A sizing-based approach to evaluate hypersonic demonstrators: demonstrator-carrier constraints

2020 ◽  
Vol 124 (1279) ◽  
pp. 1318-1349 ◽  
Author(s):  
J.G. Haley ◽  
T.P. McCall ◽  
I.W. Maynard ◽  
B. Chudoba
Keyword(s):  
Solution Space ◽  
Growth Potential ◽  
Design Matrix ◽  
Study Results ◽  
Research Aircraft ◽  
Time Requirements ◽  
Payload Mass ◽  
Near Term ◽  
Flight Hardware ◽  
Carrier Vehicle

ABSTRACTThe objective of this study is to identify, evaluate, and provide recommendations towards the realisation of near-term hypersonic flight hardware through the consideration of carrier vehicle constraints. The current rush of available funds for hypersonic research cannot cause a program to ignore growth potential for future missions. The prior NB-52 carrier vehicles, famous for the X-15 and X-43A missions, are retired. Next generation hypersonic demonstrator requirements will necessitate a substitution of carrier vehicle capability. Flight vehicle configuration, technology requirements, and recommendations are arrived at by constructing and evaluating a hypersonic technology demonstrator design matrix. This multi-disciplinary parametric sizing investigation of hypersonic vehicle demonstrators focuses on the evaluation of the combined carrier platform, booster, and hypersonic cruiser solution space topography. Promising baseline configurations are evaluated against operational requirements by trading fuel type, endurance cruise time, and payload weight. The multi-disciplinary study results are constrained with carrier payload mass and geometry limitations. The multi-disciplinary results provide physical insights into near-term hypersonic demonstrator payload and cruise time requirements that will stretch the capability of existing carrier aircraft. Any growth in hypersonic research aircraft size or capability will require new carrier vehicle investments.

Technology and operational sensitivity assessment for hypersonic endurance flight vehicles

2015 ◽  
Vol 119 (1213) ◽  
pp. 365-387 ◽  
Author(s):  
B. Chudoba ◽  
G. Coleman ◽  
A. Oza ◽  
L. Gonzalez ◽  
P.A. Czysz
Keyword(s):  
Solution Space ◽  
Screening Process ◽  
Flight Vehicles ◽  
Sensitivity Assessment ◽  
Operational Solution ◽  
Technical Risk ◽  
Research Aircraft ◽  
Speed Regime ◽  
Minute Duration ◽  
Breathing Endurance

AbstractIn an effort to increase the air-breathing endurance capability of current hypersonic research aircraft (i.e. X-43, 7 seconds; X-51, 5 minutes), the authors have explored the technical and operational solution space for a 30 minute cruise endurance demonstrator operating in the Mach 6 to Mach 8 speed regime. The focus of this activity has been on exploration of the available solution space through a unique screening process to assess the implication and interplay between the (a) mission, (b) baseline vehicle, and (c) operational scenarios. This study concludes that an air-launched, liquid hydrogen fuelled, 30 minute duration Mach 6 demonstrator (with 10 min Mach 8 capability) provides the largest feasible solution space of the trades examined (i.e. largest design margins, lowest technical risk) when compared to a kerosene-powered equivalent.

scholarly journals Afghanistan: Balancing Social and Security Spending in the Context of a Shrinking Resource Envelope

2014 ◽  
Vol 31 (2) ◽  
pp. 165-197 ◽  
Author(s):  
Aqib Aslam ◽  
Enrico Berkes ◽  
Martin Fukac ◽  
Jeta Menkulasi ◽  
Axel Schimmelpfennig
Keyword(s):  
Central Government ◽  
Fiscal Sustainability ◽  
Growth Potential ◽  
Medium Term ◽  
Public Finances ◽  
Donor Support ◽  
Macroeconomic Impact ◽  
Strategic Policy ◽  
Near Term ◽  
The Government

For Afghanistan, the dual prospect of declining donor support and high ongoing security spending over the medium term keeps its government budget tight. This paper uses a general equilibrium model to capture the security–development trade-off facing the government in its effort to rehabilitate growth and fiscal sustainability. In particular, it considers strategic policy options for counteracting and minimizing the negative macroeconomic impact of possible aid and revenue shortfalls. We find that the mobilization of domestic revenues through changes in tax policy is the preferred policy response for the Afghan central government. Such a response helps to place its finances on a sustainable path in the near term and preserve most of the growth potential. Cutting expenditures balances public finances but causes the economy to permanently shrink. Debt financing helps to preserve much of the economy size but can quickly put the sustainability of public finances at risk.

