bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental Study on Performance of a Single-Cylinder Engine Fuelled With Diesel and Vegetable Oil-Diesel Blends
Authors: Banania Amarlo , Quiros Edwin N. , Mercado Jose Gabriel E. 
Published: December 2019

Abstract
Continuous demand for energy in order to provide to an ever-increasing global population calls for use of or integration of other alternative sources of fuel other than fossil fuels. Many countries all over the world use vegetable oils blended with neat diesel as alternative and using these biofuels can help alleviate lessen the emissions releases on the environment as well as the country’s dependency on fossil fuels. In the Philippines Coconut Methyl Ester (CME) is the primary vegetable oil used, however in this study we used four other vegetable oils which are RCO (Refined Corn Oil), RPO (Refine Palm Oil), JFO (Jahtropa Filtered Oil) and JME (Jathropa Methyl Ester) in order to investigate the possibility of their use in diesel engines. A 6.3 kW single-cylinder, four stroke cycle, direct injection engine was used for the study. This kind of engine is typically used in the Philippines for different purposes such as backup power for households, for boats, pumps and for agriculture use. The specific fuel consumption of the biodiesel blends compared to neat diesel fuel ranged from −15% to 15% with RCO and JME having higher SFC and JFO and RPO having lower SFC. Fuel conversion efficiency of the varied from −12% to 12% with JFO and RPO having higher efficiency and RCO and JME having lower efficiency. The power of the varied from −7% to 6% with RPO having lower power output, JFO having higher power output and JME and RCO having similar power output to neat diesel fuel. At full load condasition Neat Diesel Fuel blended with 15% Refined Palm Oil showed the greatest improvement in SFC while Neat Diesel Fuel blended with 10% Jathropa Filtered Oil showed the best power output.
A Study on Urban Heating System Flexibility: Modeling and Evaluation
Authors: Chen Jiaying , Huang Wei , Zhong Wei , Zhou Yi , Lin Xiaojie 
Published: December 2019

Abstract
This study develops a new perspective of analyzing urban heating system (UHS) by taking a looking at the heat transportation flexibility of the system. We proposed the heating system flexibility (HSF) concept to represent UHS’s capability of delivering heat to the substations (and the buildings) under different operation scenarios of valves and pumps. We also give out the corresponding evaluation method. Based on the proposed ideal and its quantification method, we take a real UHS as an example to show the effectiveness of HSF by investigating the impact of heating network topological structure change. When a topological change close to end user is introduced, the average flexibility increases but the median flexibility drops. We find that system-wide topological structure change such as new pipeline does not solve the imbalance of HSF among substations. Overall, the concept of HSF has the potential of being used as an important criterion in the design, operation, and control of future large-scale complex multi-source UHS.
GeoBMS for Better Building Energy Management
Authors: Krishnamurthy Karthik , Singh Pradeep , Sriraman Nikhil 
Published: December 2019

Abstract
Optimization of building energy usage presents an impactful and readily addressable industry opportunity. Commercial building operators have, over the past decade, invested in on-premise Building Management Systems (BMSs) to centrally monitor and operate building sensors and controllers. BMS configurations degrade over time due to changes in building occupancy patterns as well as from ongoing sensor and controller upgrades. Recent studies reveal that an additional 10% energy savings opportunity would be available if optimal BMS configurations were sustained.
Building operators face significant challenges in keeping BMS configurations optimized. The reasons are many. First, most BMSs offer proprietary interfaces that require custom, one-off integrations for remote access. Second, inconsistent BMS data representation makes it hard to aggregate and analyze performance data in order to operate systems with maximum efficiency. Third, BMSs are often designed as single user applications, creating complications to support multiple stakeholders that collectively dictate optimal usage.
We propose a hybrid cloud/on-premise model that addresses the limitations of current, on-premise BMS implementations and incorporates the benefits of new cloud technologies. Our hybrid model employs a cloud-based infrastructure “middle layer” (which we call GeoBMS) that connects the “top layer” of building performance applications with the “bottom layer” of existing brownfield BMS implementations. GeoBMS addresses BMS inaccessibility through virtualization; inconsistent data representation through common cloud data models; and lack of multi-stakeholder access through global authentication.
Through published APIs, GeoBMS enables the creation of innovative building performance applications. Applications use GeoBMS APIs to access previously unavailable on-premise BMS functionality and configuration data. We illustrate using a proof-of-concept application (which we call EnergyOptimize) that optimizes energy consumption for a museum case-example.
A Solid Oxide Fuel Cell-Gas Turbine Hybrid System for a Freight Rail Application
Authors: Ahrend Philipp , Azizi Ali , Brouwer Jacob , Samuelsen G. Scott 
Published: December 2019

