International Nuclear Information System (INIS)
Chang, Christopher; Alber, David; Graf, Peter; Kim, Kwiseon; Seibert, Michael
2007-01-01
The Genomics Revolution has resulted in a massive and growing quantity of whole-genome DNA sequences, which encode the metabolic catalysts necessary for life. However, gene annotations can rarely be complete, and measurement of the kinetic constants associated with the encoded enzymes can not possibly keep pace, necessitating the use of careful modeling to explore plausible network behaviors. Key challenges are (1) quantitatively formulating kinetic laws governing each transformation in a fixed model network; (2) characterizing the stable solution (if any) of the associated ordinary differential equations (ODEs); (3) fitting the latter to metabolomics data as it becomes available; and (4) optimizing a model output against the possible space of kinetic parameters, with respect to properties such as robustness of network response, or maximum consumption/production. This SciDAC-2 project addresses this large-scale uncertainty in the genome-scale metabolic network of the water-splitting, H 2 -producing green alga Chlamydomonas reinhardtii. Each metabolic transformation is formulated as an irreversible steady-state process, such that the vast literature on known enzyme mechanisms may be incorporated directly. To start, glycolysis, the tricarboxylic acid cycle, and basic fermentation pathways have been encoded in Systems Biology Markup Language (SBML) with careful annotation and consistency with the KEGG database, yielding a model with 3 compartments, 95 species, 38 reactions, and 109 kinetic constants. To study and optimize such models with a view toward larger models, we have developed a system which takes as input an SBML model, and automatically produces C code that when compiled and executed optimizes the model's kinetic parameters according to test criteria. We describe the system and present numerical results. Further development, including overlaying of a parallel multistart algorithm, will allow optimization of thousands of parameters on high-performance systems
Zhang, Meirong; Saberi, Ali; Stoorvogel, Antonie Arij
2015-01-01
This paper studies the synchronization problem for a network of identical discrete-time agents with unknown, nonuniform constant input delays. The agents are at most critically stable and non-introspective (i.e. the agents have no access to their own states or outputs). There exists full state
Town of Chapel Hill, North Carolina — Point features representing locations of all street addresses in Orange County, NC including Chapel Hill, NC. Data maintained by Orange County, the Town of Chapel...
Jarboe, Laura R
2018-01-04
Rational, predictive metabolic engineering of organisms requires an ability to associate biological activity to the corresponding gene(s). Despite extensive advances in the 20 years since the Escherichia coli genome was published, there are still gaps in our knowledge of protein function. The substantial amount of data that has been published, such as: omics-level characterization in a myriad of conditions; genome-scale libraries; and evolution and genome sequencing, provide means of identifying and prioritizing proteins for characterization. This review describes the scale of this knowledge gap, demonstrates the benefit of addressing the knowledge gap, and demonstrates the availability of interesting candidates for characterization. Copyright © 2017 Elsevier Ltd. All rights reserved.
Address Unknown: Homelessness in Contemporary America.
Wright, James D.
1989-01-01
While homelessness results from a variety of factors, ultimately its cause is an insufficient supply of suitable housing. The Federal government must massively intervene to halt the loss of additional low-income housing units, and benefits paid to the welfare-dependent population must approximately double. (MW)
International Nuclear Information System (INIS)
Foos, J.
1999-01-01
This paper is written in two tables. The first one describes the different particles (bosons and fermions). The second one gives the isotopes nuclear constants of the different elements, for Z = 1 to 56. (A.L.B.)
International Nuclear Information System (INIS)
Foos, J.
2000-01-01
This paper is written in two tables. The first one describes the different particles (bosons and fermions). The second one gives the isotopes nuclear constants of the different elements, for Z = 56 to 68. (A.L.B.)
International Nuclear Information System (INIS)
Foos, J.
1998-01-01
This paper is made of two tables. The first table describes the different particles (bosons and fermions) while the second one gives the nuclear constants of isotopes from the different elements with Z = 1 to 25. (J.S.)
International Nuclear Information System (INIS)
Foos, J.
1999-01-01
This paper is written in two tables. The first one describes the different particles (bosons and fermions). The second one gives the isotopes nuclear constants of the different elements, for Z = 56 to 68. (A.L.B.)
Cosmological constant as integration constant
Treder, H.-J.
1994-08-01
Einstein's field theory of elementary particles (Einstein 1919) yields black holes with a mass M approximately G-1 Lambda-1/2 c2 and a charge Q approximately G-1/2 Lambda-1/2 c2, their curvature radius is Lambda-1/2. Here Lambda is an integration constant of Einstein's 'trace-less' gravitation equations. The choice Lambda = G-1 h-1 c3 for this constant defines Planck ions and implies 'strong-gravity'. The choice Lambda = lambda = 3Hinf exp 2 c-2 (where Hinf means the Hubble parameter of a final de Sitter cosmos) involves 'weak-gravity' and describes an electro-vac spherical universe.
DEFF Research Database (Denmark)
Wilde, Danielle; Underwood, Jenny
2018-01-01
, to design towards unknown outcomes, using unknown materials. The impossibility of this task is proving as useful as it is disruptive. At its most potent, it is destabilising expectations, aesthetics and processes. Keeping the researchers, collaborators and participants in a state of unknowing, is opening...... the research potential to far-ranging possibilities. In this article we unpack the motivations driving the PKI project. We present our mixed-methodology, which entangles textile crafts, design interactions and materiality to shape an embodied enquiry. Our research outcomes are procedural and methodological...
Allocating monitoring effort in the face of unknown unknowns
Wintle, B.A.; Runge, M.C.; Bekessy, S.A.
2010-01-01
There is a growing view that to make efficient use of resources, ecological monitoring should be hypothesis-driven and targeted to address specific management questions. 'Targeted' monitoring has been contrasted with other approaches in which a range of quantities are monitored in case they exhibit an alarming trend or provide ad hoc ecological insights. The second form of monitoring, described as surveillance, has been criticized because it does not usually aim to discern between competing hypotheses, and its benefits are harder to identify a priori. The alternative view is that the existence of surveillance data may enable rapid corroboration of emerging hypotheses or help to detect important 'unknown unknowns' that, if undetected, could lead to catastrophic outcomes or missed opportunities. We derive a model to evaluate and compare the efficiency of investments in surveillance and targeted monitoring. We find that a decision to invest in surveillance monitoring may be defensible if: (1) the surveillance design is more likely to discover or corroborate previously unknown phenomena than a targeted design and (2) the expected benefits (or avoided costs) arising from discovery are substantially higher than those arising from a well-planned targeted design. Our examination highlights the importance of being explicit about the objectives, costs and expected benefits of monitoring in a decision analytic framework. ?? 2010 Blackwell Publishing Ltd/CNRS.
Bleeker-Rovers, C.P.; Meer, J.W.M. van der; Oyen, W.J.G.
2009-01-01
Fever of unknown origin (FUO) often is defined as a fever greater than 38.3 degrees C on several occasions during at least 3 weeks with uncertain diagnosis after a number of obligatory tests. In general, infection accounts for approximately one-fourth of cases of FUO, followed by neoplasm and
Inflammation in Heart Failure: known knowns and unknown unknowns.
Cocco, Giuseppe; Jerie, Paul; Amiet, Philipp; Pandolfi, Stefano
2017-08-01
The review deals with inflammation in heart failure (HF). Many data show that systemic inflammation is frequent in HF and implicate that inflammation contributes to damage and dysfunction of the cardiovascular system. Areas Covered: Experimental data have been mainly obtained in acute laboratory animal models. It is questionable whether animals' data can be translated into clinical settings with patients with chronic HF who have concomitant pathologies. The idea of a common inflammatory pathway that characterizes all different forms of clinical HF is unrealistic. It seems realistic that inflammation differs in non-cardiac and cardiac diseases. Research therapeutic options address the use of inhibitors of cytokines, of agents antagonizing oxidative stress, of MMP and of PI3K signaling pathways. Expert Opinion: Considering the many unknowns in our knowledge it is not surprising that early trials aimed to antagonize inflammation in HF have been disappointing. We are far away from having solid therapeutic schedules to use immunomodulation in all subtypes of HF. However, modern trials on HF due to virus infections have proven that immunomodulation is therapeutically effective. We should wisely use the known facts and accept that we have many unknowns. By appropriate selection of the subtypes of HF we may be able to find the appropriate therapy against inflammation in HF.
Cervicitis of unknown etiology.
Taylor, Stephanie N
2014-07-01
Cervicitis has been described by some as the female counterpart of urethritis in men. Over the years a number of clinical and microscopy-based definitions have been suggested in the literature. Clinical manifestations include mucopurulent discharge from the cervix, cervical friability (easy bleeding from the cervix with passage of a swab) and cervical ectopy. Microscopic definitions involving the use of Gram stain of cervical secretions have included either more than 10 white blood cells (WBCs) or more than 30 WBCs per high-power field. Combinations of these clinical and microscopic findings have been used in attempts to increase the accuracy of cervicitis diagnosis. When cervicitis was initially recognized as a clinical entity, several investigators reported the primary pathogens causing cervicitis as Neisseria gonorrhoeae and Chlamydia trachomatis. It is now well established that most cases of cervicitis are not caused by these two organisms. Most cases of cervicitis are of unknown etiology.
Grenier, E; Liksonov, V I; Tsinoiev, V G
2002-01-01
This article reports experiments concerning the study of the electrical explosion of a titanium foil in water. During the electrical discharge a strong luminescence appears, the analysis of spectra shows the presence of new chemical elements and this presence is confirmed by the mass-spectrometry measurements performed on the precipitates found after the discharge. This experiment has been repeated about 200 times and the results are consistent an show an average titanium transmutation rate of 4%. Neither gamma nor neutron radiation have been detected but an unknown radiation, sensitive to magnetic fields, has been detected through tracks left on RF-ZMP fluo-graphical films covered with a 10 mu m-thick emulsion layer. The assumption of a radiation made up of magnetic monopoles is supported by the author. (A.C.)
Renormalization of Newton's constant
Falls, Kevin
2015-12-01
The problem of obtaining a gauge independent beta function for Newton's constant is addressed. By a specific parametrization of metric fluctuations a gauge independent functional integral is constructed for the semiclassical theory around an arbitrary Einstein space. The effective action then has the property that only physical polarizations of the graviton contribute, while all other modes cancel with the functional measure. We are then able to compute a gauge independent beta function for Newton's constant in d dimensions to one-loop order. No Landau pole is present provided Ng<18 , where Ng=d (d -3 )/2 is the number of polarizations of the graviton. While adding a large number of matter fields can change this picture, the absence of a pole persists for the particle content of the standard model in four spacetime dimensions.
International Nuclear Information System (INIS)
Ross, Priscilla.
1996-01-01
The present position and future potential of the Russian oil company Tatneft are assessed. Tatneft, the eighteenth largest oil company in the world, has 85 oil fields and over 20,700 production wells. In 1995, it increased its production by 6% to 504,000bpd and its crude oil exports outside Russia were 213,000bpd. The company forms the basis of the oil industry in the semi-autonomous republic of Tatarstan. Tafneft became a joint stock company in May 1994 with the government of Tatarstan as the largest shareholder with a 46% stake. Although Tafneft produces far more crude than Conoco or YPF, its market capitalisation per barrel of production is only 5% of these companies. Its long-term future lies in successfully increasing production and enhancing financial performance. The former is being addressed through enhanced oil recovery methods and various joint ventures are being entered into with western partners in order to tap foreign expertise and to finance modern equipment. The achievement of the latter requires an improvement towards world prices of the price for Russian domestic crude and a reduction in the tax burden away from revenue towards a profits basis. (UK)
Garbers, C. F.
1987-09-01
Ladies and gentlemen, it is indeed a great privilege and pleasure for me to present the opening address at this, the 17th International Congress on High Speed Photograpy and Photonics. Before turning to the business of the Congress, I would like to briefly introduce you to South Africa: its scientific past and its research challenges for the future.
African Journals Online (AJOL)
Your Excellency. Honoured Guests. Members of the Association. It is my duty and pleasure to thank H.E. Lij. Endalkatchew Makonnen for the fine address with which he has opened this First National Conference of the EAEA. He has pointedly reminded us that though. Engineers and Architects play a key role, develop-.
International Nuclear Information System (INIS)
Ianko, L.
1993-01-01
This short talk was the opening remarks to the attendees at this conference, presented by the Scientific Secretary, IWG-LMNPP, of the IAEA. This meeting is an effort to aid research on problems related to the general area of nuclear plant aging and life management. In particular it addresses fracture properties of reactor materials and components, both as installed, and at end of service condition. A major concern is relating measurements made on laboratory samples to properties displayed by actual reactor components
Zakaria, R
1996-07-01
By means of this graduation address at the International Institute for Population Sciences (IIPS) in Bombay, the Chancellor of Urdu University voiced his concerns about overpopulation in India. During the speaker's tenure as Health Minister of Maharashtra, he implemented a sterilization incentive program that resulted in the state's having the best family planning (FP) statistics in India for almost 10 years. The incentive program, however, was misused by overenthusiastic officials in other states, with the result that the FP program was renamed the Family Welfare Programme. Population is growing in India because of improvements in health care, but the population education necessary to change fertility will require more time than the seriousness of the population problem allows. In the longterm, poverty and illiteracy must be addressed to control population. In the meanwhile, the graduate program at the IIPS should be expanded to include an undergraduate program, marriage age laws should be enforced, and misconceptions about religious objections to FP must be addressed. India can not afford to use the measures forwarded by developed countries to control population growth. India must integrate population control efforts with the provision of health care because if population continues to grow in the face of reduced infant mortality and longer life expectancy, future generations will be forced to live in a state of poverty and economic degradation.
Unknown foundation determination for scour.
2012-04-01
Unknown foundations affect about 9,000 bridges in Texas. For bridges over rivers, this creates a problem : regarding scour decisions as the calculated scour depth cannot be compared to the foundation depth, and a : very conservative costly approach m...
Joshi, P. S.
2014-03-01
From jets to cosmos to cosmic censorship P S Joshi Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India E-mail: psj@tifr.res.in 1. Introduction At the outset, I should like to acknowledge that part of the title above, which tries to capture the main flavour of this meeting, and has been borrowed from one of the plenary talks at the conference. When we set out to make the programme for the conference, we thought of beginning with observations on the Universe, but then we certainly wanted to go further and address deeper questions, which were at the very foundations of our inquiry, and understanding on the nature and structure of the Universe. I believe, we succeeded to a good extent, and it is all here for you in the form of these Conference Proceedings, which have been aptly titled as 'Vishwa Mimansa', which could be possibly translated as 'Analysis of the Universe'! It is my great pleasure and privilege to welcome you all to the ICGC-2011 meeting at Goa. The International Conference on Gravitation and Cosmology (ICGC) series of meetings are being organized by the Indian Association for General Relativity and Gravitation (IAGRG), and the first such meeting was planned and conducted in Goa in 1987, with subsequent meetings taking place at a duration of about four years at various locations in India. So, it was thought appropriate to return to Goa to celebrate the 25 years of the ICGC meetings. The recollections from that first meeting have been recorded elsewhere here in these Proceedings. The research and teaching on gravitation and cosmology was initiated quite early in India, by V V Narlikar at the Banares Hindu University, and by N R Sen in Kolkata in the 1930s. In course of time, this activity grew and gained momentum, and in early 1969, at the felicitation held for the 60 years of V V Narlikar at a conference in Ahmedabad, P C Vaidya proposed the formation of the IAGRG society, with V V Narlikar being the first President. This
Rao, L
1984-01-01
Stressed in this address is the crucial stage of the population boom, peeculiar to developing countries. The phenomenal rise in India's population, over the last 10 years, is particularly emphasized as it may thwart attempts for socioeconnomic development. Population and development are congruent concerns which need to be pursued simultaneously, and family planning must be accorded the highest priority in national efforts. In its attempts to curb its population explosion, India has witnessed significant progress in health and family welfare work in its march towards the goal of health for all. Recently, the focus has been on primary health care with its emphasis on prevention against risk of disease. The key element of the goal of health for all is the provision of primary health care to all, especially those who are poor. The new 20-Point Programme of India pinpoints areas of special thrust which show immediate tangible results in health and family welfare and the increase of primary health care facilities. Family planning is discussed as a people's movement in which the government's role is that of educator in contraceptive methodds so the people can be motivated to choose, on their own, anyone of them. Trained government personnel, service facilities and contraceptive supplies are being promoted for that goal. The energies of all social, political, religious and cultural organizations have to be channelled and utilized in the process of educating the people and making them adopt the small family norm. Graduates are urged to utilize their knowledge in the service of their country.
Ghatowar, P S
1993-07-01
The Union Deputy Minister of Health and Family Welfare in India addressed the 35th convocation of the International Institute for Population Sciences in Bombay in 1993. Officials in developing countries have been concerned about population growth for more than 30 years and have instituted policies to reduce population growth. In the 1960s, population growth in developing countries was around 2.5%, but today it is about 2%. Despite this decline, the world will have 1 billion more individuals by the year 2001. 95% of these new people will be born in developing countries. India's population size is so great that India does not have the time to wait for development to reduce population growth. Population needs to be viewed as an integrated part of overall development, since it is linked to poverty, illiteracy, environmental damage, gender issues, and reproductive health. Despite a large population size, India has made some important advancements in health and family planning. For example, India has reduced population growth (to 2.14% annually between 1981-1991), infant mortality, and its birth rate. It has increased the contraceptive use rate and life expectancy. Its southern states have been more successful at achieving demographic goals than have the northern states. India needs to implement efforts to improve living conditions, to change attitudes and perceptions about small families and contraception, and to promote family planning acceptance earlier among young couples. Improvement of living conditions is especially important in India, since almost 33% of the people live in poverty. India needs to invest in nutrition, health, and education. The mass media and nongovernmental organizations need to create population awareness and demand for family planning services. Improvement in women's status accelerates fertility decline, as has happened in Kerala State. The government needs to facilitate generation of jobs. Community participation is needed for India to achieve
International Nuclear Information System (INIS)
Davis, J.M.
1991-01-01
DOE biomass R ampersand D programs have the potential to provide America with both plentiful, clean-burning domestic transportation fuels and cost-competitive industrial and utility fuels, benefiting energy security in the United States. Biofuels developed under our programs will also help improve air quality, reduce greenhouse gases, reduce the large daily quantities of waste we produce, and revitalize rural America. These research motivations have been documented in the National Energy Strategy. DOE looks forward to expanding its biofuels research program and to forging a partnership with private sector for cost-shared commercialization of new fuels and vehicle technologies. Many alternative fuels (e.g., ethanol, methanol, compressed natural gas, propane, or electricity) are candidates for gaining market share. Indeed, there may be significant regional variation in the future fuel mix. Alcohol fuels from biomass, particularly ethanol, have the potential to make a major contribution. Currently, ethanol in the United States is almost entirely made from corn; and the limitations of that process are well known (e.g., costly feedstock, end product requiring subsidy to be competitive, use of fossil fuels in renewable feedstock production and processing, and potential adverse impact of corn ethanol production on the price of food). To address these concerns, the DOE biofuels program is pursuing an ambitious research program to develop the technologies needed to convert these crops into alternative transportation fuels, primarily cellulose-based ethanol and methanol. Program R ampersand D has reduced the estimated cost per gallon of cellulose-based ethanol from $3.60 in 1980 to the current $1.35, with a program goal of $0.60 by the year 2000. DOE is also investigating the thermochemical conversion of biomass to methanol. The program goal is to achieve commercial production of methanol (like ethanol) at the gasoline equivalent of $0.90 per gallon by the year 2000. 4 figs
Ion exchange equilibrium constants
Marcus, Y
2013-01-01
Ion Exchange Equilibrium Constants focuses on the test-compilation of equilibrium constants for ion exchange reactions. The book first underscores the scope of the compilation, equilibrium constants, symbols used, and arrangement of the table. The manuscript then presents the table of equilibrium constants, including polystyrene sulfonate cation exchanger, polyacrylate cation exchanger, polymethacrylate cation exchanger, polysterene phosphate cation exchanger, and zirconium phosphate cation exchanger. The text highlights zirconium oxide anion exchanger, zeolite type 13Y cation exchanger, and
Kiku, H.
2014-12-01
Ladies and Gentlemen, It is an honor for me to present my welcome address in the 3rd International Workshop on "State of the Art in Nuclear Cluster Physics"(SOTANCP3), as the president of Kanto Gakuin University. Particularly to those from abroad more than 17 countries, I am very grateful for your participation after long long trips from your home to Yokohama. On the behalf of the Kanto Gakuin University, we certainly welcome your visit to our university and stay in Yokohama. First I would like to introduce Kanto Gakuin University briefly. Kanto Gakuin University, which is called KGU, traces its roots back to the Yokohama Baptist Seminary founded in 1884 in Yamate, Yokohama. The seminary's founder was Albert Arnold Bennett, alumnus of Brown University, who came to Japan from the United States to establish a theological seminary for cultivating and training Japanese missionaries. Now KGU is a major member of the Kanto Gakuin School Corporation, which is composed of two kindergartens, two primary schools, two junior high schools, two senior high schools as well as KGU. In this university, we have eight faculties with graduate school including Humanities, Economics, Law, Sciences and Engineering, Architecture and Environmental Design, Human and Environmental Studies, Nursing, and Law School. Over eleven thousands students are currently learning in our university. By the way, my major is the geotechnical engineering, and I belong to the faculty of Sciences and Engineering in my university. Prof. T. Yamada, here, is my colleague in the same faculty. I know that the nuclear physics is one of the most active academic fields in the world. In fact, about half of the participants, namely, more than 50 scientists, come from abroad in this conference. Moreover, I know that the nuclear physics is related to not only the other fundamental physics such as the elementary particle physics and astrophysics but also chemistry, medical sciences, medical cares, and radiation metrology
International Nuclear Information System (INIS)
Henrich, E.W.
