235 research outputs found
R PEAK DETERMINATION USING A WDFR ALGORITHM AND ADAPTIVE THRESHOLD
The determination of the R peak position in the ECG signal helps physicians not only to know the heart rate per minute, but also to monitor the patient’s health related to heart disease. This paper proposes a system to accurately determine the R peak position in the ECG signal. The system consists of a pre-processing block for filtering out noise using a WDFR algorithm and highlighting the amplitude of the R peak and a threshold value is calculated for determining the R peak. In this research, the MIT-BIH ECG dataset with 48 records are used for evaluation of the system. The results of the SEN, +P, DER and ACC parameters related to the system quality are 99.70%, 99.59%, 0.70% and 99.31%, respectively. The obtained performance of the proposed R peak position determination system is very high and can be applied to determine the R peak of the ECG signal measuring devices in practice
Optimization of Rough Self-Propelled Rotary Turning Parameters in terms of Total Energy Consumption and Surface Roughness
The self-propelled rotary tool turning (SPRT) process is an economic and effective solution for machining difficult-to-cut materials. This work optimized SPRT parameters, including the inclination angle (A), depth of cut (D), feed rate (f), and turning speed (V) to decrease the total energy consumption (TE) and surface roughness (SR). The turning experiments of the hardened AISI 4150 steel were executed to obtain the experimental data, while the regression method was applied to develop the TE and SR correlations. The entropy method and quantum-behaved particle swarm optimization (QPSO) were utilized to select the weights and optimal factors. The results indicated that the optimal A, D, f, and V were 34 deg., 0.40 mm, 0.47 mm/rev., and 177 m/min, respectively, while the TE and SR were saved by 9.7% and 35.4%, respectively. The f and V were found to be the most effective parameters, followed by the D and A. The outcomes provide valuable data to determine optimal SPRT factors for minimizing energy consumption and maximizing machining quality.The optimizing technique could be applied to solve other issues for different SPRT operations
Multi-Response Optimization of the Flat Burnishing Process with a High-Stiffness Tool in terms of Surface Characteristics
In this work, the surface roughness (SR), surface hardness (SH), and the thickness of the affected layer (TL) of the multi-roller flat burnishing process are optimized.The parameter inputs are the tool rotational speed (S), burnishing depth (D), and feed rate (f). The flat burnishing tool having three rollers was utilized to facilitate burnishing trials. The Kriging models of performances are proposed regarding inputs.The CRITIC method and Crow Search Algorithm (CSA) were employed to select weights and optimality. The optimizing outcomes indicated that the optimal values of the S, f, and D were 912 rpm, 150 mm/min, and 0.12 mm, respectively. The improvements in the SR, SH, and TL were 33.3%, 26.9%, and 48.6%, respectively. The SR was primarily influenced by the f, followed by the D and S, respectively. The SH and TL were primarily influenced by the D, followed by the S and f, respectively. The optimal data could be applied to the practical multi-roller burnishing process to improve surface properties for flat surfaces. The Kriging models and CSA could be efficiently utilized to solve complex issues for burnishing operations and other machining processes
DEVELOPMENT AND EVALUATION OF ORAL SUSTAINED-RELEASE RANITIDINE DELIVERY SYSTEM BASED ON BACTERIAL NANOCELLULOSE MATERIAL PRODUCED BY KOMAGATAEIBACTER XYLINUS
Objective: The short biological half-life (2-3 h) and low bioavailability (50 %) of ranitidine (RAN) following oral administration favor the development of a controlled release system. This study was aimed to develop and in vitro evaluate oral sustained-release RAN delivery system based on the bacterial nanocellulose material (BNM) produced by Komagataeibacter xylinus (K. xylinus) from selected culture media.
Methods: BNMs are biosynthesized by K. xylinus in the standard medium (SM) and coconut water (CW). RAN was loaded in BNMs by the absorption method. The structural and physicochemical properties of BNMs and BNMs-RAN were evaluated via swelling behavior, FTIR, and FESEM techniques. Moreover, the effect of BNMs on RAN release profile and release kinetics was analyzed and evaluated.
