Virtual Prototyping Simulation of Flexible Multi-Point Auxiliary Support Fixture for Blade Machining

2014 ◽  
Vol 496-500 ◽  
pp. 1256-1259 ◽  
Author(s):  
Yan Cao ◽  
Jing Li ◽  
Jian Hui Tian ◽  
Qing Ming Fan
Keyword(s):  
Cutting Force ◽  
High Reliability ◽  
Virtual Prototyping ◽  
Light Weight ◽  
Machining Quality ◽  
The Poor ◽  
Blade Machining ◽  
Thin Walled ◽  
Processing Difficulty

Spatial curved blades have been widely used in major aerospace manufacturers due to their light weight, high structural efficiency, high reliability, etc. However, their processing deformation, processing difficulty, and so on limit their use. In order to deal with the situation, flexible multi-point auxiliary supporting fixture for the processing of spatial curved thin-walled parts has become a major topic of current researches. The layout of positioning and clamping points of the flexible multi-point fixture direct affects the stiffness of clamping positions on the thin-walled parts to be processed. When cutting force is definite at a certain point in machining, the greater the stiffness at the processing positions on the part, the smaller the processing deformation due to the cutting force. Therefore, in order to reduce the machining deformation due to the poor stiffness, a suitable positioning and clamping layout is needed to improve the surface stiffness at the machining positions. Thus, the machining quality of thin-walled parts can be improved.

scholarly journals Manufacturing Parts for Hydraulic Systems of Agricultural Machinery under Conditions of Ultrasonic Cutting

2020 ◽  
Vol 30 (4) ◽  
pp. 624-636
Author(s):  
Vladimir A. Skryabin
Keyword(s):  
Cutting Force ◽  
Cutting Speed ◽  
Special Device ◽  
Hydraulic Systems ◽  
Agricultural Machinery ◽  
Part Surface ◽  
Processing Accuracy ◽  
Thin Walled ◽  
Ultrasonic Cutting

Introduction. The article deals with the problem of reducing the efforts when processing thin-walled bushings for hydraulic systems of agricultural machines with the ultrasonically activated cutting tool to achieve the specified processing accuracy and surface roughness of parts. Materials and Methods. The article describes the technological standards for ultrasonic cutting. To assess the change in the tangential cutting force, a special device was developed to activate ultrasonically the tool for tangential cutting and corresponding experiments were carried out. Results. An upgrading of a screw-cutting lathe equipped with a special device for ultrasonic cutting of low rigidity thin-walled parts is currently being carried out. The upgraded lathe consists of blocks for processing and measuring experimental research data connected to a personal computer. The upgraded lathe allows evaluating the change in cutting forces under traditional turning and ultrasonic cutting to achieve the specified accuracy and roughness of the part surface during the processing process. Discussion and Сonclusion. Processing low rigidity parts on the modernized equipment has shown that providing the effective conditions of manufacturing thin-walled bushings for agricultural machinery (cutting depth and cutting speed) decreases radial and tangential components of the cutting force that helped to reduce the energy consumption of the cutting process and to stabilize quality of the processing.

Study on the Effect of Vibration Amplitude in Two-Dimension Ultrasonic Vibration Cutting

2014 ◽  
Vol 1027 ◽  
pp. 131-135
Author(s):  
Ying Niu ◽  
Feng Jiao ◽  
Jie Li ◽  
Jia Fei Zhang
Keyword(s):  
Cutting Force ◽  
Ultrasonic Vibration ◽  
Two Dimensional ◽  
Bending Vibration ◽  
Vibration Cutting ◽  
Machining Quality ◽  
Hard And Brittle Materials ◽  
Longitudinal Bending ◽  
Ultrasonic Vibration Cutting

Longitudinal-bending complex vibration can be realized by opening chute on the amplitude amplifier pole. Different longitudinal and bending amplitudes can be obtained under different angles and the number of the chutes. Based on the theory of two-dimensional ultrasonic cutting, the effects of the two dimensional amplitude on the cutting characteristics were analyzed experimentally in the paper. Research results show that the amplitudes of longitudinal and bending vibration have a great effect on cutting force and machining quality in two-dimensional ultrasonic vibration cutting of hard and brittle materials. When keeping constant longitudinal amplitude and increasing bending amplitude in a certain extent, the cutting force could be reduced and the machining quality of workpiece could be improved effectively. The research provides relevant basis for designing two-dimensional longitudinal bending vibration cutting system.

scholarly journals V2X Communication System With Non-Orthogonal Multiple Access: Outage Performance Perspective

2021 ◽  
Vol 21 (2) ◽  
pp. 854
Author(s):  
Tu-Trinh Nguyen ◽  
Dinh-Thuan Do
Keyword(s):  
Multiple Access ◽  
High Reliability ◽  
Spectrum Efficiency ◽  
Full Duplex ◽  
Low Latency ◽  
Amplify And Forward ◽  
The Poor ◽  
Term Evolution