2005-01-01
Full text: It is an honour for me to make this opening address on behalf of the European Commission which has cooperated with the International Atomic Energy Agency in organizing this Conference, and in particular on behalf of Hans Forsstroem from the Directorate-General, Research, who will arrive only later this week. Protection of the environment is, and will continue to be, an important consideration in the development and application of soundly based radiation protection standards. Current standards rest largely on the premise that, in protecting man, the environment is afforded an adequate level of protection. While this premise is broadly accepted by the radiation protection profession, it has come under increasing challenge in recent years. This challenge has not arisen because of any observable damage to the environment while operating within current standards. Rather, it has different origins including: - The robustness of the premise that protection of man affords protection of the environment, in particular the extent to which it is based on value judgements as opposed to rigorous scientific argument; - The more explicit inclusion of protection of the environment into national legislation on radiation protection and the need to demonstrate compliance; - A desire to achieve greater comparability between radiation and other pollutants. These trends were recognized by the Commission in the late 1990s and, as a result, the topic of protection of the environment was included as an important element of the European Union's 5th Research Framework Programme. Community support has been given to the FASSET project about which we will hear much during this Conference. This multinational project is providing much of the scientific basis underpinning and informing ongoing discussions on the development of a system of protection for the environment. Much, however, remains to be done to establish a well conceived and practicable system for protection of the environment
Gutierrez, M.
2011-01-01
In this article, the author describes his life experiences and how difficult it was for him as a Mexican immigrant living in the United States. His life changed when he moved to America, but his character changed when he started middle school. He had been constantly insulted by his classmates, and at the time he wanted to get revenge. The kids he…
Scalar-tensor cosmology with cosmological constant
International Nuclear Information System (INIS)
Maslanka, K.
1983-01-01
The equations of scalar-tensor theory of gravitation with cosmological constant in the case of homogeneous and isotropic cosmological model can be reduced to dynamical system of three differential equations with unknown functions H=R/R, THETA=phi/phi, S=e/phi. When new variables are introduced the system becomes more symmetrical and cosmological solutions R(t), phi(t), e(t) are found. It is shown that when cosmological constant is introduced large class of solutions which depend also on Dicke-Brans parameter can be obtained. Investigations of these solutions give general limits for cosmological constant and mean density of matter in plane model. (author)
Function analysis of unknown genes
DEFF Research Database (Denmark)
Rogowska-Wrzesinska, A.
2002-01-01
This thesis entitled "Function analysis of unknown genes" presents the use of proteome analysis for the characterisation of yeast (Saccharomyces cerevisiae) genes and their products (proteins especially those of unknown function). This study illustrates that proteome analysis can be used...... be obtained using proteome analysis. Chapter 1 and 2 provide the basic theoretical aspects of proteome analysis, its principles, the main techniques involved and their use in the studies of the molecular biology of yeast cells. Chapter 3 presents the methods and tools involved in proteome analysis and used...... presents a comparison of the proteomes of three yeast wild type strains CEN.PK2, FY1679 and W303 that are widely used in function analysis projects and proves that FY1679 and W303 strains are more similar to each other than to the CEN.PK2 strain. This study identifies 62 proteins that are differentially...
Desquamative Inflammatory Vaginitis: The Unknown
María Trinidad Alumbreros Andújar; Ana González López; Celia Pérez Parra; Rafael López Pérez; Carmen Céspedes Casas; María Mercedes Ramírez Gómez; Castor Martin Francisco; Francisco Javier Haya Palazuelos
2015-01-01
Introduction: Desquamative inflammatory vaginitis (DIV) is a chronic inflammatory process of unknown etiology, characterized by genital pain and profuse vaginal discharge, mainly affecting perimenopausal women. It is an entity little known by clinicians, leading to a delay in diagnosis and the consequent alteration of the patients’ quality of life. The aim in this manuscript is to analyze DIV through the review of a case and the scientific literature. Case presentation: We report the case ...
A natural cosmological constant from chameleons
Directory of Open Access Journals (Sweden)
Horatiu Nastase
2015-07-01
Full Text Available We present a simple model where the effective cosmological constant appears from chameleon scalar fields. For a Kachru–Kallosh–Linde–Trivedi (KKLT-inspired form of the potential and a particular chameleon coupling to the local density, patches of approximately constant scalar field potential cluster around regions of matter with density above a certain value, generating the effect of a cosmological constant on large scales. This construction addresses both the cosmological constant problem (why Λ is so small, yet nonzero and the coincidence problem (why Λ is comparable to the matter density now.
A natural cosmological constant from chameleons
Energy Technology Data Exchange (ETDEWEB)
Nastase, Horatiu, E-mail: nastase@ift.unesp.br [Instituto de Física Teórica, UNESP-Universidade Estadual Paulista, R. Dr. Bento T. Ferraz 271, Bl. II, Sao Paulo 01140-070, SP (Brazil); Weltman, Amanda, E-mail: amanda.weltman@uct.ac.za [Astrophysics, Cosmology & Gravity Center, Department of Mathematics and Applied Mathematics, University of Cape Town, Private Bag, Rondebosch 7700 (South Africa)
2015-07-30
We present a simple model where the effective cosmological constant appears from chameleon scalar fields. For a Kachru–Kallosh–Linde–Trivedi (KKLT)-inspired form of the potential and a particular chameleon coupling to the local density, patches of approximately constant scalar field potential cluster around regions of matter with density above a certain value, generating the effect of a cosmological constant on large scales. This construction addresses both the cosmological constant problem (why Λ is so small, yet nonzero) and the coincidence problem (why Λ is comparable to the matter density now)
A natural cosmological constant from chameleons
International Nuclear Information System (INIS)
Nastase, Horatiu; Weltman, Amanda
2015-01-01
We present a simple model where the effective cosmological constant appears from chameleon scalar fields. For a Kachru–Kallosh–Linde–Trivedi (KKLT)-inspired form of the potential and a particular chameleon coupling to the local density, patches of approximately constant scalar field potential cluster around regions of matter with density above a certain value, generating the effect of a cosmological constant on large scales. This construction addresses both the cosmological constant problem (why Λ is so small, yet nonzero) and the coincidence problem (why Λ is comparable to the matter density now)
Indian Academy of Sciences (India)
IAS Admin
The article discusses the importance of the fine structure constant in quantum mechanics, along with the brief history of how it emerged. Al- though Sommerfelds idea of elliptical orbits has been replaced by wave mechanics, the fine struc- ture constant he introduced has remained as an important parameter in the field of ...
Directory of Open Access Journals (Sweden)
Carroll Sean M.
2001-01-01
Full Text Available This is a review of the physics and cosmology of the cosmological constant. Focusing on recent developments, I present a pedagogical overview of cosmology in the presence of a cosmological constant, observational constraints on its magnitude, and the physics of a small (and potentially nonzero vacuum energy.
On Aryabhata's Planetary Constants
Kak, Subhash
2001-01-01
This paper examines the theory of a Babylonian origin of Aryabhata's planetary constants. It shows that Aryabhata's basic constant is closer to the Indian counterpart than to the Babylonian one. Sketching connections between Aryabhata's framework and earlier Indic astronomical ideas on yugas and cyclic calendar systems, it is argued that Aryabhata's system is an outgrowth of an earlier Indic tradition.
Intraabdominal abscessus of unknown etiology
Directory of Open Access Journals (Sweden)
Čolović Radoje
2012-01-01
Full Text Available Introduction. Intraabdominal abscesses are in 98-99% cases the result of secondary and only in 1-2% of primary peritonitis. They are easy and successfully diagnosed. Abdominal abscesses of unknown cause are extremely rare. Case Outline. The authors present a 68-year-old man, without significant data in past history, who suddenly developed epigastric pain, nausea, vomiting and leukocytosis which was treated with antibiotics resulting in the alleviation of complaints and reduction of white blood cells count. After five days ultrasonography showed incapsulated collection of dense fluid in the epigastrium confirmed by CT scan two days later. Upper endoscopy excluded ulcer and/or perforation of the stomach and duodenum. Under local anesthesia, through the upper part of the left rectal muscle, puncture followed by incision was done, and about 50 ml of dense pus was removed. Finger exploration of the cavity showed no foreign body within the cavity. Using drainage, the recovery was quick and uneventful. By preoperative and postoperative abdominal investigations no cause of the abscess was found. Two and a half years after surgery the patient remained symptom-free with normal clinical, laboratory and ultrasonographic findings. Conclusion. The authors presented an intraabdominal abscess of unknown cause that was successfully treated with antibiotics, percutaneous puncture and drainage under local anaesthesia. In spite of all diagnostic methods the cause of the abscess could not be found. Thus, such a possibility, although being rare, should be taken into account.
The Unknown Component Problem Theory and Applications
Villa, Tiziano; Brayton, Robert K; Mishchenko, Alan; Petrenko, Alexandre; Sangiovanni-Vincentelli, Alberto
2012-01-01
The Problem of the Unknown Component: Theory and Applications addresses the issue of designing a component that, combined with a known part of a system, conforms to an overall specification. The authors tackle this problem by solving abstract equations over a language. The most general solutions are studied when both synchronous and parallel composition operators are used. The abstract equations are specialized to languages associated with important classes of automata used for modeling systems. The book is a blend of theory and practice, which includes a description of a software package with applications to sequential synthesis of finite state machines. Specific topologies interconnecting the components, exact and heuristic techniques, and optimization scenarios are studied. Finally the scope is enlarged to domains like testing, supervisory control, game theory and synthesis for special omega languages. The authors present original results of the authors along with an overview of existing ones.
The cosmological constant problem
International Nuclear Information System (INIS)
Dolgov, A.D.
1989-05-01
A review of the cosmological term problem is presented. Baby universe model and the compensating field model are discussed. The importance of more accurate data on the Hubble constant and the Universe age is stressed. 18 refs
Deconstructing the Cosmological Constant
Jejjala, V; Minic, D; Jejjala, Vishnu; Leigh, Robert G.; Minic, Djordje
2003-01-01
Deconstruction provides a novel way of dealing with the notoriously difficult ultraviolet problems of four-dimensional gravity. This approach also naturally leads to a new perspective on the holographic principle, tying it to the fundamental requirements of unitarity and diffeomorphism invariance, as well as to a new viewpoint on the cosmological constant problem. The numerical smallness of the cosmological constant is implied by a unique combination of holography and supersymmetry, opening a new window into the fundamental physics of the vacuum.
Peselnick, L.; Robie, R.A.
1962-01-01
The recent measurements of the elastic constants of calcite by Reddy and Subrahmanyam (1960) disagree with the values obtained independently by Voigt (1910) and Bhimasenachar (1945). The present authors, using an ultrasonic pulse technique at 3 Mc and 25??C, determined the elastic constants of calcite using the exact equations governing the wave velocities in the single crystal. The results are C11=13.7, C33=8.11, C44=3.50, C12=4.82, C13=5.68, and C14=-2.00, in units of 1011 dyncm2. Independent checks of several of the elastic constants were made employing other directions and polarizations of the wave velocities. With the exception of C13, these values substantially agree with the data of Voigt and Bhimasenachar. ?? 1962 The American Institute of Physics.
International Nuclear Information System (INIS)
Cohen, E.R.; Taylor, B.N.
1995-01-01
Present technological applications require the values used for the fundamental physical and chemical constants to be more and more precise and at the same time coherent. Great importance is then attached to the task of coordinating and comparing the most recent experimental data, extracting from them as a whole, by means of a least square fit, a set of values for the fundamental constants as precise and coherent as possible. The set of values which is at present in usage, derives from a fit performed in 1986, but new experimental results already promise a large reduction in the uncertainties of various constants. A new global fit that will implement such reductions is scheduled for completion in 1995 or 1996
Radiographic constant exposure technique
DEFF Research Database (Denmark)
Domanus, Joseph Czeslaw
1985-01-01
The constant exposure technique has been applied to assess various industrial radiographic systems. Different X-ray films and radiographic papers of two producers were compared. Special attention was given to fast film and paper used with fluorometallic screens. Radiographic image quality was tes...... was tested by the use of ISO wire IQI's and ASTM penetrameters used on Al and Fe test plates. Relative speed and reduction of kilovoltage obtained with the constant exposure technique were calculated. The advantages of fast radiographic systems are pointed out...
Radiographic constant exposure technique
DEFF Research Database (Denmark)
Domanus, Joseph Czeslaw
1985-01-01
The constant exposure technique has been applied to assess various industrial radiographic systems. Different X-ray films and radiographic papers of two producers were compared. Special attention was given to fast film and paper used with fluorometallic screens. Radiographic image quality...... was tested by the use of ISO wire IQI's and ASTM penetrameters used on Al and Fe test plates. Relative speed and reduction of kilovoltage obtained with the constant exposure technique were calculated. The advantages of fast radiographic systems are pointed out...
Education Through Exploration: Evaluating the Unknown
Anbar, A. D.
2015-12-01
Mastery of the peculiar and powerful practices of science is increasingly important for the average citizen. With the rise of the Internet, most of human knowledge is at our fingertips. As content becomes a commodity, success and survival aren't about who knows the most, but who is better able to explore the unknown, actively applying and extending knowledge through critical thinking and hypothesis-driven problem-solving. This applies to the economic livelihoods of individuals and to society at large as we grapple with climate change and other science-infused challenges. Unfortunately, science is too often taught as an encyclopedic collection of settled facts to be mastered rather than as a process of exploration that embraces curiosity, inquiry, testing, and communication to reduce uncertainty about the unknown. This problem is exacerbated by the continued prevalence of teacher-centric pedagogy, which promotes learning-from-authority and passive learning. The initial wave of massively open online courses (MOOCs) generally mimic this teaching style in virtual form. It is hypothesized that emerging digital teaching technologies can help address this challenge at Internet scale in "next generation" MOOCs and flipped classroom experiences. Interactive simulations, immersive virtual field trips, gamified elements, rapid adaptive feedback, intelligent tutoring systems, and personalized pathways, should motivate and enhance learning. Through lab-like projects and tutorials, students should be able to construct knowledge from interactive experiences, modeling the authentic practice of science while mastering complex concepts. Freed from lecturing, teaching staff should be available for direct and intense student-teacher interactions. These claims are difficult to evaluate with traditional assessment instruments, but digital technologies provide powerful new ways to evaluate student learning and learn from student behaviors. We will describe ongoing experiences with such
International Nuclear Information System (INIS)
O Murchadha, N.
1991-01-01
The set of riemannian three-metrics with positive Yamabe constant defines the space of independent data for the gravitational field. The boundary of this set is investigated, and it is shown that metrics close to the boundary satisfy the positive-energy theorem. (Author) 18 refs
FORMATION CONSTANTS AND THERMODYNAMIC ...
African Journals Online (AJOL)
, Ni(II), Cu(II) and Zn(II) ions has been ... A good deal of work has been reported on the preparation and structural investigation of. Schiff base ... Formation constants and thermodynamic parameters of Co, Ni, Cu and Zn complexes. Bull. Chem.
Address Points - Allegheny County Address Points 201601
NSGIC Education | GIS Inventory — This dataset contains Address Points in Allegheny County. The Address Points were created by GDR for the Allegheny County CAD project, October 2008. Data is updated...
Production in constant evolution
International Nuclear Information System (INIS)
Lozano, T.
2009-01-01
The Cofrentes Nuclear Power Plant now has 25 years of operation behind it: a quarter century adding value and demonstrating the reasons why it is one of the most important energy producing facilities in the Spanish power market. Particularly noteworthy is the enterprising spirit of the plant, which has strived to continuously improve with the large number of modernization projects that it has undertaken over the past 25 years. The plant has constantly evolved thanks to the amount of investments made to improve safety and reliability and the perseverance to stay technologically up to date. Efficiency, training and teamwork have been key to the success of the plant over these 25 years of constant change and progress. (Author)
Indian Academy of Sciences (India)
IAS Admin
important parameter in the field of atomic struc- ture. The values of the constants of ... tions in their core that produce carbon. As a result, .... atom in 1913. In other words, the size of a hydrogen atom is a factor α−2 ≈ 20000 times the size of an elec- tron. Another way of looking at α is to consider the ratio of the orbital speed of ...
International Nuclear Information System (INIS)
Mellor, F.
1989-01-01
Astronomical observations predict to an extremely accurate degree that the cosmological term in Einstein's equations should be zero. This conflicts with the predictions from particle theories of a non-zero cosmological term. Attempts to resolve this paradox range from arguments based on the anthropic principle to supersymmetric theories to quantum cosmological proposals. These approaches are discussed here and the history of the cosmological constant is reviewed. (author)
Connecting Fundamental Constants
International Nuclear Information System (INIS)
Di Mario, D.
2008-01-01
A model for a black hole electron is built from three basic constants only: h, c and G. The result is a description of the electron with its mass and charge. The nature of this black hole seems to fit the properties of the Planck particle and new relationships among basic constants are possible. The time dilation factor in a black hole associated with a variable gravitational field would appear to us as a charge; on the other hand the Planck time is acting as a time gap drastically limiting what we are able to measure and its dimension will appear in some quantities. This is why the Planck time is numerically very close to the gravitational/electric force ratio in an electron: its difference, disregarding a π√(2) factor, is only 0.2%. This is not a coincidence, it is always the same particle and the small difference is between a rotating and a non-rotating particle. The determination of its rotational speed yields accurate numbers for many quantities, including the fine structure constant and the electron magnetic moment
Jackson, Neal
2015-01-01
I review the current state of determinations of the Hubble constant, which gives the length scale of the Universe by relating the expansion velocity of objects to their distance. There are two broad categories of measurements. The first uses individual astrophysical objects which have some property that allows their intrinsic luminosity or size to be determined, or allows the determination of their distance by geometric means. The second category comprises the use of all-sky cosmic microwave background, or correlations between large samples of galaxies, to determine information about the geometry of the Universe and hence the Hubble constant, typically in a combination with other cosmological parameters. Many, but not all, object-based measurements give H 0 values of around 72-74 km s -1 Mpc -1 , with typical errors of 2-3 km s -1 Mpc -1 . This is in mild discrepancy with CMB-based measurements, in particular those from the Planck satellite, which give values of 67-68 km s -1 Mpc -1 and typical errors of 1-2 km s -1 Mpc -1 . The size of the remaining systematics indicate that accuracy rather than precision is the remaining problem in a good determination of the Hubble constant. Whether a discrepancy exists, and whether new physics is needed to resolve it, depends on details of the systematics of the object-based methods, and also on the assumptions about other cosmological parameters and which datasets are combined in the case of the all-sky methods.
Yongquan, Han
2016-10-01
The ideal gas state equation is not applicable to ordinary gas, it should be applied to the Electromagnetic ``gas'' that is applied to the radiation, the radiation should be the ultimate state of matter changes or initial state, the universe is filled with radiation. That is, the ideal gas equation of state is suitable for the Singular point and the universe. Maybe someone consider that, there is no vessel can accommodate radiation, it is because the Ordinary container is too small to accommodate, if the radius of your container is the distance that Light through an hour, would you still think it can't accommodates radiation? Modern scientific determinate that the radius of the universe now is about 1027 m, assuming that the universe is a sphere whose volume is approximately: V = 4.19 × 1081 cubic meters, the temperature radiation of the universe (cosmic microwave background radiation temperature of the universe, should be the closest the average temperature of the universe) T = 3.15k, radiation pressure P = 5 × 10-6 N / m 2, according to the law of ideal gas state equation, PV / T = constant = 6 × 1075, the value of this constant is the universe, The singular point should also equal to the constant Author: hanyongquan
Directory of Open Access Journals (Sweden)
Neal Jackson
2015-09-01
Full Text Available I review the current state of determinations of the Hubble constant, which gives the length scale of the Universe by relating the expansion velocity of objects to their distance. There are two broad categories of measurements. The first uses individual astrophysical objects which have some property that allows their intrinsic luminosity or size to be determined, or allows the determination of their distance by geometric means. The second category comprises the use of all-sky cosmic microwave background, or correlations between large samples of galaxies, to determine information about the geometry of the Universe and hence the Hubble constant, typically in a combination with other cosmological parameters. Many, but not all, object-based measurements give H_0 values of around 72–74 km s^–1 Mpc^–1, with typical errors of 2–3 km s^–1 Mpc^–1. This is in mild discrepancy with CMB-based measurements, in particular those from the Planck satellite, which give values of 67–68 km s^–1 Mpc^–1 and typical errors of 1–2 km s^–1 Mpc^–1. The size of the remaining systematics indicate that accuracy rather than precision is the remaining problem in a good determination of the Hubble constant. Whether a discrepancy exists, and whether new physics is needed to resolve it, depends on details of the systematics of the object-based methods, and also on the assumptions about other cosmological parameters and which datasets are combined in the case of the all-sky methods.
