Currently, the government is trying to improve road infrastructure in the form of tolls and bridges. In its construction design, the general bridge age is planned to have a life span of 100 years for large bridges and...
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ISBN:
(数字)9781728130835
ISBN:
(纸本)9781728130842
Currently, the government is trying to improve road infrastructure in the form of tolls and bridges. In its construction design, the general bridge age is planned to have a life span of 100 years for large bridges and 50 years as the lifespan limit [1]. Over time the bridge will experience changes caused by movement from nature, bridge loads, bridge construction structures, excessive vibration, and so on [1]. One of the causes of a bridge collapse is a load that exceeds the capacity [2]. For example, the case of the ring bridge in Tuban district collapsed, because the vehicle load exceeded the bridge's capacity. Regarding the case of a bridge collapse in Tuban, it inspired the idea to collect, consider and maintain every bridge in Indonesia. If there is a bridge that fixes the collapse, repair activities can be carried out in Indonesia. In this research, a design algorithm was made, in which the compilation of devices mounted by the bridge so as not to exceed the maximum bridge load capacity. Vehicles entering the bridge have been indexed by several variables within 24 hours. Some of these variables are time, vehicle identity consisting of the license plate number, type of vehicle, vehicle weight and index. design a bridge monitoring system and Internet-based (IoT) bridge monitoring algorithm. The truth of the algorithm, a simulation program was created using a visual studio, a database using MySQL and a website over base application. But in designing this algorithm, analysis is needed in determining the number of accelerometer sensors. The purpose of this algorithm system is bridge capability so that the weight of the incoming vehicle is not much or exceeds the bridge's capability limit. The validation of the design of this algorithm is to compare the workings of the standard algorithm. The results of this study are the creation of an algorithm for the Internet of Things (IoT) based monitoring and control systems that can provide information about bridges in real-t
Passive heat transfer enhancement technique, which includes modification of surfaces by various shapes and structures, has been a topic of research during the last decade. The helical microfin tubes, which are deemed ...
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Passive heat transfer enhancement technique, which includes modification of surfaces by various shapes and structures, has been a topic of research during the last decade. The helical microfin tubes, which are deemed promising in improvements of heat transfer, are often implemented in the context of flow condensation. While research regarding their impact on the two-phase flow of refrigerants is accruing, a systematic assessment is required to ensure their promised claims to increase the efficacy of thermal systems. To further expand the database within the literature, two performance criteria, Performance Index (PI) and Penalty Factor (PF), are evaluated for a database comprised of 1192 data during flow condensation of low global warming potential HydroFluoroOlefins (HFOs) inside microfin tubes ranging from 3 to 7 mm outer diameter (OD). The tube of 5 mm OD demonstrated the highest efficacy by the method of PI, while also demonstrating undesirable high PF values. In microfin tubes, despite enhanced heat transfer due to augmentation of turbulence and shear-stress forces, higher frictional pressure drops could nullify the positive effects depending on the circumstances. In a shell and tube condenser with condensation on the tube side, for fixed input and output temperatures on the coolant-side, the pressure drops could cause a noticeable drop in logarithmic mean temperature difference (LMTD). Therefore, an optimal design mass flux must exist to maximize heat transfer coefficients while avoiding adverse effects on LMTD. In some cases, due to lower frictional pressure losses for a smooth tube, it is better to avoid using a microfin structure all together. The article proposes a design procedure to correctly identify and assess the performance by conducting a preliminary simulation of a condenser.
This paper introduces a process for designing a bearing that satisfies both rotordynamic stability and bearing performance using dimensionless bearing data. The dimensionless data of the tilting-pad journal bearing, c...
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This paper introduces a process for designing a bearing that satisfies both rotordynamic stability and bearing performance using dimensionless bearing data. The dimensionless data of the tilting-pad journal bearing, calculated using a numerical model, is dimensioned considering thermal effects through a heat balance model. The dimensionless data is generated by considering variables such as the number of pads, preload, length-diameter ratio and load direction. Using the dimensioned static characteristics, the minimum film thickness and maximum operating temperature of the bearing are calculated. The dynamic characteristics of the bearing are applied to a rotordynamic model, and stability is compared using indicators such as separation margin, maximum vibration amplitude and amplification factor in rotor-dynamic stability analysis. To consider various design parameters, a bearing for an actual shaft system model was designed using the multi-grid method, and the influence of design variables was investigated.
A new protocol called the simple tone sense (STS) protocol is designed for multihop packet radio networks (PRN's) with multiple directional antennas stations. The protocol can minimize transmission interference by...
