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A hybrid plant and aquarium system can save water via water circulation and filtering. In order to conveniently seed and harvest and breed in the aquarium, the system is a module. The seeding/harve...

Based on the phase-cancellation technique, multi-connected-tube mufflers have been applied in the noise elimination for industrial venting noise. On the basis of the transfer matrix method, most re...

There has been wide-spread use of plane wave theory in muffler design in industry. However, This has led to an underestimation of acoustical performances at higher frequencies. To overcome the above drawback, the finite element and boundary element methods have been developed. Nevertheless, the time consumed in calculating the noise level is unacceptable. Moreover, considering the acoustical effect and necessity of space-constrained situation in industry, a compact design of reverse mufflers which may improve the acoustical efficiency is then proposed.In this paper, a numerical assessment of rectangular mufflers hybridized with straight/reverse chambers using eigen function, four-pole matrix, and genetic algorithm under limited space is developed. Before the optimization is performed, an accuracy check of the mathematical models for the muffler will be carried out. Results reveal that the noise reduction will increase when the number of chambers increases. In addition, the acoustical performance of the mufflers is reversely proportional to the diameter of the inlet/outlet tubes. Also, the TL of the mufflers will be improved when using more number of target tones in the objective function. Consequently, a successful approach in searching optimal shaped rectangular straight/reverse mufflers using an eigen function and a genetic algorithm method within a constrained space has been demonstrated.

In order to overcome the drawback of the accuracy for the Plane wave theory in the muffler’s acoustical calculation in the region of higher frequencies, we use a theoretical analysis of eigen function in conjunction with a four-pole system matrix to evaluate the TL of a circular straight muffler with bias inlet/outlet duct. With this method, the acoustical calculation can be speeded up comparing to traditional simulation of FEM and BEM method. Consequently, results reveal that the bias effect will tremendously influence the acoustical performance of the muffler.

Research on plenums partitioned with multiple baffles in the industrial field has been exhaustive. Most researchers have explored noise reduction effects based on the transfer matrix method and the boundary element method. However, maximum noise reduction of a plenum within a constrained space, which frequently occurs in engineering problems, has been neglected. Therefore, the optimum design of multi-chamber plenums becomes essential. In this paper, two kinds of multi-chamber plenums (Case I: a two-chamber plenum that is partitioned with a centre-opening baffle; Case II: a three-chamber plenum that is partitioned with two centre-opening baffles) within a fixed space are assessed. In order to speed up the assessment of optimal plenums hybridized with multiple partitioned baffles, a simplified objective function (OBJ) is established by linking the boundary element model (BEM, developed using SYSNOISE) with a polynomial neural network fit with a series of real data – input design data (baffle dimensions) and output data approximated by BEM data in advance. To assess optimal plenums, a genetic algorithm (GA) is applied. The results reveal that the maximum value of the transmission loss (TL) can be improved at the desired frequencies. Consequently, the algorithm proposed in this study can provide an efficient way to develop optimal multi-chamber plenums for industry.

Ventilation equipment will inevitably deteriorate causing overheating problems that result in a machine breaking down. Therefore, to insure the safety of the machine, an auto- matic thermal control and online monitoring system is compulsory. In addition, to reduce manpower, a remote temperature monitoring/control system is proposed. Moreover, in order to recheck site status, an IP CAM used to audit current conditions will also be installed. The machine room will be equipped with a thermal detector, an auxiliary fan, and an alarm. The control system will also automatically detect current temperature in the machine room. Aux- iliary ventilation will be engaged when the temperature rises. An alarm unit will also be actu- ated when the temperature exceeds a preset limit. An image of the machine room captured by the IP CAM will be forwarded to both the server and the client via a TCP/IP protocol.Results reveal that the temperature for a machine room can be controlled online at a specified range. Additi...