Wolf, Joseph A
2010-01-01
This book is the sixth edition of the classic Spaces of Constant Curvature, first published in 1967, with the previous (fifth) edition published in 1984. It illustrates the high degree of interplay between group theory and geometry. The reader will benefit from the very concise treatments of riemannian and pseudo-riemannian manifolds and their curvatures, of the representation theory of finite groups, and of indications of recent progress in discrete subgroups of Lie groups. Part I is a brief introduction to differentiable manifolds, covering spaces, and riemannian and pseudo-riemannian geomet
Salcedo Ortega, Manuela; Pontificia Universidad Javeriana, Cali
2013-01-01
La presencia familiar estará siempre en mi vida: Creo que esa unión va más allá de los lazos que creamos en ese primer abrir de ojos del nacimiento pues los lazos se fortalecen con el tiempo. Es que esos lazos van de la genética al riñón y puede que suene muy raro, pero esta es mi enfermedad, la primera y la constante, la que desaparece y reaparece, la heredada y la que cada vez que me saluda, deja su huella. Comenzó hace 16 años. Mis infecciones urinarias fueron el comienzo de muchas maluque...
Directory of Open Access Journals (Sweden)
Jackson Neal
2007-09-01
Full Text Available I review the current state of determinations of the Hubble constant, which gives the length scale of the Universe by relating the expansion velocity of objects to their distance. In the last 20 years, much progress has been made and estimates now range between 60 and 75 km s^-1 Mpc^-1, with most now between 70 and 75 km s^-1 Mpc^-1, a huge improvement over the factor-of-2 uncertainty which used to prevail. Further improvements which gave a generally agreed margin of error of a few percent rather than the current 10% would be vital input to much other interesting cosmology. There are several programmes which are likely to lead us to this point in the next 10 years.
Constant Proportion Portfolio Insurance
DEFF Research Database (Denmark)
Jessen, Cathrine
2014-01-01
Portfolio insurance, as practiced in 1987, consisted of trading between an underlying stock portfolio and cash, using option theory to place a floor on the value of the position, as if it included a protective put. Constant Proportion Portfolio Insurance (CPPI) is an option-free variation...... on the theme, originally proposed by Fischer Black. In CPPI, a financial institution guarantees a floor value for the “insured” portfolio and adjusts the stock/bond mix to produce a leveraged exposure to the risky assets, which depends on how far the portfolio value is above the floor. Plain-vanilla portfolio...... insurance largely died with the crash of 1987, but CPPI is still going strong. In the frictionless markets of finance theory, the issuer’s strategy to hedge its liability under the contract is clear, but in the real world with transactions costs and stochastic jump risk, the optimal strategy is less obvious...
Allegheny County Addressing Landmarks
Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains address points which represent physical address locations assigned by the Allegheny County addressing authority. Data is updated by County...
Allegheny County Address Points
Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains address points which represent physical address locations assigned by the Allegheny County addressing authority. Data is updated by County...
1995-08-01
about the distances to galaxies and thereby about the expansion rate of the Universe. A simple way to determine the distance to a remote galaxy is by measuring its redshift, calculate its velocity from the redshift and divide this by the Hubble constant, H0. For instance, the measured redshift of the parent galaxy of SN 1995K (0.478) yields a velocity of 116,000 km/sec, somewhat more than one-third of the speed of light (300,000 km/sec). From the universal expansion rate, described by the Hubble constant (H0 = 20 km/sec per million lightyears as found by some studies), this velocity would indicate a distance to the supernova and its parent galaxy of about 5,800 million lightyears. The explosion of the supernova would thus have taken place 5,800 million years ago, i.e. about 1,000 million years before the solar system was formed. However, such a simple calculation works only for relatively ``nearby'' objects, perhaps out to some hundred million lightyears. When we look much further into space, we also look far back in time and it is not excluded that the universal expansion rate, i.e. the Hubble constant, may have been different at earlier epochs. This means that unless we know the change of the Hubble constant with time, we cannot determine reliable distances of distant galaxies from their measured redshifts and velocities. At the same time, knowledge about such change or lack of the same will provide unique information about the time elapsed since the Universe began to expand (the ``Big Bang''), that is, the age of the Universe and also its ultimate fate. The Deceleration Parameter q0 Cosmologists are therefore eager to determine not only the current expansion rate (i.e., the Hubble constant, H0) but also its possible change with time (known as the deceleration parameter, q0). Although a highly accurate value of H0 has still not become available, increasing attention is now given to the observational determination of the second parameter, cf. also the Appendix at the
Multifocal, chronic osteomyelitis of unknown etiology
International Nuclear Information System (INIS)
Kozlowski, K.; Beluffi, G.; Feltham, C.; James, M.; Nespoli, L.; Tamaela, L.; Pavia Univ.; Municipal Hospital, Nelson; Medical School, Jakarta
1985-01-01
Four cases of multifocal osteomyelitis of unknown origin in childhood are reported. The variable clinical and radiographic appearances of the disease are illustrated and the diagnostic difficulties in the early stages of the disease are stressed. (orig.) [de
U.S. Environmental Protection Agency — The Reach Address Database (RAD) stores the reach address of each Water Program feature that has been linked to the underlying surface water features (streams,...
Coefficients and constants in the partial fractions of some ...
African Journals Online (AJOL)
Emumejaye and Ekeh, [3] to trigonometric inverse functions. It determines the unknown constants and coefficients in resolving rational functions containing trigonometric inverse functions in their denominator, into the sum of its partial fractions equivalent by recursive method. For each of the cases of functions considered, ...
Bayesian modeling of unknown diseases for biosurveillance.
Shen, Yanna; Cooper, Gregory F
2009-11-14
This paper investigates Bayesian modeling of unknown causes of events in the context of disease-outbreak detection. We introduce a Bayesian approach that models and detects both (1) known diseases (e.g., influenza and anthrax) by using informative prior probabilities and (2) unknown diseases (e.g., a new, highly contagious respiratory virus that has never been seen before) by using relatively non-informative prior probabilities. We report the results of simulation experiments which support that this modeling method can improve the detection of new disease outbreaks in a population. A key contribution of this paper is that it introduces a Bayesian approach for jointly modeling both known and unknown causes of events. Such modeling has broad applicability in medical informatics, where the space of known causes of outcomes of interest is seldom complete.
Protocol for counterfactually transporting an unknown qubit
Directory of Open Access Journals (Sweden)
Hatim eSalih
2016-01-01
Full Text Available Quantum teleportation circumvents the uncertainty principle using dual channels: a quantum one consisting of previously-shared entanglement, and a classical one, together allowing the disembodied transport of an unknown quantum state over distance. It has recently been shown that a classical bit can be counterfactually communicated between two parties in empty space, Alice and Bob. Here, by using our dual version of the chained quantum Zeno effect to achieve a counterfactual CNOT gate, we propose a protocol for transporting an unknown qubit counterfactually, that is without any physical particles travelling between Alice and Bob—no classical channel and no previously-shared entanglement.
Conquering the Unknown: Exploring the Options
Baker, Lynne M.
2012-01-01
There are many challenges that lie ahead for families of children with special needs. It is indeed a time for conquering the unknown and diligently exploring the options in an effort to locate, understand, and ultimately embrace the as yet undiscovered beauties of the new setting. This paper will consider some of the issues relevant for parents,…
Unknown Vocabulary Density and Reading Comprehension.
Hsueh-Chao, Marcella Hu; Nation, Paul
2000-01-01
Examines what percentage of coverage of text is needed for unassisted reading for pleasure, where learners are able to read without the interruption of looking up words. Looks at the effect of three densities of unknown vocabulary on two measures of reading comprehension, a multiple-choice test and a cued written recall test. (Author/VWL)
Ovine wet carcass syndrome of unknown aetiology
African Journals Online (AJOL)
A condition of unknown aetiology, known as 'the wet sheep carcass syndrome' has led to the loss of about ... aetiology. Introduction. Wet sheep carcasses were seen with increasing frequency at abattoirs from January 1981. ... the holding pens, and transport stress. In the high incidence area (see Figure 1), feeding systems.
Spectrophotometric determination of association constant
DEFF Research Database (Denmark)
2016-01-01
Least-squares 'Systematic Trial-and-Error Procedure' (STEP) for spectrophotometric evaluation of association constant (equilibrium constant) K and molar absorption coefficient E for a 1:1 molecular complex, A + B = C, with error analysis according to Conrow et al. (1964). An analysis of the Charg...
Staat, W.
2016-01-01
Stanley Cavell’s theory of film melodrama is used for Christian Petzold’s Phoenix, Wolfsburg, and Barbara. Key for Cavell’s understanding of classical Hollywood melodrama is his notion of the ‘unknown woman.’ Remarkably, Petzold’s more contemporary melodramas feature unknown, i.e. unacknowledged,
Melanoma of unknown origin: a case series.
LENUS (Irish Health Repository)
Kelly, J
2010-12-01
The natural history of metastatic melanoma involving lymph nodes, in the absence of a known primary site (cutaneous, ocular or mucosal) has, to date, been poorly defined; and the optimal management of this rare subtype of disease is therefore unclear. Melanomas of unknown primary site (MUP) are estimated to comprise between 3.7 and 6% of all melanomas (Anbari et al. in Cancer 79:1861-1821, 1997).
"Freud" and Bullitt: an unknown manuscript.
Solms, Mark
2006-01-01
An English translation of a previously unknown manuscript by Freud is presented. The manuscript, originally prepared in 1931 for William Bullitt's psychobiography of Woodrow Wilson, provides a general theoretical introduction to psychoanalysis. It also includes an original interpretation of Christianity that postulates a deep-going continuity between Christ identification and latent homosexuality. An editorial introduction to the translation clarifies the nature and limits of Freud's involvement with Bullitt's controversial psychobiography.
Multidimensional procurement auctions with unknown weights
DEFF Research Database (Denmark)
Greve, Thomas
This paper studies the consequences of holding a procurement auction when the principal chooses not to show its preferences. My paper extends the procurement auction model of Che (1993) to a situation where both the principal and the agents have private information. Thus, unknown parameters of bo...... gives rise to an analysis of a principal that can not fully commit to the outcome induced by the scoring rule. Therefore, my result apply to contract theory and it’s problems with imperfect commitment....
Addressing Ozone Layer Depletion
Access information on EPA's efforts to address ozone layer depletion through regulations, collaborations with stakeholders, international treaties, partnerships with the private sector, and enforcement actions under Title VI of the Clean Air Act.
Addressivity in cogenerative dialogues
Hsu, Pei-Ling
2014-03-01
Ashraf Shady's paper provides a first-hand reflection on how a foreign teacher used cogens as culturally adaptive pedagogy to address cultural misalignments with students. In this paper, Shady drew on several cogen sessions to showcase his journey of using different forms of cogens with his students. To improve the quality of cogens, one strategy he used was to adjust the number of participants in cogens. As a result, some cogens worked and others did not. During the course of reading his paper, I was impressed by his creative and flexible use of cogens and at the same time was intrigued by the question of why some cogens work and not others. In searching for an answer, I found that Mikhail Bakhtin's dialogism, especially the concept of addressivity, provides a comprehensive framework to address this question. In this commentary, I reanalyze the cogen episodes described in Shady's paper in the light of dialogism. My analysis suggests that addressivity plays an important role in mediating the success of cogens. Cogens with high addressivity function as internally persuasive discourse that allows diverse consciousnesses to coexist and so likely affords productive dialogues. The implications of addressivity in teaching and learning are further discussed.
Varying Constants, Gravitation and Cosmology.
Uzan, Jean-Philippe
2011-01-01
Fundamental constants are a cornerstone of our physical laws. Any constant varying in space and/or time would reflect the existence of an almost massless field that couples to matter. This will induce a violation of the universality of free fall. Thus, it is of utmost importance for our understanding of gravity and of the domain of validity of general relativity to test for their constancy. We detail the relations between the constants, the tests of the local position invariance and of the universality of free fall. We then review the main experimental and observational constraints that have been obtained from atomic clocks, the Oklo phenomenon, solar system observations, meteorite dating, quasar absorption spectra, stellar physics, pulsar timing, the cosmic microwave background and big bang nucleosynthesis. At each step we describe the basics of each system, its dependence with respect to the constants, the known systematic effects and the most recent constraints that have been obtained. We then describe the main theoretical frameworks in which the low-energy constants may actually be varying and we focus on the unification mechanisms and the relations between the variation of different constants. To finish, we discuss the more speculative possibility of understanding their numerical values and the apparent fine-tuning that they confront us with.
Varying Constants, Gravitation and Cosmology
Directory of Open Access Journals (Sweden)
Jean-Philippe Uzan
2011-03-01
Full Text Available Fundamental constants are a cornerstone of our physical laws. Any constant varying in space and/or time would reflect the existence of an almost massless field that couples to matter. This will induce a violation of the universality of free fall. Thus, it is of utmost importance for our understanding of gravity and of the domain of validity of general relativity to test for their constancy. We detail the relations between the constants, the tests of the local position invariance and of the universality of free fall. We then review the main experimental and observational constraints that have been obtained from atomic clocks, the Oklo phenomenon, solar system observations, meteorite dating, quasar absorption spectra, stellar physics, pulsar timing, the cosmic microwave background and big bang nucleosynthesis. At each step we describe the basics of each system, its dependence with respect to the constants, the known systematic effects and the most recent constraints that have been obtained. We then describe the main theoretical frameworks in which the low-energy constants may actually be varying and we focus on the unification mechanisms and the relations between the variation of different constants. To finish, we discuss the more speculative possibility of understanding their numerical values and the apparent fine-tuning that they confront us with.
From the Rydberg constant to the fundamental constants metrology
International Nuclear Information System (INIS)
Nez, F.
2005-06-01
This document reviews the theoretical and experimental achievements of the author since the beginning of his scientific career. This document is dedicated to the spectroscopy of hydrogen, deuterium and helium atoms. The first part is divided into 6 sub-sections: 1) the principles of hydrogen spectroscopy, 2) the measurement of the 2S-nS/nD transitions, 3) other optical frequency measurements, 4) our contribution to the determination of the Rydberg constant, 5) our current experiment on the 1S-3S transition, 6) the spectroscopy of the muonic hydrogen. Our experiments have improved the accuracy of the Rydberg Constant by a factor 25 in 15 years and we have achieved the first absolute optical frequency measurement of a transition in hydrogen. The second part is dedicated to the measurement of the fine structure constant and the last part deals with helium spectroscopy and the search for optical references in the near infrared range. (A.C.)
Constant fields and constant gradients in open ionic channels.
Chen, D P; Barcilon, V; Eisenberg, R S
1992-05-01
Ions enter cells through pores in proteins that are holes in dielectrics. The energy of interaction between ion and charge induced on the dielectric is many kT, and so the dielectric properties of channel and pore are important. We describe ionic movement by (three-dimensional) Nemst-Planck equations (including flux and net charge). Potential is described by Poisson's equation in the pore and Laplace's equation in the channel wall, allowing induced but not permanent charge. Asymptotic expansions are constructed exploiting the long narrow shape of the pore and the relatively high dielectric constant of the pore's contents. The resulting one-dimensional equations can be integrated numerically; they can be analyzed when channels are short or long (compared with the Debye length). Traditional constant field equations are derived if the induced charge is small, e.g., if the channel is short or if the total concentration gradient is zero. A constant gradient of concentration is derived if the channel is long. Plots directly comparable to experiments are given of current vs voltage, reversal potential vs. concentration, and slope conductance vs. concentration. This dielectric theory can easily be tested: its parameters can be determined by traditional constant field measurements. The dielectric theory then predicts current-voltage relations quite different from constant field, usually more linear, when gradients of total concentration are imposed. Numerical analysis shows that the interaction of ion and channel can be described by a mean potential if, but only if, the induced charge is negligible, that is to say, the electric field is spatially constant.
Metastasis to neck from unknown primary tumor
International Nuclear Information System (INIS)
Jose, B.; Bosch, A.; Caldwell, W.L.; Frias, Z.
1979-01-01
The records of 54 consecutive patients who were irradiated for metastatic disease in the neck from an unknown primary tumor were reviewed. The overall survival results are comparable to those of other reported series. Patients with high or posterior cervical lymph node involvement were irradiated with fields including the nasopharynx and oropharynx. Patients with high neck nodes had a better survival rate than those with low neck nodes. The size of the neck tumors and the local control after treatment also have prognostic significance. (Auth.)
To Know The Way To The Unknown
DEFF Research Database (Denmark)
Boysen, Mikkel Snorre Wilms
2017-01-01
, in various ways, expertise plays an important part in creative processes. However, the case studies also indicate that expertise sometimes leads to an entrenched perspective, in the sense that knowledge and experience may work as a path into the well-known rather than into the unknown. In this article......, these issues are explored with reference to different theoretical approaches to creativity and learning, including actor-network theory, the theory of blind variation and selective retention, and Csikszentmihalyi’s system model. Finally, some educational aspects and implications of this are discussed....
Infectious causes of fever of unknown origin.
McGregor, Alastair C; Moore, David A
2015-06-01
The causes of fever of unknown origin (FUO) are changing because advances in clinical practice and diagnostics have facilitated the identification of some infections. A variety of bacterial infections can cause FUO, and these can be divided into those that are easy to identify using culture and those that require serological or molecular tests for identification. A number of viral, parasitic and fungal infections can also cause prolonged fever. This article summarises the clinical features and diagnostic strategy of these infections. © Royal College of Physicians 2015. All rights reserved.
TOURISM PROMOTION FOR UNKNOWN AREAS IN ROMANIA
Directory of Open Access Journals (Sweden)
Fotache Lacramioara
2013-12-01
Full Text Available The paper is an effort to unknown areas identity affirmation, through collaborative development of advertising mix, with an emphasis on virtual platforms as admissible solution for increasing visibility. Based upon comparative effective analysis of categories of communication particularities, it is suggested a positioning strategic solution, via virtual advertising platform as unique, integrated, complex and very attractive tourism product promotion, fitted for the internal and international tourism circuit. The active promotion of the specified territorial identity will launch a brand with an impact among tourists by using marketing techniques and innovating technical means and prioritizing tourism as a principal vector of local and regional development.
Learning Read-constant Polynomials of Constant Degree modulo Composites
DEFF Research Database (Denmark)
Chattopadhyay, Arkadev; Gavaldá, Richard; Hansen, Kristoffer Arnsfelt
2011-01-01
Boolean functions that have constant degree polynomial representation over a fixed finite ring form a natural and strict subclass of the complexity class \\textACC0ACC0. They are also precisely the functions computable efficiently by programs over fixed and finite nilpotent groups. This class...... is not known to be learnable in any reasonable learning model. In this paper, we provide a deterministic polynomial time algorithm for learning Boolean functions represented by polynomials of constant degree over arbitrary finite rings from membership queries, with the additional constraint that each variable...
Generative Street Addresses from Satellite Imagery
Directory of Open Access Journals (Sweden)
İlke Demir
2018-03-01
Full Text Available We describe our automatic generative algorithm to create street addresses from satellite images by learning and labeling roads, regions, and address cells. Currently, 75% of the world’s roads lack adequate street addressing systems. Recent geocoding initiatives tend to convert pure latitude and longitude information into a memorable form for unknown areas. However, settlements are identified by streets, and such addressing schemes are not coherent with the road topology. Instead, we propose a generative address design that maps the globe in accordance with streets. Our algorithm starts with extracting roads from satellite imagery by utilizing deep learning. Then, it uniquely labels the regions, roads, and structures using some graph- and proximity-based algorithms. We also extend our addressing scheme to (i cover inaccessible areas following similar design principles; (ii be inclusive and flexible for changes on the ground; and (iii lead as a pioneer for a unified street-based global geodatabase. We present our results on an example of a developed city and multiple undeveloped cities. We also compare productivity on the basis of current ad hoc and new complete addresses. We conclude by contrasting our generative addresses to current industrial and open solutions.
Young, Ellie L.; Ashbaker, Betty Y.
2008-01-01
This article discusses ways on how to address the problem of sexual harassment in schools. Sexual harassment--simply defined as any unwanted and unwelcome sexual behavior--is a sensitive topic. Merely providing students, parents, and staff members with information about the school's sexual harassment policy is insufficient; schools must take…
Schoebel, Susan
1991-01-01
Maintains that advertising can help people become more aware of social responsibilities. Describes a successful nationwide newspaper advertising competition for college students in which ads address social issues such as literacy, drugs, teen suicide, and teen pregnancy. Notes how the ads have helped grassroots programs throughout the United…
Directory of Open Access Journals (Sweden)
Akindele, Dele Femi
2008-01-01
Full Text Available Address forms constitute an integral part of Basotho sociolinguistic etiquette. They are regarded as a kind of emotional capital that may be invested in putting others at ease. They are indicators of deference, politeness and markers of social distance. (Fasold 1990, Akindele 1990, 1991, 1993 This paper examines the address forms used by the Basotho people. It analyzes and discusses the various types and the factors determining their use. The discussion of address forms in Sesotho focuses on First Name, Title plus First Name, Title plus Last Name, Nickname, Multiple Names, and Teknonym. Drawing data from semi-literate and literate urban and rural population of Maseru district of Lesotho, it was found that the commonest form of address used by the Basotho people is title plus first name. e.g. ntate Thabo (father Thabo, 'm'e Puleng (mother Puleng, ausi Maneo (sister Maneo, abuti Mahao (brother Mahao. It is used by close relations, associates, and familiar people in both formal and informal situations.
