Study of Conceptual Design of the Extension Method for Mechanical Products

2002 ◽  
Author(s):  
Yanwei Zhao ◽  
Guoxian Zhang
Keyword(s):  
Conceptual Design ◽  
Design Method ◽  
Extension Method ◽  
The Core ◽  
Function Decomposition ◽  
Core Technology ◽  
Mechanical Products ◽  
Function Expression ◽  
The Given ◽  
Important Significance

On the foundation summing up existing intelligent conceptual design method, this paper puts forward the research content, characters, path, and method of the conceptual design of extension for mechanical products. This paper rounds the core technology of intelligent conceptual design to research the modeling method of extension design in function-principle-layout-configuration. It includes the function expression, function decomposition and synthesis, function illation and decision. The computers are utilized to simulate the human dialectic thought when resolve problems in this method. The given example shows that the extension method has been applied in the field of conceptual design for mechanical products. This method has important significance to resolve the bottleneck problem of theory studying and engineering realizing of intelligent CAD.

Conceptual Design Method Based on Behavior Re-Creation

2007 ◽  
Vol 10-12 ◽  
pp. 198-202
Author(s):  
H.B. Miao
Keyword(s):  
Conceptual Design ◽  
Process Model ◽  
Design Method ◽  
Solution Space ◽  
The Novel ◽  
Creation Process ◽  
Design Scheme ◽  
Mechanical Products ◽  
Basic Behavior ◽  
The Given

Conceptual design for the mechanical products is the most important and complex phase. Most of the human’s creativity is exhibited in this phase. So many researchers in the world have made researches on its theory and methodology. So far there exists an evident limitation for the modern conceptual design methodology. That is to say, the design scheme obtained form conceptual design is only one solution to the given design problem, which cannot guarantee the creativity and novelty of the design scheme. In order to improve the creativity of conceptual design, the re-creation process model for the intelligent conceptual design is presented in this paper based on function-behavior-structure model. This model expanded the problem’s solution space by degrading the space of behavior and granularity, and describing the behavior space using the more basic behavior. The key of re-creation process model is the transformation of behavior and granularity space. Taking the theory of quotient space as the math description tool, the transformation for the space of behavior and granularity is studied in detail in this paper. At last, an example is given to prove that it is easy to obtain the novel and creative design scheme applying the method presented in this paper.

Function and behavior representation in conceptual mechanical design

2002 ◽  
Vol 16 (5) ◽  
pp. 343-362 ◽  
Author(s):  
Y.-M. DENG
Keyword(s):  
Conceptual Design ◽  
Mechanical Design ◽  
Input Output ◽  
Action Function ◽  
Design Synthesis ◽  
Design Concepts ◽  
Function Decomposition ◽  
Mechanical Products ◽  
Mapping Process ◽  
And Behavior

Conceptual design seeks to deliver design concepts that implement desired functions. Function and behavior are two dominant terms used in the research of this design phase. However, there are still some fundamental ambiguities and confusions over their representation, which have greatly hindered the interchange of research ideas and the development of design synthesis strategies. For conceptual design of mechanical products specifically, this paper attempts to clarify these ambiguities. It classifies function as purpose function and action function and relates them to the different levels of design hierarchy and abstraction. It distinguishes between semantic and syntactic representations of function and behavior and summarizes basic representation schemes. It also proposes an input–output action transformation scheme for semantic function representation and an input–output flow of action scheme for semantic behavior representation. Based on these discoveries, a refined framework is proposed for conceptual mechanical product design, where a function–decomposition–mapping process is elaborated to demonstrate the necessities and usefulness of the presented work.

A Study on the Conceptual Design Method Based on Extension Method

2012 ◽  
Vol 9 (1) ◽  
pp. 861-866
Author(s):  
C. T. Wu ◽  
N. T. Liu ◽  
J. R. Chou ◽  
C. S. Wu
Keyword(s):  
Conceptual Design ◽  
Design Method ◽  
Extension Method

scholarly journals Configuration Study of Electric Helicopters for Urban Air Mobility