Abstract
The simulation of a Solid Oxide Fuel Cell-Gas Turbine (SOFC-GT) hybrid system for a locomotive application is presented. Using Matlab Simulink, a 2.8 MW SOFC system was combined with a 500 kW GT and simulated to travel the route from Bakersfield to Mojave in California. Elevation data was imported using the Google API Console and smoothed in order to calculate the dynamic power demand for the SOFC-GT system, assuming 480 tons of freight per 120 ton locomotive traveling at an average speed of 45 mph. The SOFC-GT system model follows this demand without causing a significant disruption to the speed of the locomotive. A lithium-ion battery was included into the system model to improve the net system efficiency and make the operation smooth enough for the highly dynamic route. The overall efficiency along the simulated route has been calculated as 57% operating on partially pre-reformed natural gas fuel.
These results suggest the development of a physical prototype of the simulated system and are very promising for the future of freight rail transportation throughout the US. CO2 and particulate matter emissions are significantly reduced compared to current diesel-electric locomotives and it is also possible to operate the system on hydrogen, i.e., completely emission-free. A techno-economic analysis to assess the economic feasibility of this system is currently being prepared.
Life Cycle Assessment of Greenhouse Gas Emissions: Comparison Between a Cooling Tower and a Geothermal Heat Exchanger for Air Conditioning Applications in Ecuador
Authors: Porras Frank , Ramirez Angel D. , Walter Arnaldo , Soriano Guillermo 
Published: December 2019

Abstract
Cooling towers are widely used to remove heat in buildings with chilled water air conditioning systems. Moreira et al. [1] performed an experimental comparison between a cooling tower (CT) and a geothermal heat exchanger (GHE) in Guayaquil-Ecuador (hot/humid climate) and the results show an advantage of 39% of GHE systems regarding energy efficiency.
This study compares the emissions of greenhouse gases (GHG), considering the results of the research mentioned above and comparing both systems. A life cycle assessment (LCA) approach was used to estimate the GHG emissions, assuming three scenarios for the electricity supply: the electricity generation mix in 2016, the planned electricity generation mix in 2025, and the profile for marginal electricity generation (peak demand).
The estimated reduction of GHG emissions due to the use of GHE systems could be up to 50%. GHEs for building air conditioning applications is a technological option with potential to reduce energy consumption and GHG emissions. However, additional work is necessary to evaluate the complete environmental profile and its cost-effectiveness.
Performance of a Natural Gas Solid Oxide Fuel Cell System With and Without Carbon Capture
Authors: Iyengar Arun K. S. , Koeppel Brian J. , Keairns Dale L. , Woods Mark C. , Hackett Gregory A. , Shultz Travis R. 
Published: December 2019

