scholarly journals Design of Positioning Mechanism Fit Clearances Based on On-Orbit Re-Orientation Accuracy

2019 ◽  
Vol 9 (21) ◽  
pp. 4712 ◽  
Author(s):  
Qingya Li ◽  
Libao Yang ◽  
Weiguo Zhao ◽  
Zhen Shi ◽  
Zhenyu Liu
Keyword(s):  
Numerical Simulation ◽  
Mathematical Models ◽  
Relative Position ◽  
Rotation Angle ◽  
Design Method ◽  
Test Results ◽  
Test Environment ◽  
Factors Affecting ◽  
Relationship Of ◽  
Optical Unit

The factors affecting the re-orientation accuracy of the on-orbit replaceable optical unit were studied, and the mathematical models of the relationships between fit clearances of positioning mechanisms and the limits of rotation angles were deduced. When the relative position relationship of positioning mechanisms was determined, fit clearances were designed according to the requirement of the rotation angle limits, and the rotation angle limits were determined to ensure that the angles were within the index range. Theodolites were used to measure the re-orientation angles of the optical unit, and the errors between the measurement angles and the real angles were deduced. Then, the numerical simulation proved that the errors were within limits. The microgravity test environment was established, and the weight of the optical unit was unloaded by a suspension method to simulate the state of the optical unit when it was replaced on orbit. The test results confirmed the correctness of the design method.

scholarly journals HUBUNGAN POLA ASUH ORANG TUA DENGAN KEMATANGAN EMOSI REMAJA DI SMA N 1 SINONSAYANG

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Nikita Lumenta ◽  
Herlina I.S Wungouw ◽  
Michael Karundeng
Keyword(s):  
Design Method ◽  
Sampling Techniques ◽  
Test Results ◽  
Chi Square ◽  
Cross Sectional ◽  
Emotional Maturity ◽  
Chi Square Test ◽  
And Control ◽  
Relationship Of ◽  
The Relationship

Abstrack Emotional maturity is a person's ability to control and control his emotions well.This is based on a condition of feeling or reaction feeling stable towards an object of theproblem so that to take a decision or behavior based on a consideration. One of the factorsthat influence emotional maturity is parenting which is divided into three types, namelyauthoritarian parenting, permissive parenting, and democratic parenting. The purpose of thisstudy was to determine the relationship of parenting parents with the emotional maturity ofadolescents in SMA N 1 Sinonsayang. The design method uses a cross sectional approach.Respondents consisted of 95 teenagers with sampling techniques using total sampling. Datacollection using a questionnaire. Chi Square Test Results with a confidence level of 95% v (α0.05), where the value of p = 0,018 is smaller than α = 0.05. The conclusion is there is arelationship between parenting parents and adolescent emotional maturity in SMA N 1SinonsayangKeywords: Parenting patterns, emotional maturity, adolescenceAbstrak Kematangan emosi adalah kemampuan seseorang dalam mengontrol danmengendalikan emosinya secara baik. Hal ini didasari sebagai suatu kondisi perasaan ataureaksi perasaan yang stabil terhadap suatu objek permasalahan sehingga untuk mengambilsuatu keputusan atau tingkah laku didasari dengan suatu pertimbangan. Salah satu faktor yangmempengaruhi kematangan emosi adalah pola asuh orang tua yang terbagi dalam tiga tipe,yaitu pola asuh otoriter, pola asuh permisif, dan pola asuh demokratis. Tujuan penelitian iniadalah mengetahui hubungan pola asuh orang tua dengan kematangan emosi remaja di SMAN 1 Sinonsayang. Metode penelitian menggunakan pendekatan cross sectional. Respondenterdiri dari 95 remaja dengan teknik pengambilan sampel menggunakan Total Sampling.Pengumpulan data menggunakan kuesioner. Hasil Uji Chi Square dengan tingkatkepercayaan 95%v(α 0,05), dimana nilai p = 0,018 lebih kecil dari α = 0,05. Kesimpulan adahubungan antara pola asuh orang tua dengan kematangan emosi remaja di SMA N 1Sinonsayang.Kata Kunci: Pola asuh orang tua, Kematangan emosi, Remaja.

