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31.
Narongsak Yotha Qusain Hiader Zulqurnain Sabir Muhammad Asif Zahoor Raja Salem Ben Said Qasem Al-Mdallal Thongchai Botmart Wajaree Weera 《计算机、材料和连续体(英文)》2023,74(2):2415-2430
This study aims to solve the nonlinear fractional-order mathematical model (FOMM) by using the normal and dysregulated bone remodeling of the myeloma bone disease (MBD). For the more precise performance of the model, fractional-order derivatives have been used to solve the disease model numerically. The FOMM is preliminarily designed to focus on the critical interactions between bone resorption or osteoclasts (OC) and bone formation or osteoblasts (OB). The connections of OC and OB are represented by a nonlinear differential system based on the cellular components, which depict stable fluctuation in the usual bone case and unstable fluctuation through the MBD. Untreated myeloma causes by increasing the OC and reducing the osteoblasts, resulting in net bone waste the tumor growth. The solutions of the FOMM will be provided by using the stochastic framework based on the Levenberg-Marquardt backpropagation (LVMBP) neural networks (NN), i.e., LVMBPNN. The mathematical performances of three variations of the fractional-order derivative based on the nonlinear disease model using the LVMPNN. The static structural performances are 82% for investigation and 9% for both learning and certification. The performances of the LVMBPNN are authenticated by using the results of the Adams-Bashforth-Moulton mechanism. To accomplish the capability, steadiness, accuracy, and ability of the LVMBPNN, the performances of the error histograms (EHs), mean square error (MSE), recurrence, and state transitions (STs) will be provided. 相似文献
32.
Muhammad Faisal Michael B. C. Khoo Ayesha Nayab Raja Fawad Zafar 《Quality and Reliability Engineering International》2023,39(1):472-477
Link relative-based approach was used in an article (see reference 1) to enhance the performance of the cumulative sum (CUSUM) control chart. This technique involves the use of firstly, the link relative variable to convert the process observations in a relative to the mean form and secondly, optimal constants to define a new variable which is used as the plotting statistic of the link relative CUSUM chart. In this article, it is proven through simulation study that the optimal constants with fixed values, as reported in the aforementioned article, give different results. Instead, if the regression technique is used, then the same results will be obtained. 相似文献
33.
D. S. E. J. Dhas R. Raja S. Jannet K. L. D. Wins J. M. Thomas S. R. Kandavalli 《Materialwissenschaft und Werkstofftechnik》2023,54(2):147-157
In this study, aluminium-silicon7-magnesium alloy was reinforced with carbide ceramics (silicon carbide and boron carbide) and coke microparticles. The composite samples (S1, S2, and S3) with 4 %, 8 %, and 12 % by weight of silicon carbide and boron carbide microparticles and 8 % by weight of coke micro particles respectively, were prepared through the ultrasonic assisted melt-stir casting route. It was observed from the literature that only a few research works reported the cumulative effect of adding these micro-particulate reinforcements within aluminium-silicon7-magnesium alloy. The microstructural evaluation revealed uniform dispersion of particulate reinforcements. Area energy dispersive x-ray spectroscopy scan results proved the presence of the reinforcement particles as heterogeneous phases at distinct zones. The samples undergone tensile tests failed under the brittle fracture mode. The ultimate tensile strength of the composites improved by about 27.4 %, the % elongation improved by about 6.8 %, and Vickers microhardness dropped 1.9 % to the maximum. Dimples were observed in the fracture morphology analysis and it was mainly due to the mixed ductility of the sample S2. An abrasive wear mechanism was observed in the worn-out sample S2. The wear rate decreased significantly with an increase in weight fraction of the reinforcements. 相似文献
34.
TA Kim J Lim S Ota S Raja R Rogers B Rivnay H Avraham S Avraham 《Canadian Metallurgical Quarterly》1998,141(3):553-566
The nuclear matrix is defined as the insoluble framework of the nucleus and has been implicated in the regulation of gene expression, the cell cycle, and nuclear structural integrity via linkage to intermediate filaments of the cytoskeleton. We have discovered a novel nuclear matrix protein, NRP/B (nuclear restricted protein/brain), which contains two major structural elements: a BTB domain-like structure in the predicted NH2 terminus, and a "kelch motif" in the predicted COOH-terminal domain. NRP/B mRNA (5.5 kb) is predominantly expressed in human fetal and adult brain with minor expression in kidney and pancreas. During mouse embryogenesis, NRP/B mRNA expression is upregulated in the nervous system. The NRP/B protein is expressed in rat primary hippocampal neurons, but not in primary astrocytes. NRP/B expression was upregulated during the differentiation of murine Neuro 2A and human SH-SY5Y neuroblastoma cells. Overexpression of NRP/B in these cells augmented neuronal process formation. Treatment with antisense NRP/B oligodeoxynucleotides inhibited the neurite development of rat primary hippocampal neurons as well as the neuronal process formation during neuronal differentiation of PC-12 cells. Since the hypophosphorylated form of retinoblastoma protein (p110(RB)) is found to be associated with the nuclear matrix and overexpression of p110(RB) induces neuronal differentiation, we investigated whether NRP/B is associated with p110(RB). Both in vivo and in vitro experiments demonstrate that NRP/B can be phosphorylated and can bind to the functionally active hypophosphorylated form of the p110(RB) during neuronal differentiation of SH-SY5Y neuroblastoma cells induced by retinoic acid. Our studies indicate that NRP/B is a novel nuclear matrix protein, specifically expressed in primary neurons, that interacts with p110(RB) and participates in the regulation of neuronal process formation. 相似文献
35.