Addressivity in Cogenerative Dialogues
Hsu, Pei-Ling
2014-01-01
Ashraf Shady's paper provides a first-hand reflection on how a foreign teacher used cogens as culturally adaptive pedagogy to address cultural misalignments with students. In this paper, Shady drew on several cogen sessions to showcase his journey of using different forms of cogens with his students. To improve the quality of cogens, one…
Energy Technology Data Exchange (ETDEWEB)
Nez, F
2005-06-15
This document reviews the theoretical and experimental achievements of the author since the beginning of his scientific career. This document is dedicated to the spectroscopy of hydrogen, deuterium and helium atoms. The first part is divided into 6 sub-sections: 1) the principles of hydrogen spectroscopy, 2) the measurement of the 2S-nS/nD transitions, 3) other optical frequency measurements, 4) our contribution to the determination of the Rydberg constant, 5) our current experiment on the 1S-3S transition, 6) the spectroscopy of the muonic hydrogen. Our experiments have improved the accuracy of the Rydberg Constant by a factor 25 in 15 years and we have achieved the first absolute optical frequency measurement of a transition in hydrogen. The second part is dedicated to the measurement of the fine structure constant and the last part deals with helium spectroscopy and the search for optical references in the near infrared range. (A.C.)
Systematics of constant roll inflation
Anguelova, Lilia; Suranyi, Peter; Wijewardhana, L. C. R.
2018-02-01
We study constant roll inflation systematically. This is a regime, in which the slow roll approximation can be violated. It has long been thought that this approximation is necessary for agreement with observations. However, recently it was understood that there can be inflationary models with a constant, and not necessarily small, rate of roll that are both stable and compatible with the observational constraint ns ≈ 1. We investigate systematically the condition for such a constant-roll regime. In the process, we find a whole new class of inflationary models, in addition to the known solutions. We show that the new models are stable under scalar perturbations. Finally, we find a part of their parameter space, in which they produce a nearly scale-invariant scalar power spectrum, as needed for observational viability.
Strain fluctuations and elastic constants
Energy Technology Data Exchange (ETDEWEB)
Parrinello, M.; Rahman, A.
1982-03-01
It is shown that the elastic strain fluctuations are a direct measure of elastic compliances in a general anisotropic medium; depending on the ensemble in which the fluctuation is measured either the isothermal or the adiabatic compliances are obtained. These fluctuations can now be calculated in a constant enthalpy and pressure, and hence, constant entropy, ensemble due to recent develpments in the molecular dynamics techniques. A calculation for a Ni single crystal under uniform uniaxial 100 tensile or compressive load is presented as an illustration of the relationships derived between various strain fluctuations and the elastic modulii. The Born stability criteria and the behavior of strain fluctuations are shown to be related.
Estimation of the false discovery proportion with unknown dependence.
Fan, Jianqing; Han, Xu
2017-09-01
Large-scale multiple testing with correlated test statistics arises frequently in many scientific research. Incorporating correlation information in approximating false discovery proportion has attracted increasing attention in recent years. When the covariance matrix of test statistics is known, Fan, Han & Gu (2012) provided an accurate approximation of False Discovery Proportion (FDP) under arbitrary dependence structure and some sparsity assumption. However, the covariance matrix is often unknown in many applications and such dependence information has to be estimated before approximating FDP. The estimation accuracy can greatly affect FDP approximation. In the current paper, we aim to theoretically study the impact of unknown dependence on the testing procedure and establish a general framework such that FDP can be well approximated. The impacts of unknown dependence on approximating FDP are in the following two major aspects: through estimating eigenvalues/eigenvectors and through estimating marginal variances. To address the challenges in these two aspects, we firstly develop general requirements on estimates of eigenvalues and eigenvectors for a good approximation of FDP. We then give conditions on the structures of covariance matrices that satisfy such requirements. Such dependence structures include banded/sparse covariance matrices and (conditional) sparse precision matrices. Within this framework, we also consider a special example to illustrate our method where data are sampled from an approximate factor model, which encompasses most practical situations. We provide a good approximation of FDP via exploiting this specific dependence structure. The results are further generalized to the situation where the multivariate normality assumption is relaxed. Our results are demonstrated by simulation studies and some real data applications.
Carcinomatous Meningitis from Unknown Primary Carcinoma
Directory of Open Access Journals (Sweden)
L. Favier
2009-10-01
Full Text Available Carcinomatous meningitis (CM occurs in 3 to 8% of cancer patients. Patients present with a focal symptom, and multifocal signs are often found following neurological examination. The gold standard for diagnosis remains the demonstration of carcinomatous cells in the cerebrospinal fluid on cytopathological examination. Despite the poor prognosis, palliative treatment could improve quality of life and, in some cases, overall survival. We report on a patient who presented with vertigo, tinnitus and left-sided hearing loss followed by progressive diffuse facial nerve paralysis. Lumbar cerebrospinal fluid confirmed the diagnosis of CM. However, no primary tumor was discovered, even after multiple invasive investigations. This is the first reported case in the English-language medical literature of CM resulting from a carcinoma of unknown primary origin.
Fever of unknown origin in returning travellers.
Korzeniewski, Krzysztof; Gaweł, Bartłomiej; Krankowska, Dagny; Wasilczuk, Katarzyna
2015-01-01
The aim of the article is to discuss issues associated with the occurrence of febrile illnesses in leisure and business travellers, with a particular emphasis on fevers of unknown origin (FUO). FUO, apart from diarrhoeas, respiratory tract infections and skin lesions, are one of the most common health problems in travellers to tropical and subtropical countries. FUO are manifestations of various diseases, typically of infectious or invasive aetiology. In one out of 3 cases, the cause of a fever in travellers returning from the hot climate zone is malaria, and therefore diagnostic tests should first aim at ruling out this specific disease entity. Other illnesses with persistent fever include dengue, enteric fever, viral hepatitis A, bacterial diarrhoeas and rickettsioses. Fever may also occur in travellers suffering from diseases of non-tropical origin, e.g. cosmopolitan respiratory tract or urinary tract infections, also, fever may coexist with other illnesses or injuries (skin rashes, bites, burns).
Information gain when measuring an unknown qubit
Björk, Gunnar
2018-01-01
In quantum information the fundamental information-containing system is the qubit. A measurement of a single qubit can at most yield one classical bit. However, a dichotomous measurement of an unknown qubit will yield much less information about the qubit state. We use Bayesian inference to compute how much information one progressively gets by making sucessive, individual measurements on an ensemble of identically prepared qubits. Perhaps surprisingly, even if the measurements are arranged so that each measurement yields one classical bit, that is, the two possible measurement outcomes are a priori equiprobable, it takes almost a handful of measurements before one has gained one bit of information about the gradually concentrated qubit probability density. We also show that by following a strategy that reaps the maximum information per measurement, we are led to a mutually unbiased basis as our measurement bases. This is a pleasing, although not entirely surprising, result.
Fukushima to Jaitapur: battling fear of unknown
International Nuclear Information System (INIS)
Ghate, Tushar P.; Takwale, M.G.; Dhole, Sanjay
2011-01-01
After-Fukushima incident, various concerns were raised by public and media about the safety of nuclear installations operating all around the world. All nuclear related eventualities of the past were meshed with the present, adding disproportionate factors, unrealistic conclusions were framed based mostly on notions. Fear of unknown radiation syndrome has played up on the minds of common man. India, on a verge of entering path-breaking nuclear energy arena, obviously could not be isolated from such concerns. Such issues were discussed with ongoing protests at Jaitapur and Kudankulam. This paper discusses various concerns expressed after Fukushima incident, overview on proposed Jaitapur nuclear power plant and justifications to the raised concerns. (author)
Non-constant retardation coefficient
International Nuclear Information System (INIS)
Wang Zhiming; Gu Zhijie; Yang Yue'e; Li Shushen
2004-12-01
Retardation coefficient is one of the important parameters used in transport models describing radionuclide migration in geological media and usually regarded as a constant in the models. The objectives of the work are to understand: (1) Whether the retardation coefficient, R d , is a constant? (2) How much effect is R d on calculated consequence if R d is not constant? (3) Is the retardation coefficient derived from distribution coefficient, k d , according to conventional equation suitable for safety assessment? The objectives are achieved through test and analysis of the test results on radionuclide migration in unsaturated loess. It can be seen from the results that retardation coefficient, R d , of 85 Sr is not constant and increases with water content, θ, under unsaturated condition. R d , of 85 Sr derived from k d according to conventional equation can not be used for safety assessment. R d , used for safety assessment should be directly measured, rather than derived from k d . It is shown from calculation that the effect of R d on calculated consequence is very considerable. (authors)
Universal relation between spectroscopic constants
Indian Academy of Sciences (India)
(3) The author has used eq. (6) of his paper to calculate De. This relation leads to a large deviation from the correct value depending upon the extent to which experimental values are known. Guided by this fact, in our work, we used experimentally observed De values to derive the relation between spectroscopic constants.
Stabilized power constant alimentation; Alimentation regulee a puissance constante
Energy Technology Data Exchange (ETDEWEB)
Roussel, L. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1968-06-01
The study and realization of a stabilized power alimentation variable from 5 to 100 watts are described. In order to realize a constant power drift of Lithium compensated diodes, we have searched a 1 per cent precision of regulation and a response time minus than 1 sec. Recent components like Hall multiplicator and integrated amplifiers give this possibility and it is easy to use permutable circuits. (author) [French] On decrit l'etude et la realisation d'une alimentation a puissance constante reglable dans une gamme de 5 a 100 watts. Prevue pour le drift a puissance constante des diodes compensees au lithium, l'etude a ete menee en vue d'obtenir une precision de regulation de 1 pour cent et un temps de reponse inferieur a la seconde. Des systemes recents tels que multiplicateurs a effet Hall et circuits integres ont permis d'atteindre ce but tout en facilitant l'emploi de modules interchangeables. (auteur)
Constant-bandwidth constant-temperature hot-wire anemometer.
Ligeza, P
2007-07-01
A constant-temperature anemometer (CTA) enables the measurement of fast-changing velocity fluctuations. In the classical solution of CTA, the transmission band is a function of flow velocity. This is a minor drawback when the mean flow velocity does not significantly change, though it might lead to dynamic errors when flow velocity varies over a considerable range. A modification is outlined, whereby an adaptive controller is incorporated in the CTA system such that the anemometer's transmission band remains constant in the function of flow velocity. For that purpose, a second feedback loop is provided, and the output signal from the anemometer will regulate the controller's parameters such that the transmission bandwidth remains constant. The mathematical model of a CTA that has been developed and model testing data allow a through evaluation of the proposed solution. A modified anemometer can be used in measurements of high-frequency variable flows in a wide range of velocities. The proposed modification allows the minimization of dynamic measurement errors.
Unknown Risks: Parental Hesitation about Vaccination.
Blaisdell, Laura L; Gutheil, Caitlin; Hootsmans, Norbert A M; Han, Paul K J
2016-05-01
This qualitative study of a select sample of vaccine-hesitant parents (VHPs) explores perceived and constructed personal judgments about the risks and uncertainties associated with vaccines and vaccine-preventable diseases (VPDs) and how these subjective risk judgments influence parents' decisions about childhood vaccination. The study employed semistructured focus group interviews with 42 VHPs to elicit parents' perceptions and thought processes regarding the risks associated with vaccination and nonvaccination, the sources of these perceptions, and their approach to decision making about vaccination for their children. VHPs engage in various reasoning processes and tend to perceive risks of vaccination as greater than the risks of VPDs. At the same time, VHPs engage in other reasoning processes that lead them to perceive ambiguity in information about the harms of vaccination-citing concerns about the missing, conflicting, changing, or otherwise unreliable nature of information. VHPs' refusal of vaccination may reflect their aversion to both the risk and ambiguity they perceive to be associated with vaccination. Mitigating this vaccine hesitancy likely requires reconstructing the risks and ambiguities associated with vaccination-a challenging task that requires providing parents with meaningful evidence-based information on the known risks of vaccination versus VPDs and explicitly acknowledging the risks that remain truly unknown. © The Author(s) 2015.
Cosmological Constant and Local Gravity
Bernabeu, Jose; Mavromatos, Nick E
2010-01-01
We discuss the linearization of Einstein equations in the presence of a cosmological constant, by expanding the solution for the metric around a flat Minkowski space-time. We demonstrate that one can find consistent solutions to the linearized set of equations for the metric perturbations, in the Lorentz gauge, which are not spherically symmetric, but they rather exhibit a cylindrical symmetry. We find that the components of the gravitational field satisfying the appropriate Poisson equations have the property of ensuring that a scalar potential can be constructed, in which both contributions, from ordinary matter and $\\Lambda > 0$, are attractive. In addition, there is a novel tensor potential, induced by the pressure density, in which the effect of the cosmological constant is repulsive. We also linearize the Schwarzschild-de Sitter exact solution of Einstein's equations (due to a generalization of Birkhoff's theorem) in the domain between the two horizons. We manage to transform it first to a gauge in whic...
Evolution of the solar constant
International Nuclear Information System (INIS)
Newman, M.J.
1978-01-01
The ultimate source of the energy utilized by life on Earth is the Sun, and the behavior of the Sun determines to a large extent the conditions under which life originated and continues to thrive. What can be said about the history of the Sun. Has the solar constant, the rate at which energy is received by the Earth from the Sun per unit area per unit time, been constant at its present level since Archean times. Three mechanisms by which it has been suggested that the solar energy output can vary with time are discussed, characterized by long (approx. 10 9 years), intermediate (approx. 10 8 years), and short (approx. years to decades) time scales
International Nuclear Information System (INIS)
Jones, L.H.; Kennedy, C.; Ekberg, S.
1978-01-01
The infrared spectra of the 12 C, 13 C, and 14 C isotopic species of CF 4 have been observed at a resolution of 0.06 cm -1 . In addition to the fundamentals ν 3 and ν 4 a number of combination bands have been observed. Using these results, combined with Raman data in the literature, we have calculated the quadratic valence force field, in terms of force constants as well as compliance constants, with considerably better precision than previously obtained. Interaction displacement coordinates have been calculated and show that stretching one CF bond leads, for minimum energy near equilibrium, to opening up of the angles between the other three bonds as well as to their contraction
Recursive confidence band construction for an unknown distribution function.
Kiatsupaibul, Seksan; Hayter, Anthony J
2015-01-01
Given a sample X1,...,Xn of independent observations from an unknown continuous distribution function F, the problem of constructing a confidence band for F is considered, which is a fundamental problem in statistical inference. This confidence band provides simultaneous inferences on all quantiles and also on all of the cumulative probabilities of the distribution, and so they are among the most important inference procedures that address the issue of multiplicity. A fully nonparametric approach is taken where no assumptions are made about the distribution function F. Historical approaches to this problem, such as Kolmogorov's famous () procedure, represent some of the earliest inference methodologies that address the issue of multiplicity. This is because a confidence band at a given confidence level 1-α allows inferences on all of the quantiles of the distribution, and also on all of the cumulative probabilities, at that specified confidence level. In this paper it is shown how recursive methodologies can be employed to construct both one-sided and two-sided confidence bands of various types. The first approach operates by putting bounds on the cumulative probabilities at the data points, and a recursive integration approach is described. The second approach operates by providing bounds on certain specified quantiles of the distribution, and its implementation using recursive summations of multinomial probabilities is described. These recursive methodologies are illustrated with examples, and R code is available for their implementation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Photodissociation constant of NO2
International Nuclear Information System (INIS)
Nootebos, M.A.; Bange, P.
1992-01-01
The velocity of the dissociation of NO 2 into ozone and NO mainly depends on the ultraviolet sunlight quantity, and with that the cloudiness. A correct value for this reaction constant is important for the accurate modelling of O 3 - and NO 2 -concentrations in plumes of electric power plants, in particular in the case of determination of the amount of photochemical summer smog. An advanced signal processing method (deconvolution, correlation) was applied on the measurements. The measurements were carried out from aeroplanes
Searching for Kaprekar's constants: algorithms and results
Walden, Byron L.
2005-01-01
We examine some new results on Kaprekar's constants, specifically establishing the unique 7-digit (in base 4) and 9-digit (in base 5) Kaprekar's constants and showing that there are no 15-, 21-, 27-, or 33-digit Kaprekar's constants.
A Polynomial Optimization Approach to Constant Rebalanced Portfolio Selection
Takano, Y.; Sotirov, R.
2010-01-01
We address the multi-period portfolio optimization problem with the constant rebalancing strategy. This problem is formulated as a polynomial optimization problem (POP) by using a mean-variance criterion. In order to solve the POPs of high degree, we develop a cutting-plane algorithm based on
The Constant Comparative Analysis Method Outside of Grounded Theory
Fram, Sheila M.
2013-01-01
This commentary addresses the gap in the literature regarding discussion of the legitimate use of Constant Comparative Analysis Method (CCA) outside of Grounded Theory. The purpose is to show the strength of using CCA to maintain the emic perspective and how theoretical frameworks can maintain the etic perspective throughout the analysis. My…
Effects of memory colour on colour constancy for unknown coloured objects
Granzier, Jeroen J M; Gegenfurtner, Karl R
2012-01-01
The perception of an object's colour remains constant despite large variations in the chromaticity of the illumination—colour constancy. Hering suggested that memory colours, the typical colours of objects, could help in estimating the illuminant's colour and therefore be an important factor in establishing colour constancy. Here we test whether the presence of objects with diagnostical colours (fruits, vegetables, etc) within a scene influence colour constancy for unknown coloured objects in...
Chu, Zhaobi; Zhang, Rui; Chen, Bo; Li, Hua
2017-07-01
An algorithm to estimate symmetrical components, orthogonal components and amplitudes of each sinusoidal component in three-phase power system signal under unknown frequencies and unknown biases is presented. The algorithm consists of a signal transformation, a biased adaptive orthogonal decomposition (BAOD) and a symmetrical component estimation. The BAOD can be regarded as a combination of a low pass filter and a number of three-phase frequency estimators in parallel. The symmetrical component estimation employs addition and multiplication rather than operations of trigonometry, division and phase shift. The decomposition property and the convergence property were investigated by Lyapunov theorem, integral manifold of slow adaptation and average method. Two design parameters, bandwidth parameter and frequency adaptive gains, give different effects on the convergence property of frequency adaptation and amplitude estimation independently. Simulation results demonstrate the performance of the method.
Low power constant fraction discriminator
International Nuclear Information System (INIS)
Krishnan, Shanti; Raut, S.M.; Mukhopadhyay, P.K.
2001-01-01
This paper describes the design of a low power ultrafast constant fraction discriminator, which significantly reduces the power consumption. A conventional fast discriminator consumes about 1250 MW of power whereas this low power version consumes about 440 MW. In a multi detector system, where the number of discriminators is very large, reduction of power is of utmost importance. This low power discriminator is being designed for GRACE (Gamma Ray Atmospheric Cerenkov Experiments) telescope where 1000 channels of discriminators are required. A novel method of decreasing power consumption has been described. (author)
Can coupling constants be related
International Nuclear Information System (INIS)
Nandi, Satyanarayan; Ng, Wing-Chiu.
1978-06-01
We analyze the conditions under which several coupling constants in field theory can be related to each other. When the relation is independent of the renormalization point, the relation between any g and g' must satisfy a differential equation as follows from the renormalization group equations. Using this differential equation, we investigate the criteria for the feasibility of a power-series relation for various theories, especially the Weinberg-Salam type (including Higgs bosons) with an arbitrary number of quark and lepton flavors. (orig./WL) [de
Measurement of Newton's gravitational constant
International Nuclear Information System (INIS)
Schlamminger, St.; Holzschuh, E.; Kuendig, W.; Nolting, F.; Pixley, R. E.; Schurr, J.; Straumann, U.
2006-01-01
A precision measurement of the gravitational constant G has been made using a beam balance. Special attention has been given to determining the calibration, the effect of a possible nonlinearity of the balance and the zero-point variation of the balance. The equipment, the measurements, and the analysis are described in detail. The value obtained for G is 6.674 252(109)(54)x10 -11 m 3 kg -1 s -2 . The relative statistical and systematic uncertainties of this result are 16.3x10 -6 and 8.1x10 -6 , respectively
Exact constants in approximation theory
Korneichuk, N
1991-01-01
This book is intended as a self-contained introduction for non-specialists, or as a reference work for experts, to the particular area of approximation theory that is concerned with exact constants. The results apply mainly to extremal problems in approximation theory, which in turn are closely related to numerical analysis and optimization. The book encompasses a wide range of questions and problems: best approximation by polynomials and splines; linear approximation methods, such as spline-approximation; optimal reconstruction of functions and linear functionals. Many of the results are base
Counting addressing method: Command addressable element and extinguishing module
Directory of Open Access Journals (Sweden)
Ristić Jovan D.
