494 research outputs found

    Pulp and Paper Wastewater Color Removal

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    Pulp and paper industries generate highly-colored wastewaters, the color of which is not removed by conventional biological treatment. As a result, the persistent color of the wastewater can potentially disrupt the aesthetic appearance of the recieving stream as well as releasing potentially toxic compounds to the environment. Coagulation and flocculation is a chemical treatment practiced to remove color from pulp and paper mill wastewaters. The main focus of this work was to study the color removal efficiency of coagulation/flocculation treatment on a specialty pulp and paper mill wastewater located in the State of Tennessee. In this regard, the effect of coagulant, coagulant aid, and flocculent dosages as well as the wastewater pH and temperature on color removal process were examined. Furtheremore, bentonite clay and powdered activated carbon (PAC) effectiveness for color removal were tested

    Design and implementation of a 3D computer game controller using inertial MEMS sensors

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    Though 3D computer graphics has seen tremendous advancement in the past two decades, most available mechanisms for computer interaction in 3D are high cost and targeted for industry and virtual reality applications. Recent advances in Micro-Electro-Mechanical-System (MEMS) devices have brought forth a variety of new low-cost, low-power, miniature sensors with high accuracy, which are well suited for hand-held devices. In this work a novel design for a 3D computer game controller using inertial sensors is proposed, and a prototype device based on this design is implemented. The design incorporates MEMS accelerometers and gyroscopes from Analog Devices to measure the three components of the acceleration and angular velocity. From these sensor readings, the position and orientation of the hand-held compartment can be calculated using numerical methods. The implemented prototype is utilizes a USB 2.0 compliant interface for power and communication with the host system. A Microchip dsPIC microcontroller is used in the design. This microcontroller integrates the analog to digital converters, the program memory flash, as well as the core processor, on a single integrated circuit. A PC running Microsoft Windows operating system is used as the host machine. Prototype firmware for the microcontroller is developed and tested to establish the communication between the design and the host, and perform the data acquisition and initial filtering of the sensor data. A PC front-end application with a graphical interface is developed to communicate with the device, and allow real-time visualization of the acquired data

    Monotonic Testing of Fully and Partially Anchored Wood-Shear Walls

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    Currently in the United States of America (USA), there are around 125 million single-family dwellings (SFDs), most of which consist of wood-frame construc-tion (SSA 2015). Traditionally wood frame construction SFDs have performed well in seismic events but more efficient designs against earthquake loads is de-sired. More than 143 million Americans are living in seismic regions and nearly 28 million live in high seismic regions (SSA 2015). During an earthquake event, the lateral forces created are characterized as cyclic and random. The main lateral force resisting system for these wood-frame SFDs is the shear wall, there-fore it is critical that the shear wall has the ability to resist cyclic and random lateral forces. This study focuses on the effects of earthquake loads on residen-tial wood shear walls

    Modeling and optimization of production and distribution of drinking water at VMW

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    We develop and discuss an operational planning model aiming at minimizing production and distribution costs in large drinking water networks containing buffers with free inflow. Modeling drinking water networks is very challenging due of the presence of complex hydraulic constraints, such as friction losses and pump curves. Non-linear, non-convex constraints result from the relationships between pressure and flow in power terms. Also, binary variables are needed to model the possibility of free inflow or re-injection of water at reservoirs. The resulting model is thus a non-convex Mixed-Integer Non-Linear Program (MINLP). A discrete-time setting is proposed to solve the problem over a finite horizon made of several intervals. A commercial solver, BONMIN, suited for convex MINLP models is used to heuristically solve the problem. We are able to find a good solution for a small part of an existing network operated by the Vlaamse Maatschappij voor Watervoorziening (VMW), a major drinking water company in Flanders

    A Comparative Study of Several Array Geometries for 2D DOA Estimation

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    AbstractIn this paper, a comparison between several array geometries, including planar arrays and volume arrays, for two-dimensional Direction of Arrival (DOA) estimation using Multiple Signal Classification (MUSIC) is presented. For each geometry, various criteria is taken into consideration and a comparative study of the performance of geometries is carried out. The geometries together with their ultimate direction finding performance are compared based on Root Mean Square Error (RMSE), the ambiguity functions, and Cramer-Rao Bounds (CRB). Furthermore, the effects of phase and amplitude variations of the array element radiation pattern, namely Vivaldi and Monopole antenna, on DOA estimation performance are studied. The advantages and drawbacks of each geometry vis-Ă -vis the employed DOA estimation technique are shown through a numerical comparison