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A new protocol called the simple tone sense (STS) protocol is designed for multihop packet radio networks (PRN's) with multiple directional antennas stations. The protocol can minimize transmission interference by using a group of tones to identify the active neighbors. A variation of the STS protocol called the variable power tone sense (VPTS) protocol is also designed to further reduce interference. algorithms for assigning tones and for determining the orientation and broadcasting angles of the directional antennas are designed. design examples are given. Simulation result shows that the STS protocol gives better throughput-delay performance than the BTMA protocol, especially when the traffic is heavy. The VPTS protocol gives still better throughput-delay performance than the STS protocol.
The neutron supermirror is an important neutron optical device that can significantly improve the efficiency of neutron transport in neutron guides and has been widely used in research neutron *** types of algorithms,...
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The neutron supermirror is an important neutron optical device that can significantly improve the efficiency of neutron transport in neutron guides and has been widely used in research neutron *** types of algorithms,including approximately ten algorithms,have been developed for designing high-efficiency supermirror *** addition to its applications in neutron guides,in recent years,the use of neutron supermirrors in neutronfocusing mirrors has been proposed to advance the development of neutron scattering and neutron imaging instruments,especially those at compact neutron *** this new application scenario,the performance of supermirrors strongly affects the instrument performance;therefore,a careful evaluation of the design algorithms is *** this study,we examine two issues:the effect of nonuniform film thickness distribution on a curved substrate and the effect of the specific neutron intensity distribution on the performance of neutron supermirrors designed using existing *** effect of film thickness nonuniformity is found to be relatively insignificant,whereas the effect of the neutron intensity distribution over Q(where Q is the magnitude of the scattering vector of incident neutrons)is *** diagrams that show the best design algorithm under different conditions are obtained from these *** the intensity distribution is not considered,empirical algorithms can obtain the highest average reflectivity,whereas discrete algorithms perform best when the intensity distribution is taken into *** reasons for the differences in performance between algorithms are also *** findings provide a reference for selecting design algorithms for supermirrors for use in neutron optical devices with unique geometries and can be very helpful for improving the performance of focusing supermirror-based instruments.
The issue of introducing generic design constraints (practical or 'real-life' constraints) in robust control design procedures is discussed. A strategy, based on a hierarchy of optimisation methods, is propose...
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The issue of introducing generic design constraints (practical or 'real-life' constraints) in robust control design procedures is discussed. A strategy, based on a hierarchy of optimisation methods, is proposed here. An H-infinity design algorithm constitutes the bottom level of this hierarchy, and a general-purpose optimisation algorithm (a genetic algorithm) is employed for tuning the parameters of the H-infinity controller, searching for the solutions that satisfy the earlier mentioned 'practical constraints'. Practical results obtained in a pilot-scale plant with fluid-level and flow-rate control as controlled variables are included to show the applicability of the proposed method.
Although material and thermal coupling between the prefractionator and main distillation column renders the fully thermally coupled distillation column (FTCDC) a frequently favorable design option, it also complicates...
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Although material and thermal coupling between the prefractionator and main distillation column renders the fully thermally coupled distillation column (FTCDC) a frequently favorable design option, it also complicates considerably process synthesis and design. In this contribution, a simple algorithm for the synthesis and design of the FTCDC is derived with the optimization of an economical objective function. In terms of an initial process design chosen arbitrarily to meet the given product specification, the algorithm allows the treatment of the continuous operating variables (e.g., the vapor and liquid split ratios) and discontinuous structural variables (e.g., the number of stages in each column section) in a unified manner and permits searches of their optimum values sequentially in each iteration step. The proposed algorithm is characterized by great simplicity in principle and high robustness to the guess of initial process design and the thermodynamic properties of the mixtures separated. Five example problems dealing with the separation of various ternary mixtures with ideal and nonideal thermodynamic properties are employed to evaluate the proposed procedure, and the obtained results demonstrate its applicability and robustness to the synthesis and design of the FTCDC.
The paper by Han et al. presents an algorithm for strictly-proper fixed-ordercontroller design under an LMI formulation with an H_∞ performance condition. The proposedalgorithm is applied to the active suspension ben...
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The paper by Han et al. presents an algorithm for strictly-proper fixed-ordercontroller design under an LMI formulation with an H_∞ performance condition. The proposedalgorithm is applied to the active suspension benchmark system in the Laboratoire d'Automatique deGrenoble (LAG). The contribution of this paper can be devised in two perspectives: (1) A designalgorithm for optimal H_∞ fixed-order controllers using LMIs. (2) New methodology applied to theactive suspension system.
We show that points can be removed from the design space during the search for a D-optimum design, using a simple inequality satisfied by support points of a D-optimum design measure. This inequality does not seem to ...
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We show that points can be removed from the design space during the search for a D-optimum design, using a simple inequality satisfied by support points of a D-optimum design measure. This inequality does not seem to have been noticed before but may be used for accelerating algorithms for D-optimum design, or for the determination of minimum covering ellipsoids, as used, e.g., in ellipsoidal trimming. (C) 2003 Elsevier Science B.V. All rights reserved.
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