Limited Dimensions Research Articles

Full mouth rehabilitation of the patient with severely worn dentition and limited vertical dimension

Full mouth rehabilitation of the patient with severely worn dentition and limited vertical dimension

A powder delivery system for large-scale DED machines

Additive Manufacturing (AM) technologies are constantly increasing in terms of applications and market volume; especially metal AM volume has more than doubled in the last 2 years. However, AM machines still remain hampered by their limited build volume dimensions and relatively low build rates, poor quality and uncertainty of final part mechanical properties. A key process aspect for the majority of the AM processes is the deposition rate, deposition rate control and the achievable deposition “spot”. The present study is focused on the improvement of the configuration and design of the process head and the delivery system of a DED machine emphasizing on optimum deposition rate through the implementation of a process model and CFD simulations.

Lightweight Speaker Recognition in Poincaré Spaces

This letter proposes a lightweight model for speaker recognition by leveraging a hyperbolic space. The speaker recognition performance heavily depends on the distinctiveness of speaker embeddings induced by metric learning. However, most state-of-the-art embedding methods are typically based on the Euclidean metric space, which does not account for inherent hierarchical structures of speech voice characteristics. The recent development of the neural hyperbolic geometry has demonstrated its effectiveness to model continuous hierarchical structures, which have been typically cumbersome to model by standard deep neural networks. This facet provides an additional by-product of a compact representation. Inspired by the favorable geometry of the hyperbolic geometry, we developed a hyperbolic ResNet for speaker recognition. We found that in smaller dimension regimes than typical cases, the learned speaker embeddings are more discriminative; in other words, more compact at the same level of performance. Our experiments on the large-scale VoxCeleb datasets show that, given the limited channel dimensions of neural networks, our method consistently has favorable performance against the standard ResNet for both speaker recognition and verification tasks.

Stochastically Flipping Labels of Discriminator’s Outputs for Training Generative Adversarial Networks

Generative Adversarial Networks (GANs) play the adversarial game between two neural networks: the generator and the discriminator. Many studies treat the discriminator’s outputs as an implicit posterior distribution prior to the input image distribution. Thus, increasing the discriminator’s output dimensions can represent richer information than a single output dimension of the discriminator. However, increasing the output dimensions will lead to a very strong discriminator, which can easily surpass the generator and break the balance of adversarial learning. Solving such conflict and elevating the generation quality of GANs remains challenging. Hence, we propose a simple yet effective method to solve this conflict problem based on a stochastic selecting method by extending the flipped and non-flipped non-saturating losses in BipGAN. We organized our experiments based on the famous BigGAN model for comparison. Our experiments successfully validated our approach to strengthening the generation quality within limited output dimensions via several standard evaluation metrics and real-world datasets and achieved competitive results in the Human face generation task.

Secret Key Generation by Continuous Encryption Before Quantization

Secret key generation (SKG) is a fundamental signal processing problem for security applications including wireless network security and biometric template security. For SKG, a pair (or more) of highly correlated secret vectors (SVs) need to be respectively quantized into a pair (or more) of almost identical sequences of binary bits (i.e., keys). The literatures on SKG in the wireless community almost uniformly default on a direct quantization on the SVs. On the other hand, many works on biometric template security advocate a quantization on the output of a one-way transformation of SVs. In this paper, we present a generalized approach for SKG called continuous encryption before quantization (CEbQ). By CEbQ, a pair of SVs of limited dimension are first transformed by a continuous encryption function into a pair of sequences of quasi-continuous pseudorandom numbers (QCPRNs) of any desired length, and then these QCPRNs are quantized into keys. We show that CEbQ can yield a much lower key error rate than direct quantization subject to standardized randomness tests. Comparisons with other related methods are also provided.

Pathologic Examination of Pancreatic Specimens Resected for Treated Pancreatic Ductal Adenocarcinoma: Recommendations From the Pancreatobiliary Pathology Society.