There has been considerable research done on multi-chamber mufflers used in the elimination of industrial venting noise. However, most research has been restricted to lower frequencies using the plane wave theory. This has led to underestimating acoustical performances at higher frequencies. Additionally, because of the space-constrained problem in most plants, the need for optimization of a compact muffler seems obvious. Therefore, a muffler composed of multiple rectangular fin-shaped chambers is proposed. Based on the eigenfunction theory, a four-pole matrix used to evaluate the acoustic performance of mufflers will be deduced. A numerical case for eliminating pure tones using a three-fin-chamber muffler will also be examined. To delineate the best acoustical performance of a space-constrained muffler, a numerical assessment using the Differential Evolution (DE) method is adopted. Before the DE operation for pure tone elimination can be carried out, the accuracy of the mathematical model must be checked using experimental data. The results reveal that the broadband noise has been efficiently reduced using the three-fin-chamber muffler. Consequently, a successful approach in eliminating a pure tone using optimally shaped three-fin-chamber mufflers and a differential evolution method within a constrained space has been demonstrated.

At present, there is a trend to design a hard disk with a larger capacity, a faster revolution speed, and a precise mechanism. Therefore, the influence of data transmission with respect to vibration is obvious. To reduce interference of the vibrational impact on the data transmission efficiency, vibrational abatement on the hard disk using the damping material becomes crucial. Because of the complicated relationship for the damping coefficient and spring constant to the hardness (D1, D2, and D3) of the damping material installed under the hard disk, it is difficult to theoretically assess an optimal hardness combination of the damping material. Therefore, an alternative way by using an experimental study in conjunction with Taguchi method, an Artificial Neural Network (ANN), and a GA Method is proposed. In this paper, a hard disk is placed on a vibration tester that is an analogue to a dynamic vibrational circumstance induced by a vibrational base. The data transfer rate of the hard disk will be detected by using IOmeter software under various base-excitation accelerations, tilted angles of the hard disk, and targeted frequencies. To reduce the vibrational impact on the data transmission efficiency, an assessment of an optimal three-layer damping material installed under the hard disk using the Taguchi method, the Artificial Neural Network (ANN), and the GA Method is proposed. Before the optimization of the damping material is performed, the required experimental sets (the hardness for three layers of damping material) of the data transmission testing with respect to various design parameters will be determined by using the Taguchi method. The ANN, a simplified objective function (OBJ), will be established by inputting the hardness of three layers of damping material and their related data transmission efficiency at three targeted frequencies. Thereafter, the optimal hardness for three layers of the damping material will be obtained using a genetic algorithm (GA). Consequently, the optimal hardness of the three-layer damping material with respect to various tilted angles and target frequencies will be assessed.

To increase manufacturing productivity, industrial automation is required. Additionally, in order to monitor the manufacturing process, a remote online monitoring and control system becomes compulsory. A conventional remote monitoring system often uses a wire connection for communication within a control center; however, it is time-consuming and inconvenient. To overcome this drawback, a wireless design is proposed for the manufacturing process. In this paper, a case study of a remote wireless monitoring network used in a shape judgment system is introduced. In order to connect the server pc and the PLC (a controller of a shape judgment system), a ZigBee wireless module in conjunction with a transparent mode is used. Additionally, the interface of the above system is established with a Visual Basic 6.0. One of the advantages in using a wireless network to connect with a server pc and a shape judgment system is that the server pc is movable. Moreover, the remote monitoring function at the client pc can also be utilized using a TCP/IP protocol. Consequently, a prototype of a wireless network and a remote control for a shape judgment system using a ZigBee module that reduces the cost in electrical power and saves time in the system’s installation is exemplified.