Aging and imperfections provide important visual cues for realism. We present a novel physically‐based approach for simulating the biological aging and decay process in fruits. This method simulates interactions between multiple processes. Our biologically‐derived, reaction‐diffusion model generates growth patterns for areas of fungal and bacterial infection. Fungal colony spread and propagation is affected by both bacterial growth and nutrient depletion. This process changes the physical properties of the surface of the fruit as well as its internal volume substrate. The fruit is physically simulated with parameters such as skin thickness and porosity, water content, flesh rigidity, ambient temperature, humidity, and proximity to other surfaces. Our model produces a simulation that closely mirrors the progression of decay in real fruits under similar parameterized conditions. Additionally, we provide a tool that allows artists to customize the input of the program to produce generalized fruit simulations. 相似文献
36.
OBJECTIVE: Effects of four types of automation support and two levels of automation reliability were examined. The objective was to examine the differential impact of information and decision automation and to investigate the costs of automation unreliability. BACKGROUND: Research has shown that imperfect automation can lead to differential effects of stages and levels of automation on human performance. Method: Eighteen participants performed a "sensor to shooter" targeting simulation of command and control. Dependent variables included accuracy and response time of target engagement decisions, secondary task performance, and subjective ratings of mental work-load, trust, and self-confidence. RESULTS: Compared with manual performance, reliable automation significantly reduced decision times. Unreliable automation led to greater cost in decision-making accuracy under the higher automation reliability condition for three different forms of decision automation relative to information automation. At low automation reliability, however, there was a cost in performance for both information and decision automation. CONCLUSION: The results are consistent with a model of human-automation interaction that requires evaluation of the different stages of information processing to which automation support can be applied. APPLICATION: If fully reliable decision automation cannot be guaranteed, designers should provide users with information automation support or other tools that allow for inspection and analysis of raw data. 相似文献
37.
Effect of nitrogen addition on the microstructure and mechanical behavior of 317L and 904L austenitic stainless steel welds 总被引:1,自引:0,他引:1
A systematic study of the effect of nitrogen addition on the microstructure and mechanical behavior of two different austenitic
stainless steel welds, namely, 317L and 904L was carried out. For this, nitrogen content of the welds was altered by introducing
different proportions of nitrogen gas into the argon shielding gas during welding. Nitrogen addition to 317L weld changed
solidification mode from primary ferrite to primary austenite. As 904L weld solidify by primary austenitic mode, no change
in the solidification mode was found with N addition. The results showed that, with rise in nitrogen content of the welds,
various mechanical properties like ultimate tensile strength and ductility had improved significantly and that the welds prepared
with 1 vol% N2 in the shielding gas indeed failed in the base alloy making the weld stronger than the parent metal. It was noticed that
the effect of N towards improving the mechanical properties 904L weld was higher than that found in the case of 317L weld. 相似文献
38.
Sabdar Aman Chowdhury Himadri Sekhar Maiti Sampad Biswas 《Journal of Materials Science》2006,41(15):4699-4705
A novel approach has been taken to produce (1) spherical Al2O3 particles by decarbonisation and (2) spherical AlN particles by nitridation and subsequent decarbonisation of C@Al2O3 composite particles. C@Al2O3 composite particles have been prepared by heterogeneous nucleation and crystallisation of Al(NO3)3 on surfactant encapsulated carbon nano particles followed by evaporative decomposition of the nitrate. Overpressure (0.4 MPa) of nitrogen and a temperature range (1723–1873 K) have been used for nitridation. Whiskers as well as spherical particles of AlN have been observed in the final product. The final product has been characterised by X-Ray Diffraction, Scanning Electron Microscope and Carbon–Hydrogen–Nitrogen content analysis by Elemental Analyser and the mechanism of the nitridation reaction has been analysed. The average size of the spherical AlN particles consisting of crystallites in nano-dimensions (30–50 nm) could be varied from 100 nm to 8 μm by changing the composition of the sol. 相似文献
39.
Intracranial aneurysms have a high prevalence in the adult population; and if they rupture, significant morbidity almost always ensues. However, pulsatile blood flow through aneurysms produces vibrational sound patterns that may be detected extracranially. Thus, an acoustic aneurysm-detector has been developed to detect the sounds produced by intracranial aneurysms prior to rupture. The design is based on the utilization of a hydrophone for signal detection and computational signal processing for signal extraction. Data are examined in the time domain, the frequency domain, and the time-frequency plane. Examples are presented from an animal model and from a patient with a known aneurysm. 相似文献
40.