1,720,961 research outputs found

    Car exhaust waste heat recovery using hexagon shaped thermoelectric generator / Muhammad Fairuz Remeli, Baljit Singh and Aiman Ismail

    Full text link
    Heat recovery technology using thermoelectric has attracted many research intentions mainly for its ability to generate power passively. The automotive engine usually produces waste heat ranging from 30-40% due to the thermodynamic limit. The use of thermoelectric generator (TEG) for waste heat recovery and power generation could increase the efficiency of the internal combustion engine system. This research developed and investigated a heat recovery system using a thermoelectric generator (TEG) for power generation. A thermoelectric generator (TEG) consisted of thermoelectric modules, hexagonal pipe connector and heat sinks was built and connected to an exhaust pipeline. A theoretical model was developed to access the thermal and electrical performance of the TEG system. The theoretical model consisted of the heat transfer mechanism including the thermal resistance networks from the flue gas to TEG and the heat sink. The electrical power output was determined using the Seebeck principle. The early stage of finding reveals that the system was able to produce an open circuit voltage of 0.13 V for a small temperature gradient of 3ᵒC between the cold and hot surface of the TEG. The further improvement of the system is currently under investigation for producing higher power. In the future, this system hopefully could replace the car battery for charging the alternator as well as increasing the overall efficiency of the engine system

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

    Full text link
    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

    Full text link
    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Experimental electrical characterisation of thermoelectric generator using forced convection water cooling / Raihan Abu Bakar...[et al.]

    Full text link
    Thermoelectric Generator (TEG) provides unique advantages as compared to other heat engines as it is capable to convert heat to electricity directly without having any moving parts. Furthermore, TEG is compact, simple and noiseless and requires very minimal maintenance. This paper presents an experimental and analytical study of a model consisting of a TEG located between a copper water cooling jacket and an aluminium block which acts as a heat spreader. The copper water cooling jacket was used in this study as water has higher thermal capacity than air. Besides, copper is one of highest thermal conductivity materials. TEG characterisation in term of electrical was investigated in this study. Based on the result, it shows a linear proportion relationship between open-circuit voltage and temperature difference across TEG. The result also clearly shows the power output of TEG increases as the temperature gradient across TEG increases. In addition, the impact of water flowrate on TEG power output was also studied. Based on the finding, there was an optimum water flowrate of 80 ml/s. Further increasing the water flowrate is not favourable as it will not increase power output and may lead to higher pumping power for water circulation. At this optimum water flowrate, the maximum power output obtained is equal to 530 mW when TEG hot-side temperature (Th) is 180 ℃

    Dispelling the Myths Behind First-author Citation Counts

    Full text link
    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

    No full text
    Nao informado

    Power generation using thermoelectric power generator with parabolic solar concentrator / Aneurin Nanggar Nyandang, Baljit Singh Bhathal Singh and Muhammad Fairuz Remeli

    Full text link
    Solar Thermoelectric Generator (STEG), a hybridization system of a thermoelectric generator (TEG) with a heat exchanger have been thoroughly explored because of its ability to produce both electricity and heat simultaneously. In this project, a STEG system consists of parabolic solar dish collector and a single TEG was constructed to produce both heat and electricity simultaneously. An absorber plate placed on the focal point of the dish was used to facilitate the heat transfer of the reflected solar radiation to the TEG through the plate. The absorber plate thickness was 1 mm and made up from copper to ensure high heat transfer rate and was well insulated to ensure minimal heat loss. To evaluate the performance of the STEG, Water-Cooled Cooling Method with Water Heat Sink and Air-Cooled Cooling Method (Forced-Convection) with Finned Heat Sink were introduced to cool down the generators. Results showed that Water-Cooled Cooling Method with Water Heat Sink was more effective to cool down the generator and allow a higher electricity being generated than air-cooled cooling method

    Assessing the impact of dual alcohol blends on diesel engine performance and exhaust emissions / Muhammad Fairuz Remeli, Muhammad Aiman Hakim Haron and Baljit Singh

    Full text link
    The increasing reliance on diesel fuel has heightened concerns about depleting fossil fuel reserves and environmental impacts. In response, researchers are exploring alternative fuel options, such as blends of alcohol and diesel, to improve sustainability. This study investigates the performance and emissions characteristics of several ethanol, methanol, and diethyl ether (DEE) blends with biodiesel and diesel. The tested fuel blends include B10 (90% diesel, 10% biodiesel), BDE (75% diesel, 10% biodiesel, 15% ethanol), BDE2DEE (75% diesel, 10% biodiesel, 15% ethanol, 2% DEE), BDE5DEE (75% diesel, 10% biodiesel, 15% ethanol, 5% DEE), and MBD2DEE (75% diesel, 10% biodiesel, 15% methanol, 2% DEE). Engine performance was evaluated in terms of brake-specific fuel consumption (BSFC), brake power, exhaust gas temperature, and mass and volume flow rates at varying engine loads. The results demonstrate that fuel blends with diethyl ether, particularly BDE5DEE, exhibited superior performance in reducing emissions. NOx emissions decreased by up to 16.2%, while CO2 emissions were reduced by 15.0%. Additionally, blends with diethyl ether lowered brake-specific fuel consumption by 30.7% compared to standard diesel (B10). The blend MBD2DEE, which includes methanol, delivered the highest brake power at higher loads (75%), peaking at 2.91 kW, indicating its strong potential for high-load applications. These findings suggest that dual alcohol-diesel blends, especially those containing diethyl ethers, offer a promising route for improving fuel efficiency and reducing harmful emissions, making them viable alternatives to traditional diesel fuel
    corecore