Methods of Calculation of Floodlighting Utilisation Factor at the Design Stage

2018 ◽  
pp. 144-152 ◽  
Author(s):  
Krzysztof Skarżyński
Keyword(s):  
Luminous Flux ◽  
General Analysis ◽  
Design Stage ◽  
Utilization Factor ◽  
Methods Of Calculation ◽  
Flux Loss

The main aim of this work is to present different methods of calculation of these new parameters: floodlighting utilization factor, useful luminous flux, loss of luminous flux and coefficient of floodlighting utilization factor. Each method is carefully described. There is also a general analysis of the assumptions and restrictions used in the calculations. The results of the calculations are presented and broadly discussed with reference to a very simple and a more complex floodlighting design. It was found that these parameters are very helpful and convenient in the assessment of the quality of floodlighting at the design level.

scholarly journals Simulation of rod vibrations process with an independent pendular suspension and vertical stabilization system

2018 ◽  
Vol 56 (4) ◽  
pp. 469-480
Author(s):  
I. S. Kruk ◽  
A. A. Tiunchik ◽  
V. Romanyuk
Keyword(s):  
Technological Process ◽  
Initial Conditions ◽  
Vertical Movement ◽  
Design Stage ◽  
Geometrical Parameters ◽  
Stabilization System ◽  
Special Approach ◽  
Rod Structures ◽  
Design And Testing

Continuous improvement of field sprayer design aimed at performance increase by increasing the working width, requires a special approach to ensure reliability of the supporting rod structure and quality of technological process. The question of rod vibrations, which arise when the driving systems copy field rough surface and abrupt changes in speed of the unit, remains topical. At the design stage of supporting structures of the rods, special attention is paid to the substantiation of its geometrical parameters in the longitudinal and transverse sections; studies of changes in the characteristics of vertical and horizontal vibrations, taking into account the method of the rod hanging and the system used for its stabilization. This allows to ensure the reliability of the rod design and the required quality of the technological process. The article proposes construction of the rod independent pendulum suspension on the sprayer frame and its stabilization system based on the use of damping elements. The analytical studies sequence system was developed for rod vibrations analysis, depending on initial conditions, parameters and characteristics of the used damping elements, under which they are effectively damped. It is shown that at certain numerical values of the geometrical parameters of the rod, the suspension and vibrations damping methods, not only the numerical values of the functions are changed, but also the functions themselves that describe the process of the rod's vertical movement, including cases of resonance. The obtained theoretical results can be used for design and testing of machines with rod working units and allow, at design stages, to simulate the process of movement of various rod structures from external excitatory forces, and to determine patterns of changes in the characteristics of damped vibrations using different damping elements and their installation parameters.

A Novel Methodology to Manage Uncertainty for Multidisciplinary Design and Optimization in Conceptual Design

2008 ◽  
Vol 44-46 ◽  
pp. 225-232 ◽  
Author(s):  
Xin Yu Shao ◽  
Xue Zheng Chu ◽  
Liang Gao ◽  
Hao Bo Qiu
Keyword(s):  
Conceptual Design ◽  
Probabilistic Method ◽  
Kriging Model ◽  
Design Stage ◽  
Design And Optimization ◽  
Rough Sets Theory ◽  
Innovative Methodology ◽  
Traditional Approaches ◽  
Sets Theory

Uncertainty in design and simulation affects the quality of product directly during the process of MDO, which should be considered to help designers to make the design decisions, especially at conceptual design stage. In traditional approaches, this uncertainty is ignored in the hope that it is not significant to the decision making. In this investigation, firstly, three main uncertainties in MDO of conceptual design are pointed out and carefully analyzed. Then, an innovative methodology integrating extract knowledge and probabilistic method to manage these uncertainties is presented. Considering practical application and eliminating the uncertainty in configuration, we propose a promising method combining Fuzzy c-means algorithm (FCM) and Rough Sets theory (RST) to deduce the configuration rule. Furthermore, probabilistic kriging model is utilized as an approximation model to reduce global computational expense of complex product. Sensitivity analysis (SA) is used to reduce uncertainty of inputs of simulation, and mean square error (MSE) is employed to assess model error to reduce model uncertainty. Finally, the validity and necessity of this methodology are demonstrated through the conceptual design of bulk carrier.

scholarly journals The influence of power electronic converter passive filter parameters for flicker in LED lighting

2018 ◽  
Vol 21 ◽  
pp. 00020
Author(s):  
Dariusz Sobczynski
Keyword(s):  
Power Systems ◽  
Supply Voltage ◽  
Current Source ◽  
Luminous Flux ◽  
Light Sources ◽  
Light Emitting ◽  
Current Voltage ◽  
Passive Filters ◽  
The Stability