Currently, there are no internationally accepted consensus guidelines for pathologic evaluation of posttherapy pancreatectomy specimens. The Neoadjuvant Therapy Working Group of Pancreatobiliary Pathology Society was formed in 2018 to review grossing protocols, literature, and major issues and to develop recommendations for pathologic evaluation of posttherapy pancreatectomy specimens. The working group generated the following recommendations: (1) Systematic and standardized grossing and sampling protocols should be adopted for pancreatectomy specimens for treated pancreatic ductal adenocarcinoma (PDAC). (2) Consecutive mapping sections along the largest gross tumor dimension are recommended to validate tumor size by histology as required by the College of American Pathologists (CAP) cancer protocol. (3) Tumor size of treated PDACs should be measured microscopically as the largest dimension of tumor outer limits that is bound by viable tumor cells, including intervening stroma. (4) The MD Anderson grading system for tumor response has a better correlation with prognosis and better interobserver concordance among pathologists than does the CAP system. (5) A case should not be classified as a complete response unless the entire pancreas, peripancreatic tissues, ampulla of Vater, common bile duct, and duodenum adjacent to the pancreas are submitted for microscopic examination. (6) Future studies on tumor response of lymph node metastases, molecular and/or immunohistochemical markers, as well as application of artificial intelligence in grading tumor response of treated PDAC are needed. In summary, systematic, standardized pathologic evaluation, accurate tumor size measurement, and reproducible tumor response grading to neoadjuvant therapy are needed for optimal patient care. The criteria and discussions provided here may provide guidance towards these goals.

Definition of a unified material model for cellular materials with high morphological and topological dispersion: Application to an AA7075-T6 aluminium foam

The compression behaviour in quasi-static and dynamic conditions of cellular materials is crucial for their applications both for ensuring structural strength and high energy absorption capability. Despite the recent progress made in understanding the experimental observations, analytical and numerical modelling still requires improvements in the Representative Volume Element (RVE) identification that can be uncertain due to the limited dimensions of the investigated specimens and to the cell inhomogeneity.The objective of this paper is to implement a material model able to consider the statistical distribution so that its effect can be quantitatively highlighted, mitigating uncertainty of the RVE identification.The applied methodology started with morphological and topological analyses on samples extracted from an ingot of AA7075T6 foam, which was manufactured by compact powder technology. Quasi-static and dynamic experimental compression tests have been carried out and compared with 3D mesoscale numerical simulations in order to correlate the mechanical behaviour of the foam to the cell characteristics. Finally, an equivalent material model, which is a function of the statistical distributions of cells morphology and topology, has been proposed and analytically verified.

ZnO Quantum Dot/MXene Nanoflake Hybrids for Ultraviolet Photodetectors

Efficacious utility of fugacious photons within a limited dimension of photoactive semiconductor thin films provides a facile approach to break through the obstacle for the sensitivity improvement of photodetection. Herein, we demonstrate a facile way to fabricate ZnO quantum dot (QD)/MXene nanoflake photodetectors by uniformly blending various ratios of two-dimensional (2D) Ti3C2Tx nanoflakes into ZnO QD thin films, which can establish a carrier transportation highway and light confinement centers within the photoactive layers. The light absorption of hybrid thin films is obviously enhanced because of the localized surface plasmon resonance effect of MXene nanoflakes, resulting in an expressively enhanced external quantum efficiency by 35 times for the device with 0.1 mg/mL 2D Ti3C2Tx nanoflakes (150.0%) in comparison with that of the pristine photodetector (4.3%). Under 350 nm light illumination (1.72 mW cm–2), the carrier transportation in ZnO thin films is significantly accelerated with the hot electron injection from the high-conductivity 2D Ti3C2Tx nanoflakes and thereby the optimal responsivity of 425 mA/W with an improved response speed at 10 V. Furthermore, ZnO QD/MXene nanoflake photodetectors also exhibit an excellent long-term stability. This work provides an efficient method to fabricate high-performance ZnO UV photoelectric devices in the military and civilian fields at low light intensities.