Abstract
The fuel cell program at the United States Department of Energy (DOE) National Energy Technology Laboratory (NETL) is focused on the development of low-cost, highly efficient, and reliable fossil-fuel-based solid oxide fuel cell (SOFC) power systems that can generate environmentally-friendly electric power with at least 90 percent carbon capture. NETL’s SOFC technology development roadmap is aligned with near-term market opportunities in the distributed generation sector to validate and advance the technology while paving the way for utility-scale natural gas (NG)- and coal-derived synthesis gas-fueled applications via progressively larger system demonstrations. The present study represents a part of a series of system evaluations being carried out at NETL to aid in prioritizing technological advances along research pathways to the realization of utility-scale SOFC systems, a transformational goal of the fuel cell program. In particular, the system performance of utility-scale NG fuel cell (NGFC) systems with and without carbon dioxide (CO2) capture is presented.
The NGFC system analyzed features an external auto-thermal reformer (ATR) feeding the fuel to the SOFC system consisting of planar anode-supported SOFC with separated anode and cathode off-gas streams. In systems with CO2 capture, an air separation unit (ASU) is used to provide the oxygen for the ATR and for the combustion of unutilized fuel in the SOFC anode exhaust along with a CO2 purification unit to provide a nearly pure CO2 stream suitable for transport for usage in enhanced oil recovery operations or for storage in underground saline formations. Remaining thermal energy in the exhaust gases is recovered in a bottoming steam Rankine cycle while supplying any process heat requirements. A reduced order model (ROM) developed at the Pacific Northwest National Laboratory (PNNL) is used to predict the SOFC performance. The ROM, while being computationally effective for system studies, provides other detailed information about the state of the stack, such as the internal temperature gradient, generally not available from simple performance models often used to represent the SOFC. Such additional information can be important in system optimization studies to preclude operation under off-design conditions that can adversely impact overall system reliability. The NGFC system performance was analyzed by varying salient system parameters, including the percent of internal (to the SOFC module) NG reformation — ranging from 0 to 100 percent — fuel utilization, and current density. The impact of advances in underlying SOFC technology on electrical performance was also explored.
Performance Enhancement of Solar Air Conditioners Using Hybrid Heat Rejection System
Authors: Iqbal Abdul Ahad , Al-Alili Ali 
Published: December 2019

Abstract
The performance of air conditioning systems is highly dependent on the environmental conditions of the high pressure side, where heat is rejected to the environment. Air conditioning systems utilize dry cooling systems which often don’t provide adequate cooling during peak cooling periods, or wet cooling systems which consume a lot of water. In this study, a novel hybrid cooling system that can provide both wet and dry cooling was modelled in TRNSYS, and used to provide cooling to closed sorption air conditioning systems. The performance of these systems with the hybrid cooling system was compared to the performance of a standard vapor compression cooling system being cooled by a dry cooling system. The COPsol of the vapor compression cooling system exhibited a decrease of almost 26% during the summer period, whereas the COPsol of the sorption systems increased by around 30%. Similarly, the cooling capacity of the vapor compression cooling system dropped by almost 5%, and for the sorption systems, it increased by around 20% during the summer period.
Study of Different Types of Water Heating Systems - Under Living Lab Conditions
Authors: Dubey Swapnil 
Published: December 2019

Abstract
In Singapore, roughly 20% of the energy consumed by households is used for water heating and almost all the energy consumed by conventional electric water heaters. One of the significant potential energy saving opportunities lies in using energy-efficient water heating appliances. Recently, there has been a move towards energy-saving design and the use of natural refrigerants over fluorocarbons. Unlike conventional electric storage water heaters, which use electricity to heat water directly, heat pump storage water heaters use electricity only to operate a pump that circulates refrigerants around the system. This refrigerant collects heat from the surrounding atmosphere and transfers it to the water. CO2 heat pumps have low global warming potential when compared to other refrigerants based heat pumps, has zero ozone depletion potential, inexpensive, non-flammable, generate high temperature. In this project, a comparative analysis of three different water heater types has been presented based on real-time usage and living-lab conditions under the tropical climate of Singapore. These three types are:
1. Electrical heater storage type
2. Hybrid heat pump with auxiliary electrical heating water heater
3. CO2 heat pump water heater without auxiliary heating
Study found significant energy saving using CO2 heat pump compared to other water heating system and also better for environment.
Hydrogen and Compounds With Biological Activity From Microalgae
Authors: Rosa Marcos P. , Vargas Jose V. C. , Kava Vanessa M. , Dias Fernando G. , Savi Daiani , Santos Beatriz , Balmant Wellington , Mariano Andre B. , Servienski Andre , Ordóñez Juan C. 
Published: December 2019

