Taiwan Association of Engineering and Technology Innovation: E-Journals
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The Study of Tibicos Fermentation Product as Pilot Model of Healthy Drinks
Get PDFSugar kefir grains (Tibicos) are a symbiotic culture of bacteria and yeasts which were assembled by various strains of microbes attached polysaccharide bracket composed of white transparent particles. Initially, we used chemical colorimetric method to measure that of carbohydrate concentrations, and Brad ford method for that of protein concentrations. We utilized black sugar as carbohydrate source and medium to cultivate Tibicos, and collected media after 0 hr., 24 hr., and 48 hr. different time points. These collected Tibicos grains and fermentation broth were measured with the above methods.In addition, we used Gram stain to observe the inside microbial populations of Tibicos. The results showed that the weight of cultured grains with brown sugar solution at 25 ℃ and sealed for 48 hr increased to 45% as that of original grains. The components of Tibicos fermentation broth were analyzed by HPLC for ions as following: Lactic acid, Chloride ion, Malate, Sulfate, Oxalic acid, Phosphate, Citrate, and other minor ingredients.Furthermore, we used the Gram stain to observe the microbial composition within Tibicos grains. The more detail identification of microbial population in Tibicos was done with bacteria and yeasts. The bacteria parts used PCR amplification with the 16S rDNA primer sets (533R and 341Fgc), gel purification, fragments sequencing, and alignment with 16S ribosomal RNA sequences in NCBI database (16S rDNA of Bacteria and Archaea). The result sequences were assigned as Bacillus strain as following: (a) Bacillus circulans, (b) Bacillus eiseniae, (c) Bacillus oceanisediminis, (d) Bacillus atrophaeus, (e) Bacillus siralis, (f) Bacillus massiliosenegalensis. The Yeast parts were first isolated as single colony, purified the chromosomal DNA, and amplified by PCR method with 18 S rDNA primer set (FR1 and NS1), then gel purified, DNA sequenced, and aligned in NCBI database (Nucleotide collection). The identified yeast strains as following: (a) Sporobolomyces koalae, (b) Meyerozyma guilliermondii, (c) Aureobasidium pullulans
Reliability Study of GaN-on-SiC HEMT RF Power Amplifiers
Get PDFThe RF power amplifier demonstrators containing each one GaN-on-SiC, HEMT, CHZ015A-QEG, from UMS in SMD quad-flat no-leads package (QFN) were subjected to thermal cycles (TC) and power cycles (PC) and evaluated electrically, thermally and structurally. Two types of solders, Sn63Pb36Ag2 and lead-free SnAgCu (SAC305), and two types of TIM materials, NanoTIM and TgonTM 805, for PCB attachment to the liquid cold plate were tested for thermo-mechanical reliability. Changes in the electrical performance of the devices, namely the reduction of the current saturation value, threshold voltage shift, increase of the leakage current and degradation of the HF performance were observed as a result of an accumulated current stress during PC. No significant changes in the investigated solder or TIM materials were observed
MF Integrator: A Module for Converting METAFONT into Outline Font
Get PDFMETAFONT is a description language that generates TeX-oriented bitmap fonts which are not popular outside the TeX world. The number of fonts prepared with METAFONT are very small compared with outline fonts. Font libraries like FreeType, which are used to render fonts in outline and some bitmap formats doesn’t provide any support for METAFONT. A research, MFCONFIG module added an indirect support of METAFONT inside FreeType rasterizer but it has problems of performance and dependency. In this paper, we have proposed a module named MF Integrator for FreeType rasterizer. The proposed module overcome the problems of performance and dependency of MFCONFIG module. Authors tested proposed module with a client application which is used to display styled text on screen. Users can now take the benefits of METAFONT by using our proposed MF Integrator module
Axial and Flexural Strength of Square RC Columns with No-rounded Corners Wrapped with CFRP under Eccentric Loading
Get PDFThis paper presents the results of a study on the axial and flexural strength of reinforced concrete (RC) columns with no-rounded corners wrapped with Carbon Fiber Reinforced Polymer (CFRP) under eccentric loading based on an experimental program. The main parameters under investigation are the number of layers of CFRP wrap. Thirty-six concrete cylinders with a standard size of (150×300) mm were cast and tested in this study to get the modulus of elasticity and compressive strength of concrete. Of these 36 concrete cylinders were divided into four groups, unwrapped, wrapped with one layer of CFRP, wrapped with two layers of CFRP, and wrapped with three layers of CFRP. Twelve rectangular reinforced concrete columns were also cast and tested in this study. The column specimens had dimensions (75×75×750) mm with no-rounded corners of the column section. The column specimens were also divided into four groups, unwrapped, wrapped with one layer of CFRP, wrapped with two layers of CFRP, and wrapped with three layers of CFRP. The experiment results show that the load-carrying capacity of the wrapped column increased by the increasing number of CFRP layers. Comparing the experimental results with the compressive strength concrete and the maximum load-carrying capacity of wrapped RC Column predicted by the theories proposed by several researchers with the concern of no-rounded corners were also presented
Optimized Feature Extraction for Precise Sign Gesture Recognition Using Self-improved Genetic Algorithm