<span class="fontstyle0">To achieve low-latency and high-reliability (LLHR) for applications in the vehicle-toeverything (V2X) networks, the non-orthogonal multiple access (NOMA) based Long Term Evolution (LTE)-based is introduced a promising technology. NOMA-V2X provides higher spectrum efficiency compared with the orthogonal multiple access (OMA) based V2X. This study propose two-way relay assisted NOMA-V2X transmission by exploiting amplify-and-forward (AF) and full-duplex. We derive expressions of outage probability to evaluate performance of two vehicles and to improve the quality of service (QoS) for the device with the poor channel conditions. These expressions are further verified by Monte-Carlo simulations.</span> <br /><br />

Vibration Monitoring and Analysis of Thin-Walled Casing Milling

2016 ◽  
Vol 836-837 ◽  
pp. 600-607 ◽  
Author(s):  
Yi Hang Yao ◽  
Bao Hai Wu ◽  
Ming Luo
Keyword(s):  
Vibration Monitoring ◽  
Machining Efficiency ◽  
Machining Parameters ◽  
Workpiece Surface ◽  
Machining Quality ◽  
The Poor ◽  
Thin Walled

Thin-walled elements are widely used in aerospace engines, such as blisk,casing, blade etc. There are significant vibrations while machining because of thesmall thickness and the poor rigidity of thin-walled workpieces which will lead to lowsurface machining quality, low machining efficiency and even worse the huge damageto the workpieces and the tools. Nevertheless, the vibration during milling does nothappen frequently, as it is closely related to the position of the workpiece structureand the machining parameters. The stiffness of the workpiece varies due to thechanging of cutting position. Therefore, vibration only appears in some positionswhen milling thin-walled workpieces. This paper mainly focus on monitoring themachining process in order to analyze the vibration and the position where it occurs.Moreover, with confirming the vibrated position and analyzing the reason of vibration,the paper provides a valid reference to the machining vibration controlling, the qualityand effectiveness of workpiece surface.

Optimization of the cutting force vector during counter milling

2020 ◽  
pp. 49-50
Author(s):  
A.E. Perminov ◽  
S.V. Babin
Keyword(s):  
Cutting Force ◽  
Depth Of Cut ◽  
Force Vector ◽  
Cutting Depth ◽  
Machining Quality ◽  
End Mills

The process of counter milling with cylindrical and end mills is investigated. It was found that in order to improve the accuracy and quality of processing by counter milling, when choosing the cutting depth, it is necessary to take into account the diameter of the cutter and its rigidity. Keywords counter milling, mating surfaces, accuracy, machining quality, cylindrical and end mills, depth of cut, cutter diameter. [email protected]

The Deformation Analysis for Flank Milling of Thin-Walled Rectangle Plate Based on Flexible Force Model

2011 ◽  
Vol 189-193 ◽  
pp. 1555-1561
Author(s):  
Liang Hong Xiao ◽  
Liang Tang ◽  
Zi Hua Hu ◽  
Zheng Kuang ◽  
Ju Long Yuan
Keyword(s):  
End Milling ◽  
Simulation Method ◽  
Flank Milling ◽  
Deformation Analysis ◽  
Force Model ◽  
Machining Quality ◽  
Finite Element Numerical Simulation ◽  
Thin Walled ◽  
Experimental Values

By considering the effects of flank milling deformation on machining quality of thin-walled rectangle plate, the flexible force model of spiral end milling is built on the condition that the influence of part/tool on milling is considered with FE (finite element) numerical simulation method in this paper. Based on the flexible force model, the distribution curve of machining deformation is got by the FE prediction for the flank milling of the thin-walled rectangle plate, and the compensation strategy of CL (cutting location) is established. Some contrast tests between the flexible force model, the deflection simulation and error compensation values to the rigid force model and experimental values of flank milling are performed, respectively. The results indicate that both the flexible force model founded in the paper and the analyzed values of flank milling deflection of thin-walled rectangle plate are reliable, and an effective judgment is provided to advance the machining quality of thin-walled parts.

HUBUNGAN PERAN FAMILY CAREGIVER TERHADAP QUALITAS HIDUP LANSIA

2019 ◽  
Vol 11 (1) ◽  
pp. 51-56
Author(s):  
RIANI PRADARA JATI ◽  
Sekar Farah Nabila
Keyword(s):  
Quality Of Life ◽  
Family Caregiver ◽  
Random Sampling ◽  
Simple Random Sampling ◽  
The Elderly ◽  
Chi Square ◽  
The Poor ◽  
The Family