Aerospace ◽  
2021 ◽  
Vol 8 (2) ◽  
pp. 54
Author(s):  
Julia A. Cole ◽  
Lauren Rajauski ◽  
Andrew Loughran ◽  
Alexander Karpowicz ◽  
Stefanie Salinger
Keyword(s):  
Conceptual Design ◽  
Urban Areas ◽  
Design Space ◽  
Design Method ◽  
Urban Air ◽  
Main Rotor ◽  
Potential Benefits ◽  
Compound Helicopter ◽  
Configuration Changes

There is currently interest in the design of small electric vertical take-off and landing aircraft to alleviate ground traffic and congestion in major urban areas. To support progress in this area, a conceptual design method for single-main-rotor and lift-augmented compound electric helicopters has been developed. The design method was used to investigate the feasible design space for electric helicopters based on varying mission profiles and technology assumptions. Within the feasible design space, it was found that a crossover boundary exists as a function of cruise distance and hover time where the most efficient configuration changes from a single-main-rotor helicopter to a lift-augmented compound helicopter. In general, for longer cruise distances and shorter hover times, the lift-augmented compound helicopter is the more efficient configuration. An additional study was conducted to investigate the potential benefits of decoupling the main rotor from the tail rotor. This study showed that decoupling the main rotor and tail rotor has the potential to reduce the total mission energy required in all cases, allowing for increases in mission distances and hover times on the order of 5% for a given battery size.

scholarly journals On the formation and stability of fermionic dark matter halos in a cosmological framework

2020 ◽  
Author(s):  
Carlos R Argüelles ◽  
Manuel I Díaz ◽  
Andreas Krut ◽  
Rafael Yunis
Keyword(s):  
Black Hole ◽  
Dark Matter ◽  
Space Distribution ◽  
Coarse Grained ◽  
Dark Matter Halos ◽  
The Core ◽  
The Galaxy ◽  
Gravitating Systems ◽  
The Given ◽  
First Time

Abstract The formation and stability of collisionless self-gravitating systems is a long standing problem, which dates back to the work of D. Lynden-Bell on violent relaxation, and extends to the issue of virialization of dark matter (DM) halos. An important prediction of such a relaxation process is that spherical equilibrium states can be described by a Fermi-Dirac phase-space distribution, when the extremization of a coarse-grained entropy is reached. In the case of DM fermions, the most general solution develops a degenerate compact core surrounded by a diluted halo. As shown recently, the latter is able to explain the galaxy rotation curves while the DM core can mimic the central black hole. A yet open problem is whether this kind of astrophysical core-halo configurations can form at all, and if they remain stable within cosmological timescales. We assess these issues by performing a thermodynamic stability analysis in the microcanonical ensemble for solutions with given particle number at halo virialization in a cosmological framework. For the first time we demonstrate that the above core-halo DM profiles are stable (i.e. maxima of entropy) and extremely long lived. We find the existence of a critical point at the onset of instability of the core-halo solutions, where the fermion-core collapses towards a supermassive black hole. For particle masses in the keV range, the core-collapse can only occur for Mvir ≳ E9M⊙ starting at zvir ≈ 10 in the given cosmological framework. Our results prove that DM halos with a core-halo morphology are a very plausible outcome within nonlinear stages of structure formation.

A New Algorithm to Reduce PAPR in STBC MIMO-OFDM System

2013 ◽  
Vol 760-762 ◽  
pp. 190-193
Author(s):  
Ya Jing Wang ◽  
Ya Zhen Li ◽  
Jing Guan
Keyword(s):  
Ofdm System ◽  
The Core ◽  
Use Of Time ◽  
Time Space ◽  
Core Technology ◽  
Mimo Ofdm ◽  
Papr Performance ◽  
And Inversion ◽  
Development Prospects ◽  
Great Development

MIMO and OFDM technology is the core technology of 4G network, and have great development prospects. The main drawback of MIMO-OFDM system is the high PAPR. This paper is based on Cross-antenna rotation and inversion and Active Constellation Extension. The paper proposed the joint algorithm to reduce PAPR in STBC MIMO-OFDM system. It makes use of time, space and frequency freedom to improve the PAPR performance. The simulation results show that the joint algorithm can effectively reduce the PAPR value and do not increase the bit error rate in STBC MIMO-OFDM system.

