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Tytuł:
Analysis of SQL Injection Detection Techniques
Autorzy:
Singh, J. P.
Powiązania:
https://bibliotekanauki.pl/articles/375681.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
SQL Injection
runtime monitoring
Static Analysis
Opis:
SQL Injection is one of the vulnerabilities in OWASP's Top Ten List forWeb Based Application Exploitation. These type of attacks take place on Dynamic Web applications as they interact with databases for various operations. Current Content Management System like Drupal, Joomla or Wordpress have all information stored in their databases. A single intrusion into these type of websites can lead to overall control of websites by an attacker. Researchers are aware of basic SQL Injection attacks, but there are numerous SQL Injection attacks which are yet to be prevented and detected. Over here, we present the extensive review for the Advanced SQL Injection attack such as Fast Flux SQL Injection, Compounded SQL Injection and Deep Blind SQL Injection. We also analyze the detection and prevention using the classical methods as well as modern approaches. We will be discussing the Comparative Evaluation for prevention of SQL Injection.
Źródło:
Theoretical and Applied Informatics; 2016, 28, 1-2; 37-55
1896-5334
Pojawia się w:
Theoretical and Applied Informatics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimal design of RC frames using a modified hybrid PSOGSA algorithm
Optymalny projekt ramy RC z wykorzystaniem zmodyfikowanego algorytmu hybrydowego PSOGSA
Autorzy:
Chutani, S.
Singh, J.
Powiązania:
https://bibliotekanauki.pl/articles/230376.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
projekt optymalny
konstrukcja żelbetowa
optymalizacja demokratyczna roju cząstek
samoadaptacyjny algorytm
grawitacyjnego wyszukiwania
projektowanie
Indie
norma indyjska
optimum design
reinforced concrete structure
democratic particle swarm optimization
selfadaptive gravitational search algorithm
design
Indian standard
Opis:
The present study has been taken up to emphasize the role of the hybridization process for optimizing a given reinforced concrete (RC) frame. Although various primary techniques have been hybrid in the past with varying degree of success, the effect of hybridization of enhanced versions of standard optimization techniques has found little attention. The focus of the current study is to see if it is possible to maintain and carry the positive effects of enhanced versions of two different techniques while using their hybrid algorithms. For this purpose, enhanced versions of standard particle swarm optimization (PSO) and a standard gravitational search algorithm (GSA), were considered for optimizing an RC frame. The enhanced version of PSO involves its democratization by considering all good and bad experiences of the particles, whereas the enhanced version of the GSA is made self-adaptive by considering a specific range for certain parameters, like the gravitational constant and a set of agents with the best fitness values. The optimization process, being iterative in nature, has been coded in C++. The analysis and design procedure is based on the specifications of Indian codes. Two distinct advantages of enhanced versions of standard PSO and GSA, namely, better capability to escape from local optima and a faster convergence rate, have been tested for the hybrid algorithm. The entire formulation for optimal cost design of a frame includes the cost of beams and columns. The variables of each element of structural frame have been considered as continuous and rounded off appropriately to consider practical limitations. An example has also been considered to emphasize the validity of this optimum design procedure.
