scholarly journals PENGARUH PANJANG BENTANG TERHADAP UKURAN PENAMPANG OPTIMUM BETON PRATEGANG PADA BALOK SEDERHANA DENGAN MENGGUNAKAN ALGORITMA GENETIKA

2018 ◽  
Vol 7 (1) ◽  
pp. 16-25
Author(s):  
Alfian Wiranata Zebua
Keyword(s):  
Optimum Design ◽  
Low Cost ◽  
Optimization Procedure ◽  
Service Condition ◽  
Beam Width ◽  
Beam Length ◽  
Limit Values ◽  
Optimization Result ◽  
Prestressing Force ◽  
Fitness Value

Abstract: Structural design philosophy expected to be low cost and safe at once. At prestressed concrete structure, concrete allowable stress for bending structural component have to fullfill limit values on tranfer and service condition. Prestressed force determined using moment coeffiecient β method based on allwoable stress. At this structure, to achieve optimum design is not an easy task due to interaction between dimension size and prestressing force value. To determine optimum design criteria, genetics algorithms as one of optimum design method has been used in this paper. Genetics algorithm is a method to find the best solution using organism genetics process based on Darwin theory which solutions with the best fitness value that could be survive as the optimization result. Fitness value is minimum construction cost. Optimization process using genetics algorithm has been worked with computer software assitance Matlab. Simpe beam has been considered as numerical example. Optimization result is optimum design of dimension size and prestressing force. Optimization procedure with beam length (L) 10 m result are beam width (b) 0,40 m, beam height (h) 0,47 m, prestressing force (Fi) value 1344 KN and bulding cost total Rp. 16.651.000,-. Next optimization procedure has been done using different beam length. From this study, the interaction between beam length to optimum dimension size and minimum building cost has been achieved.Keywords : beam length, genetics algoritm, optimum sizing, prestressed concreteAbstrak: Filosofi perencanaan struktur diharapkan ekonomis sekaligus aman. Pada struktur beton prategang, tegangan ijin beton untuk komponen struktur lentur harus memenuhi nilai batas pada saat transfer dan beban layan. Gaya prategang ditentukan dengan menggunakan metode koefisien momen β yang didasarkan pada tegangan ijin. Pada struktur ini, penentuan desain optimum tidak mudah karena adanya keterkaitan antara ukuran penampang dengan besaran gaya prategang yang dibutuhkan. Untuk memperoleh kriteria desain yang optimum digunakan metode optimasi dengan menggunakan algoritma genetika. Algoritma genetika merupakan metode pencarian sesuai dengan proses genetika  organisme berdasarkan teori evolusi Darwin, dimana solusi dengan nilai fitness (tujuan) yang tinggi yang mampu bertahan sebagai hasil dari proses optimasi. Nilai fitness (tujuan) adalah memperoleh total harga konstruksi yang paling rendah. Proses optimasi dengan algoritma genetika dikerjakan dengan bantuan software komputer Matlab. Untuk melakukan optimasi digunakan algoritma genetika real. Jenis struktur yang ditinjau adalah balok sederhana. Dari hasil optimasi dengan berbagai panjang bentang diperoleh dimensi balok dan nilai gaya prategang yang optimum. Proses optimasi dengan panjang bentang (L) 10 m, diperoleh lebar balok (b) 0,40 m,  tinggi balok (h) 0,47 m, nilai gaya prategang (Fi) sebesar 1344 KN dengan total harga Rp. 16.651.000,-. Proses optimasi selanjutnya dilakukan dengan panjang bentang balok yang bervariasi. Dari hasil penelitian diperoleh hubungan antara panjang bentang balok dengan ukuran penampang optimum serta harga total struktur yang paling rendah.Kata kunci : algoritma genetika, beton prategang, panjang bentang, ukuran penampang optimum

An Analysis of Filament Overwound Toroidal Pressure Vessels and Optimum Design of Such Structures

2002 ◽  
Vol 124 (2) ◽  
pp. 215-222 ◽  
Author(s):  
Shuguang Li ◽  
John Cook
Keyword(s):  
Optimum Design ◽  
Equivalent Stress ◽  
Mechanical Damage ◽  
Stress Rupture ◽  
Optimization Procedure ◽  
Pressure Vessels ◽  
Thickness Variation ◽  
Von Mises Equivalent Stress ◽  
Metal Liner ◽  
Von Mises