Results: The amount of loaded RAN or entrapment efficacy for BNM-CW is higher than for BNM-SM. The BNM-SM-RAN and BNM-CW-RAN exhibited a decreased initial burst release system followed by a prolonged RAN release up to 24 h in relation to the commercial tablets containing RAN. The RAN release from these formulations was found higher in the SGF medium than that of in SIF medium. RAN released from these formulations was found to follow the Korsmeyer-Peppas model and diffusion sustained drug release mechanism. The sustained release of RAN from BNM-SM-RAN was slower than for RAN from BNM-CW-RAN, but the mechanism of sustained RAN release was the same.
Conclusion: Oral sustained-release RAN delivery system based on BNMs was successfully prepared and evaluated for various in vitro parameters. The biopolymers like BNM-SM and BNM-CW could be utilized to develop oral sustained RAN release dosage form
Delving into Ipsilateral Mammogram Assessment under Multi-View Network
In many recent years, multi-view mammogram analysis has been focused widely
on AI-based cancer assessment. In this work, we aim to explore diverse fusion
strategies (average and concatenate) and examine the model's learning behavior
with varying individuals and fusion pathways, involving Coarse Layer and Fine
Layer. The Ipsilateral Multi-View Network, comprising five fusion types (Pre,
Early, Middle, Last, and Post Fusion) in ResNet-18, is employed. Notably, the
Middle Fusion emerges as the most balanced and effective approach, enhancing
deep-learning models' generalization performance by +2.06% (concatenate) and
+5.29% (average) in VinDr-Mammo dataset and +2.03% (concatenate) and +3%
(average) in CMMD dataset on macro F1-Score. The paper emphasizes the crucial
role of layer assignment in multi-view network extraction with various
strategies
Ecpoc: an evolutionary computation-based proof of criteria consensus protocol
Recently, blockchain technology has been applied in many domains in our life. Blockchain networks typically utilize a consensus protocol to achieve consistency among network nodes in a decentralized environment. Delegated Proof of Stake (DPoS) is a popular mechanism adopted in many networks such as BitShares, EOS, and Cardano because of its speed and scalability advantages. However, votes that come from nodes on a DPoS network tend to support a set of specific nodes that have a greater chance of becoming block producers after voting rounds. Therefore, only a small group of nodes can be selected to become block producers. To address this issue, we propose a new protocol called Evolutionary Computation-based Proof of Criteria (ECPoC), which uses ten criteria to evaluate and select a new block procedure in each round. Next, a set of optimal weights used for maximizing the network’s decentralization level is identified through the use of evolutionary computation algorithms. The experimental results show that our consensus significantly enhances the degree of decentralization in the selection process of witness nodes compared to DPoS. As a result, ECPoC facilitates fairness between nodes and creates momentum for blockchain network developmen
Coping with noise in joint remote preparation of a general two-qubit state by using nonmaximally entangled quantum channel
Noise is unavoidable in practice and its presence makes quantum protocols imperfect. In this paper we consider a way to cope with typical types of noise in joint remote preparation of an arbitrary 2-qubit state. The idea is to use nonmaximally (in stead of maximally) entangled states as the initial quantum channel. Because noise changes the initial quantum channel we can beforehand tailor it to be nonmaximally entangled by introducing free parameters which, depending on given types of noise, can be controlled so that due to the affect of noise the initial quantum channel becomes closest to the maximally entangled one, thus optimizing the performance of the joint remote state preparation protocol. The dependence of the optimal averaged fidelities on the strength of various types of noise is represented by phase diagrams that clearly separate the quantum domain from the classical one
The results of deep magnetotelluric sounding for studying the Nha Trang - Tanh Linh fault
The profile of deep magnetotelluric sounding (MT) from Duc Trong - Tuy Phong has been carried out in Lam Dong and Binh Thuan provinces. The length of the Duc Trong - Tuy Phong profile is about 80 km with 15 stations and the distance between the stations measures about 5 km. Two-dimensional MT inversion was used to find a resistivity model that fits the data. The 2D resistivity model allows determining position and development formation of the Nha Trang - Tanh Linh fault. This is the deep fault, which is showed by the boundaries of remarkable change of resistivity. In the near surface of the Earth (from ground to the depth of 6 km), the angle of inclination of this fault is about 60o; in the next part, the direction of the Nha Trang - Tanh Linh faut is vertical. Geoelectrical section of the Nha Trang - Tanh Linh profile shows that the resistivity of mid-crust is higher than that of lower-crust and of upper-crust