Numerical Simulation of UHPFRC-NSC Composite Beam with Diana

2011 ◽  
Vol 243-249 ◽  
pp. 6040-6043
Author(s):  
Yi Hong Guo ◽  
Gang Ling Hou ◽  
Nan Guo
Keyword(s):  
Numerical Simulation ◽  
Material Properties ◽  
Composite Beam ◽  
Shear Force ◽  
Three Dimensional ◽  
Crack Model ◽  
Test Results ◽  
Shear Connection ◽  
Relationship Of ◽  
Push Out

This paper presents three-dimensional numerical simulation of UHPFRC-NSC composite beam with Diana. An elastic-plastic fracture model is proposed to describe material properties of UHPFRC. Differing from other concrete constitutive model, this one considers strain hardening in tension because of characteristic of UHPFRC. A total strain rotating crack model is used to describe material properties of NSC. The results of relevant push-out tests are used to describe the shear force-slip relationship of shear connection between UHPFRC girder and NSC slab. The numerical investigation focuses on the evaluation of load-deflection behavior, failure mode and shear connection. The agreement of test results and numerical results indicates the reliability of model.

Design of High-Speed Magnetic Pump Based on the Numerical Simulation

2009 ◽  
Author(s):  
Fanyu Kong ◽  
Zhiqiang Wang ◽  
Cuilan Gao ◽  
Hongli Zhang
Keyword(s):  
Numerical Simulation ◽  
High Speed ◽  
High Efficiency ◽  
Design Method ◽  
Internal Flow ◽  
Magnetic Coupling ◽  
Magnetic Vector Potential ◽  
Test Results ◽  
Working Situation ◽  
The Magnetic Field

The high-speed magnetic pump has the characteristic of zero leakage, small volume and high efficiency. In order to enhance the performance of high-speed magnetic pump and shorten the design period, the hydraulic components and magnetic coupling are designed on the basis of numerical simulation. The hydraulic components designed initially are applied by the design method of high-speed partial emission pump. The internal flow field of the pump is simulated with the FLUENT CFD software. The distributions of absolute velocity, relative velocity and total pressure of pump are gained. The inlet structure and geometry of the magnetic pump are modified based on the simulation results. The magnetic coupling is designed by using empirical factors. The magnetic field of the magnetic coupling is simulated with 2-D Magnetic Vector Potential (MVP) formula using the ANSYS software. The distributions of magnetic force line at origin, working situation and maximum magnetic rotating angle are obtained. The magnetic torque simulated value approaches the result calculated with the empirical formula. The test results of the improved magnetic pump show that the hydraulic performance and outline dimensions meet requirements. The method of design-simulation-improvement-test is successful.

Design Method of the Parameters of Tools for Clinching Technology

2012 ◽  
Vol 455-456 ◽  
pp. 1491-1496 ◽  
Author(s):  
Bai Jun Shi ◽  
Ye Qing Wang ◽  
Song Lin Liu ◽  
Heng Yu Tian
Keyword(s):  
Shear Test ◽  
Design Method ◽  
Process Variable ◽  
Local Deformation ◽  
Fe Analysis ◽  
Test Results ◽  
Joining Technology ◽  
Joint Resistance ◽  
Mechanical Clinching ◽  
Relationship Of

The mechanical clinching process was a new alternative method for metal sheet joining technology which geometrically constrains two sheets by local deformation. The tools geometry was crucial since it directly influences the joint resistance. How to determine the value of the tools parameters was always the difficulty. In view of this, a fast and efficient tools design method was proposed in this paper based on the mechanical relationship of process variable and FE-analysis technology. Besides, the tensile test and shear test results were shown in this study for proving the validity of the method which indicated that this design method could meet the requirements of the joint resistance and would bring much more convenience in clinching tools design.