scholarly journals The Value Of Growth At A Reasonable Price: Evidence From The Taiwan Stock Exchange

2012 ◽  
Vol 11 (9) ◽  
pp. 1041
Author(s):  
Kathleen Hodnett ◽  
Heng-Hsing Hsieh
Keyword(s):  
Stock Prices ◽  
Stock Exchange ◽  
Growth Potential ◽  
Stock Selection ◽  
Selection Technique ◽  
Examination Period ◽  
Taiwan Stock Exchange ◽  
Study Results ◽  
Investment Styles ◽  
Reasonable Price

Value and growth represent two opposite investment styles when price multiples such as the price-to-earnings ratio and the price-to-market ratio are used to classify the investment styles of equities. Motivated by the argument of Peters (1991) and Broussard, Michayluk and Needy (2005) that price multiples are imperfect valuation measures for firms other than firms in mature industries, and also the argument of Ahmed and Nanda (2001) that value and growth investing strategies should not be mutually exclusive, this study attempts to identify stocks with above-average sales growth that trade at average or below-average price-to-sales multiples. Their performance relative to pure growth portfolios is subsequently analyzed. Using variants of historical growth rates relative to previous month, previous year, historical low and historical high as measures of growth potential, and the price-to-sales multiple as the measure of the reasonableness of the stock prices, we construct growth-at-a-reasonable-price (GARP) portfolios on the Taiwan Stock Exchange over the period from 01 January 2000 through 31 March 2010. Study results indicate that the GARP portfolios outperform their counterpart pure growth portfolios over the examination period. The incremental contributions of GARP measured in terms of the return improvements, risk reduction and improvements in the Sharpe ratios when switching from the pure growth stock selection technique to the GARP selection technique, is found to be significant over the examination period.

The Digital Economy Readiness Study

2021 ◽  
pp. 32-51
Author(s):  
Radek Liska
Keyword(s):  
Czech Republic ◽  
Digital Economy ◽  
Global Market ◽  
Growth Potential ◽  
Competitive Advantages ◽  
The Czech Republic ◽  
Research Areas ◽  
Study Results ◽  
Market Situation ◽  
Positive Outlook

The Czech Republic has experienced tremendous growth over the last three decades. However, as the previously exploited competitive advantages (e.g., low labour cost) lose growth potential, the country has to address the digital economy sector. The digital economy readiness study analyses and merges findings from the European and OECD databases, outlining the current situation in the country. Also, the study compares the skill set supplied by the Czech workforce with the global market situation. Research areas cover analysis of diverse factors such as age, education, gender, and nationality. Study results show that the Czech Republic has a substantial competitive advantage both within the EU and across OECD thanks to its highly skilled workforce. Hence, ongoing digital transformation gives a positive outlook for further development of the Czech digital economy.

scholarly journals Features of Time Perspective of Gifted Adolescents and their Peers

2017 ◽  
Vol 9 (1) ◽  
pp. 106-114 ◽  
Author(s):  
M.D. Kondratyev
Keyword(s):  
Time Perspective ◽  
Peer Group ◽  
Statistical Processing ◽  
Temporal Orientation ◽  
Study Results ◽  
The Future ◽  
Near Term ◽  
Study Participants ◽  
Gifted Adolescents

The article presents data from a study of features of time perspective of gifted adolescents and their coevals. The study involved 274 adolescent. To study the features of the time perspective of personality were chosen questionnaire time perspective Zimbardo (ZTPI), as well as processed according to the method of motivational induction J.Nuttin questionnaires with incomplete sentences and writings of the study participants. During the statistical processing of the data, it was found that gifted adolescents characterized by the following features: relatively high scores by type of temporal orientation "negative past" and "future". For a time the future prospects are characterized by: a relatively high frequency of references to objects motivational groups "Work", "Knowledge" (near-term); "Development", "Work" (long term). The length of the prospects for the future in a group of gifted adolescents is higher than the peer group. The study results will be useful for psychologists practitioners in working with adolescents.

scholarly journals Neonatal hyperbilirubinaemia and its early outcome

1970 ◽  
Vol 31 (3) ◽  
pp. 17-20
Author(s):  
D. Nepal ◽  
D. Banstola ◽  
A. K. Dhakal ◽  
U. Mishra ◽  
C. Mahaseth
Keyword(s):  
Tertiary Care ◽  
Institute Of Medicine ◽  
Clinical Sepsis ◽  
Early Outcome ◽  
Paediatric Hospital ◽  
Study Results ◽  
Common Causes ◽  
Study Population ◽  
Near Term ◽  
Key Words Hyperbilirubinaemia

