Simultaneous Spectral Imaging of C2*/CH* at Low-to-High Pressure Combustion

Author(s):  
Jonathan Reyes ◽  
Kareem Ahmed

This paper presents the correlation of the intensity ratio of the C2* and CH* radicals to fuel-air measurements over a range of pressures using 93% octane gasoline as the fuel. The measurements are conducted for the first time at high pressures. The study utilizes beam splitting technology to simultaneously view C2* and CH* as a line of sight, global measurement at the cost of resolution. A heavily instrumented constant volume combustor, with optical access, was employed to acquire the data. The ratio of C2* and CH* has been proven to be a good index of the equivalence ratio of premixed laminar flames. This index is attained, quite simply, by filtering each at their respected emissive peaks and taking the ratio of C2* over CH*. This technique shows great promise for use in turbomachinery as it will allow for identification of rich and lean locations in a combustor. By knowing the fuel-air field, combustor inefficiencies can be addressed to allow for greater energy release in combustion. The issue lies with the application of the indexing technique. Presented data to date has been performed on laboratory based diffusion flames exhausting to atmosphere, or premixed, steady, combustor type flames at low pressure (1atm) conditions. These types of flames are not relevant for engine combustor conditions. Understanding the fuel distribution at relevant regimes will reveal where inefficiencies may lie in injector or combustor design. Propagating flame kernels pose a problem in that they do not produce as much light as a steady flame, this makes spectral data difficult to obtain. Steady flames also do not address the effects that pressure may have on the index of C2* and CH*. The authors of this work seek to address three main issues associated with the indexing technique: The feasibility of its application to combustors (hardware design), The ability to operate at low-light ignition events, and the effects pressure may have on the correlation of intensity ratio to the fuel-air measurement.

2017 ◽  
pp. 34-47
Author(s):  
Hoi Le Quoc ◽  
Nam Pham Xuan ◽  
Tuan Nguyen Anh

The study was targeted at developing a methodology for constructing a macroeconomic performance index at a provincial level for the first time in Vietnam based on 4 groups of measurements: (i) Economic indicators; (ii) oriented economic indicators; (iii) socio-economic indicators; and (iv) economic - social – institutional indicators. Applying the methodology to the 2011 - 2015 empirical data of all provinces in Vietnam, the research shows that the socio-economic development strategy implemented by those provinces did not provide balanced outcomes between growth and social objectives, sustainability and inclusiveness. Many provinces focused on economic growth at the cost of structural change, equality and institutional transformation. In contrast, many provinces were successful in improving equality but not growth. Those facts threaten the long-term development objectives of the provinces.


Author(s):  
Leonardo Donatti ◽  
Andre Carlos Contini ◽  
Cristian Alex Hoerlle ◽  
Leonardo Zimmer ◽  
Lisandro Maders ◽  
...  

Author(s):  
Mark Blaxill ◽  
Toby Rogers ◽  
Cynthia Nevison

AbstractThe cost of ASD in the U.S. is estimated using a forecast model that for the first time accounts for the true historical increase in ASD. Model inputs include ASD prevalence, census population projections, six cost categories, ten age brackets, inflation projections, and three future prevalence scenarios. Future ASD costs increase dramatically: total base-case costs of $223 (175–271) billion/year are estimated in 2020; $589 billion/year in 2030, $1.36 trillion/year in 2040, and $5.54 (4.29–6.78) trillion/year by 2060, with substantial potential savings through ASD prevention. Rising prevalence, the shift from child to adult-dominated costs, the transfer of costs from parents onto government, and the soaring total costs raise pressing policy questions and demand an urgent focus on prevention strategies.


2021 ◽  
Vol 1 ◽  
pp. 131-140
Author(s):  
Federica Cappelletti ◽  
Marta Rossi ◽  
Michele Germani ◽  
Mohammad Shadman Hanif

AbstractDe-manufacturing and re-manufacturing are fundamental technical solutions to efficiently recover value from post-use products. Disassembly in one of the most complex activities in de-manufacturing because i) the more manual it is the higher is its cost, ii) disassembly times are variable due to uncertainty of conditions of products reaching their EoL, and iii) because it is necessary to know which components to disassemble to balance the cost of disassembly. The paper proposes a methodology that finds ways of applications: it can be applied at the design stage to detect space for product design improvements, and it also represents a baseline from organizations approaching de-manufacturing for the first time. The methodology consists of four main steps, in which firstly targets components are identified, according to their environmental impact; secondly their disassembly sequence is qualitatively evaluated, and successively it is quantitatively determined via disassembly times, predicting also the status of the component at their End of Life. The aim of the methodology is reached at the fourth phase when alternative, eco-friendlier End of Life strategies are proposed, verified, and chosen.


Author(s):  
Gustavo A Ballen ◽  
Mario C C De Pinna

Abstract A standardized terminology for the anatomy of pectoral- and dorsal-fin spines in the order Siluriformes is proposed based on an extensive literature review and direct examination of representatives of the order. The adult anatomy of the spines is described in detail. Terminology of various spine parts are reviewed and standardized, each term provided with a synonymic list organizing previous usage. Most of the structures treated have been recorded and named in the literature, but some are herein named for the first time. A quantitative approach is proposed for orienting decisions on name usage, aiming at minimizing differences between the terminology proposed and the vast amount of pre-existing literature, herein called the cost function. It is expected that this system will aid efforts in organizing the chaotic anatomical nomenclature of the appendicular skeleton in Siluriformes, and provide a solid basis for advances in comparative anatomy and nomenclature. The proposed terminology system has potential application on a number of fields that utilize information from catfish spines, ranging from taxonomy to phylogenetic systematics to paleontology and archaeology.


2021 ◽  
Vol 227 ◽  
pp. 52-64
Author(s):  
Lei Feng ◽  
Qianlong Wang ◽  
Haifeng Liu ◽  
Yanqing Cui ◽  
Zhi Yang ◽  
...  

2021 ◽  
pp. 227853372110083
Author(s):  
Smita Mukherjee ◽  
Zubin R. Mulla

We examine the cost of leaders changing between empowering and directive leadership styles on team outcomes. In a laboratory experiment, we collected data from 240 participants in 80 teams. Confederates enacted different leadership styles and led teams of participants in performing a series of tasks. When leaders changed their style from directive to empowering, teams took time to respond in terms of higher satisfaction with leader and affective commitment. However, when leaders changed their style from empowering to directive, the deterioration of satisfaction with leader and reduction in affective commitment were immediate. Moreover, teams of leaders who had been consistently directive showed higher affective commitment as compared to teams of leaders who had a history of being empowering but later shifted to being directive. First time managers can get inputs on how they should enact their leadership style and be aware that switching between styles may impose long-term costs on the team’s affective commitment and satisfaction with the leader.


2016 ◽  
Vol 10 (10) ◽  
pp. 133
Author(s):  
Mohammad Ali Nasiri Khalili ◽  
Mostafa Kafaei Razavi ◽  
Morteza Kafaee Razavi

Items supplies planning of a logistic system is one of the major issue in operations research. In this article the aim is to determine how much of each item per month from each supplier logistics system requirements must be provided. To do this, a novel multi objective mixed integer programming mathematical model is offered for the first time. Since in logistics system, delivery on time is very important, the first objective is minimization of time in delivery on time costs (including lack and maintenance costs) and the cost of purchasing logistics system. The second objective function is minimization of the transportation supplier costs. Solving the mathematical model shows how to use the Multiple Objective Decision Making (MODM) can provide the ensuring policy and transportation logistics needed items. This model is solved with CPLEX and computational results show the effectiveness of the proposed model.


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