Study on Numerical Simulation of Internal Flow Field for the Multi Blade Centrifugal Fan

2014 ◽  
Vol 525 ◽  
pp. 251-255 ◽  
Author(s):  
Sheng Li Zhang ◽  
Hua Xing Li
Keyword(s):  
Numerical Simulation ◽  
Flow Field ◽  
Design Theory ◽  
Design Method ◽  
Internal Flow ◽  
Numerical Results ◽  
Centrifugal Fan ◽  
Test Results ◽  
Traditional Design ◽  
Design Program

This paper points out that the traditional design method of multi blade centrifugal fan are great uncertainty in selecting the structure parameters: lead to many design results, do many tests. Internal flow field of multi blade centrifugal fan was simulated with the computational fluid dynamics software Fluent, and the numerical results are analyzed. Comparison of the numerical results with the test results shows that numerical simulation has good accuracy and reliability. The design program and a design example is gived according to the design theory of multi blade centrifugal fan. Method is verified by numerical simulation for the example. Test results show that the design program is reliable.

Manipulate Me

2020 ◽  
Vol 36 (4) ◽  
pp. 554-562
Author(s):  
Alica Thissen ◽  
Frank M. Spinath ◽  
Nicolas Becker
Keyword(s):  
High School Students ◽  
Spatial Ability ◽  
Convergent Validity ◽  
Item Difficulty ◽  
Test Results ◽  
Response Elimination ◽  
School Students ◽  
Test Environment ◽  
Response Options ◽  
Construction Task

Abstract. The cube construction task represents a novel format in the assessment of spatial ability through mental cube rotation tasks. Instead of selecting the correct answer from several response options, respondents construct their own response in a computerized test environment, leading to a higher demand for spatial ability. In the present study with a sample of 146 German high-school students, we tested an approach to manipulate the item difficulties in order to create items with a greater difficulty range. Furthermore, we compared the cube task in a distractor-free and a distractor-based version while the item stems were held identical. The average item difficulty of the distractor-free format was significantly higher than in the distractor-based format ( M = 0.27 vs. M = 0.46) and the distractor-free format showed a broader range of item difficulties (.02 ≤  pi ≤ .95 vs. .37 ≤  pi ≤ .63). The analyses of the test results also showed that the distractor-free format had a significantly higher correlation with a broad intelligence test ( r = .57 vs. r = .17). Reasons for the higher convergent validity of the distractor-free format (prevention of response elimination strategies and the broader range of item difficulties) and further research possibilities are discussed.

Problematic Internet Use digunakan Ketika Kesepian pada Remaja

2020 ◽  
Vol 14 (1) ◽  
pp. 45-60
Author(s):  
Yashinta Yashinta ◽  
Dwi Hurriyati
Keyword(s):  
Internet Use ◽  
Hypothesis Test ◽  
Problematic Internet Use ◽  
Coefficient Of Determination ◽  
Test Results ◽  
Research Subjects ◽  
Significance Level ◽  
Relationship Of ◽  
The Relationship ◽  
Effective Contribution

This study aims to determine the relationship of loneliness with problematic internet use on boarding students on Silaberanti street in Siantan jaya Opposite Ulu 1 Palembang city. Research subjects numbered 220 people using random sampling methods. Data was collected using a 60 item problematic internet use scale and a 60 item loneliness. Realibility is generated on scale of problematic internet use of 0,955 and loneliness of 0,946.Hypothesis testing uses product moment correlation analysis techniques. Hypothesis test results showed a positive relationshif between loneliness with problematic internet use on boarding students on Silaberanti street in Siantan jaya Opposite Ulu 1 Palembang city r= 0,684 with a significance level of 0,000 (p<0,01). Loneliness in this study made an effective contribution of 46,8% to problematic internet use which can be seen from the coefficient of determination (r²) that is equel to 0,468.

scholarly journals Experiment and simulation about the effect of wear-ring abrasion on the performance of a marine centrifugal pump

2021 ◽  
Vol 13 (2) ◽  
pp. 168781402199811
Author(s):  
Wu Xianfang ◽  
Du Xinlai ◽  
Tan Minggao ◽  
Liu Houlin
Keyword(s):  
Numerical Simulation ◽  
Centrifugal Pump ◽  
Pressure Pulsation ◽  
Vibration Velocity ◽  
Test Results ◽  
Obvious Effect ◽  
Performance Change ◽  
Pump Test ◽  
Simulation Results ◽  
Axis Passing