Introduction: Jaundice is an important cause of morbidity in the neonatal period, especially in the 1st week of life. our Objective of the study was to find out early outcome of babies admitted in Kanti Children Hospital with neonatal jaundice (NNJ) and its association with other co-morbidities. Methods: This is a retrospective study conducted in tertiary care paediatric hospital from 1st March to1st June 2009. Altogether 73 babies were included in the study. Results: Male babies outnumbered females (72.6% vs. 27.4%). Only 2.4% babies were near-term. Low birth weight (LBW) babies constituted 19.2% of the study population. Clinical sepsis as defined by WHO criteria was observed in 86.3% of babies. Nearly 50% of the babies had serum bilirubin of 15-19.9 mg/dl. Most of the babies (94.5%) improved with 5.5% of mortality. Conclusions: Hyperbilirubinaemia is one of the most common causes of hospital admission in our nursery and it is associated with various other clinical morbidities. Phototherapy is effective in most of the time, but exchange transfusion should also be carried out when phototherapy fails. Causes of hyperbilirubinaemia should be searched extensively especially to rule out haemolysis Key words: Hyperbilirubinaemia, kernicterus, neonates, phototherapy DOI: 10.3126/joim.v31i3.2990 Journal of Institute of Medicine, December, 2009; 31(3) 17-20

scholarly journals Financial analysis of potential Pinus patula plantations in Antioquia, Colombia

2020 ◽  
Vol 73 (2) ◽  
pp. 9227-9242 ◽  
Author(s):  
Laura Ramírez ◽  
Sergio A. Orrego ◽  
Héctor I. Restrepo
Keyword(s):  
Financial Analysis ◽  
Rotation Period ◽  
Growth Potential ◽  
Similar Proportion ◽  
Pinus Patula ◽  
Annual Increment ◽  
Yield Data ◽  
Volume Yield ◽  
Study Results ◽  
Stumpage Price

The establishment of commercial forest plantations requires the selection of sites where reasonable profitability can be attained. A financial analysis was made for the identification of the most suitable areas for the establishment of new Pinus patula plantations in the central region of Antioquia, Colombia. The analysis was performed assuming basic silvicultural treatments at the establishment but no management during the entire rotation period. A volume yield data at the stand level was obtained from a previously fitted model that uses biophysical variables and stand density as predictors. The estimated stand volume, a detailed cash flow, and a derived stumpage price were combined to perform a financial analysis. The Land Expectation Value (LEV) and Internal Rate of Return (IRR) at the optimal rotation age, along with their spatial variation, were calculated in this study. Results suggest that the estimated volume and the current stumpage price are not sufficient to guarantee reasonable profitability for new timberland investments. While the LEV was negative, the IRR was in the range 4.1±1.5%, which is less than the discount rate of 6.8% used in the financial analysis. However, a positive LEV and an IRR at 8% would be achieved if forest productivity increases by 20% because of silvicultural practices or costs reduction in a similar proportion (obtaining IRRs up to 8.4%). Moreover, if the government provide subsidies, the IRR would increase up to 10.3% (without requiring an increase in productivity or a decrease in costs) on sites with high growth potential (mean annual increment greater than 16 m3 ha-1 year-1), and close to the mills (less than 45 km radii).

scholarly journals Changes over time in genetic parameters for growth in bulls and assessment of suitability of test methods

2014 ◽  
Vol 59 (No. 1) ◽  
pp. 19-25 ◽  
Author(s):  
A. Svitáková ◽  
J. Bauer ◽  
J. Přibyl ◽  
Z. Veselá ◽  
L. Vostrý
Keyword(s):  
Fixed Effects ◽  
Genetic Parameters ◽  
Additive Genetic Variance ◽  
Performance Testing ◽  
Growth Potential ◽  
Parameter Estimates ◽  
Progeny Testing ◽  
Study Results ◽  
Residual Variances ◽  
Over Time