W niniejszym artykule przedstawiono bardziej realistyczny i optymalny projekt żlbetowych ram konstrukcyjnych (RC) poprzez hybrydyzację ulepszonych wersji standardowej optymalizacji roju cząsteczek (PSO) oraz standardowy algorytm wyszukiwania grawitacyjnego (GSA). Podejście proponowane w niniejszej pracy koncentruje się na hybrydyzacji ulepszonych wersji standardowej optymalizacji roju cząsteczek (PSO) oraz standardowym algorytmie wyszukiwania grawitacyjnego (GSA). PSO została zdemokratyzowana poprzez uwzględnienie wszystkich dobrych i złych doświadczeń w zakresie cząsteczek, podczas gdy GSA został zmieniony na samodostosowujący, uwzględniając określony zakres dla niektórych parametrów, takich jak np. stała grawitacyjna i zestaw czynników o najlepszych wartościach sprawności. Optymalny rozmiar i wzmocnienie elementów zostały określone dzięki zastosowaniu techniki w środowisku komputerowym, w którym cały proces analizy, projektowania i optymalizacji został zakodowany w C++. Procedura analizy i projektowania przebiega zgodnie ze specyfikacjami kodów indyjskich. Okazało się, że zastosowanie samodostosowującego algorytmu wyszukiwania grawitacyjnego wraz z demokratyczną techniką optymalizacji roju cząsteczek zapewnia dwie wyraźne przewagi nad standardową PSO i GSA, a mianowicie lepszą zdolność do ucieczki od lokalnej optymalności i szybszy współczynnik konwergencji. Całe sformułowanie dla optymalnego projektu kosztów ramy obejmuje zarówno koszt belek i słupów. W tym podejściu, zmienne każdego elementu ramy konstrukcyjnej zostały uznane za funkcje ciągłe i zaokrąglone odpowiednio do zastosowania praktycznego znaczenia niniejszego badania. Rozważono kilka przykładów, które podkreślają ważność optymalnej procedury projektowania, a wyniki porównano z wcześniejszymi badaniami, w celu sprawdzenia ich skuteczności i efektywności. Proponowany algorytm pokonuje ograniczenia dwóch indywidualnych algorytmów, biorąc pod uwagę ich hybrydę, a tym samym poprawia ogólną wydajność. Wprowadzono niezbędne zmiany, aby badanie było zgodne z wcześniejszymi badaniami. Porównanie z innymi wcześniej stosowanymi technikami hybrydowymi pokazuje, że czas potrzebny na przeprowadzenie procesu optymalizacji w niniejszym badaniu – z wykorzystaniem techniki MPSOGSA – został znacznie zmniejszony. Ponadto, podczas projektowania ram RC obniżono całkowity koszt za pomocą techniki MPSOGSA. Obniżenie kosztów w obszarze stali odgrywa większą rolę w optymalizacji, w porównaniu do redukcji kosztów w przekroju poprzecznym elementów ramy, co zostało szczegółowo przeanalizowane na przykładzie.
Źródło:
Archives of Civil Engineering; 2017, 63, 4; 123-134
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Map construction and localization using Lego Mindstorms NXT
Autorzy:
Singh, J.
Bedi, P.
Powiązania:
https://bibliotekanauki.pl/articles/385248.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
LEGO Mindstorms NXT
TriBot
ultrasonic sensor
map construction
localization
particle filter
MATLAB
mobile robot
RWTH – Mindstorms NXT
toolbox
Opis:
Maps are very useful for understanding unknown places before visiting them as maps represent spatial relationships between various objects in a region. Using robots for map construction is an important field these days as robots can reach places which may be inaccessible to human beings. This paper presents a method to use the data obtained from a single ultrasonic sensor mounted on a robot, to construct a map and localize the robot within that map. Map of the previously unknown environment is created with the help of a mobile robot, built using Lego Mindstorms NXT assembled in a modified TriBot configuration. The robot is equipped with an ultrasonic sensor and is controlled from a computer system running a MATLAB program, which communicates with the NXT over a USB or Bluetooth connection and performs complex calculations that are not possible for the NXT itself. After the map construction, the robot finds its position in the map by using a particle filter. Implementation has been done in MATLAB programming environment using RWTH – Mindstorms NXT Toolbox and has been successfully tested for map construction of a room and localization within that room with the use of a TriBot.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2013, 7, 3; 22-30
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Two-dimensional deformation in a thermoelastic solid with microtemperatures subjected to an internal heat source
Autorzy:
Ailawalia, P.
Budhiraja, S.
Singh, J.
Powiązania:
https://bibliotekanauki.pl/articles/265902.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
termoelastyczność
źródło ciepła
mikrotemperatura
thermoelasticity
internal heat source
normal mode
microtemperatures
Opis:
The purpose of this paper is to study the two dimensional deformation in a generalized thermoelastic medium with microtemperatures having an internal heat source subjected to a mechanical force. The force is acting along the interface of generalized thermoelastic half space and generalized thermoelastic half space with microtemperatures having an internal heat source. The normal mode analysis has been applied to obtain the exact expressions for the considered variables. The effect of internal heat source and microtemperatures on the above components has been depicted graphically.
Źródło:
International Journal of Applied Mechanics and Engineering; 2018, 23, 1; 5-21
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On Rayleigh wave in generalized magneto-thermoelastic media with hydrostatic initial stress
Autorzy:
Singh, B.
