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Robust stability criteria for uncertain linear systems with interval time-varying delay

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控制理论与应用（英文版） 2011年第4期9卷 559-566页

作者： Krishnan RAMAKRISHNAN Goshaidas ray Department of Electrical Engineering Indian Institute of Technology Kharagpur

This paper considers the robust delay-dependent stability problem of a class of linear uncertain system with interval time-varying delay and proposes less conservative stability criteria for computing the maximum allowable bound of the delay range. Less conservatism of the proposed stability criteria is attributed to the delay-central point method of stability analysis, wherein the delay interval is partitioned into two subintervals of equal length, and the time derivative of a candidate Lyapunov-Krasovskii functional based on delay decomposition technique is evaluated in each of these delay segments. In deriving the stability conditions in LMI framework, neither model transformations nor bounding techniques using free-weighting matrix variables are employed for dealing the cross-terms that emerge from the time derivative of the Lyapunov-Krasovskii functional; instead, they are dealt using tighter integral inequalities. The proposed analysis subsequently yields a stability condition in convex LMI framework that can be solved using standard numerical packages. For deriving robust stability conditions, two categories of system uncertainties, namely, time-varying structured and polytopic-type uncertainties, are considered. The effectiveness of the proposed stability criteria is validated through standard numerical examples.

关键词： Lyapunov-Krasovskii functional Robust stability Interval time-delay Delay-range-dependent stability Linear matrix inequality

f(■,L(X))-gravity in the context of dark energy with power law expansion and energy conditions

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Chinese Physics C 2023年第2期 194-211页

作者： Goutam Manna Arijit Panda Aninda Karmakar Saibal ray Md.Rabiul Islam Department of Physics Prabhat Kumar College Department of Physics Raiganj University Centre for Cosmology Astrophysics and Space Science (CCASS) GLA University

The objective of this work is to generate a general formalism of f(R,L(X))-gravity in the context of dark energy under the framework of K-essence emergent geometry with the Dirac-Born-Infeld(DBI) variety of action,where R is the familiar Ricci scalar,L(X) is the DBI type non-canonical Lagrangian with X=1/2gμν▽μφ▽νφ,and φ is the K-essence scalar *** emergent gravity metric(Gμν) and the well known gravitational metric(gμν)are not conformally *** have constructed a modified field equation using the metric formalism in f(R,L(X))-gravity incorporating the corresponding Friedmann equations into the framework of the background gravitational metric,which is of Friedmann-Lemaitre-Robertson-Walker(FLRW) *** solution of the modified Friedmann equations have been deduced for the specific choice of f(R,L(X)),which is of Starobinsky-type,using the power law expansion *** consistency of the model with the accelerating phase of the universe has been shown when we restrict ourselves to consider the value of the dark energy density as φ2=8/9=0.888 <1,which indicates that the present universe is dark-energy *** plots for the energy density(ρ),pressure(p),and equation of state parameter(ω) with respect to(w.r.t.) time(t) based on parametric values are interestingly consistent with the dark energy domination theory,and hence the accelerating *** also highlight the corresponding energy conditions and constraints of the f(R,L(X)) theory with a basic example.

关键词： modified theories of gravity dark energy K-essence model Friedman equations energy conditions

Review and Analysis: United States Secret Wars in Cambodia: Long-Term Impacts and Consequences

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Open Journal of Soil Science 2023年第7期13卷 295-328页

作者： Kenneth ray Olson David Richard Speidel College of Agricultural Consumer and Environmental Sciences University of Illinois Urbana USA USDA Resource Conservationist and Agricultural Consultant with Natural Resource Conservation Service and Foreign Agricultural Service Benton USA

The People’s Army of Vietnam (PAVN) decided to use conventional warfare to unify Vietnam. The United States military operation against the Ho Chi Minh Trail traffic began in 1959. The (PAVN) connected a series of old trails leading from North Vietnam to South Vietnam via Laos and Cambodia. In the 1960s the network of trails was expanded. Trail traffic was interdicted by repeated CIA (Air America) and US Air Force (Operation Ranch Hand) tactical herbicide spraying and bombing missions. During the late 1960s, the Khmer Rouge Army slowly grew in eastern Cambodia during a time when America was spraying and bombing the Ho Chi Minh Trail. On February 22, 1969, the PAVN launched a new offensive against American forces in South Vietnam from their sanctuaries in Cambodia. President Richard Nixon and Dr. Henry Kissinger, decided to spray and bomb Cambodia, a neutral country, to eliminate the PAVN sanctuary base camps. The damage and loss of life as a result of U.S. air campaign resulted in the insurgency (Khmer Rouge) being able to recruit civilian members. This created a dual effect of strengthening the popularity of the Khmer Rouge, led by Pol Pot, enabling him to overthrow the Khmer Republic in 1975. The primary objectives of this study are to determine the political impacts and consequences of: 1) the 1959 United States secret war on the Ho Chi Minh Trail in Cambodia and 2) the 1969 President Nixon’s decision to destroy the PAVN bases hidden in the Cambodian jungles. These United States secret wars in Cambodia had long-lasting effects on Cambodian political, social, and economic stability.