2009-01-01
Full Text Available The specific requirements that appear in addressable fire detection and alarm systems and the shortcomings of the existing addressing methods were discussed. A new method of addressing of detectors was proposed. The basic principles of addressing and responding of a called element are stated. Extinguishing module is specific subsystem in classic fire detection and alarm systems. Appearing of addressable fire detection and alarm systems didn't caused essential change in the concept of extinguishing module because of long calling period of such systems. Addressable fire security system based on counting addressing method reaches high calling rates and enables integrating of the extinguishing module in addressable system. Solutions for command addressable element and integrated extinguishing module are given in this paper. The counting addressing method was developed for specific requirements in fire detection and alarm systems, yet its speed and reliability justifies its use in the acquisition of data on slowly variable parameters under industrial conditions. .
The fundamental constants a mystery of physics
Fritzsch, Harald
2009-01-01
The speed of light, the fine structure constant, and Newton's constant of gravity — these are just three among the many physical constants that define our picture of the world. Where do they come from? Are they constant in time and across space? In this book, physicist and author Harald Fritzsch invites the reader to explore the mystery of the fundamental constants of physics in the company of Isaac Newton, Albert Einstein, and a modern-day physicist
Omnidirectional antenna having constant phase
Energy Technology Data Exchange (ETDEWEB)
Sena, Matthew
2017-04-04
Various technologies presented herein relate to constructing and/or operating an antenna having an omnidirectional electrical field of constant phase. The antenna comprises an upper plate made up of multiple conductive rings, a lower ground-plane plate, a plurality of grounding posts, a conical feed, and a radio frequency (RF) feed connector. The upper plate has a multi-ring configuration comprising a large outer ring and several smaller rings of equal size located within the outer ring. The large outer ring and the four smaller rings have the same cross-section. The grounding posts ground the upper plate to the lower plate while maintaining a required spacing/parallelism therebetween.
Constant Proportion Debt Obligations (CPDOs)
DEFF Research Database (Denmark)
Cont, Rama; Jessen, Cathrine
2012-01-01
be made arbitrarily small—and thus the credit rating arbitrarily high—by increasing leverage, but the ratings obtained strongly depend on assumptions on the credit environment (high spread or low spread). More importantly, CPDO loss distributions are found to exhibit a wide range of tail risk measures......Constant Proportion Debt Obligations (CPDOs) are structured credit derivatives that generate high coupon payments by dynamically leveraging a position in an underlying portfolio of investment-grade index default swaps. CPDO coupons and principal notes received high initial credit ratings from...... the major rating agencies, based on complex models for the joint transition of ratings and spreads for all names in the underlying portfolio. We propose a parsimonious model for analysing the performance of CPDO strategies using a top-down approach that captures the essential risk factors of the CPDO. Our...
Content-Based Multimedia Retrieval in the Presence of Unknown User Preferences
DEFF Research Database (Denmark)
Beecks, Christian; Assent, Ira; Seidl, Thomas
2011-01-01
Content-based multimedia retrieval requires an appropriate similarity model which reflects user preferences. When these preferences are unknown or when the structure of the data collection is unclear, retrieving the most preferable objects the user has in mind is challenging, as the notion...... address the problem of content-based multimedia retrieval in the presence of unknown user preferences. Our idea consists in performing content-based retrieval by considering all possibilities in a family of similarity models simultaneously. To this end, we propose a novel content-based retrieval approach...
Arrhenius Rate: constant volume burn
Energy Technology Data Exchange (ETDEWEB)
Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2017-12-06
A constant volume burn occurs for an idealized initial state in which a large volume of reactants at rest is suddenly raised to a high temperature and begins to burn. Due to the uniform spatial state, there is no fluid motion and no heat conduction. This reduces the time evolu tion to an ODE for the reaction progress variable. With an Arrhenius reaction rate, two characteristics of thermal ignition are illustrated: induction time and thermal runaway. The Frank-Kamenetskii approximation then leads to a simple expression for the adiabatic induction time. For a first order reaction, the analytic solution is derived and used to illustrate the effect of varying the activation temperature; in particular, on the induction time. In general, the ODE can be solved numerically. This is used to illustrate the effect of varying the reaction order. We note that for a first order reaction, the time evolution of the reaction progress variable has an exponential tail. In contrast, for a reaction order less than one, the reaction completes in a nite time. The reaction order also affects the induction time.
Ben-Ayed, Rayda; Sans-Grout, Cinderella; Moreau, Fabienne; Grati-Kamoun, Naziha; Rebai, Ahmed
2014-06-01
We used eight informative microsatellite markers for fingerprinting and evaluation of genetic similarity among 15 Tunisian olive (Olea europaea L.) cultivars and two feral unknown trees named Soulela 1 and Soulela 2. Thirty-one alleles were revealed, and the number of alleles per SSR varied from 2 (UDO12) to 6 (GAPU71A). Cluster analysis grouped cultivars into three main clusters. The two unknown varieties could not be reliably classified into any of these cultivar groups. SSR analysis indicated the presence of three erroneous denominations of cultivars. We resolved two synonymy cases (Zalmati and Chemlali; Rkhami and Chetoui) and one case of homonymy (Chemlali Tataouine). Genetic analyses of DNA extracted from leaves, oils, and embryos of the two unknown cultivars and the two major Tunisian olive cultivars (Chemlali and Chetoui) were also studied. We conclude that the reliable identification of these two feral cultivars needs to be addressed by a larger set of markers.
ESR melting under constant voltage conditions
Energy Technology Data Exchange (ETDEWEB)
Schlienger, M.E.
1997-02-01
Typical industrial ESR melting practice includes operation at a constant current. This constant current operation is achieved through the use of a power supply whose output provides this constant current characteristic. Analysis of this melting mode indicates that the ESR process under conditions of constant current is inherently unstable. Analysis also indicates that ESR melting under the condition of a constant applied voltage yields a process which is inherently stable. This paper reviews the process stability arguments for both constant current and constant voltage operation. Explanations are given as to why there is a difference between the two modes of operation. Finally, constant voltage process considerations such as melt rate control, response to electrode anomalies and impact on solidification will be discussed.
Lepton decay constants of light mesons
International Nuclear Information System (INIS)
Simonov, Yu. A.
2016-01-01
A theory of lepton decay constants based on the path-integral formalism is given for chiral and vector mesons. Decay constants of the pseudoscalar and vector mesons are calculated and compared to other existing results.
Capacitive Cells for Dielectric Constant Measurement
Aguilar, Horacio Munguía; Maldonado, Rigoberto Franco
2015-01-01
A simple capacitive cell for dielectric constant measurement in liquids is presented. As an illustrative application, the cell is used for measuring the degradation of overheated edible oil through the evaluation of their dielectric constant.
Berryman, James G; Nakagawa, Seiji
2010-02-01
Poroelastic analysis has traditionally focused on the relationship between dry and drained constants, which are assumed known, and the saturated or undrained constants, which are assumed unknown. However, there are many applications in this field of study for which the main measurements can only be made on the saturated/undrained system, and then it is uncertain what the effects of the fluids were on the system, since the drained constants remain a mystery. The work presented here shows how to deduce drained constants from undrained constants for anisotropic systems having symmetries ranging from isotropic to orthotropic. Laboratory ultrasound data are then inverted for the drained constants in three granular packings: one of glass beads, and two others for distinct types of more or less angular sand grain packings. Experiments were performed under uniaxial stress, which resulted in hexagonal (transversely isotropic) symmetry of the poroelastic response. One important conclusion from the general analysis is that the drained constants are uniquely related to the undrained constants, assuming that porosity, grain bulk modulus, and pore fluid bulk modulus are already known. Since the resulting system of equations for all the drained constants is linear, measurement error in undrained constants also propagates linearly into the computed drained constants.
Energy Technology Data Exchange (ETDEWEB)
Berryman, J.G.; Nakagawa, S.
2009-11-20
Poroelastic analysis has traditionally focused on the relationship between dry or drained constants which are assumed known and the saturated or undrained constants which are assumed unknown. However, there are many applications in this field of study for which the main measurements can only be made on the saturated/undrained system, and then it is uncertain what the eects of the uids were on the system, since the drained constants remain a mystery. The work presented here shows how to deduce drained constants from undrained constants for anisotropic systems having symmetries ranging from isotropic to orthotropic. Laboratory ultrasound data are then inverted for the drained constants in three granular packings: one of glass beads, and two others for distinct types of more or less angular sand grain packings. Experiments were performed under uniaxial stress, which resulted in hexagonal (transversely isotropic) symmetry of the poroelastic response. One important conclusion from the general analysis is that the drained constants are uniquely related to the undrained constants, assuming that porosity, grain bulk modulus, and pore uid bulk modulus are already known. Since the resulting system of equations for all the drained constants is linear, measurement error in undrained constants also propagates linearly into the computed drained constants.
Anderegg, G
2013-01-01
Critical Survey of Stability Constants of EDTA Complexes focuses on the computations, values, and characteristics of stability constants. The book emphasizes that for a critical discussion of experimentally determined stability constants, it is important to consider the precision of the values that manifests the self-consistency of the constant, taking into consideration the random errors. The publication reviews the stability constants of metal complexes. The numerical calculations affirm the reactions and transformations of metal ions when exposed to varying conditions. The text also present
Surprises in numerical expressions of physical constants
Amir, Ariel; Lemeshko, Mikhail; Tokieda, Tadashi
2016-01-01
In science, as in life, `surprises' can be adequately appreciated only in the presence of a null model, what we expect a priori. In physics, theories sometimes express the values of dimensionless physical constants as combinations of mathematical constants like pi or e. The inverse problem also arises, whereby the measured value of a physical constant admits a `surprisingly' simple approximation in terms of well-known mathematical constants. Can we estimate the probability for this to be a me...
Magnetically modified biocells in constant magnetic field
International Nuclear Information System (INIS)
Abramov, E.G.; Panina, L.K.; Kolikov, V.A.; Bogomolova, E.V.; Snetov, V.N.; Cherepkova, I.A.; Kiselev, A.A.
2017-01-01
Paper addresses the inverse problem in determining the area, where the external constant magnetic field captures the biological cells modified by the magnetic nanoparticles. Zero velocity isolines, in area where the modified cells are captured by the magnetic field were determined by numerical method for two locations of the magnet. The problem was solved taking into account the gravitational field, magnetic induction, density of medium, concentration and size of cells, and size and magnetization of nanoparticles attached to the cell. Increase in the number of the nanoparticles attached to the cell and decrease in the cell’ size, enlarges the area, where the modified cells are captured and concentrated by the magnet. Solution is confirmed by the visible pattern formation of the modified cells Saccharomyces cerevisiae. - Highlights: • The inverse problem was solved for finding zero velocity isolines of magnetically modified biological cells. • Solution of the inverse problem depends on the size of cells and the number of nanoparticles attached to the single cell. • The experimental data are in agreement with theoretical solution.
Magnetically modified biocells in constant magnetic field
Energy Technology Data Exchange (ETDEWEB)
Abramov, E.G.; Panina, L.K. [Saint Petersburg State University, St. Petersburg (Russian Federation); Kolikov, V.A., E-mail: kolikov1@yandex.ru [Institute for Electrophysics and Electric Power of the RAS, St. Petersburg (Russian Federation); Bogomolova, E.V. [Botanical Institute of the RAS after V.L.Komarov, St. Petersburg (Russian Federation); Snetov, V.N. [Institute for Electrophysics and Electric Power of the RAS, St. Petersburg (Russian Federation); Cherepkova, I.A. [Saint Petersburg State Institute of Technology, St. Petersburg (Russian Federation); Kiselev, A.A. [Institute for Electrophysics and Electric Power of the RAS, St. Petersburg (Russian Federation)
2017-02-01
Paper addresses the inverse problem in determining the area, where the external constant magnetic field captures the biological cells modified by the magnetic nanoparticles. Zero velocity isolines, in area where the modified cells are captured by the magnetic field were determined by numerical method for two locations of the magnet. The problem was solved taking into account the gravitational field, magnetic induction, density of medium, concentration and size of cells, and size and magnetization of nanoparticles attached to the cell. Increase in the number of the nanoparticles attached to the cell and decrease in the cell’ size, enlarges the area, where the modified cells are captured and concentrated by the magnet. Solution is confirmed by the visible pattern formation of the modified cells Saccharomyces cerevisiae. - Highlights: • The inverse problem was solved for finding zero velocity isolines of magnetically modified biological cells. • Solution of the inverse problem depends on the size of cells and the number of nanoparticles attached to the single cell. • The experimental data are in agreement with theoretical solution.
Searching for Kaprekar's constants: algorithms and results
Directory of Open Access Journals (Sweden)
Byron L. Walden
2005-01-01
Full Text Available We examine some new results on Kaprekar's constants, specifically establishing the unique 7-digit (in base 4 and 9-digit (in base 5 Kaprekar's constants and showing that there are no 15-, 21-, 27-, or 33-digit Kaprekar's constants.
Generalized Euler constants for arithmetical progressions
Dilcher, Karl
1992-07-01
The work of Lehmer and Briggs on Euler constants in arithmetical progressions is extended to the generalized Euler constants that arise in the Laurent expansion of ζ(s) about s = 1 . The results are applied to the summation of several classes of slowly converging series. A table of the constants is provided.
Determination of the origin of unknown irradiated nuclear fuel.
Nicolaou, G
2006-01-01
An isotopic fingerprinting method is presented to determine the origin of unknown nuclear material with forensic importance. Spent nuclear fuel of known origin has been considered as the 'unknown' nuclear material in order to demonstrate the method and verify its prediction capabilities. The method compares, using factor analysis, the measured U, Pu isotopic compositions of the 'unknown' material with U, Pu isotopic compositions simulating well known spent fuels from a range of commercial nuclear power stations. Then, the 'unknown' fuel has the same origin as the commercial fuel with which it exhibits the highest similarity in U, Pu compositions.
Determination of the origin of unknown irradiated nuclear fuel
International Nuclear Information System (INIS)
Nicolaou, G.
2006-01-01
An isotopic fingerprinting method is presented to determine the origin of unknown nuclear material with forensic importance. Spent nuclear fuel of known origin has been considered as the 'unknown' nuclear material in order to demonstrate the method and verify its prediction capabilities. The method compares, using factor analysis, the measured U, Pu isotopic compositions of the 'unknown' material with U, Pu isotopic compositions simulating well known spent fuels from a range of commercial nuclear power stations. Then, the 'unknown' fuel has the same origin as the commercial fuel with which it exhibits the highest similarity in U, Pu compositions
Small cosmological constant from the QCD trace anomaly?
International Nuclear Information System (INIS)
Schuetzhold, Ralf
2002-01-01
According to recent astrophysical observations the large scale mean pressure of our present Universe is negative suggesting a positive cosmological constant-like term. The issue of whether nonperturbative effects of self-interacting quantum fields in curved space-times may yield a significant contribution is addressed. Focusing on the trace anomaly of quantum chromodynamics, a preliminary estimate of the expected order of magnitude yields a remarkable coincidence with the empirical data, indicating the potential relevance of this effect
Adaptive vison aided integrated navigation for dynamic unknown enviroments
Nematallah, Heba
In this research, a novel method for visual odometry (VO) and the integration with multi-sensors navigation systems for vehicular platforms is proposed. The proposed method partitions the field of single camera view into regions of interests where each region likely contains different types of visual features. By applying computer vision processing techniques, ambiguous pose estimation is calculated up to a scale factor. The proposed method uses aiding measurements from vehicle's odometer to adaptively resolve the scale factor ambiguity problem in monocular camera systems. Unlike some state-of-art approaches, this work does not depend on offline pre-processing or predefined landmarks or visual maps. In addition, this work addresses unknown uncontrolled environments where moving objects likely exist. Innovative odometer-aided Local Bundle Adjustment (LBA) along with a fuzzy C-mean clustering mechanism is proposed to reject outliers corresponding to moving objects. A Gaussian Mixture approach is also applied to detect visual background regions during stationary periods which enables further rejection of moving objects. Finally, an empirical scoring method is applied to calculate a matching score of the different visual features and to use this score in a Kalman filter as measurement covariance noise to integrate VOestimated pose changes within a larger multi-sensors integrated navigation system. Experimental work was performed with a physical vehicular platform equipped by MEMS inertial sensors, GPS, speed measurements and GPS-enabled camera. The experimental work includes three testing vehicular trajectories in downtown Toronto and the surrounding areas. The experimental work showed significant navigation improvements during long GPS outages where only VO is fused with inertial sensors and the vehicle's speed measurements.
RBF neural network based H∞ synchronization for unknown chaotic ...
Indian Academy of Sciences (India)
Radial Basis Function Neural Network H∞ synchronization (RBFNNHS) strategy, for unknown chaotic systems in ... lation, the RBFNNHS controller and the learning laws are presented to reduce the effect of disturbance to an ... unknown chaotic systems; linear matrix inequality (LMI); learning law. 1. Introduction. Since the ...
Port virtual addressing for PC
International Nuclear Information System (INIS)
Bolanos, L.; Arista, E.; Osorio Deliz, J.F.
1997-01-01
Instruments for nuclear signal measurements based on add-on card for a personal computer (PC) are designed often. Then one faces the problem of the addressing of data input/output devices which show an integration level or intelligence that makes the use of several port address indispensable, and these are limited in the PC. The virtual addressing offers the advantage of the occupation of few addresses to accede to many of these devices. The principles of this technique and the appliances of a solution in radiometric in a radiometric card based on programmed logic are discussed in this paper
Reclaiming unused IPv4 addresses
IT Department
2016-01-01
As many people might know, the number of IPv4 addresses is limited and almost all have been allocated (see here and here for more information). Although CERN has been allocated some 340,000 addresses, the way these are allocated across the site is not as efficient as we would like. As we face an increasing demand for IPv4 addresses with the growth in virtual machines, the IT Department’s Communication Systems Group will be reorganising address allocation during 2016 to make more efficient use of the IPv4 address ranges that have been allocated to CERN. We aim, wherever possible, to avoid giving out fixed IP addresses, and have all devices connected to the campus network obtain an address dynamically each time they connect. As a first stage, starting in February, IP addresses that have not been used for more than 9 months will be reclaimed. No information about the devices concerned will be deleted from LANDB, but a new IP address will have to be requested if they are ever reconnected to t...
The importance of being (a) constant
International Nuclear Information System (INIS)
Levy-Leblond, J.-M.
1979-01-01
The author intends to show how the epistemological status of the physical constants bears witness to the development of physical science in general. He classifies the various physical constants into three types, properties of particular physical objects, characteristics of classes of physical phenomena and universal constants. He discusses the phenomena of fundamental constants experiencing a change in their type, at length on the example of two important constants, c and G. He considers Planck's constant and discusses the conceptual role of universal constants in general, as well as some aspects of quantum mechanics which appear in a new light from the proposed point of view. The existence is shown of hidden universal constants, forgotten ones in the realm of classical physics, as well as overlooked ones in modern physics. The velocity of light is studied as an example of general considerations on universal constants, and as a way to approach some epistemological problems of special relativity. Newton's gravitational constant is studied in connection with the interpretation of general relativity. (Auth./C.F.)
Wang, Xu; Saberi, Ali; Stoorvogel, Antonie Arij; Grip, H°avard Fjær; Yang, Tao
2014-01-01
This paper studies the synchronization problem for a network of identical discrete-time agents with unknown uniform constant communication delay. When the agents are non-introspective, the problem is solvable via a decentralized low-gain-based synchronization controller if the delay satisfies the
Massa, Enrico; Nicolaus, Arnold
2011-04-01
the mass-energy-frequency equivalence. Another effort is to monitor the stability of the Pt-Ir prototype: the technologies described in the present issue can be refined and finalized to calculate the mass variation of 1 kg 28Si spheres by monitoring the surface evolution without weighing them on a balance. The last activity is the determination of the mass of a 28Si sphere by electrical measurements using a watt balance and without any reference to the Pt-Ir prototype. In this framework, it will be necessary to demonstrate the mutual consistency and the stability of both the electrical and crystal mise en pratique of a kilogram definition based on a conventional value of the Planck constant. A related issue is to develop suitable procedures and protocols to disseminate the unit of mass from the new realizations. Since the molar Planck constant is well known via the measurement of the Rydberg constant, the accurate measurement of NA also provides an accurate and independent determination of the Planck constant, h. A comparison of the values of the Planck constant obtained via the watt-balance experiment and the NA determination tests quantum mechanics. In fact, the watt-balance value of h depends on solid state physics through the theories of Josephson and quantum Hall effects, whereas the value of h derived from NA depends on atomic physics through the energy level differences in hydrogen and deuterium, whose associated transition frequencies yield information on the Rydberg constant. Grateful thanks are addressed to H-J Pohl for his outstanding project management in Russia, to A K Kaliteevski and his colleagues of the Central Design Bureau of Machine Building and the Institute of Chemistry of High-Purity Substances for their dedication and the punctual delivery of the enriched material, to H Riemann and his staff of the Institut für Kristallzüchtung for the crystal growth, to our directors for their advice and financial support, and to our colleagues for their
Stability constants of scandium complexes, 1
International Nuclear Information System (INIS)
Itoh, Hisako; Itoh, Naomi; Suzuki, Yasuo
1984-01-01
The stability constants of scandium complexes with some carboxylate ligands were determined potentiometrically at 25.0 and 40.0 0 C and at an ionic strength of 0.10 with potassium nitrate as supporting electrolyte. The constants of the scandium complexes were appreciably greater than those of the corresponding lanthanoid complexes, as expected. The changes in free energy, enthalpy, and entropy for the formation of the scandium complexes were calculated from the stability constants at two temperatures. (author)
Iterative Selection of Unknown Weights in Direct Weight Optimization Identification
Directory of Open Access Journals (Sweden)
Xiao Xuan
2014-01-01
Full Text Available To the direct weight optimization identification of the nonlinear system, we add some linear terms about input sequences in the former linear affine function so as to approximate the nonlinear property. To choose the two classes of unknown weights in the more linear terms, this paper derives the detailed process on how to choose these unknown weights from theoretical analysis and engineering practice, respectively, and makes sure of their key roles between the unknown weights. From the theoretical analysis, the added unknown weights’ auxiliary role can be known in the whole process of approximating the nonlinear system. From the practical analysis, we learn how to transform one complex optimization problem to its corresponding common quadratic program problem. Then, the common quadratic program problem can be solved by the basic interior point method. Finally, the efficiency and possibility of the proposed strategies can be confirmed by the simulation results.