Rectangular mufflers internally hybridized with splitters have been extensively applied in industrial noise abatement. However, there has been a palpable lack of academic work directed toward space-constrained mufflers conjugated with multi-channel splitters that disperse venting fluid and reduce secondary noise. That being so, an analysis of the Sound Transmission Loss (STL) of rectangular mufflers internally hybridized with multiple parallel splitters that are optimally designed to perform within a limited space will be considered, here. By using an acoustical lumped method, a four-pole system matrix for evaluating the acoustic performance (STL) emerges. During the optimization process, the simulated annealing (SA) method, which is a robust scheme utilized to search for the global optimum by imitating a physical annealing process, is used. Before dealing with a broadband noise, the STL’s maximization relative to a one-tone noise (250Hz) is offered to confirm the SA method’s reliability. Moreover, the mathematical model is also checked for accuracy. To appreciate the influence of acoustical efficiency with respect to the design parameters, the sensitivity analysis of six design parameters (dh: the diameter of a perforated hole; W: the width of air channel; R: acoustic flow resistivity of the acoustic fiber; σ : the porosity of the perforated plate; Df: the thickness of the acoustic fiber; L1: the horizontal length of the splitter) is performed. Subsequently, to bring into focus the acoustical interaction with respect to the number of air-channels (between the splitters), three types of mufflers (mufflers A∼C) hybridized with one, two, and four air-channels (with parallel splitters) have been surveyed. Results divulge that for a rectangular muffler internally conjugated with a one-channel splitter, the maximal STL is located at the desired tone. The acoustical performance of a rectangular muffler will increase and the induced back pressure will decrease simultaneously if the number of the splitters internally conjugated within the rectangular muffler increases. Consequently, optimally designed rectangular mufflers with multiple parallel splitters that avoid secondary noise induced by high speed flow while simultaneously maximizing acoustical performance within a constrained space are preferable.

A traditional scarecrow does not scare birds; subsequently, crops will be demolished by birds during the growing season. Moreover, because farms are often invaded and crops stolen during harvest, the farmer and his dogs are forced to stay and protect the crops. However, this is not efficient for a large farm. Therefore, a remote crop monitoring security system is necessary. In order to maintain sufficient electrical power used by the system, green electrical energy generated by both a solar board and a wind generator are adopted. This system placed in each section of the farm includes five ultrasonic sensors, a microcontroller, a twinkling lighting, and a speaker unit. To ensure efficiency when using the crop security system, crops in huge areas will be divided into several small zones for monitoring. Each zone will have an individual crop security system. When a sensor detects an intrusion of birds, the alarm and light will be initiated. With this, any birds or other intruders will be scared and leave the field.

There has been, of recently, much research on mufflers lined with sound absorbing material. In dealing with high frequency noise emitted from venting systems, a sound absorbing material inside a tube covered with a perforated plate has been used. However, the acoustical performance of mufflers equipped with one-layer of sound absorbing material has still proved to be insufficient. In order to promote acoustic performance, a design and theoretical assessment on pod mufflers hybridized with multi-layer concentric sound- absorbing rings is proposed. By using the acoustical-lumped-method, a four-pole system matrix for evaluating the acoustic performance (STL) will emerge. During the optimization process, the simulated annealing (SA) method, which is a robust scheme utilized to search for the global optimum by imitating a physical annealing process, is used. Before dealing with a broadband noise, the STL’s maximization relative to a one-tone noise (1000Hz) is offered to confirm the SA method’s reliability. To appreciate the influence of acoustical efficiency with respect to the design parameters, an analysis of design parameters (dh: the diameter of a perforated hole; W: the width of an air channel; R: acoustic flow resistivity of the acoustic fiber; σ : the porosity of the perforated plate; Df: the thickness of the acoustic fiber; L1: the horizontal length of the sound absorbing ring) is completed. Subsequently, to bring into focus the acoustical interaction with respect to the number of air-channels (between the sound absorbing rings), three types of mufflers (mufflers A∼C) hybridized with one, two, and three air-channels have been surveyed. Results reveal that for a rectangular muffler internally conjugated with one air-channel, the maximal STL is located at the desired tone, and the acoustical performance of a cone muffler will increase if the number of air-channels internally conjugated within the cone muffler increases. Consequently, the approach used for the optimal design of the STL on pod mufflers internally equipped with multiple air-channels within a space-constrained situation can be easily assessed.