Objectives of the study were to examine alternative measures of growth potential of bulls in testing stations, determine whether genetic parameter estimates of such traits changed over time, and examine whether existing methods for performance testing were appropriate. Records from 1980 to 2010 of 44 425 Fleckvieh bulls in Czech progeny testing stations were analyzed. The following traits were examined: weight at the beginning of the test (150<sup>th</sup> day of age), weight at the end of the test (530<sup>th</sup> day of age), gain from birth to the beginning of the test, and gain during the test. Fixed effects in five multi-trait animal models were station-year-season groups, linear and quadratic regressions on age, and regression on heterozygosity (proportion of an individual&rsquo;s loci with alleles from different ancestor breeds). Random effects included additive genetic, permanent environment, and residual variances. Separate analyses were conducted in four consecutive time periods (1980&ndash;1987, 1988&ndash;1992, 1993&ndash;1997, and 1998&ndash;2010). Across these time intervals, estimates of additive genetic variance decreased for all of the traits, while estimates of residual variances increased. In consequence, heritability estimates for all of the traits decreased over time. This decrease was most apparent for gain during the test, for which heritability declined by more than 50% over the course of the study. Results demonstrate that over three decades, the system of testing came into conflict with genetic improvement of the breed, possibly because the measured traits changed genetically over the course of selection. Regular analysis of the recorded data, re-estimation of genetic parameters in relation to time, and appropriate modification of existing methods of rearing/fattening in station tests are required. When such inspections are neglected, data from the testing stations may not accurately reflect genetic merit of individual animals.

An approach for making optimal decisions in building energy efficiency retrofit projects

2016 ◽  
Vol 27 (3) ◽  
pp. 348-368 ◽  
Author(s):  
Aslihan Senel Solmaz ◽  
Fahriye H Halicioglu ◽  
Suat Gunhan
Keyword(s):  
Energy Efficiency ◽  
Solution Space ◽  
Building Energy ◽  
Multiple Criteria ◽  
Optimization Approach ◽  
Building Energy Efficiency ◽  
Main Challenge ◽  
Study Results ◽  
Wide Range ◽  
Project Objectives

The study presents an optimization-based decision support approach to determine the optimal energy efficiency retrofit options in existing buildings. The main challenge encountered in the decision-making process of building retrofit projects is the selection of an optimal set of solutions within a wide range of solution space according to multiple criteria. In order to overcome this problem, this study uses an integrated optimization approach by combining both the variance-based sensitivity analysis and optimization methods to maximize energy savings and optimize financial returns in building energy efficiency retrofit projects. The proposed approach was applied to an existing public school building in Izmir, Turkey that represents hot-humid climate to test its validity and performance. The optimizations were performed and results were obtained for three different scenarios whose content was determined based on project objectives and constraints fulfilled by a survey conducted by building users. The case study results indicate that the proposed approach is effective in defining the application order of retrofit options by identifying the most influential parameters for building energy efficiency and finding out the optimal retrofit solutions per multiple criteria.

scholarly journals Potential development directions of methods for assessing and evaluating the efficient performance of construction organizations

2020 ◽  
Vol 17 (6) ◽  
pp. 238-245
Author(s):  
N. V. Chepachenko ◽  
◽  
M. N. Yudenko ◽  
S. A. Nikolikhina ◽  
N. A. Polovnikova ◽  
...  
Keyword(s):  
Economic Efficiency ◽  
Production Management ◽  
Methodological Approach ◽  
Golden Rule ◽  
Growth Potential ◽  
Index Method ◽  
Construction Organizations ◽  
Efficient Performance ◽  
Study Results ◽  
Integrated Cost

The article presents the study results of potential directions for the development of methods for assessing and evaluating the efficient performance of construction organizations that increase the objectivity of assessing and evaluating the results of activities in the field of production and sale of construction products (works, services) and the quality of management decisions. The authors propose systematization of the applied and recommended methods of assessing and evaluating the economic efficiency of construction organizations. Herewith, several methods are considered, namely: the integrated cost method based on a comprehensive accounting of the totality of production, management, commercial and transaction costs; the integrated resource method that implements the concept of accounting for the applied totality of labor, material, technical and financial resources; the resource-integral method based on the symbiosis of resource and cost methods; the optimization method reflecting the concept of a criterion approach; the polystructural method, reflecting the concept of measuring and assessing economic efficiency based on the assessment of the growth potential of construction organizations, due to the influence of factors of intensification of production; the index method based on the concept of following the «golden rule of enterprise economics». A potential methodological approach to assessing alternative types of efficiency (socio-economic, socio-ecological, ecological-economic, ecological-socio-economic ones) in the Descartes spatial coordinate system is proposed.

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