The Unknown Computer Viruses Detection Based on Similarity
Liu, Zhongda; Nakaya, Naoshi; Koui, Yuuji
New computer viruses are continually being generated and they cause damage all over the world. In general, current anti-virus software detects viruses by matching a pattern based on the signature; thus, unknown viruses without any signature cannot be detected. Although there are some static analysis technologies that do not depend on signatures, virus writers often use code obfuscation techniques, which make it difficult to execute a code analysis. As is generally known, unknown viruses and known viruses share a common feature. In this paper we propose a new static analysis technology that can circumvent code obfuscation to extract the common feature and detect unknown viruses based on similarity. The results of evaluation experiments demonstrated that this technique is able to detect unknown viruses without false positives.
Using the Wheatstone Bridge to Compute Unknown Resistances.
Schlenker, Richard M.
This document presents a secondary level physics unit which introduces students to the Wheatstone Bridge, its use in determining the value of unknown resistors, and the effects of wiring resistors in series or in parallel. (SL)
Stochastic Online Learning in Dynamic Networks under Unknown Models
2016-08-02
Stochastic Online Learning in Dynamic Networks under Unknown Models This research aims to develop fundamental theories and practical algorithms for...12211 Research Triangle Park, NC 27709-2211 Online learning , multi-armed bandit, dynamic networks REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S... Online Learning in Dynamic Networks under Unknown Models Report Title This research aims to develop fundamental theories and practical algorithms for
Fundamental Physical Constants: Looking from Different Angles
Karshenboim, Savely G.
2005-01-01
We consider fundamental physical constants which are among a few of the most important pieces of information we have learned about Nature after its intensive centuries-long studies. We discuss their multifunctional role in modern physics including problems related to the art of measurement, natural and practical units, origin of the constants, their possible calculability and variability etc.
Constant Width Planar Computation Characterizes ACC0
DEFF Research Database (Denmark)
Hansen, K.A.
2004-01-01
We obtain a characterization of ACC 0 in terms of a natural class of constant width circuits, namely in terms of constant width polynomial size planar circuits. This is shown via a characterization of the class of acyclic digraphs which can be embedded on a cylinder surface in such a way that all...
Constant Width Planar Computation Characterizes ACC0
DEFF Research Database (Denmark)
Hansen, Kristoffer Arnsfelt
2006-01-01
We obtain a characterization of ACC0 in terms of a natural class of constant width circuits, namely in terms of constant width polynomial size planar circuits. This is shown via a characterization of the class of acyclic digraphs which can be embedded on a cylinder surface in such a way that all...
Stability constants for silicate adsorbed to ferrihydrite
DEFF Research Database (Denmark)
Hansen, Hans Christian Bruun; Wetche, T.P.; Raulund-Rasmussen, Karsten
1994-01-01
Intrinsic surface acidity constants (K(a1)intr, K(a2)intr) and surface complexation constant for adsorption of orthosilicate onto synthetic ferrihydrite (K(Si) for the complex = FeOSi(OH)3) have been determined from acid/base titrations in 0.001-0.1 m NaClO4 electrolytes and silicate adsorption...
On special relativity with cosmological constant
International Nuclear Information System (INIS)
Guo Hanying; Huang Chaoguang; Xu Zhan; Zhou Bin
2004-01-01
Based on the principle of relativity and the postulate of invariant speed and length, we propose the theory of special relativity with cosmological constant SRc,R, in which the cosmological constant is linked with the invariant length. Its relation with the doubly special relativity is briefly mentioned
The case for the cosmological constant
Indian Academy of Sciences (India)
I present a short overview of current observational results and theoretical models for a cosmological constant. The main motivation for invoking a small cosmological constant (or -term) at the present epoch has to do with observations of high redshift Type Ia supernovae which suggest an accelerating universe.
Some zero-sum constants with weights
Indian Academy of Sciences (India)
to zero-sum problems, Discrete Math. 306 (2006) 1–10. [2] Adhikari S D and Chen Y G, Davenport constant with weights and some related ques- tions – II, J. Combin. Theory A115 (2008) 178–184. [3] Adhikari Sukumar Das and Rath Purusottam, Davenport constant with weights and some related questions, Integers 6 ...
The time constant of the somatogravic illusion.
Correia Grácio, B J; de Winkel, K N; Groen, E L; Wentink, M; Bos, J E
2013-02-01
Without visual feedback, humans perceive tilt when experiencing a sustained linear acceleration. This tilt illusion is commonly referred to as the somatogravic illusion. Although the physiological basis of the illusion seems to be well understood, the dynamic behavior is still subject to discussion. In this study, the dynamic behavior of the illusion was measured experimentally for three motion profiles with different frequency content. Subjects were exposed to pure centripetal accelerations in the lateral direction and were asked to indicate their tilt percept by means of a joystick. Variable-radius centrifugation during constant angular rotation was used to generate these motion profiles. Two self-motion perception models were fitted to the experimental data and were used to obtain the time constant of the somatogravic illusion. Results showed that the time constant of the somatogravic illusion was on the order of two seconds, in contrast to the higher time constant found in fixed-radius centrifugation studies. Furthermore, the time constant was significantly affected by the frequency content of the motion profiles. Motion profiles with higher frequency content revealed shorter time constants which cannot be explained by self-motion perception models that assume a fixed time constant. Therefore, these models need to be improved with a mechanism that deals with this variable time constant. Apart from the fundamental importance, these results also have practical consequences for the simulation of sustained accelerations in motion simulators.
The case for the cosmological constant
Indian Academy of Sciences (India)
Abstract. I present a short overview of current observational results and theoretical models for a cosmological constant. The main motivation for invoking a small cosmological constant (orA-term) at the present epoch has to do with observations of high redshift Type Ia supernovae which suggest an accelerating universe.
Equilibrium-constant expressions for aqueous plutonium
International Nuclear Information System (INIS)
Silver, G.L.
2010-01-01
Equilibrium-constant expressions for Pu disproportionation reactions traditionally contain three or four terms representing the concentrations or fractions of the oxidation states. The expressions can be rewritten so that one of the oxidation states is replaced by a term containing the oxidation number of the plutonium. Experimental estimations of the numerical values of the constants can then be checked in several ways. (author)
DETERMINATION OF STABILITY CONSTANTS OF MANGANESE (II ...
African Journals Online (AJOL)
DR. AMINU
Keywords: Amino acids, dissociation constant, potentiometry, stability constant. INTRODUCTION. Acids – base titration involves the gradual addition or removal of protons for example using the deprotic form of glycine. The plot has two distinct stages corresponding to the deprotonation of the two different groups on glycine.
Graviton fluctuations erase the cosmological constant
Wetterich, C.
2017-10-01
Graviton fluctuations induce strong non-perturbative infrared renormalization effects for the cosmological constant. The functional renormalization flow drives a positive cosmological constant towards zero, solving the cosmological constant problem without the need to tune parameters. We propose a simple computation of the graviton contribution to the flow of the effective potential for scalar fields. Within variable gravity, with effective Planck mass proportional to the scalar field, we find that the potential increases asymptotically at most quadratically with the scalar field. The solutions of the derived cosmological equations lead to an asymptotically vanishing cosmological ;constant; in the infinite future, providing for dynamical dark energy in the present cosmological epoch. Beyond a solution of the cosmological constant problem, our simplified computation also entails a sizeable positive graviton-induced anomalous dimension for the quartic Higgs coupling in the ultraviolet regime, substantiating the successful prediction of the Higgs boson mass within the asymptotic safety scenario for quantum gravity.
Tadpole diagrams in constant electromagnetic fields
Karbstein, Felix
2017-10-01
We show how all possible one-particle reducible tadpole diagrams in constant electromagnetic fields can be constructed from one-particle irreducible constant-field diagrams. The construction procedure is essentially algebraic and involves differentiations of the latter class of diagrams with respect to the field strength tensor and contractions with derivatives of the one-particle irreducible part of the Heisenberg-Euler effective Lagrangian in constant fields. Specific examples include the two-loop addendum to the Heisenberg-Euler effective action as well as a novel one-loop correction to the charged particle propagator in constant electromagnetic fields discovered recently. As an additional example, the approach devised in the present article is adopted to derive the tadpole contribution to the two-loop photon polarization tensor in constant fields for the first time.
Solar constant values for estimating solar radiation
International Nuclear Information System (INIS)
Li, Huashan; Lian, Yongwang; Wang, Xianlong; Ma, Weibin; Zhao, Liang
2011-01-01
There are many solar constant values given and adopted by researchers, leading to confusion in estimating solar radiation. In this study, some solar constant values collected from literature for estimating solar radiation with the Angstroem-Prescott correlation are tested in China using the measured data between 1971 and 2000. According to the ranking method based on the t-statistic, a strategy to select the best solar constant value for estimating the monthly average daily global solar radiation with the Angstroem-Prescott correlation is proposed. -- Research highlights: → The effect of the solar constant on estimating solar radiation is investigated. → The investigation covers a diverse range of climate and geography in China. → A strategy to select the best solar constant for estimating radiation is proposed.
On Semi-classical Degravitation and the Cosmological Constant Problems
Patil, Subodh P
2010-01-01
In this report, we discuss a candidate mechanism through which one might address the various cosmological constant problems. We first observe that the renormalization of gravitational couplings (induced by integrating out various matter fields) manifests non-local modifications to Einstein's equations as quantum corrected equations of motion. That is, at the loop level, matter sources curvature through a gravitational coupling that is a non-local function of the covariant d'Alembertian. If the functional form of the resulting Newton's `constant' is such that it annihilates very long wavelength sources, but reduces to $1/M^2_{pl}$ ($M_{pl}$ being the 4d Planck mass) for all sources with cosmologically observable wavelengths, we would have a complimentary realization of the degravitation paradigm-- a realization through which its non-linear completion and the corresponding modified Bianchi identities are readily understood. We proceed to consider various theories whose coupling to gravity may a priori induce no...
Zhong, Zhixiong; Zhu, Yanzheng; Ahn, Choon Ki
2018-03-20
In this paper, we address the problem of reachable set estimation for continuous-time Takagi-Sugeno (T-S) fuzzy systems subject to unknown output delays. Based on the reachable set concept, a new controller design method is also discussed for such systems. An effective method is developed to attenuate the negative impact from the unknown output delays, which likely degrade the performance/stability of systems. First, an augmented fuzzy observer is proposed to capacitate a synchronous estimation for the system state and the disturbance term owing to the unknown output delays, which ensures that the reachable set of the estimation error is limited via the intersection operation of ellipsoids. Then, a compensation technique is employed to eliminate the influence on the system performance stemmed from the unknown output delays. Finally, the effectiveness and correctness of the obtained theories are verified by the tracking control of autonomous underwater vehicles. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.
Magnuson, Matthew L; Satzger, R Duane; Alcaraz, Armando; Brewer, Jason; Fetterolf, Dean; Harper, Martin; Hrynchuk, Ronald; McNally, Mary F; Montgomery, Madeline; Nottingham, Eric; Peterson, James; Rickenbach, Michael; Seidel, Jimmy L; Wolnik, Karen
2012-05-01
Since the early 1990s, the FBI Laboratory has sponsored Scientific Working Groups to improve discipline practices and build consensus among the forensic community. The Scientific Working Group on the Forensic Analysis of Chemical, Biological, Radiological and Nuclear Terrorism developed guidance, contained in this document, on issues forensic laboratories encounter when accepting and analyzing unknown samples associated with chemical terrorism, including laboratory capabilities and analytical testing plans. In the context of forensic analysis of chemical terrorism, this guidance defines an unknown sample and addresses what constitutes definitive and tentative identification. Laboratory safety, reporting issues, and postreporting considerations are also discussed. Utilization of these guidelines, as part of planning for forensic analysis related to a chemical terrorism incident, may help avoid unfortunate consequences not only to the public but also to the laboratory personnel. 2011 American Academy of Forensic Sciences. Published 2011. This article is a U.S. Government work and is in the public domain in the U.S.A.
Constant strength fuel-fuel cell
International Nuclear Information System (INIS)
Vaseen, V.A.
1980-01-01
A fuel cell is an electrochemical apparatus composed of both a nonconsumable anode and cathode; and electrolyte, fuel oxidant and controls. This invention guarantees the constant transfer of hydrogen atoms and their respective electrons, thus a constant flow of power by submergence of the negative electrode in a constant strength hydrogen furnishing fuel; when said fuel is an aqueous absorbed hydrocarbon, such as and similar to ethanol or methnol. The objective is accomplished by recirculation of the liquid fuel, as depleted in the cell through specific type membranes which pass water molecules and reject the fuel molecules; thus concentrating them for recycle use
On the constants for some Sobolev imbeddings
Directory of Open Access Journals (Sweden)
Pizzocchero Livio
2001-01-01
Full Text Available We consider the imbedding inequality is the Sobolev space (or Bessel potential space of type and (integer or fractional order . We write down upper bounds for the constants , using an argument previously applied in the literature in particular cases. We prove that the upper bounds computed in this way are in fact the sharp constants if , , and exhibit the maximising functions. Furthermore, using convenient trial functions, we derive lower bounds on for in many cases these are close to the previous upper bounds, as illustrated by a number of examples, thus characterizing the sharp constants with little uncertainty.
On the constant-roll inflation
Yi, Zhu; Gong, Yungui
2018-03-01
The primordial power spectra of scalar and tensor perturbations during slow-roll inflation are usually calculated with the method of Bessel function approximation. For constant-roll or ultra slow-roll inflation, the method of Bessel function approximation may be invalid. We compare the numerical results with the analytical results derived from the Bessel function approximation, and we find that they differ significantly on super-horizon scales if the constant slow-roll parameter ηH is not small. More accurate method is needed for calculating the primordial power spectrum for constant-roll inflation.
Cosmological constant and advanced gravitational wave detectors
International Nuclear Information System (INIS)
Wang, Y.; Turner, E.L.
1997-01-01
Interferometric gravitational wave detectors could measure the frequency sweep of a binary inspiral (characterized by its chirp mass) to high accuracy. The observed chirp mass is the intrinsic chirp mass of the binary source multiplied by (1+z), where z is the redshift of the source. Assuming a nonzero cosmological constant, we compute the expected redshift distribution of observed events for an advanced LIGO detector. We find that the redshift distribution has a robust and sizable dependence on the cosmological constant; the data from advanced LIGO detectors could provide an independent measurement of the cosmological constant. copyright 1997 The American Physical Society
Addressing adolescent pregnancy with legislation.
Montgomery, Tiffany M; Folken, Lori; Seitz, Melody A
2014-01-01
Adolescent pregnancy is a concern among many women's health practitioners. While it is practical and appropriate to work to prevent adolescent pregnancy by educating adolescents in health care clinics, schools and adolescent-friendly community-based organizations, suggesting and supporting legislative efforts to reduce adolescent pregnancy can help address the issue on an even larger scale. This article aims to help nurses better understand current legislation that addresses adolescent pregnancy, and to encourage support of future adolescent pregnancy prevention legislation. © 2014 AWHONN.
Grasping Unknown Objects in an Early Cognitive Vision System
DEFF Research Database (Denmark)
Popovic, Mila
2011-01-01
Grasping of unknown objects presents an important and challenging part of robot manipulation. The growing area of service robotics depends upon the ability of robots to autonomously grasp and manipulate a wide range of objects in everyday environments. Simple, non task-specific grasps of unknown ...... and comparing vision-based grasping methods, and the creation of algorithms for bootstrapping a process of acquiring world understanding for artificial cognitive agents....... presents a system for robotic grasping of unknown objects us- ing stereo vision. Grasps are defined based on contour and surface information provided by the Early Cognitive Vision System, that organizes visual informa- tion into a biologically motivated hierarchical representation. The contributions...... of the thesis are: the extension of the Early Cognitive Vision representation with a new type of feature hierarchy in the texture domain, the definition and evaluation of contour based grasping methods, the definition and evaluation of surface based grasping methods, the definition of a benchmark for testing...
Interacting universes and the cosmological constant
Energy Technology Data Exchange (ETDEWEB)
Alonso-Serrano, A. [Centro de Física “Miguel Catalán”, Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 121, 28006 Madrid (Spain); Estación Ecológica de Biocosmología, Pedro de Alvarado 14, 06411 Medellín (Spain); Bastos, C. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Avenida Rovisco Pais 1, 1049-001 Lisboa (Portugal); Bertolami, O. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Avenida Rovisco Pais 1, 1049-001 Lisboa (Portugal); Departamento de Física e Astronomia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto (Portugal); Robles-Pérez, S., E-mail: salvarp@imaff.cfmac.csic.es [Centro de Física “Miguel Catalán”, Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 121, 28006 Madrid (Spain); Estación Ecológica de Biocosmología, Pedro de Alvarado 14, 06411 Medellín (Spain); Física Teórica, Universidad del País Vasco, Apartado 644, 48080 Bilbao (Spain)
2013-02-12
In this Letter it is studied the effects that an interaction scheme among universes can have in the values of their cosmological constants. In the case of two interacting universes, the value of the cosmological constant of one of the universes becomes very close to zero at the expense of an increasing value of the cosmological constant of the partner universe. In the more general case of a chain of N interacting universes with periodic boundary conditions, the spectrum of the Hamiltonian splits into a large number of levels, each of them associated with a particular value of the cosmological constant, that can be occupied by single universes revealing a collective behavior that plainly shows that the multiverse is much more than the mere sum of its parts.
An improved dosimeter having constant flow pump
International Nuclear Information System (INIS)
Baker, W.B.
1980-01-01
A dosemeter designed for individual use which can be used to monitor toxic radon gas and toxic related products of radon gas in mines and which incorporates a constant air stream flowing through the dosimeter is described. (U.K.)
Constant conditional entropy and related hypotheses
International Nuclear Information System (INIS)
Ferrer-i-Cancho, Ramon; Dębowski, Łukasz; Moscoso del Prado Martín, Fermín
2013-01-01
Constant entropy rate (conditional entropies must remain constant as the sequence length increases) and uniform information density (conditional probabilities must remain constant as the sequence length increases) are two information theoretic principles that are argued to underlie a wide range of linguistic phenomena. Here we revise the predictions of these principles in the light of Hilberg’s law on the scaling of conditional entropy in language and related laws. We show that constant entropy rate (CER) and two interpretations for uniform information density (UID), full UID and strong UID, are inconsistent with these laws. Strong UID implies CER but the reverse is not true. Full UID, a particular case of UID, leads to costly uncorrelated sequences that are totally unrealistic. We conclude that CER and its particular cases are incomplete hypotheses about the scaling of conditional entropies. (letter)
Interacting universes and the cosmological constant
International Nuclear Information System (INIS)
Alonso-Serrano, A.; Bastos, C.; Bertolami, O.; Robles-Pérez, S.
2013-01-01
In this Letter it is studied the effects that an interaction scheme among universes can have in the values of their cosmological constants. In the case of two interacting universes, the value of the cosmological constant of one of the universes becomes very close to zero at the expense of an increasing value of the cosmological constant of the partner universe. In the more general case of a chain of N interacting universes with periodic boundary conditions, the spectrum of the Hamiltonian splits into a large number of levels, each of them associated with a particular value of the cosmological constant, that can be occupied by single universes revealing a collective behavior that plainly shows that the multiverse is much more than the mere sum of its parts
Hydrolysis and formation constants at 250C
International Nuclear Information System (INIS)
Phillips, S.L.
1982-05-01
A database consisting of hydrolysis and formation constants for about 20 metals associated with the disposal of nuclear waste is given. Complexing ligands for the various ionic species of these metals include OH, F, Cl, SO 4 , PO 4 and CO 3 . Table 1 consists of tabulated calculated and experimental values of log K/sub xy/, mainly at 25 0 C and various ionic strengths together with references to the origin of the data. Table 2 consists of a column of recommended stability constants at 25 0 C and zero ionic strength tabulated in the column headed log K/sub xy/(0); other columns contain coefficients for an extended Debye-Huckel equation to permit calculations of stability constants up to 3 ionic strength, and up to 0.7 ionic strength using the Davies equation. Selected stability constants calculated with these coefficients for various ionic strengths agree to an average of +- 2% when compared with published experimental and calculated values
Molecular toolbox for the identification of unknown genetically modified organisms.
