bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automatic facial pore analysis system using multi‐scale pore detection
Authors: Sun J. Y. , Kim S. W. , Lee S. H. , Choi J. E. , Ko S. J. 
Published: November 2016

Background/purposeAs facial pore widening and its treatments have become common concerns in the beauty care field, the necessity for an objective pore‐analyzing system has been increased. Conventional apparatuses lack in usability requiring strong light sources and a cumbersome photographing process, and they often yield unsatisfactory analysis results. This study was conducted to develop an image processing technique for automatic facial pore analysis.MethodsThe proposed method detects facial pores using multi‐scale detection and optimal scale selection scheme and then extracts pore‐related features such as total area, average size, depth, and the number of pores. Facial photographs of 50 subjects were graded by two expert dermatologists, and correlation analyses between the features and clinical grading were conducted. We also compared our analysis result with those of conventional pore‐analyzing devices.ResultsThe number of large pores and the average pore size were highly correlated with the severity of pore enlargement. In comparison with the conventional devices, the proposed analysis system achieved better performance showing stronger correlation with the clinical grading.ConclusionThe proposed system is highly accurate and reliable for measuring the severity of skin pore enlargement. It can be suitably used for objective assessment of the pore tightening treatments.
Performance Analysis of Innovative Top Cooling Thermal Photovoltaic (TPV) Modules Under Tropics
Authors: Dubey Swapnil , Soon C. S. , Chin Sin Lih , Lee Leon 
Published: November 2016

The main focus area of this research paper to efficiently remove the heat generated during conversion of solar energy into electricity using photovoltaic (PV) module. The photovoltaic conversion efficiency of commercial available PV module varies in the range of 8%–20% depending on the type of solar cell materials used for the module construction, e.g. crystalline silicon, thin film, CIGS, organic, etc. During the conversion process, only a small fraction of the incident solar radiation is utilize by PV cells to produce electricity and the remaining is converted into waste heat in the module which causes the PV cell temperature to increase and its efficiency to drop. This thermal energy could be extract using air or water as a heat removal fluid to utilize in heating applications. The purpose of a solar photovoltaic module is to convert solar energy into electricity. The hybrid combination of photovoltaic module and thermal collector called Photovoltaic-thermal (PVT) module. Such PVT module combines a PV, which converts electromagnetic radiation (photons) into electricity, with a solar thermal module, which captures the remaining energy and removes waste heat from the PV module. Cooling of cells either by natural or forced circulation can reduce the PV cell temperature. The simultaneous cooling of the PV cells maintains their PV efficiency at a satisfactory level and offers a better way of utilizing solar energy by generating thermal energy as well. PVT system has higher overall efficiency as compared to separate PV and thermal collector. The heat output of a PVT module can be used for space heating or production of domestic hot water.
This paper presents an innovative design of top cooling Thermal Photovoltaic (T-PV) module and its performance under outdoor weather condition of Singapore. T-PV collector is designed to flow fluid over the top of PV panel through a very narrow gap between the solar lens. This process improves heat removal process from PV panel, and hence, improves the electrical output of PV panel as compared to other PVT collector available in the market. By flowing the water from top of the PV panel will also provide better thermal efficiency. A T-PV collector system with storage tank, sensors, pump, flow meters, data logger and controls, have been installed at test-site located in Ngee Ann Polytechnic, Singapore. Performance analysis of T-PV collector system has been evaluated under the tropical climatic conditions of Singapore. It was found that T-PV module could produce additional electrical power as compared to standard PV panel of same capacity by operating at lower temperature. In addition to electricity, T-PV panel also generate the hot water up to 60 deg C at an average thermal efficiency of 41% for usage in residential and commercial buildings. The average thermal energy output was 3.1 kWh/day on typical day’s basis.
HTR-PM Technology in Energy Supply of Petrol Chemical Industry in China: An Economic Feasibility View
Authors: Zhao Gang , Ye Ping , Wang Jie , Yang Xiaoyong 
Published: November 2016

