bluuebunny/crossref_metadata_2025_split huggingface dataset:
Integrating Concerns with Climate Change into Local Development Planning in Cambodia
Authors: Dany Va , Lebel Louis 
Published: January 2020

AbstractIntegration of climate change adaptation with development planning at multiple scales is widely seen as preferable to reactive, fragmented, or highly centralized responses. At the same time, there are growing concerns on when intervention is most appropriate, the transaction costs of coordination, and the adequacy of institutional capacity at local levels, especially in developing countries. This article examines entry points and mechanisms for integrating concerns with climate change into local development planning in Cambodia. An institutional ethnography of the planning process indicates that subnational planning is participatory and flexible; and thus, provides plausible entry points to integrate climate change concerns. Case study methods applied to two externally supported, climate‐resilient development projects identify promising mechanisms and strategies, as well as obstacles to integration. A vulnerability reduction assessment tool and top‐up grant scheme both included promising deliberative and participatory elements from which lessons for future and elsewhere can be drawn. At the same time, key stakeholders concede that local integration more widely is hampered by multiple obstacles, including weak institutional capacity, low community participation, and lack of resources and incentives. Addressing these challenges requires political commitments for good governance, capacity development, and additional resources.
Rent‐seeking, R&D, and productivity
Authors: Lai Yu‐Bong 
Published: January 2020

AbstractTo investigate whether rent‐seeking discourages productivity, we consider a third‐market model, in which a domestic firm and a foreign firm engage in both Research and Development (R&D) and output competition. We show that the relationship between rent‐seeking and productivity depends on two forces. On the one hand, rent‐seeking increases the marginal benefit of R&D and encourages productivity. On the other hand, a lower production cost due to R&D enables the government to extract the rent from the firm to a greater extent and discourages the productivity. Which force is dominant depends on the level of corruption or, as an alternative interpretation, the weight the government attaches to political contributions. Unlike the monotonic relationship proposed by the literature, we find a non‐monotonic relationship between rent‐seeking and productivity.
Effect of high nucleated cell concentration on product viability and hematopoietic recovery in autologous transplantation
Authors: Lin David Ming‐Hung , Hiskey Matthew , Huang Jane , Nickerson Cherie , Saisitthidej Desmond , Bradford Andrea , Woodburn Joshua , Lius Andrea , Skrzekut Adam , Tran Ellen , Haley Rebecca 
Published: January 2020

BACKGROUNDAdministering lower total product volumes with high nucleated cell (NC) concentrations may have the potential benefit of decreasing volume‐ and dimethyl sulfoxide (DMSO)‐related patient complications, while maximizing the laboratoryʼs freezer storage capacity. Our study is a retrospective investigation of the effect of HPC(A) products with cell concentrations greater than 3 × 108 NC/mL on clinical and product outcomes in patients undergoing autologous peripheral blood stem cell (PBSC) transplantation.STUDY DESIGN AND METHODSA total of 113 consecutive patients with hematological malignancies who underwent autologous PBSC transplantation were included in this retrospective analysis. The primary outcomes were days to initial absolute neutrophil count (ANC) recovery and initial platelet recovery. The secondary outcomes included the storage duration, segment thaw viability, and dose of viable CD34+ cells/kg administered.RESULTSOf 92 patients and 176 apheresis procedures, 81 patients received HPC(A) products with high NC concentration (4.1 × 108 NC/mL), and 11 patients received low NC concentration products (2.4 × 108 NC/mL). There were no observed differences in clinical outcomes with respect to ANC recovery (14 vs. 14 vs. 12 days) and platelet recovery (16 vs. 16 vs. 15 days) when very high NC (5.2 × 108 NC/mL) and high NC (4.1 × 108 NC/mL) groups were compared to the low NC group (2.4 × 108 NC/mL).CONCLUSIONOur retrospective investigation provides further supporting evidence that HPC(A) products with cell concentration greater than 3 × 108 NC/mL did not show detrimental effects on the clinical outcomes in patients undergoing autologous PBSC transplantation.
Preliminary Design of an All-Ceramic Discrete-Structure Particle Heating Receiver
Authors: Peters George , Golob Matthew , Nguyen Clayton , Jeter Sheldon , Danish Syed , Elleathy Abdelrahman , Al-Ansary Hany 
Published: January 2020

