Development of a decision making system for selection of dental implant abutments based on the fuzzy cognitive map

Dental implant is a medical operation used to restore the functions of damaged or missing teeth. Correct implantation requires the proper selection of size and shape among the implant structures. In this paper, we propose a method of constructing a Web-based decision making system that enables the selection of a suitable type of abutment by taking into account the patient’s anatomical data and preferences that are based on an expert’s knowledge and experience for those patients. After the classification of the types of abutment that can be connected to fixtures of implants, we built a knowledge base and case base library according to the characteristics of osseous tissue and teeth shape to select optimal abutment. Moreover, we introduce a fuzzy cognitive map that takes into consideration expert’s knowledge for factors that affect implantation. After the determination of the cause-and-effect relationship among the concepts of the fuzzy cognitive map, an osseointegration factor with the highest conceptual concentration weight is inferred from the decision making system. In addition, the selection process for abutment is expressed as a decision making tree and then, it is applied for the rule-based reasoning and case-based reasoning. The optimized selection result is finally extracted based on the fuzzy membership function using fuzzy inference.     

Performance analysis of channel estimation for OFDM systems with residual timing offset

The authors present an analysis of the effect of timing offset on channel estimation for comb-type pilot-aided orthogonal frequency division multiplexing (OFDM) systems. Residual timing offset does not negatively affect the channel estimation of the pilot subcarrier, but does corrupt the channel information obtained via interpolation. This paper provides the mean square error (MSE) channel estimation performance when a linear interpolation technique is used in a comb-type pilot-aided OFDM system. Analysis shows that the performance degradation of the channel estimator due to imperfect frame synchronization is dependent on the frequency correlation of the channels and the amount of timing offset     

Sandglass-type product specification management method for supporting modular design of semiconductor manufacturing equipment

The product life cycle for semiconductor manufacturing facilities has been significantly reduced as a result of the technological advancement of the semiconductor manufacturing process and the expansion of its demand. To ensure long-term market competitiveness under this environment, many companies attempt to convert their systems into mass customization production systems. In general, the specification management for semiconductor manufacturing equipment has adopted the method of making the bill of materials structure of the existing equipment into a new one based on the same physical structure and then customizing it according to a customer’s demands in the detail design phase. However, this method results in longer lead times and difficulties maintaining data consistency due to frequent design changes in connection with various derived products. We suggest a sandglass-type product specification management method to efficiently reflect varying and versatile requirements in product development and shorten the design lead time. In addition, we propose a method to support the modular design of semiconductor manufacturing equipment by classifying the standard specifications for a final product into product component and part component specifications. Finally, we develop a closed-loop product specification management system called NEXUS using our method, and apply this system to semiconductor manufacturing processes.

     

Extraction and Regularization of Various Building Boundaries with Complex Shapes Utilizing Distribution Characteristics of Airborne LIDAR Points

This study presents an approach for extracting boundaries of various buildings, which have concave boundaries, inner yards, non‐right‐angled corners, and nonlinear edges. The approach comprises four steps: building point segmentation, boundary tracing, boundary grouping, and regularization. In the second and third steps, conventional algorithms are improved for more accurate boundary extraction, and in the final step, a new algorithm is presented to extract nonlinear edges. The unique characteristics of airborne light detection and ranging (LIDAR) data are considered in some steps. The performance and practicality of the presented algorithm were evaluated for buildings of various shapes, and the average omission and commission error of building polygon areas were 0.038 and 0.033, respectively     

The Effects of Process Temperatures on the Microstructure and Tensile Properties of Warm-Stamped Nb-Bearing Medium-Mn Steel

Metallurgical and Materials Transactions A - The effects of process temperatures for warm stamping, such as annealing (Tann), austenitizing (Taus), and stamping temperatures (Ts), on the tensile...     

Structural Dynamics of C2F4I2 in Cyclohexane Studied via Time-Resolved X-ray Liquidography

The halogen elimination of 1,2-diiodoethane (C₂H₄I₂) and 1,2-diiodotetrafluoroethane (C₂F₄I₂) serves as a model reaction for investigating the influence of fluorination on reaction dynamics and solute–solvent interactions in solution-phase reactions. While the kinetics and reaction pathways of the halogen elimination reaction of C₂H₄I₂ were reported to vary substantially depending on the solvent, the solvent effects on the photodissociation of C₂F₄I₂ remain to be explored, as its reaction dynamics have only been studied in methanol. Here, to investigate the solvent dependence, we conducted a time-resolved X-ray liquidography (TRXL) experiment on C₂F₄I₂ in cyclohexane. The data revealed that (ⅰ) the solvent dependence of the photoreaction of C₂F₄I₂ is not as strong as that observed for C₂H₄I₂, and (ⅱ) the nongeminate recombination leading to the formation of I₂ is slower in cyclohexane than in methanol. We also show that the molecular structures of the relevant species determined from the structural analysis of TRXL data provide an excellent benchmark for DFT calculations, especially for investigating the relevance of exchange-correlation functionals used for the structural optimization of haloalkanes. This study demonstrates that TRXL is a powerful technique to study solvent dependence in the solution phase.     

Gait-based person identification using 3D LiDAR and long short-term memory deep networks

Gait recognition is one measure of biometrics, which also includes facial, fingerprint, and retina recognition. Although most biometric methods require direct contact between a device and a subject, gait recognition has unique characteristics whereby interaction with the subjects is not required and can be performed from a distance. Cameras are commonly used for gait recognition, and a number of researchers have used depth information obtained using an RGB-D camera, such as the Microsoft Kinect. Although depth-based gait recognition has advantages, such as robustness against light conditions or appearance variations, there are also limitations. For instance, the RGB-D camera cannot be used outdoors and the measurement distance is limited to approximately 10 meters. The present paper describes a long short-term memory-based method for gait recognition using a real-time multi-line LiDAR. Very few studies have dealt with LiDAR-based gait recognition, and the present study is the first attempt that combines LiDAR data and long short-term memory for gait recognition and focuses on dealing with different appearances. We collect the first gait recognition dataset that consists of time-series range data for 30 people with clothing variations and show the effectiveness of the proposed approach.     

Synthesis,characterization, and antibacterial property of eco-friendly Ag/cellulose nanocomposite film

This paper reports silver/cellulose nanocomposite film and its antibacterial activity. A wet and porous cellulose film was served as support for silver nanoparticles synthesis by a hydrothermal method. Stable silver nanoparticles were synthesized using the cellulose film acting as both reducing and stabilizing agent without using any toxic chemicals. The characterization of the synthesized nanocomposite proves that silver nanoparticles are not only deposited over the cellulose surface but also nucleated and grew inside the cellulose film. Silver nanoparticle size and distribution were tuned to improve the antibacterial activity, and the synthesized nanocomposite film shows significant antibacterial action.