The massive use of fossil fuel has caused huge carbon emission and serious air pollution in China. Now all kinds of alternative energy technology are developing rapidly to solve such problem in China. Electricity produced by non-fossil fuel energy is continued to increase sharply in China. But it’s hard for regular alternative energy, such as wind power, solar power, hydroelectricity power, nuclear power and so on, to easily provide process heat for industry, especially high temperature steam.
High temperature Gas-cooled Reactor (HTGR, sometimes also called HTR) is a kind of nuclear reactor, which are demonstrated very high efficiencies, safety and availability features by American and German power plant. HTR differs from water nuclear reactors by offering a high thermal efficiency for electricity generation and a high level of passive safety features. Now HTR-PM project is built in Shidao Bay of China. Moreover, HTR is the only nuclear reactor, which can provide high temperature steam comparing with other water nuclear reactors. So HTR can provide a versatile cogeneration solution for industry.
In this paper, a case was studied, how to provide heat for a refinery and petro-chemical plant with HTR. Firstly, the energy need of a typical large chemical plant in china was investigated. Steam supply diagram of an oil refinery plant, which produced 10 million tons oil products and 1 million tons ethylene in China, was calculated. Secondly, technical feasibility of energy providing by HTR cogeneration plant was discussed. Extraction steam from HTR system was designed for the chemical plant. It would meet the requirement of steam supply for chemical plant and would replace the captive power plant, where coal was burning. The balance of steam, enthalpy and temperature was calculated. At last, economic evaluation for such cogeneration plants was carried out. The steam supply cost from captive coal power plant and HTR cogeneration plant was compared. Some economical conclusion was made from the discussion.
Thermodynamic Model of a Solar Receiver for Superheating of Sulfur Trioxide and Steam at Pilot Plant Scale
Authors: Guerra Niehoff Alejandro , Thomey Dennis , Romero Gonzales Moises A. , Streber Hans-Peter , Lapp Justin , Roeb Martin , Sattler Christian , Pitz-Paal Robert 
Published: November 2016

Within the European research project SOL2HY2, key components for a solar hybrid sulfur cycle are being developed and demonstrated at pilot scale in a real environment. Regarding the thermal portion, a plant for solar sulfuric acid decomposition is set up and initially operated at the research platform of the DLR Solar Tower in Jüulich, Germany.
One major component is the directly irradiated volumetric receiver, superheating steam and SO3 coming from a tube-type evaporator to above 1000 °C. At the design flow rate of sulfuric acid (50%-wt.) of 1 l/min, a nominal solar power of 57 kW is required at the receiver. With a flat ceramic absorber made from SiC and a flat quartz glass window, the design is based on lab scale reactors successfully demonstrated at the solar furnace of the German Aerospace Centre (DLR) in Cologne, Germany.
A flexible lumped thermodynamic tool representing the receiver, compiled to assess different configurations, is presented in detail. An additional raytracing model has been established to provide the irradiation boundaries and support the design of a conical secondary concentrator with an aperture diameter of 0.6 m. A comparison with first experimental data (up to 65% nominal power), obtained during initial operation, indicates the models to be viable tools for design and operational forecast of such systems. With a provisional method to account for the efficiency of the secondary concentrator, measured fluid outlet temperatures (up to 1000 °C) are predicted with deviations of ±60 °C. Respective absorber front temperatures (up to 1200 °C) are under-predicted by 100–200 °C, with lower deviations at higher mass flows. The measured window temperature (up to 700 °C) mainly depends on the absorber front temperature level, which is well predicted by the model.
Solar Net Metering Increases Utility-Supplier Profit Margins
Authors: Flarend Richard 
Published: November 2016

Net metering is an incentive that is essential to most solar photovoltaic systems. Recently the burden placed upon local utilities is an issue some regulators have been asked to address. This research uses actual 2013 and 2014 solar production data from nearly 200 sites, wholesale electricity day-ahead pricing data, and utility-wide demand data. This is all analyzed by the hour for two full years for a western Pennsylvania based utility and an eastern Pennsylvania based utility and their wholesale generators. Results show electricity is 15% more valuable when solar PV systems are generating power and feeding the grid during good weather conditions than at night or cloudy days when solar customers get energy back from the grid.
Solar energy generation is highly predictable in the day-ahead market, and leads to suppression in market prices for electricity. Thus to reveal the true impact of this market suppression, an increased solar renewable portfolio standard (RPS) fraction of 0.2 to 10% was simulated. This caused a decrease in demand resulting in a corresponding reduction in the price of electricity yielding savings to the utility. The maximum rate of increase and decrease in the utility-wide load did not change significantly until the solar RPS exceeded 5%. Additionally, the demand for electricity was reduced during the highest load hours of the year that corresponded to the most expensive hours of the year. The minimum base-load of the year was decreased substantially for solar RPS of 5% or greater and the base load reaches zero for solar RPS over 10%.
From the data of these two years, it is demonstrated that an increased use of solar energy would lead to savings that are larger than the loss in revenue due to having fewer traditional non-solar customers. Thus electricity suppliers and utilities stand to have both higher profits and higher profit margins when customers adopt net-metered solar energy compared to the non-adoption of solar energy.
Mapping Energy Storage Physics to Application Economics
Authors: Berry Irene , Merfeld Glen , Riley Patrick 
Published: November 2016