Kumari, S.
Singh, J.
Powiązania:
https://bibliotekanauki.pl/articles/201293.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
generalized thermoelasticity
hydrostatic initial stress
magnetic field
Rayleigh wave
frequency equation
Opis:
The governing equations of generalized magneto-thermoelasticity with hydrostatic initial stress are solved for surface wave solutions. The particular solutions in the half-space are applied to the boundary conditions at the free surface of the half-space to obtain the frequency equation of Rayleigh wave. The frequency equation is approximated for small thermal coupling and small reduced frequency. The velocity of propagation and amplitude-attenuation factor of Rayleigh wave are computed numerically for a particular material. Effects of magnetic field and hydrostatic initial stress on the velocity of the propagation and amplitude-attenuation factor are shown graphically.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 2; 349-352
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analytical solution of a fractional model of fluid flow through narrowing system in terms of Mittag-Leffler function
Autorzy:
Choudhary, A.
Kumar, D.
Singh, J.
Powiązania:
https://bibliotekanauki.pl/articles/264897.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
transformata Hankela
funkcja Bessela
pochodna Caputo
narrowing system
generalized Caputo fractional derivative
Sumudu transform
finite Hankel transform
Bessel function
Mittag-Leffler function
Opis:
In this work, we discuss a fractional model of a flow equation in a simple pipeline. Pipeline narrowing is a crucial aspect in drinking water distribution processes, sewage system and in oil-well schemes. The solution of the mathematical model is determined with the aid of the Sumudu transform and finite Hankel transform. The results derived in the current study are in compact and graceful forms in terms of the Mittag-Leffler type function, which are convenient for numerical and theoretical evaluation.
Źródło:
International Journal of Applied Mechanics and Engineering; 2020, 25, 1; 1-11
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of data aggregation methods and related issues in Wireless Sensor Networks
Autorzy:
Nels, S. Ninisha
Singh, J. Amar Pratap
Powiązania:
https://bibliotekanauki.pl/articles/2050167.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
data aggregation
wireless sensor network
WSN
clustering
cluster head
CH
cluster-based data aggregation
Opis:
Data aggregation is the process aimed at reducing the transmission count of packets being transmitted in the framework of in-network data processing. It is the data transmission model that takes the information transmitted from different nodes and generates a single data packet after finding and eliminating the redundant packets. Accordingly, this process decreases the transmission count and makes it possible to consume less energy. The major issues in data aggregation mechanism are related to reduction of latency and to energy balancing. Moreover, it is very complex to resolve the issue of packet loss, which is the failure of one or more transmitted packets to arrive at their destination due to the bad and/or congested channel conditions. The present survey involves a collection of 50 research papers dealing with the data aggregation models in wireless sensor networks (WSN). Various data aggregation methods, like the cluster-based approach, structure-free method, tree-based approach, in-network methods, and energy based aggregation model are considered in this survey, regarding the application and the energy usage involved. On the basis of the survey, the issues and drawbacks faced by the respective methodologies are highlighted. In addition, the paper presents simple statistics of the studies considered with respect to the performance measures, simulation tools, publication year, and classification of methods. The future dimensions of the respective research are supposed to be based on the challenges identified in this survey.
Źródło:
Control and Cybernetics; 2020, 49, 4; 419-446
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comprehensive review of renewable energy production from biomass-derived bio-oil
Autorzy:
Sharma, M.
Singh, J.
Baskar, C.
Kumar, A.
Powiązania:
https://bibliotekanauki.pl/articles/80718.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
renewable energy
biomass
bio-oil
bioenergy
biomass source
fast pyrolysis
hydrothermal liquefaction
climate change
energy security
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2019, 100, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Management of sugar industrial wastes through vermitechnology
Autorzy:
Bhat, S.A.
Singh, J.
Vig, A.P.