Because of the inevitable depletion of oil and pollution caused by the use of fossil fuels, an alternate energy source that is clean and sustainable is necessary. Wind energy is that source. It is clean, safe, and environmentally friendly.In this paper, an axial-fan-type wind generator system used to generate electricity to recharge a battery (DC 12V) is proposed. The recharged battery, which is portable, can serve as an energy resource for electric vehicles. Moreover, in order to limit manpower, a PC-base remote electrical monitoring technique used in the battery recharging system via the TCP/ IP network is used.Consequently, a prototype of a PC-base monitoring system in conjunction with a wind generator with a 30 Watts capacity is established.

A three-dimensional numerical model using the finite element method is proposed in the present study to accurately simulate the influences of the thermal resistance on the submount of an LED. In a system with adiabatic lateral boundaries, the internal thermal resistance of the submount is principally analyzed from the series connection effect of the spreading thermal resistance and one-dimensional material resistance. However, the total thermal resistance is used for analysis under various heat dissipating conditions due to the complex coupling relations among the material resistance, the spreading thermal resistance, and the external thermal resistance. A higher contact ratio between heat source and submount, a larger external convective effect, and dissipation of heat from the symmetrical axis of the submount will decrease the spreading thermal resistance.

To assure product quality, an early warning and inspection system to predict the variation (trend) of a products quality (i.e. the product thickness) in the manufacturing process is necessary. Here, a manual online measurement of a production line installed with an online automatic warning system that will prevent manually accumulated errors from occurring is presented. Using this system, a quality trend profile will be made. The abnormal trend distribution will be obtained by randomly selecting the period of the quality trend profile and translating it into a time distribution bar chart. The monitoring online system will be pre-warned via the abnormal trend distribution. A products thickness can be obtained using a linear variable differential transformer (LVDT). The analogue signal will be transmitted to the AD converter of the PLCs analogue input channel. The digital signal will be transmitted from the series port to the remote PC via the web control unit. A profile of the products thickness measured by the LVDT will be monitored online and dynamically exhibited in the web-based remote system by using an embedded Javascript, an HTML, and a web control unit. The upper/lower thresholds will be preset in the product thickness profile. In addition, the quality monitoring system will be pre-warned via the time distribution bar chart when the abnormal trend distribution occurs. Consequently, the web-base monitoring system can be extended to remotely connect to all the LVDT devices.

Pollution and climate change due to the use of fossil fuel can no longer be denied, and this coupled with a waning supply of oil leads one to inevitably conclude that a clean, sustainable energy source is needed. That source is solar energy, the cleanest, safest, and most environmentally friendly energy source we have. In this paper, a photovoltaic (PV) solar energy system is used to generate electricity that will recharge a battery (DC 12V). The portable recharged battery will serve as the energy source for an electric vehicle. Moreover, in order to reduce manpower, a PC-based remote electrical monitoring technique used in the battery’s recharged system will be established via a TCP/IP network. Consequently, a PV solar panel with a 30 Watt capacity used to generate electricity using a PC-based monitoring system is exemplified.

Excessive raw materials and products in stock unduly increase an enterprise's overhead. However, insufficient raw materials and products will also influence the efficiency and output of the manufacturing process. Therefore, to largely reduce stock cost and facilitate adequate production for plants with multiple manufacturing processes and warehouses, the adjustment of raw material and products between warehouses is necessary. In addition, in order to keep track of current raw materials and products, remote online monitoring and control of the storage/retrieval system is compulsory. To simplify the search in an AS/BS process, a graph-aided strategy that manually selects the location within the stock map is presented. Moreover, to avoid interference from internet wiring allocation with existing equipment, a wireless storage/retrieval system using the ZigBee module is adopted. Consequently, a prototype of the remote wireless monitoring and control storage/retrieval system for sixteen storage spaces is exemplified.