Ruttink, Tom; Demeyer, Rolinde; Van Gulck, Elke; Van Droogenbroeck, Bart; Querci, Maddalena; Taverniers, Isabel; De Loose, Marc
2010-03-01
Competent laboratories monitor genetically modified organisms (GMOs) and products derived thereof in the food and feed chain in the framework of labeling and traceability legislation. In addition, screening is performed to detect the unauthorized presence of GMOs including asynchronously authorized GMOs or GMOs that are not officially registered for commercialization (unknown GMOs). Currently, unauthorized or unknown events are detected by screening blind samples for commonly used transgenic elements, such as p35S or t-nos. If (1) positive detection of such screening elements shows the presence of transgenic material and (2) all known GMOs are tested by event-specific methods but are not detected, then the presence of an unknown GMO is inferred. However, such evidence is indirect because it is based on negative observations and inconclusive because the procedure does not identify the causative event per se. In addition, detection of unknown events is hampered in products that also contain known authorized events. Here, we outline alternative approaches for analytical detection and GMO identification and develop new methods to complement the existing routine screening procedure. We developed a fluorescent anchor-polymerase chain reaction (PCR) method for the identification of the sequences flanking the p35S and t-nos screening elements. Thus, anchor-PCR fingerprinting allows the detection of unique discriminative signals per event. In addition, we established a collection of in silico calculated fingerprints of known events to support interpretation of experimentally generated anchor-PCR GM fingerprints of blind samples. Here, we first describe the molecular characterization of a novel GMO, which expresses recombinant human intrinsic factor in Arabidopsis thaliana. Next, we purposefully treated the novel GMO as a blind sample to simulate how the new methods lead to the molecular identification of a novel unknown event without prior knowledge of its transgene
A quadri-constant fraction discriminator
International Nuclear Information System (INIS)
Wang Wei; Gu Zhongdao
1992-01-01
A quad Constant Fraction (Amplitude and Rise Time Compensation) Discriminator Circuit is described, which is based on the ECL high-speed dual comparator AD 9687. The CFD (ARCD) is of the constant fraction timing type (the amplitude and rise time compensation timing type) employing a leading edge discriminator to eliminate error triggers caused by noises. A timing walk measurement indicates a timing walk of less than +- 150 ps from -50 mV to -5 V
Building evolutionary architectures support constant change
Ford, Neal; Kua, Patrick
2017-01-01
The software development ecosystem is constantly changing, providing a constant stream of new tools, frameworks, techniques, and paradigms. Over the past few years, incremental developments in core engineering practices for software development have created the foundations for rethinking how architecture changes over time, along with ways to protect important architectural characteristics as it evolves. This practical guide ties those parts together with a new way to think about architecture and time.
Nuclei quadrupole coupling constants in diatomic molecule
International Nuclear Information System (INIS)
Ivanov, A.I.; Rebane, T.K.
1993-01-01
An approximate relationship between the constants of quadrupole interaction of nuclei in a two-atom molecule is found. It enabled to establish proportionality of oscillatory-rotation corrections to these constants for both nuclei in the molecule. Similar results were obtained for the factors of electrical dipole-quadrupole screening of nuclei. Applicability of these relationships is proven by the example of lithium deuteride molecule. 4 refs., 1 tab
Optical constants of concentrated aqueous ammonium sulfate.
Remsberg, E. E.
1973-01-01
Using experimental data obtained from applying spectroscopy to a 39-wt-% aqueous ammonium sulfate solution, it is shown that, even though specific aerosol optical constants appear quite accurate, spectral variations may exist as functions of material composition or concentration or both. Prudent users of optical constant data must then include liberal data error estimates when performing calculations or in interpreting spectroscopic surveys of collected aerosol material.
Adaptive Incentive Controls for Stackelberg Games with Unknown Cost Functionals.
1984-01-01
APR EZT:: F I AN 73S e OsL:-: UNCLASSI?:-- Q4~.’~- .A.., 6, *~*i i~~*~~*.- U ADAPTIVE INCENTIVE CONTROLS FOR STACKELBERG GAMES WITH UNKNOWN COST...AD-A161 885 ADAPTIVE INCENTIVE CONTROLS FOR STACKELBERG GAMES WITH i/1 UNKNOWN COST FUNCTIONALSCU) ILLINOIS UNIV AT URBANA DECISION AND CONTROL LAB T...ORGANIZATION 6b. OFFICE SYMBOL 7.. NAME OF MONITORING ORGANIZATION CoriaeLcenef~pda~ Joint Services Electronics Program Laboratory, Univ. of Illinois N/A
Biomarkers for Ectopic Pregnancy and Pregnancy of Unknown Location
Senapati, Suneeta; Barnhart, Kurt T.
2013-01-01
Early pregnancy failure is the most common complication of pregnancy, and 1–2% of all pregnancies will be ectopic. As one of the leading causes of maternal morbidity and mortality, diagnosing ectopic pregnancy and determining the fate of a pregnancy of unknown location are of great clinical concern. Several serum and plasma biomarkers for ectopic pregnancy have been investigated independently and in combination. The following is a review of the state of biomarker discovery and development for ectopic pregnancy and pregnancy of unknown location. PMID:23290746
Quantum Sharing an Unknown Multi-Particle State via POVM
Peng, Jia-Yin; Mo, Zhi-Wen
2013-02-01
Our purpose in this paper is to present a new tripartite quantum state sharing using partially quantum resources. The first scheme is to probabilistically split an unknown n-particle state using pre-shared a partially entangled four-particle cluster state as quantum resource by constructing some proper POVM. This scheme is further extended to share an unknown multi-particle cluster state using different states as quantum resources. Our schemes with general quantum channels are useful for various quantum information processing and quantum network tasks.
Prediction of Primary Tumors in Cancers of Unknown Primary
DEFF Research Database (Denmark)
Søndergaard, Dan; Nielsen, Svend; Pedersen, Christian N S
2017-01-01
treatment choice and thus improve the clinical outcome. In this paper, we present a new method for predicting the location of the primary tumor using gene expression data: locating cancers of unknown primary (LoCUP). The method models the data as a mixture of normal and tumor cells and thus allows correct......A cancer of unknown primary (CUP) is a metastatic cancer for which standard diagnostic tests fail to identify the location of the primary tumor. CUPs account for 3-5% of cancer cases. Using molecular data to determine the location of the primary tumor in such cases can help doctors make the right...
Introduction to IP address management
Rooney, Tim
2010-01-01
"The book begins with a basic overview of IP networking, followed by chapters describing each of the three core IPAM technologies: IPv4 and IPv6 addressing, DHCP, and DNS. The next three chapters describe IPAM management techniques and practice, followed by chapters on IPv4-IPv6 co-existence, security and the IPAM business case"--
Shi, Wuxi; Luo, Rui; Li, Baoquan
2017-01-01
In this study, an adaptive fuzzy prescribed performance control approach is developed for a class of uncertain multi-input and multi-output (MIMO) nonlinear systems with unknown control direction and unknown dead-zone inputs. The properties of symmetric matrix are exploited to design adaptive fuzzy prescribed performance controller, and a Nussbaum-type function is incorporated in the controller to estimate the unknown control direction. This method has two prominent advantages: it does not require the priori knowledge of control direction and only three parameters need to be updated on-line for this MIMO systems. It is proved that all the signals in the resulting closed-loop system are bounded and that the tracking errors converge to a small residual set with the prescribed performance bounds. The effectiveness of the proposed approach is validated by simulation results. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.
Liability for Unknown Risks: A Law and Economics Perspective
M.G. Faure (Michael); L.T. Visscher (Louis); F. Weber (Franziska)
2017-01-01
textabstractIn the law and economics literature liability is generally regarded as an instrument which provides potential tortfeasors with incentives for optimal care taking. The question, however, arises whether liability can still provide those incentives when risks are unknown. That is the
Fast grasping of unknown objects using principal component analysis
Lei, Qujiang; Chen, Guangming; Wisse, Martijn
2017-09-01
Fast grasping of unknown objects has crucial impact on the efficiency of robot manipulation especially subjected to unfamiliar environments. In order to accelerate grasping speed of unknown objects, principal component analysis is utilized to direct the grasping process. In particular, a single-view partial point cloud is constructed and grasp candidates are allocated along the principal axis. Force balance optimization is employed to analyze possible graspable areas. The obtained graspable area with the minimal resultant force is the best zone for the final grasping execution. It is shown that an unknown object can be more quickly grasped provided that the component analysis principle axis is determined using single-view partial point cloud. To cope with the grasp uncertainty, robot motion is assisted to obtain a new viewpoint. Virtual exploration and experimental tests are carried out to verify this fast gasping algorithm. Both simulation and experimental tests demonstrated excellent performances based on the results of grasping a series of unknown objects. To minimize the grasping uncertainty, the merits of the robot hardware with two 3D cameras can be utilized to suffice the partial point cloud. As a result of utilizing the robot hardware, the grasping reliance is highly enhanced. Therefore, this research demonstrates practical significance for increasing grasping speed and thus increasing robot efficiency under unpredictable environments.
Prevalence and predictors of unknown HIV status among women ...
African Journals Online (AJOL)
sum test and logistic regression were used to test associations. Results: The prevalence of unknown HIV status was ... and occurs in utero, during labour and delivery and during breastfeeding1. Without any intervention, the MTCT rate ... transport costs to health facilities. Other service delivery factors assessed included ...
Multiple analysis of an unknown optical multilayer coating
International Nuclear Information System (INIS)
Dobrowolski, J.A.; Ho, F.C.; Waldorf, A.
1985-01-01
Results are given of the analysis at five different laboratories of an unknown optical multilayer coating. In all, eleven different analytical and laboratory techniques were applied to the problem. The multilayer nominally consisted of three dielectric and two metallic layers. It was demonstrated convincingly that with present day techniques it is possible to determine the basic structure of such a coating
Clostridium difficile: A healthcare-associated infection of unknown ...
African Journals Online (AJOL)
Clostridium difficile: A healthcare-associated infection of unknown significance in adults in sub-Saharan Africa. ... Abstract. Background: Clostridium difficile infection (CDI) causes a high burden of disease in high-resource healthcare systems, with significant morbidity, mortality, and financial implications. CDI is a ...
Vision-based autonomous grasping of unknown piled objects
International Nuclear Information System (INIS)
Johnson, R.K.
1994-01-01
Computer vision techniques have been used to develop a vision-based grasping capability for autonomously picking and placing unknown piled objects. This work is currently being applied to the problem of hazardous waste sorting in support of the Department of Energy's Mixed Waste Operations Program
Editoria: EBOLA: Fear of the unknown | Comoro | Tanzania Journal ...
African Journals Online (AJOL)
Tanzania Journal of Health Research. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 3, No 2 (2001) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Editoria: EBOLA: Fear of the unknown. C. Comoro, J.
Prevalence and treatment outcome of cervicitis of unknown etiology.
Taylor, Stephanie N; Lensing, Shelly; Schwebke, Jane; Lillis, Rebecca; Mena, Leandro A; Nelson, Anita L; Rinaldi, Anne; Saylor, Lisa; McNeil, Linda; Lee, Jeannette Y
2013-05-01
Mucopurulent cervicitis (MPC) is a clinical syndrome characterized by mucopurulent discharge from the cervix and other signs of inflammation. This was a phase III, multicenter study designed to evaluate the effectiveness of placebo versus empiric antibiotic treatment for clinical cure of MPC of unknown etiology at 2-month follow-up. Unfortunately, enrollment was terminated because of low accrual of women with cervicitis of unknown etiology, but important prevalence and outcome data were obtained. Five hundred seventy-seven women were screened for MPC. Women with MPC were randomized to the treatment or placebo arm of the study, and the 2 arms were evaluated based on the etiology, clinical cure rates, adverse events (AEs), and rates of pelvic inflammatory disease. One hundred thirty-one (23% [131/577]) screened women were found to have MPC. Eighty-seven were enrolled and randomized. After excluding women with sexually transmitted infections and other exclusions, 61% (53/87) had cervicitis of unknown etiology. The overall clinical failure rate was 30% (10/33), and the clinical cure rate was only 24% (8/33). Rates were not significantly different between the arms. There were 24 gastrointestinal AEs in the treatment arm compared with 1 AE in the placebo arm. More than half of the cases of MPC were of unknown etiology. Clinical cure rates for the placebo and treatment arms were extremely low, with most women concluding the study with a partial response. Gastrointestinal AEs were higher in the treatment arm.
Fast grasping of unknown objects using principal component analysis
Directory of Open Access Journals (Sweden)
Qujiang Lei
2017-09-01
Full Text Available Fast grasping of unknown objects has crucial impact on the efficiency of robot manipulation especially subjected to unfamiliar environments. In order to accelerate grasping speed of unknown objects, principal component analysis is utilized to direct the grasping process. In particular, a single-view partial point cloud is constructed and grasp candidates are allocated along the principal axis. Force balance optimization is employed to analyze possible graspable areas. The obtained graspable area with the minimal resultant force is the best zone for the final grasping execution. It is shown that an unknown object can be more quickly grasped provided that the component analysis principle axis is determined using single-view partial point cloud. To cope with the grasp uncertainty, robot motion is assisted to obtain a new viewpoint. Virtual exploration and experimental tests are carried out to verify this fast gasping algorithm. Both simulation and experimental tests demonstrated excellent performances based on the results of grasping a series of unknown objects. To minimize the grasping uncertainty, the merits of the robot hardware with two 3D cameras can be utilized to suffice the partial point cloud. As a result of utilizing the robot hardware, the grasping reliance is highly enhanced. Therefore, this research demonstrates practical significance for increasing grasping speed and thus increasing robot efficiency under unpredictable environments.
Severe scratcher-reaction: an unknown health hazard?
Directory of Open Access Journals (Sweden)
Carsten Sauer Mikkelsen
2015-03-01
Full Text Available Tattoos are well known to cause skin problems and the number of reported adverse reactions after tattooing has increased. Illegally imported tattoo ink is unrestrained and can contain unknown ingredients and contamination thereby posing a serious health hazard. We present a case illustrating the risk of pronounced phototoxic allergic reaction and other severe complications after using home kit tattoo ink.
Bayesian Compressed Sensing with Unknown Measurement Noise Level
DEFF Research Database (Denmark)
Hansen, Thomas Lundgaard; Jørgensen, Peter Bjørn; Pedersen, Niels Lovmand
2013-01-01
In sparse Bayesian learning (SBL) approximate Bayesian inference is applied to find sparse estimates from observations corrupted by additive noise. Current literature only vaguely considers the case where the noise level is unknown a priori. We show that for most state-of-the-art reconstruction a...
Inventory control in case of unknown demand and control parameters
Janssen, E.
2010-01-01
This thesis deals with unknown demand and control parameters in inventory control. Inventory control involves decisions on what to order when and in what quantity. These decisions are based on information about the demand. Models are constructed using complete demand information; these models ensure
A Size Exclusion Chromatography Laboratory with Unknowns for Introductory Students
McIntee, Edward J.; Graham, Kate J.; Colosky, Edward C.; Jakubowski, Henry V.
2015-01-01
Size exclusion chromatography is an important technique in the separation of biological and polymeric samples by molecular weight. While a number of laboratory experiments have been published that use this technique for the purification of large molecules, this is the first report of an experiment that focuses on purifying an unknown small…
Metastatic Carcinoma of Unknown Primary Presenting as Jugular Venous Thrombosis
Directory of Open Access Journals (Sweden)
Prince Cheriyan Modayil
2009-01-01
Full Text Available Jugular venous thrombosis is unusual and is associated with central venous catheterisation, intravenous drug abuse and head and neck sepsis. It is rarely associated with malignancy. We report a case of metastatic carcinoma of unknown primary in a forty year old female which presented with jugular venous thrombosis. The discussion includes investigation and treatment options for this condition.
Exacerbating the Cosmological Constant Problem with Interacting Dark Energy Models.
Marsh, M C David
2017-01-06
Future cosmological surveys will probe the expansion history of the Universe and constrain phenomenological models of dark energy. Such models do not address the fine-tuning problem of the vacuum energy, i.e., the cosmological constant problem (CCP), but can make it spectacularly worse. We show that this is the case for "interacting dark energy" models in which the masses of the dark matter states depend on the dark energy sector. If realized in nature, these models have far-reaching implications for proposed solutions to the CCP that require the number of vacua to exceed the fine-tuning of the vacuum energy density. We show that current estimates of the number of flux vacua in string theory, N_{vac}∼O(10^{272 000}), are far too small to realize certain simple models of interacting dark energy and solve the cosmological constant problem anthropically. These models admit distinctive observational signatures that can be targeted by future gamma-ray observatories, hence making it possible to observationally rule out the anthropic solution to the cosmological constant problem in theories with a finite number of vacua.
Bayesian source term determination with unknown covariance of measurements
Belal, Alkomiet; Tichý, Ondřej; Šmídl, Václav
2017-04-01
Determination of a source term of release of a hazardous material into the atmosphere is a very important task for emergency response. We are concerned with the problem of estimation of the source term in the conventional linear inverse problem, y = Mx, where the relationship between the vector of observations y is described using the source-receptor-sensitivity (SRS) matrix M and the unknown source term x. Since the system is typically ill-conditioned, the problem is recast as an optimization problem minR,B(y - Mx)TR-1(y - Mx) + xTB-1x. The first term minimizes the error of the measurements with covariance matrix R, and the second term is a regularization of the source term. There are different types of regularization arising for different choices of matrices R and B, for example, Tikhonov regularization assumes covariance matrix B as the identity matrix multiplied by scalar parameter. In this contribution, we adopt a Bayesian approach to make inference on the unknown source term x as well as unknown R and B. We assume prior on x to be a Gaussian with zero mean and unknown diagonal covariance matrix B. The covariance matrix of the likelihood R is also unknown. We consider two potential choices of the structure of the matrix R. First is the diagonal matrix and the second is a locally correlated structure using information on topology of the measuring network. Since the inference of the model is intractable, iterative variational Bayes algorithm is used for simultaneous estimation of all model parameters. The practical usefulness of our contribution is demonstrated on an application of the resulting algorithm to real data from the European Tracer Experiment (ETEX). This research is supported by EEA/Norwegian Financial Mechanism under project MSMT-28477/2014 Source-Term Determination of Radionuclide Releases by Inverse Atmospheric Dispersion Modelling (STRADI).
Blind Identification of FIR Channels in the Presence of Unknown Noise
Directory of Open Access Journals (Sweden)
Kon Max Wong
2007-01-01
Full Text Available Blind channel identification techniques based on second-order statistics (SOS of the received data have been a topic of active research in recent years. Among the most popular is the subspace method (SS proposed by Moulines et al. (1995. It has good performance when the channel output is corrupted by white noise. However, when the channel noise is correlated and unknown as is often encountered in practice, the performance of the SS method degrades severely. In this paper, we address the problem of estimating FIR channels in the presence of arbitrarily correlated noise whose covariance matrix is unknown. We propose several algorithms according to the different available system resources: (1 when only one receiving antenna is available, by upsampling the output, we develop the maximum a posteriori (MAP algorithm for which a simple criterion is obtained and an efficient implementation algorithm is developed; (2 when two receiving antennae are available, by upsampling both the outputs and utilizing canonical correlation decomposition (CCD to obtain the subspaces, we present two algorithms (CCD-SS and CCD-ML to blindly estimate the channels. Our algorithms perform well in unknown noise environment and outperform existing methods proposed for similar scenarios.
RSS-based localization of isotropically decaying source with unknown power and pathloss factor
International Nuclear Information System (INIS)
Sun, Shunyuan; Sun, Li; Ding, Zhiguo
2016-01-01
This paper addresses the localization of an isotropically decaying source based on the received signal strength (RSS) measurements that are collected from nearby active sensors that are position-known and wirelessly connected, and it propose a novel iterative algorithm for RSS-based source localization in order to improve the location accuracy and realize real-time location and automatic monitoring for hospital patients and medical equipment in the smart hospital. In particular, we consider the general case where the source power and pathloss factor are both unknown. For such a source localization problem, we propose an iterative algorithm, in which the unknown source position and two other unknown parameters (i.e. the source power and pathloss factor) are estimated in an alternating way based on each other, with our proposed sub-optimum initial estimate on source position obtained based on the RSS measurements that are collected from a few (closest) active sensors with largest RSS values. Analysis and simulation study show that our proposed iterative algorithm guarantees globally convergence to the least-squares (LS) solution, where for our suitably assumed independent and identically distributed (i.i.d.) zero-mean Gaussian RSS measurement errors the converged localization performance achieves the optimum that corresponds to the Cramer–Rao lower bound (CRLB).
Directory of Open Access Journals (Sweden)
Yang Xiao-Jun
2017-01-01
Full Text Available In this paper, we address a class of the fractional derivatives of constant and variable orders for the first time. Fractional-order relaxation equations of constants and variable orders in the sense of Caputo type are modeled from mathematical view of point. The comparative results of the anomalous relaxation among the various fractional derivatives are also given. They are very efficient in description of the complex phenomenon arising in heat transfer.