关键词： Ho Chi Minh Trail Khmer Rouge Cambodia Secret American War Pol Pot Killing Fields

Geochemistry of Harappan potteries from Kalibangan and sediments in the Ghaggar River： Clues for a dying river

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Geoscience Frontiers 2018年第4期9卷 1203-1211页

作者： Anirban Chatterjee Jyotiranjan S.ray Physical Research Laboratory Ahmedabad India

The ephemeral Ghaggar-Hakra River of northwestern India has always been considered to be the remnant of an ancient perennial glacier-fed river（Vedic Saraswati）. The exact reason and timing of major hydrological change of this river remains speculative. The river＇s purported association with the zenith of the Harappan civilisation remains a conjecture because the timings of its fluvial past are still being debated. In this study we have made an attempt to resolve this issue using geochemical provenance of sediments from some dated horizons in the Ghaggar flood plain and that of the material used in the potteries from the Mature Harappan period（4600-3900 yr BP） at Kalibangan. Sampled sedimentary horizons were dated by radiocarbon and optically stimulated luminescence（OSL） methods. Results of our study from the Ghaggar alluvium indicate that the river did have glacial sources during the early Holocene. However, the data from the potteries suggest that during the Mature Harappan period, the sediments in the Ghaggar as used by the potters did not have a higher Himalayan provenance and hence, were not derived from glaciated *** findings imply that during the time of the Mature Harappans the Ghaggar had already become a foothill-fed river.

关键词： Ghaggar alluvium Holocene Sediment provenance Mature Harappan pottery Geochemistry Vedic Saraswati

Ferromagnetism and ferroelectricity in a superlattice of antiferromagnetic perovskite oxides without ferroelectric polarization

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npj Computational Materials 2023年第1期9卷 632-637页

作者： Paresh C.Rout Avijeet ray Udo Schwingenschlögl Physical Sciences and Engineering Division(PSE) King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

We study the structural,electronic,and magnetic properties of the SrCrO_(3)/YCrO_(3) superlattice and their dependence on epitaxial *** discover that the superlattice adopts A-type antiferromagnetic(A-AFM)ordering in contrast to its constituents(SrCrO_(3):C-AFM;YCrO_(3):G-AFM)and retains it under compressive strain while becoming ferromagnetic(5μB per formula unit)at+1%*** obtained ferroelectric polarization is significantly higher than that of the R2NiMnO6/La2NiMnO6(R=Ce to Er)series of superlattices[***.5,4021(2014)]due to a large difference between the antipolar displacements of the Sr and Y *** superlattice is a hybrid-improper multiferroic material with a spontaneous ferroelectric polarization(13.5μC/cm^(2))approaching that of bulk BaTiO_(3)(19μC/cm^(2)).The combination of ferromagnetism with ferroelectricity enables multistate memory *** addition,the charge-order-driven p-type semiconducting state of the ferromagnetic phase(despite the metallic nature of SrCrO_(3))is a rare property and interesting for *** Carlo simulations demonstrate a magnetic critical temperature of 90 K for the A-AFM phase without strain and of 115 K for the ferromagnetic phase at+5%strain,for example.

关键词： ferroelectric superlattice ferromagnetic

Source Code Prioritization Using Forward Slicing for Exposing Critical Elements in a Program

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Journal of Computer Science & Technology 2011年第2期26卷 314-327页

作者： Mitrabinda ray Kanhaiya lal Kumawat Durga Prasad Mohapatra Department of Computer Science and Engineering National Institute of Technology