KARAKTERISTIK GLULAM BAMBU BETUNG (Dendrocalamus asper) MENGGUNAKAN PEREKAT STYROFOAM BERDASARKAN JUMLAH LAPISAN DAN POLA PENYUSUNAN

Bamboo is one of the non-timber natural forest products that has the potential to be used as raw material for wood substitutes because bamboo has many advantages. If for wood with high durability, it takes time from planting seedlings to be ready for harvest is 30-40 years and even then after cutting down the seeds must be planted again, but bamboo takes up to 4-5 years to be ready to be harvested. The problem that arises is that bamboo has a limited dimension so that it requires lamination technology that can shape bamboo into a dimensioned material according to construction needs. Lamination technology is an alternative way of processing bamboo that is relevant to achieving the expected goals. Lamination can make the strength of betung bamboo far higher than solid wood blocks. Tests carried out by physical and mechanical tests of betung bamboo lamination using JAS 234: 2003. Testing the physical properties of the betung bamboo includes a wood density test for moisture content testing, and thickness swelling. The mechanical properties of the betung bamboo include the modulus of rupture and modulus of elasticity tests. The lamination test has variations in the number of layers A1 (3 layers), A2 (5 layers), and A3 (7 layers) with 3 replications each. Betung bamboo density obtained an average of 0.316 gr/cm3 to 0.453 gr/cm3, the average moisture content of betung bamboo was 11.386% to 12.444%, and the average thickness swelling test was 0.240% to 0.293%. Modulus of rupture test is 210,160 kg/cm2 to 925,963 kg/cm2, and the modulus of elasticity test shows an average of 0.916 kg/cm2 to 925,963 kg/cm2. The physical properties of the betung bamboo (Dendrocalamus asper) meet the JAS 234: 2003 standard is the moisture content, for the density and thickness swelling bamboo betung lamination is not required in the JAS 234: 2003 standard. The mechanical properties of betung bamboo laminate for MOE values are equivalent to wood strength classes II-IV and MOR are equivalent to wood strength classes V

Anomaly detection in random circuit patterns using autoencoder

Background: Systematic/stochastic pattern defects affect the production yield of integrated circuits (IC) containing trillions of 10-nm level features. Aim: We detect pattern anomalies/defects from images obtained from scanning electron microscopes (SEM) for random/arbitrary IC patterns without using design data. Approach: We decompose SEM images into small sub-images and apply an identical autoencoder to each of them to detect anomalies. The astronomical varieties in random IC patterns are reduced into limited varieties in elementary patterns, which are coded onto limited dimension latent vectors in autoencoder. The discrepancy between autoencoder input and output represents a deviation of local pattern shapes from ideal or allowed ones and is used as an index of anomaly. Results: A wide variety of anomalies/defects are detected in regular and random IC patterns fabricated by extreme ultra-violet lithography without prior knowledge about anomalies at a high signal-to-noise ratio within a time shorter than the typical image acquisition time of SEMs. They include missing/necking in holes/trenches, collapsing/breaking in lines, various local pattern distortion/deformation, and tiny particles. Frequency and spatial distributions of the discrepancy index are sensitive to process changes and can be used for visualizing the sign or causes of anomalies. Conclusions: The method is effective for inspecting memory and random logic ICs with high-speed SEMs.