    Impact of ultrasound on extractability of native collagen from tuna by-product and its ultrastructure and physicochemical attributes

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    The effect of ultrasound treatment (300 W; 0, 5, 10, 15, 20 and 25 min) on the extractability of acid soluble collagen from yellowfin tuna skin and its structural, physicochemical and functional properties were investigated. Ultrasound treatments significantly increased collagen extraction yield from the tuna skin up to 2.7 times, compared to the conventional extraction with acetic acid. The level of proline, hydroxyproline and thermal stability of collagens increased by applying ultrasound while their native triple-stranded helical structure was well-preserved, as revealed by X-ray diffraction and FTIR spectroscopy. However, ultrasound treatment reduced the particle size of the collagens which increased their pH and salt induced solubility. The water holding capacity and the emulsifying properties of ultrasound treated collagens were also higher than those produced with the conventional method. Altogether, the results suggested that ultrasonication can be a promising assistant technology for improving native collagen extraction efficiency from tuna skin and its functionality but its duration should be carefully optimized

    Ground Improvement to Reduce Liquefaction Potential Using Vibrocompaction and Stone Columns

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    With the rapid pace of industrialization, structures are being designed and constructed in the flood plains of major rivers. In earthquake prone areas, a fundamental issue in the design and construction of structures on saturated sandy soils is weather or not the design earthquake could initiate liquefaction in the form of lateral spreading, sand boils, settlement, or cracking. Many different methods, including vibrocompaction, deep dynamic compaction, compaction piles, geopiers, deep mixing, vibratory probes, displacement/compaction grout, etc., have been used to reduce the liquefaction potential at various sites. Use of vibrocompaction to densify cohesionless soil is becoming more common and cost effective. For projects in the New Madrid seismic zone (NMSZ) another challenge to perform site specific analysis is the lack of recorded ground motions. Therefore, synthetic time histories need to be generated using the attenuation models applicable to the region. This paper provides details about a site specific study performed for a site in the bootheel area of Missouri, and results of liquefactions analysis and ground modification achieved using vibrocompaction

    Irregular shaped building design optimization with building information modelling

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    This research is to recognise the function of Building Information Modelling (BIM) in design optimization for irregular shaped buildings. The study focuses on a conceptual irregular shaped “twisted” building design similar to some existing sculpture-like architectures. Form and function are the two most important aspects of new buildings, which are becoming more sophisticated as parts of equally sophisticated “systems” that we are living in. Nowadays, it is common to have irregular shaped or sculpture-like buildings which are very different when compared to regular buildings. Construction industry stakeholders are facing stiff challenges in many aspects such as buildability, cost effectiveness, delivery time and facility management when dealing with irregular shaped building projects. Building Information Modelling (BIM) is being utilized to enable architects, engineers and constructors to gain improved visualization for irregular shaped buildings; this has a purpose of identifying critical issues before initiating physical construction work. In this study, three variations of design options differing in rotating angle: 30 degrees, 60 degrees and 90 degrees are created to conduct quantifiable comparisons. Discussions are focused on three major aspects including structural planning, usable building space, and structural constructability. This research concludes that Building Information Modelling is instrumental in facilitating design optimization for irregular shaped building. In the process of comparing different design variations, instead of just giving “yes or no” type of response, stakeholders can now easily visualize, evaluate and decide to achieve the right balance based on their own criteria. Therefore, construction project stakeholders are empowered with superior evaluation and decision making capability

    SSP: An interval integer linear programming for de novo transcriptome assembly and isoform discovery of RNA-seq reads

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    AbstractRecent advances in the sequencing technologies have provided a handful of RNA-seq datasets for transcriptome analysis. However, reconstruction of full-length isoforms and estimation of the expression level of transcripts with a low cost are challenging tasks. We propose a novel de novo method named SSP that incorporates interval integer linear programming to resolve alternatively spliced isoforms and reconstruct the whole transcriptome from short reads. Experimental results show that SSP is fast and precise in determining different alternatively spliced isoforms along with the estimation of reconstructed transcript abundances. The SSP software package is available at http://www.bioinf.cs.ipm.ir/software/ssp
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