Powiązania:
https://bibliotekanauki.pl/articles/11795.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Opis:
The present paper discusses the role of earthworms in recycling of sugar industrial wastes. The wastes generated from sugar industry are pressmud, bagasse, bagasse fly ash, sugar cane trash, sugar beet mud, sugar beet pulp, molasses etc. These wastes when mixed with other organic substrates become ideal mixtures for growth of earthworms. These wastes if stored in open field’s causes contamination in the environment and may cause several diseases in public health. But the governments have been unable to tackle the menace of solid waste pollution due to dearth of appropriate technologies, finance and space. Therefore, environment friendly and cost effective technologies for nutrient recycling or remediation of wastes are being advocated as an alternative means for conserving and replenishing natural resources of the ecosystems. Vermicomposting is one such technology that synergises microbial degradation with earthworm’s activity for reducing, reusing and recycling waste materials in a shorter span of time. Earthworm technology can convert sugar industrial wastes into valuable fertilizing material. The final product (vermicompost) produced during the process of vermicomposting is nutrient rich organic fertilizer with plant available nutrients such as nitrogen, potassium, calcium and phosphorus. In the present study an attempt has been made to document the role of earthworms in reuse of sugar industry waste.
Źródło:
International Letters of Natural Sciences; 2016, 55
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cumulative Sum Control Charts for Truncated Normal Distribution under Measurement Error
Autorzy:
Sankle, R.
Singh, J. R.
Mangal, I. K.
Powiązania:
https://bibliotekanauki.pl/articles/465820.pdf
Data publikacji:
2012
Wydawca:
Główny Urząd Statystyczny
Tematy:
Truncated Normal Distribution Measurement Error
ARL and CSCC
Opis:
In the present paper Cumulative Sum Control Chart (CSCC) for the truncated normal distribution under measurement error (r) is discussed. The sensitivity of the parameters of the V-Mask and the Average Run Length (ARL) is studied through numerical evaluation for different values of r.
Źródło:
Statistics in Transition new series; 2012, 13, 1; 95-106
1234-7655
Pojawia się w:
Statistics in Transition new series
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First report of the earthworm Pontoscolex corethrurus (Müller, 1857) from Punjab, India
Autorzy:
Singh, S.
Singh, J.
Sharma, A.
Pal Vig, A.
Shakoor, A.
Powiązania:
https://bibliotekanauki.pl/articles/11913.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Źródło:
International Letters of Natural Sciences; 2018, 68
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Applications of Some Well-Known Skewed Distributions to Greenhouse Gas Emissions Data
Autorzy:
Shakil, M.
Singh, J. N.
Kibria, B. M. G.
Khadim, A.
Ahsanullah, M.
Powiązania:
https://bibliotekanauki.pl/articles/1839385.pdf
Data publikacji:
2021
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Goodness of fit test
Greenhouse gas emissions
Probability distributions
Statistical analysis
Opis:
In many problems of transportation and environmental processes and designs, fitting of a continuous probability distribution to the greenhouse gas emissions data from cars may be helpful in predicting the probability or forecasting the frequency of occurrence of the greenhouse gas emissions from burning fossil fuel for our cars, trucks, ships, trains, and planes, and planning beforehand. The objective of this paper is to study and conduct a statistical analysis of the greenhouse gas emissions data from cars. Since our data are skewed in nature, we fit the following well known skewed distributions: 3 parameter Birnbaum-Saunders (or fatigue-life), gamma, 3 parameter gamma, generalized extreme value, 3 parameter lognormal, 4 parameter Pearson 6 and Weibull distributions. We have tested the goodness of fit these distributions to a random sample of the greenhouse gas emissions data from 32 different models of cars to determine their applicability and best fit to these data based on the Kolmogorov-Smirnov, Anderson-Darling, and Chi-Squared Goodness-of-Fit Tests.
Źródło:
World Scientific News; 2021, 162; 1-15
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Intranasal (IN) COVID-19 vaccines - a breakthrough
Autorzy:
Gambhir, R.S.
Kaur, K.
Matariya, R.
Singh, B.
Sood, R.
Singh, J.
Powiązania:
https://bibliotekanauki.pl/articles/28765534.pdf
Data publikacji:
2023
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Opis:
Emerging variants of COVID-19 have threatened the effectiveness of intramuscular (IM) vaccines since that are made to target only the spike protein. Development of Intranasal (IN) vaccination has been proven to provide both the mucosal and systemic immune responses for broader and long lasting protection. Many IN vaccine candidates (virus-vectored vaccines, recombinant subunit vaccines and live attenuated vaccines) are in different phases of clinical trials and in near future many companies would be releasing their vaccines into the drug market. Potential advantages of IN vaccination over IM vaccination makes them ideal to be administered in children and developing populations of the world. This paper focuses on the very recent developments in intranasal vaccination with a spotlight on their safety and efficacy concerns. IN vaccination can prove to be game-changer in handling COVID-19 and potential viral contagious diseases in future.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2023, 74, 1; 15-18
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Static analysis of functionally graded plate using nonlinear classical plate theory with von-Karman strains
Autorzy:
Singh, S. J.