The success of grid scale energy storage hinges on our ability to solve real problems economically. By mapping energy storage physics to application economics, this paper offers a technology neutral look at how energy storage can solve real problems.
A value analytics methodology was developed that combines the physics of energy storage, application power commands, and market-specific economic constructs. This approach evaluates and optimizes the value of energy storage for specific projects by providing insight into the tradeoffs between the lifecycle costs and revenues. These analytics calculate the net present value (NPV) and internal rate of return (IRR) of select energy storage assets, markets, and applications by considering these key factors:
• Duty profiles and control strategies
• Market economics and revenue streams
• Asset performance at cell, module, and system levels
• Price projections including balance of plant (BOP)
• Cycle and calendar life
• Project length and financing terms
The value analytics methodology combines three model streams. The first takes a high fidelity load profile (for example, the power output of a building, wind turbine, or solar farm), imposes a specific control strategy, and calculates revenue streams in a selected market. From this first model stream a storage power command is generated. This power command is fed into the second model stream that calculates the required size and price of a given storage type. Finally, a third model stream uses empirical life models to calculate degradation rates, replacement intervals, and maintenance costs. These are rolled up into a project specific financial analysis that forecasts project NPV and IRR.
The underlying engine for this methodology is a large performance and price database of over 100 commercial and emerging energy storage assets that spans a wide range of technologies from ultracapacitors and flywheels to lead acid and lithium-ion batteries. The physics based performance of each asset is captured as an equivalent circuit model. These models are exercised to create performance envelops that describe the rate dependent power capability as a function of the type, amount, and age of installed storage.
The energy storage value analytics described in this paper can be used to test key sensitivities. This methodology has been applied to standalone energy storage systems as well as the combination of energy storage with renewables and distributed power generation. As shown, the methodology is relevant for an even wider range of applications. Several solution maps will be shared that reveal, by market segment, the energy storage type, amount, and application that create the greatest customer value. This type of informed design and dispatch will solve real problems, create new value streams, and open new markets for grid scale energy storage.
Lightweight System Design Optimization of High Reliability Compact Air Independent PEMFC Power Systems for Aerial and Space Vehicles
Authors: Utz Robert , Wynne Bob , Ferguson Scott , Miller Mike , Sievers Bob , Song Ying 
Published: November 2016

Demand has increased for high reliability mobile power systems for space and aerial vehicles in military, scientific, and commercial applications. Batteries have traditionally supplied power in these applications, but the desire to extend mission duration and expand vehicle capabilities would require an energy density increase that is difficult for batteries to achieve. The use of pure hydrogen and oxygen reactants with high efficiency membrane electrode assemblies and novel design concepts for the fuel cell stack bipolar plates and balance of plant (BOP) components has the potential to meet the desired system energy density.
This paper reviews subsystem and integrated testing of a lightweight PEM fuel cell system design for implementation into an aerial vehicle or space mission. The PEM fuel cell stack is designed for optimum efficiency at 2 kWe of power during standard operation with the capacity to provide over 5 kWe of continuous power. The passive flow control and water management subsystems provide the gas flow and humidification necessary for efficient operation and remove excess water produced by the stack under all operating regimes. Work is in progress to test the fully integrated system under expected operating conditions for potential lightweight PEMFC applications.
Guidelines and Techniques for the Effective Control of Condensate Dissolved Oxygen in Steam Surface Condensers
Authors: Nightingale Darren M. 
Published: November 2016

Low levels of dissolved oxygen for the condensate produced within steam surface condensers is highly desirable and an increasingly important performance metric related to the efficient operation of today’s power plants. The presence of high levels of dissolved oxygen within condensate can quickly contribute to; accelerated corrosion, the need for additional treatment requirements, increased maintenance, operational challenges and even early equipment failure.
Under certain operating conditions, steam surface condensers can be expected to produce condensate with defined and/or guaranteed levels of dissolved oxygen. However, these levels can only be achieved provided certain guidelines are maintained and operational limitations are not exceeded. This is not always the case.
This paper includes the latest design guidelines, operational limitations, general considerations and practical techniques for controlling and minimizing condensate dissolved oxygen levels produced within steam surface condensers.
Hydraulic Model Calibration of a Nuclear Plant Service Water System
Authors: Onat Erin A. , Walters Trey W. , Mobley David M. , Mead James J. 
Published: November 2016

