare 19, s17 (20 dicembre 2023): 25–32. http://dx.doi.org/10.47836/mjmhs.19.s17.4.

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Introduction: The Driving Behaviour, Road Crash Involvement, Working Commute (MyDRIVE) questionnaire was developed to assess medical doctors’ experience with road crash involvement. The objective of this research was to validate the driving behavioural component of MyDRIVE for medical practitioners in Malaysia. Method: This was a multi-stage study involving item specification, domain specification and domain assessment. Following item pools among the experts, Malaysian Medical Association (MMA) members and their contacts who are partially or fully registered with the Malaysian Medical Council (MMC) were surveyed via an online questionnaire between April 2020 and May 2021. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) was done with 150 participants and 824 participants, respectively on separate analysis to ensure the factor validity. We examined the standardized loadings, AVE and CR to determine the convergent validity. The discriminant validity was tested through the Fornell-Larcker matrix. Reliability analysis was performed through Cronbach alpha and composite reliability. Results: EFA resulted in reduction of items from 44 items to 23 items with six constructs. Composite reliability (CR) revealed all domains have a CR of above 0.7, except for Driving Under Alcohol Influence (DAI) (0.605). The remaining factors are Distracted Mind & Negative Emotion (DMNE) (0.843), Safe Driving Habit (SDH) (0.862), Fatigue Driving (FD) (0.903), Recreational & Prescribed Driving (RPD) (0.748), and Driving Under Influence of Caffeine (DCI) (0.836). For discriminant validity the square root of AVE for all constructs were greater than its correlations with other latent constructs. Conclusion: Our study finds the driving behavioural component of the MyDRIVE questionnaire among the Malaysian medical doctors to have good reliability and validity. Future studies should consider using MyDRIVE’s driving behaviour component to assess driving behaviour among doctors.

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Ried, L. Douglas, e Richard E. Johnson. "Evaluation of the Reliability and Validity of a Measure of Anxiolytic Drug-Use Intensity for Pharmacoepidemiologic Studies". Annals of Pharmacotherapy 26, n. 11 (novembre 1992): 1441–46. http://dx.doi.org/10.1177/106002809202601118.

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OBJECTIVE: To assess the reliability and validity of a proposed new standard of drug-use intensity, the minimum marketed dose (MMD), using anxiolytic drugs as models. DESIGN: Retrospective, cohort design. SETTING: Staff model, nonprofit health maintenance organization. PATIENTS/PARTICIPANTS: Eighty-five patients who obtained one or more prescriptions for an anxiolytic, antidepressant, or sedative-hypnotic drug during three consecutive one-year time periods. Fifty-nine patients had a prescription filled during the year before the study. RESULTS: For anxiolytic drugs, the magnitude of the average correlation for the MMD measure of drug-use intensity was greater than the total number of prescriptions and the total number of dosage units. Discriminant validity was demonstrated because the MMD was not correlated with measures in unrelated therapeutic categories. Summed MMD units were shown to significantly predict physical impairment (criterion validity). CONCLUSIONS: The MMD measure of drug-use intensity was reliable and valid for anxiolytic drugs. These findings suggest that information gathered from automated prescription records may be a useful indicator of drug-use intensity in pharmacoepidemiologic studies.

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Cooley, Jeffrey R., Clark D. Danielson, Gary D. Schultz e Timothy A. Hall. "Posterior disk displacement: Morphologic assessment and measurement reliability—lumbar spine". Journal of Manipulative and Physiological Therapeutics 24, n. 5 (giugno 2001): 317–26. http://dx.doi.org/10.1067/mmt.2001.115266.

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Cooley, Jeffrey R., Clark D. Danielson, Gary D. Schultz e Timothy A. Hall. "Posterior disk displacement: Morphologic assessment and measurement reliability—cervical spine". Journal of Manipulative and Physiological Therapeutics 24, n. 9 (novembre 2001): 560–68. http://dx.doi.org/10.1067/mmt.2001.118981.

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Kokmeyer, Dirk J., Peter van der Wurff, Geert Aufdemkampe e Theresa C. M. Fickenscher. "The reliability of multitest regimens with sacroiliac pain provocation tests". Journal of Manipulative and Physiological Therapeutics 25, n. 1 (gennaio 2002): 42–48. http://dx.doi.org/10.1067/mmt.2002.120418.

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Christensen, Henrik Wulff, Werner Vach, Kirstin Vach, Claus Manniche, Torben Haghfelt, Lisbet Hartvigsen e Poul Flemming Høilund-Carlsen. "Palpation of the upper thoracic spine: An observer reliability study". Journal of Manipulative and Physiological Therapeutics 25, n. 5 (giugno 2002): 285–92. http://dx.doi.org/10.1067/mmt.2002.124424.

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