This paper is concerned with the membrane shell analysis of filament overwound toroidal pressure vessels and optimum design of such pressure vessels using the results of the analysis by means of mathematical nonlinear programming. The nature of the coupling between overwind and linear has been considered based on two extreme idealizations. In the first, the overwind is rigidly coupled with the liner, so that the two deform together in the meridional direction as the vessel dilates. In the second, the overwind is free to slide relative to the linear, but the overall elongations of the two around a meridian are identical. Optimized designs with the two idealizations show only minor differences, and it is concluded that either approximation is satisfactory for the purposes of vessel design. Aspects taken into account are the intrinsic overwind thickness variation arising from the winding process and the effects of fiber pre-tension. Pre-tension can be used not only to defer the onset of yielding, but also to achieve a favorable in-plane stress ratio which minimizes the von Mises equivalent stress in the metal liner. Aramid fibers are the most appropriate fibers to be used for the overwind in this type of application. The quantity of fiber required is determined by both its short-term strength and its long-term stress rupture characteristics. An optimization procedure for the design of such vessels, taking all these factors into account, has been established. The stress distributions in the vessels designed in this way have been examined and discussed through the examples. A design which gives due consideration of possible mechanical damage to the surface of the overwind has also been addressed.

Laser forming of LTCC Ceramics for Hot-Plate Gas Sensors

2005 ◽  
Vol 2 (1) ◽  
pp. 14-18 ◽  
Author(s):  
Jaroslaw Kita ◽  
Frank Rettig ◽  
Ralf Moos ◽  
Karl-Heinz Drüe ◽  
Heiko Thust
Keyword(s):  
Power Consumption ◽  
Gas Sensors ◽  
Low Cost ◽  
Sensor Arrays ◽  
Beam Width ◽  
Laser Forming ◽  
Hot Plate ◽  
Small Series ◽  
Plate Design ◽  
Future Work

Hot-plate LTCC gas sensors combine advantages of silicon structures (low power consumption) and typical ceramics gas sensors (stability and reliability). Such elements can be integrated in MEMS packages as well as in ceramic sensor arrays. Moreover, they can be produced in small series with relatively low cost. One important key in hot-plate design are properly formed beams. This paper presents possibilities and problems related to laser forming of LTCC ceramics for hot-plate gas sensors. Influence of beam width on power consumption and temperature distribution is discussed. Possibilities to achieve beam width as narrow as possible are practically tested by laser cutting. Obtained results are very promising for future work and for possible application of LTCC ceramics in such type of gas sensors.

Optimum Design of Multi-Layered Vessels

2005 ◽  
Author(s):  
Hamid Jahed ◽  
Behrooz Farshi ◽  
Morvarid Karimi
Keyword(s):  
High Pressure ◽  
Optimum Design ◽  
Load Capacity ◽  
Crack Depth ◽  
Optimization Procedure ◽  
Stress Constraints ◽  
Pressure Vessels ◽  
Design Variables ◽  
Significant Life ◽  
Shrink Fit

Multi-layered pressure vessels are widely used in the field of high pressure technology. To enhance their load bearing capacity and life, different beneficial processes such as shrink-fit and autofrettage are usually employed. Shrink-fit process, increases load capacity but maximum interference is generally limited. Autofrettage, makes steep stress gradients moving away from bore but Bauschinger effect limits maximum feasible compression level. A combination of both, can conceivably give better stress distribution in layered vessels. The optimum design of a three-layer vessel for maximum life expectancy has been considered here, under the combined effects of autofrettage and shrink-fit. The numerical optimization procedure known as the Simplex search method is employed to get the optimum design. The layer thicknesses, shrink-fit pressures, and autofrettage percentages are treated as design variables. Under stress constraints, the operational sequences of the above processes, for assembly of the layered vessel have also been formulated so as to lead to best results. The fatigue life consideration is based on ASME code and standard for high pressure vessel technology defining the allowable final crack depth in multi-layered vessels. The proposed procedure is carried out on a number of examples. The results show that significant life enhancement can be achieved using the optimization procedure with proper combination of operations.

scholarly journals The optimization procedure in the tax system, the processing organizations

2019 ◽  
Vol 81 (1) ◽  
pp. 357-365
Author(s):  
A. I. Khоrеv ◽  
G. V. Belyaeva ◽  
A. N. Polozova ◽  
R. V. Nuzhdin
Keyword(s):  
Low Cost ◽  
Optimization Procedure ◽  
Economic Benefits ◽  
Tax Burden ◽  
Tax System ◽  
Tax Legislation ◽  
Tax Management ◽  
Tax Benefits ◽  
Processing Organizations ◽  
Tax Payments