Abstract
Discrete structure particle heating receivers (DS-PHR), as used in concentrated solar power (CSP) systems, employ suitable discrete porous structures to intermittently halt the falling particles to control the speed and increase the residence time of falling particulates, thereby increasing the temperature rise of particulates exiting the DS-PHR. Previous designs of DS-PHRs have considered both porous foam structures, which have mass flux limits, and metal wire meshes, which are effective but have temperature and other functional limitations. This paper recounts recent studies at Georgia Tech and King Saud University that have investigated the use of ceramic tiles made porous by discrete slot-shaped passages in place of previous metal wire meshes. Currently, for experimental use, the slot-like passages are cut into the tiles by water jet, but operational units are expected to be formed into shape and fired by more economical conventional ceramic techniques. Benefits of ceramic and other refractory materials include higher temperature and heat flux limits at a reasonable cost. The tiles are expected to be installed in chevron configuration, which have been shown by experience to be especially effective, and these so-called ceramic chevrons have been shown to deliver adequate mass flux densities while still removing most of the kinetic energy from the particles. In addition, the thickness of the tile allows the incorporation of angled slots capable of redirecting the particle flow, adding a method to control particle mixing by purposefully directing the particulate streams. These enhanced slots are typically arranged with adequate spacing to allow for increased penetration of concentrated light into the depth of the falling bed of particles and may be angled to redirect hot particles toward the back plane of the DS-PHR. Both of these features should help minimize depthwise temperature variation. The testing reported here will focus on the degree of velocity and flow control that can be achieved by proper design of these ceramic chevrons as well as demonstrate the effectiveness of different designs on light penetration. Prior to this research, the effectiveness of ceramic obstructions might have been properly doubted because of the very high coefficient of restitution (COR) for the impact of ceramic particles on ceramic solids. In reality, it will be shown that a layer of particulates will form on a chevron, which effectively dissipates the kinetic energy of the impacting particles. Overall, this paper will report improvements in DS-PHR designs that can withstand high temperatures and fluxes, achieve additional control of particle flow, enhance particle mixing, and allow deeper penetration of light into the depth of the falling bed.
A Real-Time C3 Continuous Tool Path Smoothing and Interpolation Algorithm for Five-Axis Machine Tools
Authors: Hu Qin , Chen Youping , Jin Xiaoliang , Yang Jixiang 
Published: January 2020

Abstract
Local corner smoothing method is commonly adopted to smooth linear (G01) tool path segments in computer numerical control (CNC) machining to realize continuous motion at transition corners. However, because of the highly non-linear relation between the arc-length and the spline parameter, and the challenge to synchronize the tool tip position and tool orientation, real-time and high-order continuous five-axis tool path smoothing and interpolation algorithms have not been well studied. This paper proposes a real-time C3 continuous corner smoothing and interpolation algorithm for five-axis machine tools. The transition corners of the tool tip position and tool orientation are analytically smoothed in the workpiece coordinate system (WCS) and the machine coordinate system (MCS) by C3 continuous PH splines, respectively. The maximum deviation errors of the smoothed tool tip position and the tool orientation are both constrained in the WCS. An analytical synchronization algorithm is developed to guarantee the motion variance of the smoothed tool orientation related to the tool tip displacement is also C3 continuous. The corresponding real-time interpolation method is developed with a continuous and peak-constrained jerk. Simulation results verify that the maximum deviation errors caused by the tool path smoothing algorithm are constrained, and continuous acceleration and jerk of each axis are achieved along the entire tool path. Comparisons demonstrate that the proposed algorithms achieve lower amplitude and variance of acceleration and jerk when compared with existing methods. Experiments show that the proposed five-axis corner smoothing and interpolation algorithms are serially executed in real-time with 0.5-ms cycle.
Conductivity and Electrochemical Behavior of Plasticized Polymer Electrolyte for Dye-Sensitized Solar Cell Integrated Supercapacitor
Authors: Poojari Vidyashri , Devadiga Dheeraj , Hegde Niveditha , Sangeetha D. N. , Santosh M. S. , Selvakumar M. 
Published: January 2020

Abstract
The current energy situation requires not only enormous energy in a brief period of time but clean energy as well. In this direction, a dye-sensitized solar cell (DSSC)—supercapacitor (SC) integrated energy device has been fabricated. This embedded energy system has a specific advantage such as easy manufacturing, low manufacturing costs, and flexible substrates compatibility. A natural photosensitizer was extracted from readily available beetroots and characterized using ultraviolet (UV)-visible spectroscopy. The zinc oxide semiconductor was synthesized using microwave technique and regarded as the DSSC photoanode material. The ZnO’s phase, purity, and morphology were investigated using X-ray diffraction (XRD) spectroscopy and scanning electron microscope. The iodine-doped cellulose acetate propionate (CAP) biopolymer electrolyte functions as the DSSC and supercapacitor electrolyte. The solid polymer electrolyte conductivity and dielectric studies were performed using electrochemical impedance spectroscopy (EIS). The laser-induced technique was used to synthesize graphene that plays a dual purpose as photocathode in DSSC and supercapacitor electrodes. The embedded energy unit from the DSSC-supercapacitor demonstrates a 6.75% fill factor representing its decent efficiency.
Development of Film Cooled Thruster for Rocket Application
Authors: Kumar Avanish , Venkateswarlu V. , Satyaprasad P. , Rao M. Raghavendra 
Published: January 2020