Abstract
Microalgae have a high biotechnological potential as a source of biofuels (biodiesel, biohydrogen) and other high-added value products (e.g., pharmaceuticals, proteins, pigments). However, for microalgae cultivation to be economically competitive with other fuel sources, it is necessary to apply the concept of biorefinery. This seems to be the most ambitious strategy to achieve viability. Therefore, the objectives of this study were to isolate and identify the main microalgae line used to produce biofuels at Federal University of Parana, Brazil, using the rDNA sequence and micromorphological analysis, and to evaluate the potential of this lineage in the production of hydrogen and co-products with biological activity. For the purification of the lineage (LGMM0001), an aliquot was seeded into solid CHU culture medium and an isolated colony was selected. The genomic DNA was purified using a commercial kit (Macherey-Nagel, Düren, Germany) for molecular identification, the ITS region (ITS1, 5.8S and ITS2) (Internal Transcribed Spacer) was amplified and sequenced using primers LS266 and V9G. Morphological characterization was performed as described by Hemschemeier et al. [1]. Finally, for biological activity research, secondary metabolites were extracted by fractionation and evaluated against bacteria of clinical interest. Through microscopic analysis, general characteristics shared by the genus Tetradesmus were observed. The plasticity of the morphological characteristics of this genus reinforces the need for further studies to classify correctly the species in this group, using DNA sequencing. ITS sequence analysis of LGMM0001 showed 100% homology with sequences from the Tetradesmus obliquus species, so, the lineage was classified as belonging to this species. The evaluated microalgae strain was able to produce hydrogen, showing positive results for gas formation. Biological activity was observed with the extract obtained from the residual culture carried out with alternative medium used in the photobioreactors (PBR), against the Staphylococcus aureus pathogenic lineage. In conclusion, the microalgae strain used in this work was identified as Tetradesmus obliquus (= Acutodesmus obliquus), and was able to produce a compound with economic potential in association with the existing biofuel production process.
Dynamic Impedance Monitoring of Large Diameter-Vessel Sealing in Bipolar Electrosurgeries
Authors: Li Xiaoran , Yang Che-Hao , Chen Roland K. , Li Wei 
Published: December 2019

Abstract
Vessel sealing with a bipolar electrosurgical device has become a common practice in modern operation rooms. Despite all the advantages, such as easier operation, less bleeding, and shorter post-surgery recovery time, side effects including sticking, charring, and rebleeding, often occur, leading to increased operation time and sometimes complications that are potentially fatal. Tissue impedance during the electrosurgical procedure has been used to improve the surgical outcome However, this method has only been effective for small-diameter vessels of 3–5 mm. Overall, little is found in literature on dynamic impedance monitoring of blood vessel sealing using bipolar electrosurgical devices. In this study, an experimental setup was designed and built to perform vessel sealing tests on large-diameter blood vessels with mimicking blood flow. Ex vivo porcine carotid artery samples with a diameter about 7 mm were used. Burst pressures after sealing were measured. It was found that the tissue impedance started with an initial decrease, followed by a rapid increase, and ended with a plateau that was orders of magnitude higher than the initial impedance. The rapid increase of impedance provides indication of protein denaturing, thus the seal completion. This feature was used to monitor the electrosurgical vessel sealing process. It is shown that a burst pressure at least twice the normal human systolic blood pressure can be achieved with heating until the maximum tissue impedance is reached. A FEA model was developed in COMSOL to understand the dynamic impedance behavior in the vessel sealing process.
The Oriented Spray Cooling System for Heat Rejection and Evaporation
Authors: Bowman Charles F. , Taylor Robert E. , Hubble Jerry D. 
Published: December 2019