Accuracy of CBCT in the Identification of Mental, Lingual, and Retromolar Foramina: A Comparison with Visual Inspection of Human Dry Mandibles

The present dry-mandible study evaluated the presence of the mental (MF), lingual (LF), and retromolar (RMF) foramina to assess the accuracy of CBCT in detecting these anatomical structures. In total, 38 human dry mandibles were analyzed (30 men, 8 women; mean age: 61.9 ± 13.7 years). CBCT scans were taken using low-dose parameters, and LF, MF, and RMF were assessed visually and radiographically. Both the presence (yes/no) and the count (n) of each foramen were compared between CBCTs and visual assessment. For the presence assessment, only RMF exhibited a significant difference between CBCT and visual inspection (P = .035). For count, the RMF (P = .049) and paramedian LF (P = .003) exhibited differences between the two methods. The agreement between CBCT and visual inspection was excellent for the MF, moderate-excellent for the LF, and low-moderate for the RMF. Intra- and interassessor agreement varied from excellent (MF), to moderate-excellent (LF), and low-moderate (RMF). The LF and RMF represent challenging structures to identify on CBCT images due to their limited dimension. False negative findings in CBCTs in the assessment of foramina, especially LF, might lead to surgical complications during implant surgery.

Retraction Note to: Change of offshore surface water temperature characteristics based on Bayesian regression and physical recovery of sports training

In this paper, a simple Bayesian distribution regression learning framework based on probability multi-scale kernel (RMK-BDR) is proposed to study the variation of offshore surface water temperature characteristics and the physical recovery of sports training based on Bayesian regression, which can solve the distribution regression problem of complex data. In the first stage of distributed regression learning, the average embedded estimator of the limited dimension of the same dimension is introduced. Through this method, the number of optimal center points can be adaptively selected according to the sample set, so as to avoid the influence on the sample size of inconsistent regression modeling. Climate change is the most important environmental problem in today’s society. The East China Sea and its adjacent Northwest Pacific have a very important impact on China’s climate. In recent years, it has gradually evolved into an area of international concern. The ocean can transport the heat storage to the atmosphere through the heat exchange between the ocean and the air, promote the movement of the atmosphere through the heat change, and affect the atmospheric cycle. Therefore, it is very important to study the annual and decades’ temporal and spatial variation of sea water temperature around China. At the same time, with the rapid development of basketball, the physical requirements of athletes are also higher and higher. There are many ways to improve the physical strength of basketball players. In addition to scientific training, nutritional support is also an important part. However, for a long time, the lack of understanding of nutritional support and the lack of relevant theoretical support have made nutritional support not fully applied in the basketball field.

Study on Design of Novel Function/Structure Integration Mounting Plate for Space borne SAR Antenna for Wireless Communication

A novel lightweight and high-precision synthetic aperture radar (SAR) antenna mounting plate scheme based on functional structure integration technology is proposed. The thermal control function, high and low frequency blind insertion signal transmission function of the system are combined with the antenna structure to greatly reduce the size and weight of SAR antenna. The design verification of a high-density integrated SAR antenna mounting plate breaks through the key process technologies such as accurate splicing of multiple interfaces of the mounting plate, highly reliable cementation of non-uniform honeycomb and large-scale warpage control, and solves the key technical difficulties of high precision, high temperature and high reliability. The results show that the antenna mounting plate (size 649mm × 430mm) the overall flatness is better than 0.28mm, the thickness limit dimension deviation is less than 0.1mm, and the temperature consistency is less than 1.8°C. It can meet the requirements of lightweight, structural stiffness and strength, RF blind plug connection and heat dissipation for space borne SAR antenna.

Forgery detection algorithm based on texture features

Any researcher's goal is to improve detection accuracy with a limited feature vector dimension. Therefore, in this paper, we attempt to find and discover the best types of texture features and classifiers that are appropriate for the coarse mesh finite differenc (CMFD). Segmentation-based fractal texture analysis (SFTA), local binary pattern (LBP), and Haralick are the texture features that have been chosen. K-nearest neighbors (KNN), naïve Bayes, and Logistics are also among the classifiers chosen. SFTA, local binary pattern (LBP), and Haralick feature vector are fed to the KNN, naïve Bayes, and logistics classifier. The outcomes of the experiment indicate that the SFTA texture feature surpassed all other texture features in all classifiers, making it the best texture feature to use in forgery detection. Haralick feature has the second-best texture feature performance in all of the classifiers. The performance using the LBP feature is lower than that of the other texture features. It also shows that the KNN classifier outperformed the other two in terms of accuracy. However, among the classifiers, the logistic classifier had the lowest accuracy. The proposed SFTA based KNN method is compared to other state-of-the-art techniques in terms of feature dimension and detection accuracy. The proposed method outperforms other current techniques.