Even after thorough testing, a few bugs still remain in a program with moderate complexity. These residual bugs are randomly distributed throughout the code. We have noticed that bugs in some parts of a program cause frequent and severe failures compared to those in other parts. Then, it is necessary to take a decision about what to test more and what to test less within the testing budget. It is possible to prioritize the methods and classes of an object-oriented program according to their potential to cause failures. For this, we propose a program metric called influence metric to find the influence of a program element on the source code. First, we represent the source code into an intermediate graph called extended system dependence graph. Then, forward slicing is applied on a node of the graph to get the influence of that node. The influence metric for a method m in a program shows the number of statements of the program which directly or indirectly use the result produced by method m. We compute the influence metric for a class c based on the influence metric of all its methods. As influence metric is computed statically, it does not show the expected behavior of a class at run time. It is already known that faults in highly executed parts tend to more failures. Therefore, we have considered operational profile to find the average execution time of a class in a system. Then, classes are prioritized in the source code based on influence metric and average execution time. The priority of an element indicates the potential of the element to cause failures. Once all program elements have been prioritized, the testing effort can be apportioned so that the elements causing frequent failures will be tested thoroughly. We have conducted experiments for two well-known case studies -- Library Management System and Trading Automation System -- and successfully identified critical elements in the source code of each case study. We have also conducted experiments to compar

关键词： program slice extended system dependence graph influence of a class test priority

Better Use of Data to Define Nutrition Priority and Action

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Biomedical and Environmental Sciences 2001年第1期14卷 61-65页

作者： ray YIP Senior Adviser Health Nutrition UNICEF Area Office for China and Mongolia

Nutrition and dietary survey data has been useful in defining the magnitude of malnutrition and dietary deficit. Such information has been helpful in gaining attention to support or to do more to improve nutrition advocacy. However, there are also greater opportunities to use the common data to guide the program action. In summary, we have plenty of good nutrition and dietary information available to us in the planning and operation of nutrition intervention program. If we go beyond the use of data to justify area or subject of engagement, we can also use the same data for more efficient and more effective program without additional cost to us.

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Natural therapeutics for cancer treatment:success,challenges,and prospect

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Journal of Bio-X Research 2023年第2期6卷 61-72页

作者： Debasmita Dubey Shakti Rath Rajesh Kumar Meher Sanghamitra Mishra Soumya Surath Panda Subhashree ray Subrat Kumar Tripathy Medical Research Laboratory IMS and SUM HospitalSiksha“O”Anusandhan Deemed to be UniversityK8Kalinga NagarBhubaneswar 751003OdishaIndia Central Research Laboratory Institute of Dental SciencesSiksha“O”Anusandhan Deemed to be UniversityK8Kalinga NagarBhubaneswar 751003OdishaIndia Centre of Excellence in Natural Products and Therapeutics Department of Biotechnology and BioinformaticsSambalpur UniversityJyotiviharBurlaSambalpurOdishaIndia Department of Critical Care Medicine IMS and SUM HospitalSiksha“O”Anusandhan Deemed to be UniversityK8Kalinga NagarBhubaneswar 751003OdishaIndia Department of Oncology IMS and SUM HospitalSiksha“O”Anusandhan Deemed to be UniversityK8Kalinga NagarBhubaneswar 751003OdishaIndia Department of Biochemistry IMS and SUM HospitalSiksha“O”Anusandhan Deemed to be UniversityK8Kalinga NagarBhubaneswar-751003OdishaIndia.

Cancer is a terrifying disease that has become one of the world’s most challenging health concerns,necessitating a proactive approach to its *** is a rich source of new chemical entities and a promising avenue for cancer *** of their different modes of action on target events in many ways,nature-derived chemicals are considered good possibilities for anticancer drug *** current review article highlights recent breakthroughs in cancer therapeutics,including natural therapeutic molecules and their mechanisms of action against cancer treatment,as well as their limits,challenges,and *** the review,article data have been collected from previously studied and published research reports,clinical evaluations,case studies,and clinical statistical data generated by scientific research organizations of *** chemical structures have been drawn using computational software(chemsketch).The development of promising candidates that can prevent or reduce the proliferation of cancer cells without causing adverse effects from these therapeutics is now ***,nature-derived products are a game-changer because they are simple,safer,environmentally friendly,low-cost,quick,and less toxic than traditional treatment ***,many bioactive chemicals and their analogs have been discovered as possible anticancer treatment *** the review,the potent therapeutics phytochemicals derived from nature with their tremendous anticancer effects with limitations and prospects have been studied and analyzed based on previously published articles and reports.

关键词： cancer treatment chemotherapy drug resistance natural therapy toxicity

Understanding and reducing the fear of COVID-19

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2020年第9期21卷 752-754页

作者： Kwan Hoong NG ray KEMP Department of Biomedical Imaging University of MalayaKuala Lumpur 50603Malaysia ray Kemp Consulting BarringtonCambridgeCB227RRUK

The world is now plagued by a pandemic of unprecedented nature caused by a novel,emerging,and still poorly understood infectious disease,coronavirus disease 2019(COVID-19)(Wu and Mc Googan,2020).In addition to the rap... 详细信息

关键词： COV understood emerging