Abstract
An experimental investigation has been carried out for small liquid bi-propellant thrusters of 490 & 1500 N levels. These thrusters have to operate for more than 100 sec in continuous and pulse mode. In this case, film cooling is the primary mode of thruster cooling. The thruster uses hydrazine based propellant as fuel and N2O4 as oxidiser. Film cooling is carried out by injecting a fraction of fuel from an injector periphery. Unlike impinging type injection elements are used for core flow. The thruster’s shell used for testing was made of stainless steel and di-silicide coated C103 material. A 1D heat transfer model was developed for predicting the thruster outer wall temperature. The experimental investigation was carried for different film cooling percentage and injector configuration was modified for each case. Thermocouples were mounted on top & bottom side of shell for temperature measurement. Infrared camera also used for recording temperature in the test. Based on experimental investigation, effective film cooling percentage for optimum thruster performance has been estimated for two thrust levels and these studies also helped in validating the heat transfer model.
Potential Applications of Fuel Cells for Hybrid Electric Aircrafts: Case Study
Authors: Kari Sreedhar , Thorne George , Szeki John , Hall Chris , Mortimer Lindsey , Gerbeth Robby 
Published: January 2020

Abstract
Increased greenhouse gas emissions have an adverse impact on climate change. Recently, there is an increased drive to reduce the emissions especially after the Paris agreement 2015. There are several research initiatives that have been started in the aerospace industry to reduce the emissions like NOx, CO2 and other harmful substances. This paper presents the case studies done on the potential applications of fuel cells for more electric aircrafts (MEA) to achieve the reduced emissions and reduced fuel consumption. The objective of this paper is to take a broad view of how fuel cell technology works, various types of existing technologies and their potential applications and challenges for aero engines in terms of power density.
In this study, the different types of fuel cells e.g. low temperature Proton Exchange Membrane (PEM) fuel cells and high temperature solid oxide fuel cells (SOFC) etc were studied and identified the opportunities and challenges to make them work for aero engines as a part of electrification. Different ways of storing the hydrogen on board have been explored. The comparison has been made with battery vs fuel cell power density including the H2 tank. The case studies were made for potential replacement of shaft power off take on civil large engines with fuel cells for hybrid long range aircrafts and regional propeller jets with fully electric power.
Savonius Wind Turbine Blade Profile Optimization by Coupling CFD Simulations With Simplex Search Technique
Authors: Agrawal Ankit , Kansagara Divyeshkumar D. , Sharma Deepak , Saha Ujjwal K. 
Published: January 2020

Abstract
The Savonius rotor, a drag-based vertical axis wind turbine, is characterized by its design simplicity, low noise level, self-starting ability at low wind speed and low cost. However, its low performance is always a major issue. One of the remedies of this issue is to design an optimized rotor blade profile, which has mostly been developed through trial and error approach in the literature. In this paper, an optimum blade profile is obtained by maximizing its power coefficient (CP) by coupling CFD simulations of a rotor blade profile with the simplex search technique. Since the blade profile is symmetric about its axis, half of the blade geometry is created through natural cubic spline curve using three points. Two of them are kept fixed, whereas the other one is changed through optimization technique in its every iteration using MATLAB platform. In every iteration, the blade profile is meshed using ANSYS ICEM CFD. The analysis of the blade profile is performed through ANSYS Fluent by using shear-stress transport k-ω turbulence model. A finite volume method based solver is used to solve the transient 2D flow around the wind turbine. The optimum profile of the blade is compared with the conventional profile over a wide range of tip speed ratios (TSRs) in order to check its feasibility for practical applications. The optimum blade profile is found to be better than the semicircular blade in the range of TSR = 0.6–1.
Control of Lean Blowout in Partially Premixed Swirl-Stabilized Combustor Using a Fuel Rich Central Pilot Configuration
Authors: De Somnath , Mondal Prasanna , Sardar Gourav Manohar , Bokhtiar Rakin Bin , Bhattacharya Arijit , Mukhopadhyay Achintya , Sen Swarnendu 
Published: January 2020