Tapering the Incident Field When Solving Problems of Electromagnetic Wave Scattering Over Finite-Size Random Surfaces

Introduction. An analysis of radio wave scattering over random surfaces frequently involves integral equations, which are solved by numerical methods. These methods are feasible only provided limited dimensions of the surface. The requirement of surface limitation leads to the appearance of edge currents, resulting in significant errors when calculating the radar cross section (RCS), particularly for grazing incident angles. The influence of edge currents is reduced by a function tapering the incident field amplitude. This function should satisfy the following requirements: to provide a low suppression of the field along the entire finite-size surface between its edges at the same time as decreasing the incident field amplitude to negligible values when approaching the edges. The incident field under the application of the tampering function should satisfy the wave equation with a minimum error. Although various tapering functions are applied for incident field amplitude (i.e. Gaussian, Thorsos, integral), none of them satisfies the aforementioned requirements.Aim. To suggest a novel function for tapering the amplitude of an electromagnetic wave incident on a perturbed finite-size surface when calculating RCS. In comparison with the known functions, the proposed function must satisfy the entire set of requirements.Materials and methods. A comparison of the proposed tapering function for incident field amplitude with the known tapering functions was performed, including the estimation of the error of satisfying the wave equation. To prove the applicability of the proposed tapering function, a mathematical modeling of the bistatic scatter diagram of a two-dimensional sea-like finite surface with a spatial Elfouhaily spectrum was carried out using Monte Carlo calculations in the Matlab environment.Results. Compared to the known tapering functions, the proposed tapering function satisfies the entire set of requirements. The results of mathematical modeling showed that the proposed function for tapering the incident field amplitude provides acceptable accuracy of estimating the RCS of finite-size random surfaces.Conclusion. A novel function for tapering the incident field amplitude was derived. This function reduces the influence of edge currents on the accuracy of RCS estimation of two-dimensional finite-size random surfaces, thus being instrumental for solving scattering problems.

Factors associated with influenza vaccine coverage among patients with diabetes: Korea National Health and Nutrition Examination Survey 2016-2018.

BackgroundAlthough the influenza vaccine has been proven to be effective, this common disease has high morbidity and mortality rates. Moreover, adults with diabetes are at a high risk of influenza-mediated morbidity and mortality.Purpose of the studyWith the increasing prevalence of diabetes, influenza is more lethal in diabetics; thus, we aimed to investigate the factors associated with influenza vaccination coverage in patients with diabetes.MethodsCross-sectional data were obtained from the Korea National Health and Nutrition Examination Survey (2016–2018). We retrospectively analyzed whether sociodemographic, health-related, and medical factors are associated with influenza vaccination coverage in patients with diabetes. We performed a complex sample logistic regression analysis and estimated the odds ratios (ORs) by adjusting for statistically significant factors.ResultsThe number of survey subjects was 18,553. The vaccine coverage rate among patients with diabetes was 60.6%. In the univariate analysis, sex, educational level, smoking, exercise, drinking, marital status, private health insurance, activity limit, economic activity, age, and EuroQol-5 Dimension scores, which were used to assess health-related quality of life, were associated with vaccination coverage. In the multivariate analysis, only age and economic activity were associated with vaccination coverage. The vaccination coverage rate was higher for people who did not undertake economic activities and who were older (OR 1.512 (1.087–2.105), OR 2.212 (1.822–2.686), respectively, p < 0.001).ConclusionNational interventions involving public health centers are necessary to encourage influenza immunization for patients with diabetes, especially younger patients and those who work or undertake economic activities.