  Penempatan peran yang baik bagi Family Caregiver sangatlah membantu lansia dalam meningkatkah qualitas hidupnya, meningkatkan motivasi dalam menjalankan hidup Penelitian ini bertujuan Mengetahui hubungan peran Family Caregiver dalam pemenuhan qualitas hidup bagi lansia di Kelurahan Langenharjo Kabupaten Kendal. DesainPenelitianDeskriptifKorelasional menggunakan pendekatan Krosectional,tehnikSamplingStratified Simple Random Sampling dengan karakteristik heterogen, dari populasi mempunyai hak yang sama untuk diseleksi sebagai sampel teknik undianPengambilan data dengan menggunakan kuesioner yang telah diuji validitas dan reliabilitasnya. Uji statistik Chi-square, dengan taraf signifikasi 5%jumlah sampel pada penelitian ini 70 sampel pada Family Caregiver dari 213 populasi yang ada. Hasil penelitian dari 70 responden didapatkan Peran Family Caregiver tidak baik dengan qualitas hidup tidak baik 33 (47,1%), sedangkan Peran Family Caregiver kurang baik dengan qualitas hidup lansia baik 3 (4,3%). Untuk distribusi Peran Family Caregiver kurang baik dengan qualitas hidup lansia tidak baik sebanyak 6 responden (8,6%) sedangkan untuk distribusi Peran Family Caregiver kurang baik dengan qualitas hidup lansia baik sebanyak 23 responden (32,9%). Terakhir, untuk distribusi Peran Family Caregiver baik dengan qualitas hidup lansia tidak baik didapatkan hasil 2 responden (2, 9%) sedangkan untuk distribusi Peran Family Caregiver baik dengan qualitas hidup lansia baik didapatkan hasil 3 responden (4,3%)Menunjukkan nilai ρ value 0,001 (ρ < 0,05) berarti ada hubungan antara dukungan keluarga dengan kepatuhan lansia dalam keikutsertaan posyandu lansia. Disarankan kepada semua Family Cregiver lansia untuk mampu memahami pentingnya perhatian, dukungan bagi lansia dalammeningkatkan qualitas hidup yang lebih baik bagi lansia.   Kata kunci : Peran family caregiver, qualitas hidup, lansia.   ABSTRACT Placement of a good role for Family Caregiver is very helpful for the elderly to improve their quality of life, increase motivation in living life Research Objective: To know the relationship between the role of Family Caregiver in fulfilling quality of life for the elderly in Langenharjo Village, Kendal Regency. Descriptive Correlational Research Design uses a cross sectional approach, Sampling Stratified Simple Random Sampling technique with heterogeneous characteristics, from the population has the same right to be selected as a sample lottery technique Retrieving data using a questionnaire that has been tested for validity and reliability. Test Chi-square statistics, with a significance level of 5% the number of samples in this study 70 samples on the Family Caregiver from 213 populations. Results of the Study Of 70 respondents found the role of Family Caregiver was not good with poor quality of life 33 (47.1%) , while the role of the Family Caregiver is not good with the quality of life of a good elderly 3 (4.3%). For the distribution of the role of Family Caregiver is not good with the quality of life of the poor family as many as 6 respondents (8.6%) while for the distribution of the Role of Family Caregiver is not good with the quality of life of good elderly as many as 23 respondents (32.9%). Finally, the distribution of the Role of Family Caregiver with good quality of life for the poor is obtained by 2 respondents (2, 9%), while the distribution of the Role of Family Caregiver with good quality of life for the elderly is obtained by 3 respondents (4.3%). 0.001 (ρ <0.05) means that there is a relationship between family support and the compliance of the elderly in the participation of the elderly posyandu. It is recommended to all elderly Cregiver families to be able to understand the importance of attention, support for the elderly in improving the quality of life better for the elderly   Keywords: Role of Family Caregiver, Quality of Life, Elderly

An experience of performing spirometry by trained general practitioners

2020 ◽  
pp. 34-36
Author(s):  
M. A. Pokhaznikova ◽  
E. A. Andreeva ◽  
O. Yu. Kuznetsova
Keyword(s):  
General Practitioners ◽  
Quality Criteria ◽  
Poor Quality ◽  
Male Gender ◽  
Study Research ◽  
The Poor ◽  
Quality Of Research ◽  
Forced Expiratory Maneuver ◽  
Maximal Effort

The article discusses the experience of teaching and conducting spirometry of general practitioners as part of the RESPECT study (RESearch on the PrEvalence and the diagnosis of COPD and its Tobacco-related aetiology). A total of 33 trained in spirometry general practitioners performed a study of 3119 patients. Quality criteria met 84.1% of spirometric studies. The analysis of the most common mistakes made by doctors during the forced expiratory maneuver is included. The most frequent errors were expiration exhalation of less than 6s (54%), non-maximal effort throughout the test and lack of reproducibility (11.3%). Independent predictors of poor spirogram quality were male gender, obstruction (FEV1 /FVC<0.7), and the center where the study was performed. The number of good-quality spirograms ranged from 96.1% (95% CI 83.2–110.4) to 59.8% (95% CI 49.6–71.4) depending on the center. Subsequently, an analysis of the reasons behind the poor quality of research in individual centers was conducted and the identified shortcomings were eliminated. The poor quality of the spirograms was associated either with the errors of the doctors who undertook the study or with the technical malfunctions of the spirometer.

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