Harsha, S. P.
Powiązania:
https://bibliotekanauki.pl/articles/265766.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
metoda Naviera
teoria płyt
odkształcenie
functionally graded materials (FGM) plate
Von-Karman strain
nonlinear classical plate theory (NLCPT)
Navier’s method
Opis:
The present study is based on the nonlinear bending analysis of an FGM plate with Von-Karman strain based on the non-linear classical plate theory (NLCPT) with in-plane displacement and moderate rotation. Non-linear bending analysis based on stresses and transverse deflections is then carried out for the plate for the complex solution obtained using an analytical method viz. Navier’s method. The equations of motion and boundary conditions are obtained using the Principle of Minimum Potential Energy (PMPE) method and material property is graded in thickness direction according to simple power-law distribution in terms of volume fractions of the constituents. The effect of the span-to-thickness ratio and FGM exponent on the maximum central deflection and stresses are studied. The results show that the response is transitional with respect to ceramic and metal and the complex solution predicts the real behavior of stresses and deflections in the functionally graded plate. The functionally graded plate is found to be more effective for moderately thick and thick plates, which is inferred by a complex nature of the solution. For FGM plates, the transverse deflection is in-between to that of metal and ceramic rich plates. The complex nature of the solution also gives information about the stress distribution in the thickness direction.
Źródło:
International Journal of Applied Mechanics and Engineering; 2018, 23, 3; 707-726
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assay of the Insensitive High Explosive 3-Nitro-1,2,4-triazol-5-one (NTO) by Acid-Base Titration
Autorzy:
Nandi, A. K.
Singh, S. K.
Kunjir, G. M.
Singh, J.
Mandal, A. K.
Pandey, R. K.
Powiązania:
https://bibliotekanauki.pl/articles/358351.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
NTO
purity
acid-base titration
HPLC
quality control
Opis:
The insensitive high explosive 3-nitro-1,2,4-triazol-5-one (NTO) is a weak acid (pKa 3.76) due to the labile N–H bond. The weakly acidic character of this compound is exploited for its assay by aqueous acid-base titration. The NTO sample was dissolved in water and the resultant solution was titrated against 0.07 N NaOH solution using phenolphthalein as indicator. Regular batch samples were assayed by this method and the results were compared with those obtained by the HPLC method. The aqueous acid-base titration method was found to be suitable for the quality control of the product.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 1; 113-122
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of Ammonium Sulfamate Nitration for the Preparation of Ammonium Dinitramide
Autorzy:
Mandal, A. K.
Kunjir, G. M.
Singh, J.
Adhav, S. S.
Singh, S. K.
Pandey, R. K.
Bhattacharya, B.
Lakshmi Kantam, M.