A numerical simulation model to obtain the extra-low internal thermal resistance for submount of LED is presented. The 3-D numerical model for calculating thermal resistance is demonstrated on examining the aspect ratio of submount, the contact ratio between chip and submount, and the surrounding condition. According to the analysis by accurate numerical simulations of heat transfer; the appropriate dimensions for different conditions of ambient are determined. The thickness of submount should be over a specially designated value. Besides, a higher contact ratio between heat source and submount, a larger external convective effect, and the heat dissipated from symmetry axis of submount will decrease the spreading thermal resistance.

For the petroleum industry, to reduce the risk of a gas explosion in dangerous working areas, the use of explosion-proof equipment such as air-driven devices which are free from explosions becomes essential. Moreover, for the purpose of saving manpower, a remote operation using a robot via a visual monitoring system and a network is used. However, to overcome the drawback of costly manpower and to improve safety in explosion-prone zones, a three-axis robot using a remote network control system is proposed. In this paper, the three-axis robot can be monitored online via the USB protocol. Furthermore, it also can be remotely manipulated via the TCP/IP protocol by clicking the command of the VB interface on the client pc. Consequently, the remote-control three-axis robot can not only work for people in severe and dangerous circumstances but also can reduce the cost of manpower.

The fatigue reliability of Gr/PEEK composites has been investigated in the present study. In the experimental investigation, constant amplitude loading, multiple-level loading and random loading have been considered step by step during the fatigue tests. In particular, a residual strength degradation model was presented for predicting the fatigue life of composites subjected to constant amplitude fatigue loading. The accumulation of fatigue damage was determined, using the residual strength degradation model. The residual strength distribution after an arbitrary fatigue cycle can be represented by a two-parameter Weibull distribution function. A fatigue reliability analysis method for arbitrary load history was thus developed through the Weibull distribution function. Good correlation between theory and experiment was obtained for constant amplitude loading, two-level loading, three-level loading and random loading. The result of the present study can be used as a basis for the reliability design of mecha...

Because a toxic gas detecting/monitoring system in a chemical plant is not movable, a gas detecting/monitoring system will be passive and the detecting range will also be constrained. This invention is an active multi-functional wireless patrol car that can substitute for humans that inspect a plant's security. In addition, to widen the monitoring vision within the environment, two motors used to rotate a wireless IPCAM with two axes are presented. Also, to control the robot car's movement, two axis motors used to drive the wheel of the robot car are also installed. Additionally, a toxic gas detector is linked to the microcontroller of the patrol car. The detected concentration of the gas will be fed back to the server pc. To enhance the robot car's patrolling duration, a movable electrical power unit in conjunction with a wireless module is also used. Consequently, this paper introduces a wireless path-patrol and toxic gas detecting security robot car that can assure a plant's security and protect workers when toxic gases are emitted.

Performing electrical test is the most challenge process in the 3D-IC device fabrication and manufacturing. There have been many papers published and presented for 3D-IC device testing technology such as 3D-IC design for test, test for less in the 3D-IC manufacturing etc… Most of them are circuit design related techniques. In this paper we will discuss a different point of view in the device packaging technologies that may affect the cost of testing. The main technologies for integrating and fabricating the 3D-IC device and system are (1) Through Silicon Via (TSV) technology for vertical communication; (2) interconnecting technology to accomplish the up and down signal flow between wafer layers and (3) stacking technology to complete the final assembly of the 3D-IC device and system. One very important step in the integration and manufacturing process is the testing and evaluating of the 3D-IC stacked system. This paper will dedicate to the issue of choosing the right interconnecting technology for cost effective consideration by introducing the Micro Bridge Technology. With the right choice of interconnecting technology, we will be benefited from the reduction of the 3D-IC system integration and testing through both cost and complexity.