Get PDFOver the past two years, gesture recognition has become the powerful communication source to the hearing-impaired society. Furthermore, it is supportive in creating interaction between the human and the computer. However, the intricacy against the gesture recognition arises when the environment is relatively complex. In this paper, recognition algorithm with feature selection based on Self-Improved Genetic Algorithm (SIGA) is proposed to promote proficient gesture recognition. Furthermore, the recognition process of this paper includes segmentation, feature extraction and feed- forward neural network classification. Subsequent to the gesture recognition experiment, the performance analysis of the proposed SIGA is compared with the conventional methods as reported in the literature along with standard Genetic Algorithm (GA). In addition, the effect of optimization and the feature sensitivity is also demonstrated. Thus, this method makes aggregate performance against the conventional algorithms
Dual Polling Protocol for Improving Performance in Wireless Ad Hoc Networks
Get PDFAn ad hoc network is based on a distributed coordination function (DCF) to transmit data packets through channel contentions. In DCF, when the number of stations increases, performance degrades considerably because of extremely high collision probability. To improve performance, a distributed point coordination function (DPCF) protocol was proposed. In this protocol, stations operate as in DCF to obtain channel access rights. When a station obtains access rights, it polls all neighboring stations by using point coordination function (PCF). The polled stations then transmit their data packets without channel contentions. However, this protocol aggravates the issue of hidden terminals and causes channel wastage. To solve these problems, we propose a protocol in which a station polls stations in limited areas as opposed to every station in its transmission range. In addition, it polls only stations with data packets. The proposed protocol lowers the probability of collision and improves network performanc
Advanced Waste Heat Recovery Systems within Hybrid Powertrains
Get PDFA waste heat recovery system (WHRS) is very well known to provide no advantage during the cold start driving cycles, such as the New European Driving Cycle (NEDC), which are used for certification of emissions and assessment of fuel economy. Here, we propose a novel integrated WHRS using the internal combustion engine (ICE) coolant passages and an exchanger on the exhaust working as pre-heater / boiler / super-heater of a Rankine cycle. The expander is connected to an electric generator unit (GU), and the pump is connected to an electric motor unit (MU). The vehicle is also fitted with an electric, kinetic energy recovery system (KERS). The expander and condenser are bypassed during the first part of the NEDC when the vehicle covers the four ECE-15 (Economic Commission for Europe - 15) - UDC (Urban Drive Cycle) segments where the engine warms-up. Only after the engine is fully warmed up, during the last part of the NEDC, the extra urban driving cycle (EUDC) segment, the expander and condenser are activated to recover part of the coolant and exhaust energy
Sensor Data Abstraction for Failure Prediction of Polymerase Chain Reaction Thermal Cyclers
Get PDFIn this paper, the heating and cooling rates of polymerase chain reaction thermal cyclers was analysed over time, to predict their aging. Two kinds of methods were applied to calculate the rise times of the heating and cooling protocol sections, which were inversely related to the heating or cooling rates. The temporal changes of the rise times were investigated over several months. For three thermal cyclers with different structures, the increases of the rise times were fairly linear; therefore, the aging prediction is feasible
A Context Retrieval Method for Context-awareness Using Ontology-Based Approach in Internet of Things Environments
Get PDFA context-aware system is required for providing context-aware services to users in the Internet of things (IoT) environment. It consists of three primary tasks: gathering context data, abstracting the collected data, and providing services to users. In IoT environments, context data are generated by a large number of sensors, and this context data are part of the context-awareness services provided to the users. When the context-aware system provides context-aware services with their service descriptions, it is necessary to process the data gathered by abstracting and contextualizing them. Generally, the context-aware system encounters a problem in that the context representations between contextualized sensor data and their related service descriptions do not match well. We herein propose a context retrieval method that facilitates in obtaining context information for the context-aware system in IoT environments. The context-aware system communicates with an ontology module that handles input data described in a set of universal resource identifiers, as a triplet. The ontology module resolves each representation request from the context-aware system. The proposed method provides an ontology-based mapping procedure for the context representation problem described above
Development of an Automated Measurement System for Checking Irradiation Non-uniformity of Solar Simulators
Get PDFGenerally, for some solar simulator manufactures, the measurement of irradiation non-uniformity is made by placing a PV cell artificially and point by point on each measuring point on the solar module. It records each corresponding output voltage of PV cell. It is time-consuming and easy to produce measurement error. If either an XY table or a multi-axis robot is applied in this case, it is ot only expensive but also difficult to carry and setup. Hence, an innovative and automated measurement system, which consists of both a self-developed smart robot and a monitoring and control system, is proposed in this paper to solve aforementioned problems. The monitoring and control system, i.e., constructed by a PC and a self-developed LabVIEW-based application program, plays the role of remotely commanding the operation mode of a robot, receiving the irradiance data being transmitted from the robot and calculating the irradiation non-uniformity. Once the irradiation non-uniformity is calculated, some operations are made to adjust the irradiation parameters of the solar simulator such that the irradiation non-uniformity can meet the specification, i.e., 2%, 5%, 10% for class A, B or C of solar module, respectively