Powiązania:
https://bibliotekanauki.pl/articles/358022.pdf
Data publikacji:
2014
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Opis:
The reaction kinetics for the preparation of ammonium dinitramide (ADN) is described. ADN is the ammonium salt of the dinitramide anion, and belongs to the group of inorganic oxidizers, mainly useful for energetic rocket propellant formulations, particularly for underwater applications. It is also a potential candidate to replace ammonium perchlorate (AP), in order to develop chlorine-free, green propellants. At HEMRL, ADN is prepared by the nitration of ammonium sulfamate (AS) using mixed acid, followed by hydrolysis, neutralization with ammonia (g) and rectification using solvent. The nitration of ammonium sulfamate (AS) is carried out at a subzero temperature of -40 ±1 °C. The yield of ADN is reliant on the formation of dinitramidic acid, an intermediate product formed during the hydrolysis step, and its stability is predominantly dependent upon the level of acidity and temperature of the reaction medium. Prior to these kinetics studies, process optimization of the nitration of ammonium sulfamate (AS) was performed and gave the final mole ratio of AS:HNO3:H2SO4. Since the nitration of AS is sensitive to temperature, the rate of reaction was studied at fixed temperatures with variation of time, keeping all of the other parameters, such as vessel volume, agitator speed, feed rate etc., constant. During these studies, predetermined quantities of ammonium sulfamate (AS) and mixed acid were allowed to react at a fixed temperature (-40 ±1 °C) for different reaction periods to generate the concentration profile of AS. Using this concentration profile, the reaction order and reaction rate constant were evaluated. In order to find the effect of temperature on the reaction rate and yield, experiments were conducted at other temperatures such as -30 and -50 °C. In the present studies, it was found that the optimum temperature of nitration is -40 ±1 °C and that the rate of reaction follows a pseudo second order process with rate constant 0.01113 (min-1)•(mol/L)-1. The reaction time evaluated for 55 to 60% conversion is about 70-80 minutes at -40 ±1 °C, based on this kinetics. The activation energy of AS nitration was found to be -4.6 kcal/mol, using the reaction kinetic data based on the temperature dependent rate equation derived from Arrhenius’s law.
Źródło:
Central European Journal of Energetic Materials; 2014, 11, 1; 83-97
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Response of corrugated interface on incident qSV-wave in monoclinic elastic half-spaces
Autorzy:
Singh, S. S.
Lalvohbika, J.
Powiązania:
https://bibliotekanauki.pl/articles/264383.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
współczynnik odbicia
współczynnik transmisji
prędkość fazowa
qSV and qP-waves
reflection and transmission coefficients
monoclinic medium
corrugated interface
phase velocity
Opis:
This paper is concerned with the problem of reflection and transmission of elastic waves due to an incident plane qSV-wave at a corrugated interface between two dissimilar monoclinic elastic half-spaces. Due to the corrugated nature of the interface, there exist regularly and irregularly reflected and transmitted elastic waves. Using Rayleigh’s method of approximation, the reflection and transmission coefficients of regular and irregular waves are obtained for the first order of approximation. We have found that these coefficients are functions of the angle of incidence, elastic constants, corrugation and the frequency parameter. These coefficients are obtained for a special type of interface, z =dcos py. We have computed these coefficients for a particular model and discussed the effects of corrugation and frequency parameter.
Źródło:
International Journal of Applied Mechanics and Engineering; 2018, 23, 3; 727-750
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Propagation of spherical shock waves in a dusty gas with radiation heat-flux
Propagacja sferycznych fal uderzeniowych w zanieczyszczonym gazie z uwzględnieniem radiacyjnej wymiany ciepła
Autorzy:
Singh, K. K.
Vishwakarma, J. P.
Powiązania:
https://bibliotekanauki.pl/articles/281502.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
fale uderzeniowe
radiacyjna wymiana ciepła
shock waves
radiation heat-flux
Opis:
The propagation of spherical shock waves in a dusty gas with radiation heat-flux and exponentially varying density is investigated in the paper. The equilibrium flow conditions are assumed to be maintained, and the radiation is considered to be of a diffusion type for an optically thick grey gas model. The shock wave moves wit h variable velocity and the total energy of the wave is non-constant. Non-similar solutions are obtained, and the effects of variation of the radiation parameter and time are investigated. The effects of an increase in (i) the mass concentration of solid particles in the mixture and (ii) of the ratio of the density of solid particles to the initial density of gas on the flow variables in the region behind the shock are also investigated.
W pracy zajęto się problemem propagacji sferycznych fal uderzeniowych o wykładniczym rozkładzie gęstości w zanieczyszczonym gazie z uwzględnieniem radiacyjnej wymiany ciepła. Założono równowagowe warunki przepływu czynnika, a samą radiację przyjęto typu dyfuzyjnego w modelu optycznie nieprzezroczystego gazu. Fala uderzeniowa przemieszcza się ze zmienną prędkością, a całkowita energia fali również się zmienia. W analizie otrzymano rozwiązania niepodobne przy rozważaniu wpływu czasu i zmienności strumienia radiacji. Zbadano ponadto efekt wzrostu koncentracji masy cząstek stałych zanieczyszczenia oraz stosunku gęstości tych cząstek do początkowej gęstości gazu na parametry przepływu w obszarze bezpośrednio za czołem fali.