Plasma Resource Recovery Technology: Converting Waste to Energy and Valuable Products

2005 ◽  
Author(s):  
Pierre Carabin ◽  
Gillian Holcroft
Keyword(s):  
Carbon Monoxide ◽  
Construction Material ◽  
Resource Recovery ◽  
Waste To Energy ◽  
Small Scale ◽  
Cruise Ship ◽  
Plasma Flame ◽  
Fuel Gas ◽  
The Core ◽  
Core Technology

Plasma Resource Recovery (PRR) is a revolutionary technology that can treat virtually any type of waste by combining gasification with vitrification. Vitrification produces inert slag that can be used as a construction material. Gasification produces a fuel gas containing carbon monoxide (CO) and hydrogen (H2), used for cogeneration of electricity and steam. The plasma fired eductor which is the core technology of the PRR system is presently being used commercially on a cruise ship at a scale of 5 TPD. The capabilities of the PRR technology have been demonstrated in a pilot plant, at a rate of up to 2 TPD of various types of waste. Because of the high intensity of the plasma flame and the reduced amounts of gases produced in a gasification system, compared to traditional combustion systems, the PRR system is typically very compact. As such, the PRR technology opens the door for a decentralized, small scale approach to waste management.

scholarly journals Design of a Hand-Launched Solar-Powered Unmanned Aerial Vehicle (UAV) System for Plateau

2020 ◽  
Vol 10 (4) ◽  
pp. 1300 ◽  
Author(s):  
Xin Zhao ◽  
Zhou Zhou ◽  
Xiaoping Zhu ◽  
An Guo
Keyword(s):  
Low Temperature ◽  
Conceptual Design ◽  
Unmanned Aerial Vehicle ◽  
Design Method ◽  
Structure Design ◽  
Control Law ◽  
Trajectory Tracking Control ◽  
Plateau Area ◽  
Aerial Vehicle ◽  
Solar Powered

This paper describes our work on a small, hand-launched, solar-powered unmanned aerial vehicle (UAV) suitable for low temperatures and high altitudes, which has the perpetual flight potential for conservation missions for rare animals in the plateau area in winter. Firstly, the conceptual design method of a small, solar-powered UAV based on energy balance is proposed, which is suitable for flight in high-altitude and low-temperature area. The solar irradiance model, which can reflect the geographical location and time, was used. Based on the low-temperature discharge test of the battery, a battery weight model considering the influence of low temperature on the battery performance was proposed. Secondly, this paper introduces the detailed design of solar UAV for plateau area, including layout design, structure design, load, and avionics. To increase the proportion of solar cells covered, the ailerons were removed and a rudder was used to control both roll and yaw. Then, the dynamics model of an aileron-free layout UAV was developed, and the differences in maneuverability and stability of aileron-free UAV in plateau and plain areas were analyzed. The control law and trajectory tracking control law were designed for the aileron-free UAV. Finally, the flight test was conducted in Qiangtang, Tibet, at an altitude of 4500 m, China’s first solar-powered UAV to take off and land above 4500 m on the plateau in winter (−30 °C). The test data showed the success of the scheme, validated the conceptual design method and the success of the control system for aileron-free UAV, and analyzed the feasibility of perpetual flight carrying different loads according to the flight energy consumption data.

scholarly journals Mind mapping as a tool of teaching English vocabulary at transport university

2021 ◽  
Vol 295 ◽  
pp. 05021
Author(s):  
Oksana Marunevich ◽  
Elmira Shefieva ◽  
Olga Bessarabova
Keyword(s):  
Educational Process ◽  
Control Group ◽  
Teaching English ◽  
Mind Mapping ◽  
New Words ◽  
The Core ◽  
Mind Maps ◽  
The Given ◽  
Core Problem ◽  
Experimental Group

The core problem of teaching English as a second language at transport university is students’ poor knowledge of vocabulary. Current solutions to the given problem such as providing word explanations and repetitive practices are ineffective. We strongly believe that the mindmapping technique proposed by Tony Buzan as a note-taking method is a novel, yet an extremely potent tool that aids students in enlarging their professional word stock by associating new vocabulary to their existing knowledge using colors, images, symbols, etc. As might have been expected, the findings of our study point towards the idea that the strong visual appeal of mind maps created by easy-to-use software boosted the educational process and helped students of the experimental group memorize more new words in contrast to students of the control group.

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