Abstract
The main problem for using reliable and stable diffusion combustion in modern gas turbine engines is the production of NOx at a higher level which is not permissible for maintaining the healthy environment. Thus, combustion in lean premixed mode has become the most promising technology in many applications related to power generation gas turbine, industrial burner etc. Although the lean combustion minimizes NOx production, it suffers from an increased risk of lean blowout (LBO) when the requirement of thrust or load is low. It mainly occurs at the lean condition when the equilibrium between the flame speed and the unburnt air-fuel mixture velocity is broken. Current aircraft gas turbine engines operate fuel close to the combustion chamber which leads to the partially premixed combustion. Partially premixed combustion is also susceptible to lean blowout. Therefore, we have designed a swirl-stabilized dump combustor, where different lengths of fuel-air mixing are available. Our present work aims at improving the combustion stability by incorporating a secondary fuel injection through a pilot arrangement connected with the combustion chamber for premixed as well as partially premixed flames. Incorporation of the pilot system adds a small fraction of the total fuel into the combustion chamber directly. This investigation shows significant extension of the LBO limit towards leaner fuel-air mixture while the NOx emission in the combustion chamber is within the permissible limit. This result can be used for aircraft operators during the process of landing when fuel supply has to be decreased to reduce engine thrust or for power plants operating at low loads. The study of control is based on the colour variation of the flame which actually defines the changes in combustion characteristics. For early detection of LBO, the ratio between the intensity of red and blue colour obtained from flame images with a high speed camera is used. As LBO is approached, the ratio of red to blue intensity falls monotonically. When the ratio falls below a preset threshold, a small fraction of the total fuel is added to the central pilot line. This strategy allows the LBO limit to be shifted to a much lower equivalence ratio (maximum 20% and 11% for fully premixed and least premixed flames, respectively) without any significant increase in NOx production. The analysis includes a feedback control algorithm which is computed in MATLAB and the code is embedded in Labview for hardware implementation.
Engine Ground Start Characteristics of Fighter Aircraft at High Altitude Airbase
Authors: Kasram Santhosh , Manoharan Sajath Kumar , Padwale Mahesh P. , Ravishankar G. P. 
Published: January 2020

Abstract
The challenges faced during starting of an aircraft gas turbine engine using a Jet Fuel Starter (JFS) at high altitude airbase are discussed in this paper. Autonomous ground starts at high altitude airbase in soaked sub-zero temperature condition without any external ground support assistance is a challenge. Generally, the start cycle (sub-idle speed) at sub-zero temperatures of a gas turbine engine at high altitudes is influenced by several factors. Drag loads are estimated due to change in lube oil viscosity of engine gearbox and accessory gear box that affects available torque margin of a starter. These estimated loads are superimposed on starter characteristics to identify the available margins for successful starts. The cold start is particularly severe, since it increases the tip clearance between rotor and casing of the engine due to difference in its thermal growth. Higher tip clearances significantly degrade compressor surge margin and results in rotating stall. Inconsistent engine starts were resolved by adopting alternative methods without any change in hardware. This paper presents set of methods used to overcome inconsistent engine starts at high altitude cold weather conditions.
Experimental Analysis of Combustion in Gas Turbine
Authors: Murthy M. S. N. , Kumar Subhash , Sreedhara Sheshadri 
Published: January 2020

Abstract
This paper presents the methodology and results of an experimental analysis of combustion in a gas turbine combustor. The experimental setup is designed to imitate the conditions of a working gas turbine engine (GT), using an actual gas turbine combustor. Air is supplied by a heavy-duty air compressor at a maximum pressure of 7 bar to the combustor through an air pipe catering to the developing length. The air flow rate is measured using an ASME standard Venturimeter along with a manometer. The air flow rate and pressure are controlled by a combination of air outlet valve placed before developing length and by a throttle orifice in the exhaust duct at combustor outlet. Diesel fuel used in the experiments is provided at required atomizing pressure by a gear pump. Mass flow rate and pressure of fuel is controlled by combination of valves and varying the speed of gear pump using a variable speed electric motor. Combustion is initiated in a conventional pilot ignition unit using a spark plug and fuel burner. Fuel flow rate is measured accurately using a unique catch and time measuring system at the inlet of the gear pump.
Effect of Stator Variability on Axial Compressor Performance
Authors: Purushothaman Kirubakaran , Naveen Kumar N. R. , Pandurangi Vidyadheesh , Pratap Ajay 
Published: January 2020

Abstract
Variability in stator vanes is a widely used technique to improve the stability and efficiency of axial flow compressor in gas turbine engines. Most of the modern aircraft jet engines use variable stator vanes in both low pressure and high pressure compressors primarily for off-design performance. This study discusses in detail about the effect of stator variability in a three stage low pressure axial compressor at design and off-design conditions. Computational flow analysis were carried out for the three stage low pressure compressor with variability in inlet guide vane and first stage stator blade. Detailed investigation on flow physics was carried out in rotor blade passages with stator variability. At off-design speeds, the reduction in flow velocity is lower than the reduction in blade tip speed. This leads to mismatch in flow angles and inlet blade angles causing high incidence and large flow separation in blade passage. This results in poor aerodynamic stability of the axial compressor at off-design speeds. In this study, aerodynamic performance of compressor is evaluated from 70% to 100% design speeds with different stagger angle setting of inlet guide vane at each speed. Further, to improve 2nd stage rotor performance, variability was introduced in 1st stage stator blade and performance was evaluated. Compressor test results are compared with CFD data for design and off-design speeds.