Generalized Discernibility Function Based Attribute Reduction in Incomplete Decision Systems

A rough set approach for attribute reduction is an important research subject in data mining and machine learning. However, most attribute reduction methods are performed on a complete decision system table. In this paper, we propose methods for attribute reduction in static incomplete decision systems and dynamic incomplete decision systems with dynamically-increasing and decreasing conditional attributes. Our methods use generalized discernibility matrix and function in tolerance-based rough sets

Quality of Water used at pig farms in the Red River delta

peer reviewedA research was carried out to evaluate water quality using at 12 different pig farms in Bac Ninh, Hung Yen and Hai Duong provinces. Water samples were taken in two periods from October to December 2006 and from March to April 2007. Physical and chemical parameters were analysed at the laboratory of the Department of Veterinary Parasitology-Inspection and Hygiene - Hanoi University of Agriculture. The results showed that, all water sources using the pig farms came from underground and a half of which was not processed. Contents of COD(H+), COD(OH-), CO2, Cl- in water in Hai Duong and Bac Ninh were exceeded the hygiene standard. Iron content in water in all three provinces was exceeded the hygiene standard. After using a processed system including artificial rain, H2O2 supplement and filter the content of DO, CO2 and Fe in the water reached the permitted hygiene standard

ffect of the Halothane Allele on Growth Performance of Pigs and its Genotype Frequencies in the Progeny

A total of 395 tail samples of stress negative Piétrain new born piglets from the pig farm of Dong Hiep Haiphong were used to determine halothane genotypes (CC, CT and TT) in order to study the effect of mating type (♂CC×♀CC, ♂CC×♀CT, ♂CT×♀CC, and ♂CT×♀CT) on halothane genotype frequencies. Effects of genotype on live weight (174 pigs of 2 month old, 96 pigs of 5.5 month old), back fat thickness, loin muscle thickness and lean percentage (117 pigs), average daily gain (89 pigs) were also studied. Results showed that the mating type affected halothane genotype frequencies in the progeny. For the mating type ♂CC×♀CT and ♂CT×♀CT, the genotype containing allele T was reduced in the next generation; in the rest two genotypes (♂CC×♀CC and ♂CT×♀CC) the halothane allele frequency in the offspring was consistent with the theoretical frequency. The halothane genotypes CC and CT did not affect live weights at 2.0 and 5.5 months of age, average daily gain, backfat thickness, loin muscle thickness and lean percentage.Peer reviewe

Creating Fatigue Curve for Steel Machine Elements Using Fatigue Test Method with Gradually Increasing Stress Amplitude

In order to create a fatigue curve, the traditional fatigue test method is applied to specimens using a cyclic stress with constant amplitude. However, this method has disadvantages such as the experimental results could not be used because of specimens broken before reaching the expected stress amplitude, or the tests may be stopped before specimen broken because of limitation of time. To overcome this hurdle of the traditional method, a new experimental method using cyclic stress with gradually increasing amplitude was proposed to build the fatigue curve for steel machine elements

Characterization of pig farms in Hung Yen, Hai Duong and Bac Ninh provinces

peer reviewedIn order to characterization of pig farms in the Red River Delta, a study was conducted on 90 pig farms in Hung Yen, Hai Duong and Bac Ninh provinces from June to December 2006. Results show that most of the pig farms had been built for five years with a small size (0.5 hectare per farm). The invested capital was about 300-400 millions VND per farm. Four main sow groups used in the farms included crossbred exotic sows (51.1%), crossbred sow between local and exotic breeds (14.4%), purebred Landrace and Yorkshire breeds (15.6 and 18.9%, respectively). The boars were various (Duroc 30%, Yorkshire 21%, Landrace 13%, PiÐtrain × Duroc 36% and others). The pigs farms were faced with several difficulties such as limited land, lack of invested capital, uncontrolled quality of breeding pigs, high costs of feed, poor hygiene condition and diseases

UAV Relay-Assisted Emergency Communications in IoT Networks: Resource Allocation and Trajectory Optimization