The wear-ring abrasion can cause performance degradation of the marine centrifugal pump. In order to study the effect of front and back wear-ring clearance on a pump, test and numerical simulation were used to investigate the performance change of a pump. The test results show that the head and efficiency of pump decrease by 3.56% and 9.62% respectively at 1.0 Qd due to the wear-ring abrasion. Under 1.0 Qd, with the increase of the front wear-ring the vibration velocity at pump foot increases from 0.4 mm/s to 1.0 mm/s. The axis passing frequency (APF) at the measuring points increases significantly and there appears new characteristic frequency of 3APF and 4APF. The numerical simulation results show that the front wear-ring abrasion affects the flow at the inlet of the front chamber of the pump and impeller passage. And the back wear-ring abrasion has obvious effect on the flow in the back chamber of the pump and impeller passage, while the multi-malfunction of the front wear-ring abrasion and back wear-ring abrasion has the most obvious effect on the flow velocity and flow stability inside pump. The pressure pulsation at Blade Passing Frequency (BPF) of the three schemes all decrease with the increase of the clearance.

Experimental study of moment carrying behavior of typical Tibetan timber beam-column joints

2021 ◽  
pp. 136943322110015
Author(s):  
Ting Guo ◽  
Na Yang ◽  
Huichun Yan ◽  
Fan Bai
Keyword(s):  
Bending Moment ◽  
Structural Performance ◽  
Test Results ◽  
Timber Beam ◽  
Rotational Stiffness ◽  
Trilinear Model ◽  
Column Joint ◽  
Loading Tests ◽  
The Moment ◽  
Relationship Of

This study aimed to investigate the moment carrying behavior of typical Tibetan timber beam-column joints under monotonic vertical static load and also evaluate the influence of length ratio of Gongmu to beam (LRGB) and dowels layout on the structural performance of the joint. Six full-scale specimens were fabricated with same construction but different Gongmu length and dowels position. The moment carrying performance of beam-column joints in terms of failure mode, moment resistance, and rotational stiffness of joints were obtained via monotonic loading tests. Test results indicated that all joints are characterized by compressive failure perpendicular to grain of Ludou. Additionally, it was found that greater LRGB leads to greater initial rotational stiffness and maximum moment of the joint by an increase of restraint length for beam end; however, offsetting dowels toward column resulted smaller stiffness and ultimate bending moment of joints, particularly, offsetting Beam-Gongmu dowels toward column changed the moment-rotation curve pattern of the beam-column joint, accompanied by a hardening stiffness at last phase. Furthermore, a simplified trilinear model was proposed to represent the moment-rotation relationship of the typical Tibetan timber beam-column joint.

Improving the Strength of Abrasive Wheels and Optimizing the Control over the Strength of Composite Abrasive Materials

2019 ◽  
Vol 946 ◽  
pp. 380-385
Author(s):  
Boris A. Chaplygin ◽  
Viacheslav V. Shirokov ◽  
Tat'yana A. Lisovskaya ◽  
Roman A. Lisovskiy
Keyword(s):  
Mechanical Properties ◽  
Test Results ◽  
Key Factors ◽  
Special Equipment ◽  
Material Density ◽  
Factors Affecting ◽  
Control Factors ◽  
Reinforcing Material ◽  
Special Studies ◽  
First Time

The strength of abrasive wheels is one of the key factors affecting the performance of abrasive machining. The paper discusses ways to improve the strength of abrasive wheels. The stress-state mathematical model presented herein is a generalization of the existing models. It is used herein to find for the first time that there are numerous optimal combinations of the elastic modulus and reinforcing material density, which result in the same minimum value of the objective function. It is found out that increasing the radius of the reinforcing component while also optimizing the mechanical properties of its material may increase the permissible breaking speed of the wheel several times. We herein present a regression equation and a nomogram for finding the optimal combination of control factors. Conventional methods for testing the mechanical properties of materials, which have been proven reliable for testing metals and alloys, are not as reliable for testing abrasive materials, as the test results they generate are not sufficiently stable or accurate. We therefore propose an alternative method that does not require any special equipment or special studies.

Sign in / Sign up

Export Citation Format

Share Document