The light emitting diodes (LEDs) are ever more used, and their price is getting lower year on year. Although, exchanging traditional light sources for the LED lamps does not seem to be complicated, we need to remember to maintaining high–quality of light. One of the aspects we should be worry about is a light’s flickering. Due to the shape of the current–voltage characteristics of the LED diode and their dependence on temperature, the value of the luminous flux – but also the lifetime – depends to a large extent on the stability of the supply voltage. Therefore, correct power system should be a thermally stable current source. Unfortunately, the simple power systems, equipped with passive filters are often used as cheap commercial solutions. In those types of systems stability of the output voltage is heavily dependent on the load conditions. Passive filters – usually consisting of coils and capacitors – are placed in the output circuit. This paper presents research carried out to show of filter capacitance influence on flickering phenomenon, and practical light’s flickering measuring technique for the LED lamps.

scholarly journals Taking account of test takers’ personal characteristics in language test development process

2019 ◽  
Vol 70 ◽  
pp. 04002 ◽  
Author(s):  
Svetlana Baluyan
Keyword(s):  
Test Performance ◽  
Development Process ◽  
Personal Characteristics ◽  
Individual Characteristics ◽  
Design Stage ◽  
Language Test ◽  
Specific Knowledge ◽  
Emotional Component ◽  
Overall Effectiveness

The article presents the results of a study aimed at solving the problem of improving the quality of a language test. It was found that taking into account test takers’ individual characteristics that may affect their test performance, namely their personal characteristics, general and specific knowledge, language ability level and the emotional component at the design stage allows to increase reliability, interactiveness, impact, authenticity and even practicality of the test, which, in turn, contribute in its overall effectiveness.

CAD-Based Tolerance Analysis in Preliminary Design Stages Enabling Early Tolerance Evaluation

2018 ◽  
Author(s):  
Stefan Goetz ◽  
Benjamin Schleich ◽  
Sandro Wartzack
Keyword(s):  
Tolerance Analysis ◽  
Design Stage ◽  
Preliminary Design ◽  
Design Changes ◽  
Preliminary Design Stage ◽  
Geometric Deviations ◽  
Set Up ◽  
Quality Of Products ◽  
Analysis Models

Associated with manufacturing and assembly processes, inevitable geometric deviations have a decisive influence on the function and quality of products. Therefore, their consideration and management are important tasks in product development. Moreover, to meet the demand for short development times, the front-loading of design processes is indispensable. This requires early tolerance analyses evaluating the effect of deviations in a design stage, where the product’s geometry has not yet been finally defined. Since such an early tolerance consideration allows quick and economic design changes seeking for robust designs, it is advisable that the design engineer, who is entirely familiar with the design, should take this step. For this purpose, this paper presents an easy-to-use CAD-based tolerance analysis method for skeleton models. The relevant part deviations are represented by varying geometric dimensions with externally driven family tables. The approach comprises the strength of vector-based methods but does not require an expensive set-up of tolerance analysis models. Particularly, the novelty of this method lies in the CAD-internal sampling-based tolerance analysis of simple geometries without the use of expensive CAT software. This enables designers to evaluate the effect of tolerances already at the preliminary design stage. Using a case study, the presented approach is compared with the conventional vector-based tolerance analysis.

1.2 Computers and Their Potential: Software

1981 ◽  
Vol 5 ◽  
pp. 5-8
Author(s):  
Pamela A. Geisler ◽  
J. France
Keyword(s):  
High Reliability ◽  
Computer Hardware ◽  
Design Stage ◽  
Final Phase ◽  
Implementation Phase ◽  
Storage Media ◽  
Systems Software ◽  
And Performance ◽  
High Level

At the present time, with the high reliability and performance of computer hardware, computer systems applied in any field must be judged more by the quality of the software provided. Thus it is highly relevant in an investigation of the use of computers in a field such as animal production, to concentrate on aspects of the software.Software provides the computer with the ability to obey instructions and to do as the user wishes. However, before arriving at these ‘machine instructions’ a number of steps have to be covered. First, it is essential to design the software — that is, to establish the requirements to be achieved on the computer. This design stage is followed by the implementation phase, in which the requirements as stated in English are transformed into such instructions as the machine can read and obey. The final phase is testing, in which it must be determined whether the requirements have been met, and to modify the design and iterate until the performance is satisfactory.Software in general can be divided into three classes — systems, utility and applications software. The systems software drives the machine and its associated peripherals such as a VDU and printer. The systems software also includes a file system for organization of the data on the relevant storage media (floppy disks, cartridges, magnetic tape). Also considered part of the systems software are the assembler, interpreters and compilers for high level languages such as BASIC and FORTRAN and for programming aids such as DEBUGGERS. Systems software is normally supplied with the computer and needs to be evaluated along with the hardware by any prospective purchaser of a computer system.