An effective process of tax management of processing organizations is the optimization of the tax system, which provides an increase in the mass of tax benefits of taxpayers. For food processing organizations, optimization procedures are of particular importance due to the high and ever-increasing tax burden on economic activity. It has been established that over the past eleven years, the tax burden of processing organizations increased 2.1 times, outpacing its growth rates in organizations of other types of activity by 2.3 times. These relationships are additional arguments in favor of the need to develop optimization procedures, taking into account the specific features of organizations of food production. Carrying out optimization procedures by system and deductive methods provides for the development of a program of relevant measures. As objects of program activities, it is advisable to choose those for which the current tax legislation provides for the greatest number of benefits, and which will bring tangible economic benefits to organizations. The main objects are taxes: income, property, VAT, personal income tax, since each category of these has optimization opportunities for calculating the tax base and reducing the mass of tax payments to the budgets of the respective levels. A brief, meaningful title has been formulated for each program event, the essence of which directly affects the magnitude of such elements of the taxation system as the taxable base, tax payment terms, organizational and methodological parameters for tax calculation, accounting registers of accounting tax policy and others. Detailed explanations are given on individual optimization measures with an indication of regulatory legal acts that allow using a particular benefit or opportunity in taxation practice, and also lists the basic conditions for the application of the recommendations made. Particular attention is paid to the rules of registration of primary documents, as basic accounting units that change during the implementation of specific recommendations. The introduction of the recommended program of optimization procedures into the practice of tax management has a real prospect due to the low-cost financial resources for their implementation, but it will significantly increase the level of tax solvency of the processing organizations.

Assessment of heterogenity of air pollution within an urban canopy

2020 ◽  
Author(s):  
Vivien Voss ◽  
K. Heinke Schlünzen ◽  
David Grawe
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Citizen Science ◽  
Urban Areas ◽  
Hot Spot ◽  
Low Cost ◽  
Urban Canopy ◽  
Limit Values ◽  
Data Standard ◽  
The City

<p>Air pollution is an important topic within urban areas.  Limit values as given in the European Guidelines are introduced to reduce negative effects on humans and vegetation.  Exceedances of the limit values are to be assessed using measurements.  In case of found exceedances of the limit values, the local authorities need to act to reduce pollution levels. Highest values are found for several pollutants (NOx, NO2, particles) within densely build-up urban areas with traffic emissions being the major source and dispersion being very much impacted by the urban structures.  The quality assured measuring network used by the authorities is often too coarse to determine the heterogeneity in the concentration field. Low cost sample devices as employed in several citizen science projects might help to overcome the data sparsity. Volunteers measure the air quality at many sites, contribute to the measurement networks and provide the data on the web. However, the questions arising are: a) Are these data of sufficient high quality to provide results comparable to those of the quality assured networks? b) Is the network density sufficient to determine concentration patterns within the urban canopy layer? <br>One-year data from a citizen science network, which measures particulate matter (PM10, PM2.5) were compared to measurements provided by the local environmental agency, using two hot-spot areas in the city of Hamburg as an example. To determine how well the measurements agree with each other, a regression analyses was performed dependent on seasonal and diurnal cycles. Additionally, model simulations with the microscale obstacle resolving model MITRAS were performed for two characteristic building structures and different meteorological situations. The model results were used to determine local hot spots as well as areas where measurements might represent the concentration of particles for the urban quarter. The low cost sensor measurements show a general agreement to the city’s measurements, however, the values per sensor differ. Moreover, the measurements of the low-cost-sensor show an unrealistic dependence on relative humidity, resulting in over- or underestimations in certain cases. The model results clearly show that only a few sites allow measurements to be representative for a city quarter. The measurements of the citizen science project can provide a good overview about the tendencies of the air quality, but are currently not of sufficient quality to provide measurements calling for legal action.</p><p>The model results were used for the project AtMoDat. AtMoDat is an attempt to create a data standard for obstacle resolving models based on the existing Climate and Forecast (CF) conventions. A web-based survey is developed to get information on the requirements for the data standard. The next step is to extend the collection of model characteristics and eventually to provide a generic scheme.</p><p><strong>Acknowledgements</strong><br>This work contributes to project “AtMoDat” funded by the Federal Ministry of Education and Research under the funding number 16QK02C. Responsibility for the content of this publication lies with the authors.</p>

Research on the Dynamic Response of Capacitive RF-MEMS Switch

2013 ◽  
Vol 791-793 ◽  
pp. 1909-1912 ◽  
Author(s):  
Ming Xin Song ◽  
Rui Wu
Keyword(s):  
Differential Equation ◽  
Dynamic Response ◽  
Response Time ◽  
Rf Mems ◽  
Beam Width ◽  
Beam Length ◽  
Rf Mems Switch ◽  
Mems Switch ◽  
Beam Thickness ◽  
Simulation Results

Dynamic response time is an important performance parameter for capacitive RF-MEMS switch. This paper establishes a differential equation, in order to analyse the influencing factors of dynamic response time. The simulation results show that pulling-down time can reach 7.5μs when beam length equals to 200μm, beam width equals to 30μm, beam thickness equals to 1μm, beam material adopts Al and dielectric layer selects Si3N4.