Overlapped joints in Textile Reinforced Concrete with UHPC matrix: An experimental investigation

When producing a Textile Reinforced Concrete structure or element, joining separate textile layers might be a necessity, driven for example by the limited dimensions of commercially available fabrics. A possible way of producing such joints is by overlapping different textile sheets. Overlapped joints, however, need to be cast with particular attention since they might represents weak elements of the structure, leading to premature failure. An experimental campaign was performed, aimed at identifying the effects of a symmetric vs non-symmetric arrangement of the textile fabrics within the overlapping length and tensile characteristics of the matrix on such type of joints. Fifteen specimens, produced using a fully epoxy impregnated carbon textile fabric and an Ultra High Performance Concrete (UHPC) matrix, were tested under tension in a uniaxial setup and measurements were performed using a Digital Image Correlation system. The in-plane and out-of-plane behaviour of each specimen was studied. The results highlight the importance of producing symmetric elements as well as the beneficial effects that the admixture of short dispersed steel fibres to the cementitious matrix provide to such kind of joints

Passive fuel cell/lithium-ion capacitor hybridization for vehicular applications

Electric recreational vehicles represent a new challenge in terms of power supply systems compared to the current light-duty electric vehicles, which achieve high performance and long-range. The recreational vehicles need to heed the limited dimension requirements while assuring the high requested power. This paper proposes an integration of Lithium-Ion Capacitor (LIC) with Fuel Cell (FC) without any power electronic device for a three-wheel electric motorcycle. Unlike other hybrid power supply systems, the proposed FC-LIC passive configuration is lighter, compact, more efficient, and simpler to implement. Due to the different impedance of the components the system is self-management, in which FC supplies the average power component and LIC operates as a low-pass filter. In this respect, a simulator is built based on experimental tests to study the system performance in terms of hydrogen consumption and FC degradation. Subsequently, the system is tested under three standard motorcycle driving cycles at three different FC system lifespan stages. The obtained results demonstrate that a passive topology can supply the requested power along different FC stages of life and reported just an increment of 12% of hydrogen consumption at the oldest condition compared to the new condition.

High-strength hierarchical-structured bulk nanoporous Cu prepared by dealloying and spark plasma sintering

The applications of dealloyed nanoporous metals are usually hindered by their slow rate of synthesis, the limited sample dimensions, and the poor mechanical stability due to the presence of native cracks. We report that these obstacles can be overcome by combining dealloying with spark plasma sintering. Centimeter-sized nanoporous Cu samples were prepared by spark plasma sintering of dealloyed nanoporous Cu particles. The obtained bulk nanoporous Cu samples are free of major cracks, and exhibit hierarchical porous structures with structure size of ∼250 nm at lower level of hierarchy and relative density varying between 0.29∼0.57. Because of the "size effect" on ligament strength and the elimination of native cracks, these nanoporous Cu samples are stronger than monolithic nanoporous Cu (with cracks) and microporous Cu of similar density. We anticipate that this approach will improve the performance and broaden the application of nanoporous metals, of which the synthesis rate, sample dimensions and microstructure are no longer dependent entirely on dealloying procedure.

USE OF THE MAGNETORESISTIVE MAGNETIC FIELD SENSORS FOR THE TESTING OF THE LINEAR INDUCTION MOTORS

The magnetic field of an LIM is more complex than that of a rotating induction motor. At analysis of LIM the limited dimensions of the inductor should be considered. Therefore, it is necessary to investigate the magnetic fields beyond the inductor boundaries (edge effect and end effect), and interdependencies of these fields. Because of the phenomenon of end effect, additional factors must be considered: there is a reduction of attraction force, and despite a balanced supply voltage, increased phase impedance and phase differences of leading currents. The first task is to measure the magnetic field parameter of LIM by using a hall sensor and CMR.