In this paper, a UAV is deployed as a flying base station to collect data from time-constrained IoT devices and then transfer the data to a ground gateway (GW). In general, the latency constraint at IoT users and the limited storage capacity of UAV highly hinder practical applications of UAV-assisted IoT networks. In this paper, full-duplex (FD) technique is adopted at the UAV to overcome these challenges. In addition, half-duplex (HD) scheme for UAV-based relaying is also considered to provide a comparative study between two modes. In this context, we aim at maximizing the number of served IoT devices by jointly optimizing bandwidth and power allocation, as well as the UAV trajectory, while satisfying the requested timeout (RT) requirement of each device and the UAV's limited storage capacity. The formulated optimization problem is troublesome to solve due to its non-convexity and combinatorial nature. Toward appealing applications, we first relax binary variables into continuous values and transform the original problem into a more computationally tractable form. By leveraging inner approximation framework, we derive newly approximated functions for non-convex parts and then develop a simple yet efficient iterative algorithm for its solutions. Next, we attempt to maximize the total throughput subject to the number of served IoT devices. Finally, numerical results show that the proposed algorithms significantly outperform benchmark approaches in terms of the number of served IoT devices and the amount of collected data.Comment: 30 pages, 11 figure

An adaptive hierarchical sliding mode controller for autonomous underwater vehicles

The paper addresses a problem of efficiently controlling an autonomous underwater vehicle (AUV), where its typical underactuated model is considered. Due to critical uncertainties and nonlinearities in the system caused by unavoidable external disturbances such as ocean currents when it operates, it is paramount to robustly maintain motions of the vehicle over time as expected. Therefore, it is proposed to employ the hierarchical sliding mode control technique to design the closed-loop control scheme for the device. However, exactly determining parameters of the AUV control system is impractical since its nonlinearities and external disturbances can vary those parameters over time. Thus, it is proposed to exploit neural networks to develop an adaptive learning mechanism that allows the system to learn its parameters adaptively. More importantly, stability of the AUV system controlled by the proposed approach is theoretically proved to be guaranteed by the use of the Lyapunov theory. Effectiveness of the proposed control scheme was verified by the experiments implemented in a synthetic environment, where the obtained results are highly promising. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Linh Nguyen" is provided in this record*

The scale of the central beach change processes in the west coast of Nha Trang bay

The central beach in west coast of Nha Trang bay has experienced erosion in recent years. The determination of hydrodynamic regime and causes of this beach fluctuation is still an open problem and is concerned by scientists and managers. This study shows the causes and scales of the shoreline change processes based on the results of shoreline change model and the analysis of remote sensing images of shoreline location

Evaluation of Anterior Chamber Depth and Anterior Chamber Angle Changing After Phacoemulsification in the Primary Angle Close Suspect Eyes

BACKGROUND: Phacoemulsification surgery has the ability to deeply alter the segment anterior morphology, especially in eye with shallow anterior chamber (AC), narrow anterior chamber angle (ACA). However, the changes of anterior chamber depth (ACD) and ACA on the close angle suspect eyes after phacoemulsification have not been mentioned in many studies. So, we conduct this research. AIM: To evaluate the alteration in the ACA and ACD after phacoemulsification in the close angle suspect eyes. METHODS: Interventional study with no control group. Subjects were the primary angle closure suspect (PACS) eyes, that were operated by phacoemulsification with intraocular lens (IOL) at Glaucoma Department of VNIO from December 2017 to October 2018. RESULTS: 29 PACS eyes with cataract were operated by phacoemulsification with intraocular lens. After 3 months of monitoring, the average ACD augmented from 2.082 ± 0.244 to 3.673 ± 0.222 mm. AOD500 increase from 0.183 ± 0.088 to 0.388 ± 0.132 μm, AOD750 increased from 0.278 ± 0.105 to 0.576 ± 0.149 μm. The TISA500 enlarged from 0.068 ± 0.033 to 0.140 ± 0.052 mm2, TISA750 enlarged from 0.125 ± 0.052 to 0.256 ± 0.089 mm2 at the third month (p < 0.01). CONCLUSION: Phacoemulsification surgery increases the ACD and enlarged the angle in the PACS eyes

Meat Quality of Lai Sind, Brahman × Lai Sind and Charolais × Lai Sind Cattle Raised in Dak Lak Province

Peer reviewe