Optimum Design of the 3Z-II Planet Drive Based on Matlab

2011 ◽  
Vol 86 ◽  
pp. 104-107
Author(s):  
Qi Lin Huang ◽  
Yong Wang ◽  
Mao Lin Xu ◽  
Jun Gang Wang ◽  
Zhi Gang Luo
Keyword(s):  
Nonlinear Optimization ◽  
Optimum Design ◽  
Design Theory ◽  
Optimization Result ◽  
Optimization Function

According to the design theory of 3Z-II planet drive, this paper firstly design a transmission plan of a given example，then optimize the transmission plan by using the nonlinear optimization function ‘fmincon’ of MATLAB. Finally, this paper verifies the optimization result.

scholarly journals Design and Analysis of Efficient H-Shaped Multiband Antenna with DGS for Wireless Applications

2020 ◽  
Vol 9 (5) ◽  
pp. 2156-2157
Keyword(s):  
Patch Antenna ◽  
Low Cost ◽  
Impedance Matching ◽  
Ground Plane ◽  
Beam Width ◽  
Split Ring Resonator ◽  
Simulation Software ◽  
Defected Ground Structure ◽  
Multiband Antenna ◽  
Current Path

An efficient H-shaped micro strip multiband antenna is constructed and simulated with slot structure of Split Ring Resonator (SRR) in a ground plane as Defected Ground Structure (DGS) for high frequency applications is proposed. Micro Strip patch antenna is mostly preferred because of its very good radiation properties. Also it is the light weight and low cost device so its usage is very high and its fabrication method is very easy. DGS is used to alter the current path in the ground part of the patch antenna by making this it provides multiband support. The H shape patch antenna with the proper ground plane is normally chosen for increasing the bandwidth of the antenna by providing impedance matching and reduce loss. This type of antenna mostly used in where small size and broad beam width are required. In the simulation VSWR, radiation pattern, gain, return loss were measured using simulation software HFSS

scholarly journals A Cross-Joint Vivaldi Antenna Pair for Dual-Pol and Broadband Testing Capabilities

2021 ◽  
Vol 21 (3) ◽  
pp. 201-209
Author(s):  
Gwang-Hun Jeon ◽  
Philip Ayiku Dzagbletey ◽  
Jae-Young Chung
Keyword(s):  
Wireless Communication ◽  
Low Cost ◽  
Impedance Matching ◽  
Beam Width ◽  
Communication Devices ◽  
Operating Bandwidth ◽  
Vivaldi Antenna ◽  
Increasing Demand ◽  
Half Power ◽  
Vivaldi Antennas

The non-standalone 5G antenna wireless communication standard and devices operating under Wi-Fi 5, 6, and 6E operate at the 3 GHz frequency bands and above. With the increasing demand for these devices and technologies, it is crucial to test them rapidly and economically for commercial usage. This paper presents a dual-polarized Vivaldi antenna for the over-the-air (OTA) measurement of wireless communication devices used in the 3–7 GHz band. The dual-polarization performance is realized by vertically intersecting two planar Vivaldi antennas and soldering them at the back end. A three-step 1/4 wavelength balun is applied to the input for the wideband impedance matching of the antenna, which is attached to a Teflon holder for easy mounting. It has excellent performance and is designed to be manufactured at low cost. The fabricated antenna was tested in an anechoic chamber and showed S11 less than -10 dB from 2.63–7.15 GH, and a realized gain of more than 5 dBi from 3 GHz and above. A measured half-power beam width of more than 60° was realized with symmetric E/H-plane. Much of the required symmetry was achieved with the designed Teflon holder. The antenna has a measured cross-polarization discrimination of better than 15 dB across the entire operating bandwidth.

High-performance MIMO imaging radar with hybrid transmit and receive arrays

2016 ◽  
Vol 8 (4-5) ◽  
pp. 807-813
Author(s):  
M. Nhat Pham ◽  
Arne F. Jacob
Keyword(s):  
High Performance ◽  
Low Cost ◽  
Multiple Input Multiple Output ◽  
Optimization Procedure ◽  
Computational Effort ◽  
High Angular Resolution ◽  
Multiple Signal Classification ◽  
Receiver Array ◽  
Multiple Input ◽  
Input Multiple Output

In this study, a sparse multiple-input multiple-output radar system with difference co-array processing is presented. It consists of two non-uniform transmitter arrays in split configuration and a symmetrical hybrid receiver array. A combination of a periodically thinned array and two non-uniform sub-arrays is used to construct the receiver structure. A low-cost three-step optimization procedure is proposed to synthesize the array arrangement with system constraints. In addition, a combination of fast Fourier transform (FFT) and MUltiple SIgnal Classification (MUSIC) techniques is applied for a range/direction-of-arrival estimation with low computational effort. High angular resolution is achieved in the MUSIC spectrum by implementing a difference co-array concept together with spatial smoothing. A thinning rate in excess of 95% is demonstrated. Lastly, the performance of the proposed system is validated by measurements of point scatterers and extended objects.

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