Abstract
Spray ponds offer significant advantages over mechanical draft cooling towers (MDCT) including superior simplicity and operability, lower preferred power requirements, and lower capital and maintenance costs. Unlike a conventional spray pond in which spray nozzles are arranged in a flat bed and water is sprayed upward, the Oriented Spray Cooling System (OSCS) is an evolutionary spray pond design in which nozzles are mounted on spray trees arranged in a circle and are tilted at an angle oriented towards the center of the circle. As a result, each nozzle is exposed to essentially ambient air as water droplets drag air into the spray region while the warm air concentrated in the center of the circle rises. Both of these effects work together to increase air flow through the spray region. Increased air flow reduces the local wet-bulb temperature (LWBT) of the air in the spray pattern, promoting heat transfer and more efficient cooling. The authors have developed analytical models to predict the thermal performance of the OSCS that are based on classical heat and mass transfer and kinetic vector relationships for spherical water droplets that rely only on generic experimental thermal performance data. Therefore, the model is not limited in application with regard to spray pressure or nozzle spacing or orientation and is not limited by droplet size considerations. This paper describes specific details such as nozzle type, orientation, and drop spectrum and details on the analytical model never before published that are used to predict the OSCS performance. The paper compares the predicted performance of the OSCS with the rigorous full-scale field test results that were measured in compliance with Nuclear Regulatory Commission requirements at the Columbia Generating Station (CGS) where the ultimate heat sink (UHS) is two OSCS.
Study on a New Solar Thermal Energy Complementary Power Generation System Based on Gas-Steam Combined Cycle
Authors: Liqiang Duan , Zhipeng Lv , Zhen Wang 
Published: December 2019

Abstract
The integrated solar energy-driven chiller combined cycle system (SCCC) has a problem of low annual solar energy utilization. The solar thermal efficiency and power output of the traditional integrated solar combined cycle system (ISCC) are limited by the integrated solar mirror field area and Rankine cycle efficiency. This paper presents a new system, on the basis of the combined cycle system with the three pressure HRSG with reheat, the solar energy is integrated into the chiller for cooling the compressor inlet air of gas turbine and the heat recovery steam generator (HRSG) for increasing the power output simultaneously. The Aspen Plus, TRNSYS and EBSILON softwares are applied in this paper to build the models of the overall system. The solar thermal efficiency, annual solar power generation and annual solar thermal efficiency are used to evaluate the performances of the new system, the traditional ISCC system and SCCC system. During the summer solstice, the proportions of solar energy used in cooling and heating are set as 40% and 60% in new system, respectively. The research results show that the new system has a higher power output (406.37MW), thermal cycle efficiency (53.61%) and solar thermal efficiency (48.85%) compared with the traditional ISCC system (385.63MW, 51.67%, and 24.43%, respectively) at the design point. The new system can regulates the proportions of solar energy used in the chiller and HRSG based on the monthly meteorological data, in order to maximize the annual solar energy utilization and annual solar power generation. The new system’s annual solar energy utilization hours (2071h) and solar power generation (25.863GW·h) are far greater than those of SCCC system (1498h, 18.185GW·h, respectively). Therefore, the proposed new system with the simultaneous integrations of solar energy with both the chiller and HRSG not only greatly increases the utilization rate of solar energy, but also has the significant thermodynamic advantages.
Time-of-Use Pricing in the Electricity Market: An Application of Stackelberg Game
Authors: Ketkar Atharva , Koonamparampath Joselyn , Sawant Mayur 
Published: December 2019

Abstract
Electrical power, generated and consumed, is perhaps, one of today’s most important construct in determining the progress of a people. The power mismatch between the generated and consumed power is one of the major issues faced in the electricity industry. This can be addressed by analysing user behaviour and manipulating it. This paper attempts to put forth a demand response (DR) technique using the concept of Time-of-Use (ToU) electricity pricing. The utilities have an upper hand of quoting the electricity price whereas the users must follow this price and give their best response of power consumption. This process is similar to a leader-follower setting as in a Stackelberg game where the follower acts according to the leader’s strategy and gives its best response in every situation. This paper proposes a pricing technique where the users are charged according to the amount of power consumed in the specific period of time.