Źródło:
Journal of Theoretical and Applied Mechanics; 2007, 45, 4; 801-817
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of a dual-slot waveguide for a refractive index biosensor
Autorzy:
Sahu, S.
Ali, J.
Singh, G.
Powiązania:
https://bibliotekanauki.pl/articles/173377.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
biosensor
evanescent field
eigenmode
dispersion
Opis:
The present article illustrates the modeling and optimization of a dual-slot waveguide for the application of a refractive index biosensor. The nanometer scale waveguide structure uses the silicon-on-insulator platform for the consideration of higher sensitivity and compactness of a resonator biosensor. The modal analysis is performed using the finite difference method based on full vector eigenmode calculation. The maximum field penetration in the lower index region is found for the quasi-TE mode. The sensitivity is maximized through the optimization of the waveguide dimension by relating effective refractive index with the dispersion of a waveguide. The biosensor showed the maximum calculated sensitivity of 461.327 nm/RIU and a limit-of-detection of 2.601 × 10–6 RIU (where RIU denotes refractive index unit).
Źródło:
Optica Applicata; 2018, 48, 1; 161-167
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Molecular Interaction Study of Binary Mixtures of THF with Methanol and o-Cresol - an Optical and Ultrasonic Study
Autorzy:
Parveen, S.
Singh, S.
Shukla, D.
Singh, K.
Gupta, M.
Shukla, J.
Powiązania:
https://bibliotekanauki.pl/articles/1585019.pdf
Data publikacji:
2009-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.35.+d
62.60.+v
82.60.Lf
Opis:
The refractive indices, densities and ultrasonic velocities of binary liquid mixtures of tetrahydrofuran (THF) with methanol and o-cresol over the entire composition range have been measured at 293, 303 and 313 K. Refractive index, density and ultrasonic velocity data have been used to evaluate the molar refraction deviation $ΔR_{m}$, deviation in ultrasonic velocity Δu, excess internal pressure $π_{i}^{E}$, excess molar enthalpy $H_{m}^{E}$ and excess free volume $V_{f}^{E}$. The computed results of $ΔR_{m}$, Δu, $π_{i}^{E}$, $H_{m}^{E}$ and $V_{f}^{E}$ were fitted to the Redlich-Kister polynomial equation. These results suggest that specific strong interactions are taking place in THF + o-cresol mixture while dispersive forces seem to be responsible for behaviour of THF + methanol mixture. Further, experimental refractive index and density data of these mixtures were also used to test the validity of the empirical/semi-empirical relations and models for refractive index and density, respectively.
Źródło:
Acta Physica Polonica A; 2009, 116, 6; 1011-1017
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quasi Locally Connected Spaces and Pseudo Locally Connected Spaces
Autorzy:
Kohli, J.K.
Singh, D.
Tyagi, B. K.
Powiązania:
https://bibliotekanauki.pl/articles/746262.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
almost (quasi, pseudo) locally connected space
regular open set
regular \(F_\sigma\)-set
\(\theta\)-open set
\(D_\delta\)-completely regular space
quasi \(\theta\)-continuous function
coreflective subcategory
Opis:
Two new generalizations of locally connected spaces called ‘quasi locally connected spaces’ and ‘pseudo locally connected spaces’ are introduced and their basic properties are studied. The class of quasi locally connected spaces properly contains the class of almost locally connected spaces (J. Austral. Math. Soc. 31(1981), 421–428) and is strictly contained in the class of pseudo locally connected spaces which in its turn is properly contained in the class of sum connected spaces (Math. Nachrichten 82(1978), 121-129; Ann. Acad. Sci. Fenn. A I Math. 3(1977), 185–205). Product and subspace theorems for quasi (pseudo) locally connected spaces are discussed. Their preservation under mappings and their interplay with mappings are outlined. Function spaces of quasi (pseudo) locally connected spaces are considered. Change of topology of a quasi (pseudo) locally connected space is considered so that it is simply a locally connected space in the coarser topology. In contradistinction with almost locally connected spaces, quasi (pseudo) locally connected spaces constitute a coreflective subcategory of TOP.
Źródło:
Commentationes Mathematicae; 2010, 50, 2
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-25 z 49

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