An Empirical Study of Affective Commitment: the Case of Machinery Enterprises in Hochiminh City
The study aims to investigate the impact of participation in decision-making (PDM) and perceived organizational support (POS) on affective commitment in machinery enterprises. The study applies structural equation modeling (SEM) to test the research hypotheses. The authors surveyed 220 employees who work in machinery enterprises to collect data for the research. The study results indicate that both PDM and POS positively impact affective commitment. The findings provide empirical evidence to support the theoretical models that PDM and POS have a positive effect on affective commitment. The findings have implications for management theory: PDM and POS are the key antecedents of affective commitment. The findings also have implications for practical management in the machinery enterprises that managers should practice both PDM and POS to increase affective commitment
XÁC ĐỊNH TẦNG CHỨA VÀ QUAN TRẮC BIẾN ĐỘNG MÔI TRƢỜNG NƢỚC DƢỚI ĐẤT TẠI KHU CÔNG NGHIỆP BẮC THĂNG LONG - QUANG MINH, HÀ NỘI BẰNG PHƢƠNG PHÁP ĐỊA VẬT LÝ THỦY VĂN
Geophysical methods were applied for hydrogeological targets in many countries including Vietnam. This paper resents results of using complex geophysical techniques as well as 2D electrical resistivity imaging (ERI), vertical electrical sounding (VES), very low frequency (VLF) and seismic refraction for geological structure investigation to aquifers locate and to assess of hydrogeological condition for groundwater potential in North Thanglong and Quangminh industrial zones, Hanoi, Vietnam. The locations of two aquifers are determined by their depth and thickness on the basis of resistivity and seismic velocity values which were proved by stratifications of three boreholes to 40-60m of depth on study area. There are connecting from surface water to shallow aquifer by hydraulic windows from VLF data. The deeper aquifer can be considered as potential groundwater for supplying in the area. Groundwater level, electrical conductivity and water temperature were measured in six monitoring wells, complemented by anion, cation and stable isotope analyses of ground and surface water. This study also reviews, compiles and comprehensively analyzes spatiotemporal variations of hydrological and hydrogeological characteristics of shallow and deep groundwater aquifers in area and in nearby Red River water. The results show that groundwater in both shallow and deep aquifers was fresh, but mainly calcium-bicarbonate type. With the goal of devising sustainable water use regulations, more research must be directed toward long-term monitoring of groundwater and surface water quality, as well as toward detailed investigation of the hydraulic characteristics of local aquifers in the study area.ReferencesAGI, 2003. The SuperSting with Swift automatic resistivity and IP system instruction manual, Advanced Geosciences, Inc., Austin, Texas, U.S.A.Lê Đức An, 1996. 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An integrated geophysical investigation of the hydrogeology of an anisotropic unconfined aquifer. J. of Hydrology. 267, 227-243. Telford, W.M.; L.P. Geldart, R.E. Sheriff, 1990. Applied Geophysics (2nd ed.), 480. Vickery A., Hobbs B.A., 2003. Resistivity imaging to determine clay cover and permeable units at an ex-industrial site. Near Surface Geophys., 1, 21-30. WTO, 2004. Guidelines for drinking water quality; Training Pack, WTO, Geneva, Switzerland. Geophysical methods were applied for hydrogeological targets in many countries including Vietnam. This paper presents results of using complex geophysical techniques as well as 2D electrical resistivity imaging (ERI), vertical electrical sounding (VES), very low frequency (VLF) and seismic refraction for geological structure investigation to aquifers locate and to assess of hydrogeological condition for groundwater potential in North Thanglong and Quangminh industrial zones, Hanoi, Vietnam. The locations of two aquifers are determined by their depth and thickness on the basis of resistivity and seismic velocity values which were proved by stratifications of three boreholes to 40-60m of depth on study area. There are connecting from surface water to shallow aquifer by hydraulic windows from VLF data. The deeper aquifer can be considered as potential groundwater for supplying in the area. Groundwater level, electrical conductivity and water temperature were measured in six monitoring wells, complemented by anion, cation and stable isotope analyses of ground and surface water. This study also reviews, compiles and comprehensively analyzes spatiotemporal variations of hydrological and hydrogeological characteristics of shallow and deep groundwater aquifers in area and in nearby Red River water. The results show that groundwater in both shallow and deep aquifers was fresh, but mainly calcium-bicarbonate type. With the goal of devising sustainable water use regulations, more research must be directed toward long-term monitoring of groundwater and surface water quality, as well as toward detailed investigation of the hydraulic characteristics of local aquifers in the study are
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