scholarly journals Mathematical model of the turning process using vibration impact on the cutting tool

2020 ◽  
Author(s):  
А.Н. Синько ◽  
Т.Ю. Никонова ◽  
В.В. Юрченко ◽  
А.К. Матешов ◽  
И.А. Марченко
Keyword(s):  
Cutting Tool ◽  
Block Diagram ◽  
Numerical Data ◽  
Optimal Level ◽  
Variable Cross Section ◽  
Cutting Edge ◽  
Design Stage ◽  
Variable Cross ◽  
Turning Process

В статье авторами проведено математическое моделирование процесса точения с использованием волнового воздействия на режущий инструмент. Установлены зависимости между видом образующейся стружки и качеством обработанной поверхности от интенсивности вводимых в зону резания колебаний, а также численные данные параметров режима резания. Авторами установлено, что существует определенный оптимальный уровень колебаний, при котором наблюдается максимальная стойкость инструмента, повышение производительности и улучшение качества обработанной поверхности. Данные зависимости позволяют разработать структурную схему и последовательность проектирования операций с применением вибрационного точения. Для данного процесса авторами установлен оптимальный уровень интенсивности колебаний применительно к инструментам, оснащенным твердым сплавом, при обработке конструкционных и высоколегированных материалов. Практической значимостью работы является получение математических моделей о процессе точения с использованием вибрационного воздействия на режущий инструмент, на основании которых были получены данные и созданы прототипы режущих инструментов для применения в аппаратах вибрационного точения. Основной методикой получения математических данных о вибрационном воздействии на режущий инструмент является обобщение многочисленных экспериментальных данных, а также проведение исследования с помощью программ твердотельного проектирования. В результате исследований получены параметрические уравнения, позволяющие на стадии проектирования прогнозировать и описывать траекторию движения режущей кромки резца при вибрационном воздействии на режущий инструмент. Получены графические схемы траектории перемещения режущей кромки инструмента, демонстрирующие переменное сечение срезаемого слоя при вибрационном воздействии на режущий инструмент. The purpose of this work is to obtain mathematical data about the turning process using vibration effects on the cutting tool. The main method for obtaining mathematical data on the vibration effect on the cutting tool is to generalize numerous experimental data, as well as conducting research using solid-state design programs. In the course of the work, mathematical modeling of the turning process was carried out using the wave effect on the cutting tool. The dependences between the type of chips formed and the quality of the treated surface on the intensity of vibrations introduced into the cutting zone, as well as numerical data on the parameters of the cutting mode, are established. It has been established that there is a certain optimal level of oscillation at which the maximum tool life, increased productivity and improved quality of the treated surface are observed. These dependencies allow you to develop a block diagram and design sequence for the vibration turning operation. For vibration turning, the optimal level of vibration intensity is set for tools equipped with a hard alloy when processing structural and high-alloy materials. The obtained parametric equations make it possible to predict and describe the trajectory of the cutting edge of the cutter at the design stage when the cutting tool is vibrated. Graphic diagrams of the trajectory of the cutting edge of the cutting tool are obtained, showing a variable cross-section of the cut layer under vibration action on the cutting tool. In this work, the regularities of vibration turning during turning are shown. On the basis of which practical data were obtained and prototypes of cutting tools for use in vibration turning devices were created.

scholarly journals EVALUATION OF FLOOR COVERINGS FROM THE ECOLOGICAL AND ECONOMIC ASPECT IN THE DESIGN STAGE

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Marina Nikolić Topalović ◽  
Milenko Stanković
Keyword(s):  
Life Cycle ◽  
Human Health ◽  
Software Package ◽  
The United States ◽  
Economic Aspect ◽  
Design Stage ◽  
Construction Products ◽  
Floor Coverings ◽  
The Impact

Measures to reduce the impact of the construction sector on the environment and human health need to be taken at the design stage of the facility and evaluate building materials and products from an ecological and economic aspect. For the research needs, a comparison of floor coverings at the design stage was made to assess their impact during the life cycle. The research uses the life cycle analysis (LCA), a methodology that is the basis for analyzing the impacts during the life cycle of the analyzed construction products. The research covers the life cycle stages from A1 to C4, according to the standard ISO EN 15978: 2011. The software package BEES, the National Institute of Standardization and Technology (NIST), the United States of America is used for the turn. Five types of floor coverings were analyzed, from the aspect of their impact on the environment and human health, but also from the economic point of view. The research has shown that in the design phase, using software packages can be managed with the quality of the environment, and the project design, and hence the quality of the facility. The research also points to the need for a national software package that can analyze construction products and materials. Their application would improve the national construction industry and favored materials that are environmentally and economically acceptable in relation to materials with unfavorable effects on the environment and human health.

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