As pipe networks age, build-up [scaling] and corrosion decrease pipe diameter and increase pipe roughness, leading to significant pressure drops and lower flow rates. When modeling the hydraulics of these systems, calibrating the pipes to account for additional scaling and/or fouling can be vital to accurately predicting the hydraulic behavior of the system.
An automated, multi-variable goal-seeking software was used to calibrate the raw water system of the Duke McGuire Nuclear Station (MNS). This calibration process involved three phases. The first phase was the testing of the automated, multivariable goal-seeking software on a previously calibrated system. The second phase was the calibration of a partial data set. The third phase was the calibration of a complete data set. The automated goal-seeking software was found to have varying degrees of success in each phase.
At the conclusion of the calibration process, the partial data calibration of two parallel systems at MNS yielded average overall calibration accuracies of 2.1% and 1% for flow rates, and 1.2 psig (8.4 kPa-g) and 1.7 psig (11.9 kPa-g) for pressures. The complete data calibration of one of these systems at MNS yielded an average overall calibration accuracy of 2.3% for flow rates, and 1.4 psig (9.5 kPa-g) for pressures.
Challenges in Meeting the Electricity Needs of South Africa
Authors: Roy-Aikins Joseph 
Published: November 2016

The state-owned power utility, Eskom, generates about ninety five percent of the electricity produced in South Africa. Plans by the government of South Africa in the mid-nineteen nineties to restructure the electricity industry in the country prevented Eskom from embarking on capacity expansion activities when it was necessary. Load growth, as a result of economic growth and a national electrification programme, caused an erosion of the electricity reserve margin, which was quite massive in the early nineties. The large reserve margin then caused Eskom to reduce operating capacity by mothballing some generating plants and putting them in reserve storage.
The current situation is that the reserve margin has dropped to about 17,4 percent and a capacity expansion programme is underway. Though the apparent reserve margin is within the desired range, plant unavailability has diminished the reserve margin in real terms and this does not leave Eskom with much room for planned maintenance and a buffer to manage unplanned maintenance, the result being that plant incidents and technical problems cannot easily be absorbed within the power system to avoid interruption of supply. Also, the new environmental legislation does not help the situation, as it has the potential to shut down generating plants that do not meet the new emissions standard. In addition, there have been problems with the New Build Programme that caused a delay, of over three years, in the delivery of new power, and to compound the problem the Energy Regulator refused recently Eskom’s application for additional tariff increase, which was requested to enable the company provide the finances to cover the shortfall in funding for operational expenses and the New Build Programme. As such, Eskom faces many challenges in meeting its obligation to South Africa, and interventions are in place to manage the situation. In the short term, the key to generation sustainability is improved plant health, brought about by on-time maintenance and correctly-scoped and no-slip outages.
This paper presents an overview of the power situation in South Africa, explaining where the country has come from, the plan for long term security of supply, and the challenges faced by Eskom from the generation supply side in meeting the demand load in the short term. Trends in the performance indices indicative of plant health are examined and it is argued that executing planned plant maintenance will improve plant health and, hence, plant availability, which can bring about a turnaround in the short term power supply situation, as Eskom awaits new capacity from the New Build Programme.
Pool Boiling Heat Transfer Enhancement With Structured Surfaces
Authors: Dikici Birce , Al-Sukaini Basim Q. A. 
Published: November 2016

With the increasing power of electronic devices in recent years, thermal management has become an obstacle in scaling down chip designs. Direct liquid cooling is a great option for heat dissipation from high powered electronic systems due to its ability to remove large amounts of heat [1–2].
The aim of this study is to investigate pool boiling performance of water under atmospheric pressure by using structured surfaces. Surfaces with rectangular channels, holes, and mushroom fins are manufactured and tested. The results showed that boiling heat transfer can be enhanced by macroscopically structured surfaces.
Heat transfer coefficient (h) enhancement ranged between 23–44% for structured surfaces compared to plain surface. Heat flux is varied in the range of 16–18kW/m2. The maximum enhancement in heat transfer coefficient is ranged between 39–44.4% measured by 405 holed surface compared to the plain surface. The measured excess temperature drops ranged between 12–34% for different surfaces compared to plain surface. The excess temperature dropped around 29–34% for 405-holed surface compared to the plain surface.
As the spacing between channels or holes is decreased, the heat transfer coefficient is increased. Base temperature measurements are carried out using an Infrared Camera. A digital camera was used to record pool boiling phenomena and evaluate bubble dynamics. The bubbles with holed surfaces and mushroomed surface observed to have almost spherical shape, while in plain and grooved surfaces they have an irregular shape.