Derivation of the optical constants of anisotropic
Aronson, J. R.; Emslie, A. G.; Smith, E. M.; Strong, P. F.
1985-07-01
This report concerns the development of methods for obtaining the optical constants of anisotropic crystals of the triclinic and monoclinic systems. The principal method used, classical dispersion theory, is adapted to these crystal systems by extending the Lorentz line parameters to include the angles characterizing the individual resonances, and by replacing the dielectric constant by a dielectric tensor. The sample crystals are gypsium, orthoclase and chalcanthite. The derived optical constants are shown to be suitable for modeling the optical properties of particulate media in the infrared spectral region. For those materials where suitable size single crystals are not available, an extension of a previously used method is applied to alabaster, a polycrystalline material of the monoclinic crystal system.
Fast optimization algorithms and the cosmological constant
Bao, Ning; Bousso, Raphael; Jordan, Stephen; Lackey, Brad
2017-11-01
Denef and Douglas have observed that in certain landscape models the problem of finding small values of the cosmological constant is a large instance of a problem that is hard for the complexity class NP (Nondeterministic Polynomial-time). The number of elementary operations (quantum gates) needed to solve this problem by brute force search exceeds the estimated computational capacity of the observable Universe. Here we describe a way out of this puzzling circumstance: despite being NP-hard, the problem of finding a small cosmological constant can be attacked by more sophisticated algorithms whose performance vastly exceeds brute force search. In fact, in some parameter regimes the average-case complexity is polynomial. We demonstrate this by explicitly finding a cosmological constant of order 10-120 in a randomly generated 1 09-dimensional Arkani-Hamed-Dimopoulos-Kachru landscape.
Stability constants for silicate adsorbed to ferrihydrite
DEFF Research Database (Denmark)
Hansen, Hans Christian Bruun; Wetche, T.P.; Raulund-Rasmussen, Karsten
1994-01-01
Intrinsic surface acidity constants (K(a1)intr, K(a2)intr) and surface complexation constant for adsorption of orthosilicate onto synthetic ferrihydrite (K(Si) for the complex = FeOSi(OH)3) have been determined from acid/base titrations in 0.001-0.1 m NaClO4 electrolytes and silicate adsorption...... experiments in 0.01 m NaNO3 electrolyte (pH 3-6). The surface equilibrium constants were calculated according to the two-layer model by Dzombak & Morel (1990). Near equilibrium between protons/hydroxyls in solution and the ferrihydrite surface was obtained within minutes while equilibration with silicate...
Effects of quantum entropy on bag constant
International Nuclear Information System (INIS)
Miller, D.E.; Tawfik, A.
2012-01-01
The effects of quantum entropy on the bag constant are studied at low temperatures and for small chemical potentials. The inclusion of the quantum entropy of the quarks in the equation of state provides the hadronic bag with an additional heat which causes a decrease in the effective latent heat inside the bag. We have considered two types of baryonic bags, Δ and Ω - . In both cases we have found that the bag constant without the quantum entropy almost does not change with temperature and quark chemical potential. The contribution from the quantum entropy to the equation of state clearly decreases the value of the bag constant. Furthermore, we construct states densities for quarks using the 'Thomas Fermi model' and take into consideration a thermal potential for the interaction. (author)
Conformally invariant braneworld and the cosmological constant
International Nuclear Information System (INIS)
Guendelman, E.I.
2004-01-01
A six-dimensional braneworld scenario based on a model describing the interaction of gravity, gauge fields and 3+1 branes in a conformally invariant way is described. The action of the model is defined using a measure of integration built of degrees of freedom independent of the metric. There is no need to fine tune any bulk cosmological constant or the tension of the two (in the scenario described here) parallel branes to obtain zero cosmological constant, the only solutions are those with zero 4D cosmological constant. The two extra dimensions are compactified in a 'football' fashion and the branes lie on the two opposite poles of the compact 'football-shaped' sphere
Construction and experimental testing of the constant-bandwidth constant-temperature anemometer.
Ligeza, P
2008-09-01
A classical constant-temperature hot-wire anemometer enables the measurement of fast-changing flow velocity fluctuations, although its transmission bandwidth is a function of measured velocity. This may be a source of significant dynamic errors. Incorporation of an adaptive controller into the constant-temperature system results in hot-wire anemometer operating with a constant transmission bandwidth. The construction together with the results of experimental testing of a constant-bandwidth hot-wire anemometer prototype are presented in this article. During the testing, an approximately constant transmission bandwidth of the anemometer was achieved. The constant-bandwidth hot-wire anemometer can be used in measurements of high-frequency variable flows characterized by a wide range of velocity changes.
Cosmological constant, supersymmetry, nonassociativity, and big numbers
Energy Technology Data Exchange (ETDEWEB)
Dzhunushaliev, Vladimir [KazNU, Department of Theoretical and Nuclear Physics, Almaty (Kazakhstan); IETP, Al-Farabi KazNU, Almaty (Kazakhstan)
2015-02-01
The nonassociative generalization of supersymmetry is considered. It is shown that the associator of four supersymmetry generators has the coefficient ∝ ℎ/l{sub 0}{sup 2} where l0 is some characteristic length. Two cases are considered: (a) l{sub 0}{sup -2} coincides with the cosmological constant; (b) l{sub 0} is the classical radius of the electron. It is also shown that the scaled constant is of the order of 10{sup -120} for the first case and 10{sup -30} for the second case. The possible manifestation and smallness of nonassociativity is discussed. (orig.)
The Cosmological Constant Problem (2/2)
CERN. Geneva
2015-01-01
I will review the cosmological constant problem as a serious challenge to our notion of naturalness in Physics. Weinberg’s no go theorem is worked through in detail. I review a number of proposals possibly including Linde's universe multiplication, Coleman's wormholes, the fat graviton, and SLED, to name a few. Large distance modifications of gravity are also discussed, with causality considerations pointing towards a global modification as being the most sensible option. The global nature of the cosmological constant problem is also emphasized, and as a result, the sequestering scenario is reviewed in some detail, demonstrating the cancellation of the Standard Model vacuum energy through a global modification of General Relativity.
The Cosmological Constant Problem (1/2)
CERN. Geneva
2015-01-01
I will review the cosmological constant problem as a serious challenge to our notion of naturalness in Physics. Weinberg’s no go theorem is worked through in detail. I review a number of proposals possibly including Linde's universe multiplication, Coleman's wormholes, the fat graviton, and SLED, to name a few. Large distance modifications of gravity are also discussed, with causality considerations pointing towards a global modification as being the most sensible option. The global nature of the cosmological constant problem is also emphasized, and as a result, the sequestering scenario is reviewed in some detail, demonstrating the cancellation of the Standard Model vacuum energy through a global modification of General Relativity.
Atomic weights: no longer constants of nature
Coplen, Tyler B.; Holden, Norman E.
2011-01-01
Many of us were taught that the standard atomic weights we found in the back of our chemistry textbooks or on the Periodic Table of the Chemical Elements hanging on the wall of our chemistry classroom are constants of nature. This was common knowledge for more than a century and a half, but not anymore. The following text explains how advances in chemical instrumentation and isotopic analysis have changed the way we view atomic weights and why they are no longer constants of nature
Decay constants of heavy-light mesons
International Nuclear Information System (INIS)
Allton, C.R.; Crisafulli, M.; Lubicz, V.; Martinelli, G.; Salina, G.; Bartoloni, A.; Battista, C.; Cabasino, S.; Cabibbo, N.; Marzano, F.; Paolucci, P.S.; Pech, J.; Rapuano, F.; Sarno, R.; Todesco, G.M.; Torelli, M.; Tross, W.; Vicini, P.
1994-01-01
The decay constants of the heavy-light pseudoscalar mesons are studied in a high statistics run using the Wilson action at β=6.0 and β=6.2, and the clover action at β=6.0. The systematics of O(a) discretisation errors are discussed. Our best estimates of the decay constants are: f D =218(9) MeV, f D /f D s =1.11(1) and we obtain preliminary values for f B . (orig.)
Addressing health literacy in patient decision aids
2013-01-01
in which health literacy needs were addressed. Conclusion Lower health literacy affects key decision-making outcomes, but few existing PtDAs have addressed the needs of lower health literacy users. The specific effects of PtDAs designed to mitigate the influence of low health literacy are unknown. More attention to the needs of patients with lower health literacy is indicated, to ensure that PtDAs are appropriate for lower as well as higher health literacy patients. PMID:24624970
Time-Varying FOPDT System Identification with Unknown Disturbance Input
DEFF Research Database (Denmark)
Sun, Zhen; Yang, Zhenyu
2012-01-01
The Time-Varying First Order Plus Dead Time (TV-FOPDT) model is an extension of the conventional FOPDT by allowing the system parameters, which are primarily defined on the transfer function description, i.e., the DC-gain, time constant and time delay, to be time dependent. The TV-FOPDT identific...
Lattice theta constants vs Riemann theta constants and NSR superstring measures
International Nuclear Information System (INIS)
Dunin-Barkowski, P.; Morozov, A.; Sleptsov, A.
2009-01-01
We discuss relations between two different representations of hypothetical holomorphic NSR measures, based on two different ways of constructing the semi-modular forms of weight 8. One of these ways is to build forms from the ordinary Riemann theta constants and another - from the lattice theta constants. We discuss unexpectedly elegant relations between lattice theta constants, corresponding to 16-dimensional self-dual lattices, and Riemann theta constants and present explicit formulae expressing the former ones through the latter. Starting from genus 5 the modular-form approach to construction of NSR measures is clearly sick and it seems to fail completely already at genus 6.
Towards high-speed autonomous navigation of unknown environments
Richter, Charles; Roy, Nicholas
2015-05-01
In this paper, we summarize recent research enabling high-speed navigation in unknown environments for dynamic robots that perceive the world through onboard sensors. Many existing solutions to this problem guarantee safety by making the conservative assumption that any unknown portion of the map may contain an obstacle, and therefore constrain planned motions to lie entirely within known free space. In this work, we observe that safety constraints may significantly limit performance and that faster navigation is possible if the planner reasons about collision with unobserved obstacles probabilistically. Our overall approach is to use machine learning to approximate the expected costs of collision using the current state of the map and the planned trajectory. Our contribution is to demonstrate fast but safe planning using a learned function to predict future collision probabilities.
Quadrotor Control in the Presence of Unknown Mass Properties
Duivenvoorden, Rikky Ricardo Petrus Rufino
Quadrotor UAVs are popular due to their mechanical simplicity, as well as their capability to hover and vertically take-off and land. As applications diversify, quadrotors are increasingly required to operate under unknown mass properties, for example as a multirole sensor platform or for package delivery operations. The work presented here consists of the derivation of a generalized quadrotor dynamic model without the typical simplifying assumptions on the first and second moments of mass. The maximum payload capacity of a quadrotor in hover, and the observability of the unknown mass properties are discussed. A brief introduction of L1 adaptive control is provided, and three different L 1 adaptive controllers were designed for the Parrot AR.Drone quadrotor. Their tracking and disturbance rejection performance was compared to the baseline nonlinear controller in experiments. Finally, the results of the combination of L1 adaptive control with iterative learning control are presented, showing high performance trajectory tracking under uncertainty.
Learning Unknown Structure in CRFs via Adaptive Gradient Projection Method
Directory of Open Access Journals (Sweden)
Wei Xue
2016-08-01
Full Text Available We study the problem of fitting probabilistic graphical models to the given data when the structure is not known. More specifically, we focus on learning unknown structure in conditional random fields, especially learning both the structure and parameters of a conditional random field model simultaneously. To do this, we first formulate the learning problem as a convex minimization problem by adding an l_2-regularization to the node parameters and a group l_1-regularization to the edge parameters, and then a gradient-based projection method is proposed to solve it which combines an adaptive stepsize selection strategy with a nonmonotone line search. Extensive simulation experiments are presented to show the performance of our approach in solving unknown structure learning problems.
On the emergence of unusual, unfamiliar and unknown climates
Harrington, L. J.; Frame, D.; Joshi, M.; Hawkins, E.; Harrington, L. J.
2016-12-01
The concept of `Time of Emergence' (ToE), which characterizes when significant signals of climate change will emerge from existing variability, is a useful and increasingly common metric. However, its applicability to international policy has been limited by both usage and presentation. Here we present more generalized ToEs and related signal to noise (S/N) ratios, termed unusual, unfamiliar and unknown climates (based on how likely they would be in a human lifetime in the absence of anthropogenic warming), for different emissions scenarios. If transient climate response (TCR) is high, mitigation can delay the onset of "unknown" climates by decades for large sections of the world's population; even if TCR is low, mitigation can delay the onset of "unfamiliar" climates for many people by decades. We then disaggregate the time at which integer S/N values are passed into international groups to show how rapidly these integer S/N values are crossed under different scenarios.
Situation assessment for aggregated vehicle merging at an unknown location
Salaria, Kanupriya; Das, Suman; Hinman, Michael; Salerno, John; Bai, Li
2005-05-01
This paper introduces the merge at a point (MAP) algorithm to detect the vehicles convoys whose destination locations are unknown. The algorithm will predict the merged vehicles identification numbers in an iterative manner. We applied this method using the simulated Ground Moving Target Indicator (GMTI) data. The technique is similar to the dead reckoning and Kalman filtering algorithms. This algorithm consists of following procedures: 1) approximates the destination locations for each vehicle using its tracks, 2) validates what vehicles are going to merge at these predicted destination locations using the minimum error solution (MES), and 3) predicts the future destination locations where the vehicles will be merged at for the next iteration. This algorithm will be iteratively processed until predicted destination locations converge. We can use this algorithm to associate the vehicles that will merge to some unknown destination locations. It also has the potential to identify the convoy names and the threats associated with these vehicle groups.
A New Method of Force Control for Unknown Environments
Directory of Open Access Journals (Sweden)
Vishnu Mallapragada
2007-09-01
Full Text Available Current robotic systems are expected to interact with unknown environment where controlling the interaction forces becomes an important issue. We propose a new control technique for force control on unknown environments that tunes the force controller based on online estimation of the environment parameters. However, the proposed approach overcomes the need for precise estimation of environment parameters, which are needed in many system identification-based force control approaches. This framework uses an artificial neural network (ANN-based proportional-integral (PI-gain scheduling force controller to track the desired force by adjusting control gains such that error in parameter estimation can be accommodated. Experimental results are presented to demonstrate the efficacy of the proposed control framework. Finally, the advantages and limitations of the proposed controller are discussed.
Addressing the workforce pipeline challenge
Energy Technology Data Exchange (ETDEWEB)
Leonard Bond; Kevin Kostelnik; Richard Holman
2006-11-01
A secure and affordable energy supply is essential for achieving U.S. national security, in continuing U.S. prosperity and in laying the foundations to enable future economic growth. To meet this goal the next generation energy workforce in the U.S., in particular those needed to support instrumentation, controls and advanced operations and maintenance, is a critical element. The workforce is aging and a new workforce pipeline, to support both current generation and new build has yet to be established. The paper reviews the challenges and some actions being taken to address this need.
SEOM clinical guideline on unknown primary cancer (2017).
Losa, F; Soler, G; Casado, A; Estival, A; Fernández, I; Giménez, S; Longo, F; Pazo-Cid, R; Salgado, J; Seguí, M Á
2018-01-01
Cancer of unknown primary site is a histologically confirmed cancer that manifests in advanced stage, with no identifiable primary site following standard diagnostic procedures. Patients are initially categorized based on the findings of the initial biopsy: adenocarcinoma, squamous-cell carcinoma, neuroendocrine carcinoma, and poorly differentiated carcinoma. Appropriate patient management requires understanding several clinical and pathological features that aid in identifying several subsets of patients with more responsive tumors.
Unknown Word Processing Method for the Common Sense Judgement System
Tsuchiya, Seiji; Kojima, Kazuhide; Watabe, Hirokazu; Kawaoka, Tsukasa
When we humans receive uncertain information, we interpret it properly, so we can expand the conversation, and take the proper actions. This is possible because we have “common sense” concerning the basic word concept, which is built up from long time experience storing knowledge of our language. Of the common sense we use in our every day lives we think that there are; common sense concerning quantity such as size, weight, speed, time, or place; common sense concerning sense or feeling such as hot, beautiful, or loud; and moreover common sense concerning emotion such as happy or sad. In order to make computers closer to human beings, we think that the construction of a “Common Sense Judgment System” which deals with these kinds of common sense is necessary. When aiming to realize this “Common Sense Judgment System” and trying to make a computer have the same common sense knowledge and judgment ability as human beings, a very important factor is the handling of unknown words. Judgment concerning words which were given to the computer as knowledge before hand, it can refer to that knowledge, and the process will have no problem at all. But when an unknown word, which is not registered as knowledge, is inputted, how to process that word is a very difficult problem. In this paper, by using a concept base, which is made from several electric dictionaries; the degree of association, which is done based on the concept base; neural network, putting the closeness of meaning in consideration, we propose a method of unknown word processing, which connects an inputted unknown word to a representing word that is registered in the judgment knowledge base, and we will verify its effectiveness by experiment applied to the emotional judgment subsystem.
Diagnosis of the cancer of unknown primary origin
International Nuclear Information System (INIS)
Jurisova, S.; Poersoek, S.
2013-01-01
Cancer of unknown primary origin (CUP) is one of the ten most frequent cancers worldwide. It constitutes of 3-5% of all human malignancies. At time of diagnosis patients with CUP present with disseminated metastases without established primary origin. CUP manifests as heterogenous group of mainly epithelial cancers recognised by distinct clinico pathological entities. The diagnostic work-up includes extensive histopathology investigations and modern imaging technology. Nevertheless, the primary tumour remains undetected most of the time. (author)
Evaluation of Unknown Tube Well Depth Using Electrical Resistivity Method
Directory of Open Access Journals (Sweden)
Zainal Abidin Mohd Hazreek
2017-01-01
Full Text Available Electrical resistivity method has increasingly adopted in engineering, environmental, mining and archaeological studies. Systematic and proper studies of unknown civil engineering structure evaluation particularly on tube well depth was rarely being established. Conventionally, camera test or string with weight approach has been used to evaluate unknown tube well depth thus exposed to several restriction due to its expensive and time consuming. Hence, this study focused on evaluation of unknown tube well depth using indirect test with particular reference to electrical resistivity method (ERM.A single spread line of electrical resistivity survey was performed using ABEM SAS 4000 equipment set based on Wenner and Pole-dipole array in line with the tube well position. Electrical resistivity raw data was processed using RES2DINV software producing electrical resistivity tomography (ERT of the subsurface profile studied. Then, electrical resistivity value (ERV obtained from RES2DINV analyses (ERT was extracted and analysed using plotted graph (depth versus ERV specifically at tube well position based on electrical resistivity spread line performed. It was found that both array have shown some good similarity results in term of tube well depth (20 m thus able to verify the result interpreted. Both array have shown some good similarity of ERV representing groundwater (ERV = 10 – 100 Ωm and soil with water (ERV > 100 Ωm at depth of 0 – 20 m and >20 m respectively. All those interpretation have shown good agreement based on verification thru established ERV of earth materials references, geological map and nearest available boreholes data. Hence, this study has shown that the application of ERM was applicable in evaluation of unknown tube well depth which efficient in term of cost, time and environmental sustainable.
Component spectra extraction from terahertz measurements of unknown mixtures.
Li, Xian; Hou, D B; Huang, P J; Cai, J H; Zhang, G X
2015-10-20
The aim of this work is to extract component spectra from unknown mixtures in the terahertz region. To that end, a method, hard modeling factor analysis (HMFA), was applied to resolve terahertz spectral matrices collected from the unknown mixtures. This method does not require any expertise of the user and allows the consideration of nonlinear effects such as peak variations or peak shifts. It describes the spectra using a peak-based nonlinear mathematic model and builds the component spectra automatically by recombination of the resolved peaks through correlation analysis. Meanwhile, modifications on the method were made to take the features of terahertz spectra into account and to deal with the artificial baseline problem that troubles the extraction process of some terahertz spectra. In order to validate the proposed method, simulated wideband terahertz spectra of binary and ternary systems and experimental terahertz absorption spectra of amino acids mixtures were tested. In each test, not only the number of pure components could be correctly predicted but also the identified pure spectra had a good similarity with the true spectra. Moreover, the proposed method associated the molecular motions with the component extraction, making the identification process more physically meaningful and interpretable compared to other methods. The results indicate that the HMFA method with the modifications can be a practical tool for identifying component terahertz spectra in completely unknown mixtures. This work reports the solution to this kind of problem in the terahertz region for the first time, to the best of the authors' knowledge, and represents a significant advance toward exploring physical or chemical mechanisms of unknown complex systems by terahertz spectroscopy.
Adaptive Stabilization for Nonholonomic Systems with Unknown Time Delays
Directory of Open Access Journals (Sweden)
Yuanyuan Wu
2013-01-01
Full Text Available This paper presents an adaptive control strategy for a class of nonholonomic systems in chained form with virtual control coefficients, nonlinear uncertainties, and unknown time delays. State scaling technique and backstepping recursive approach are applied to design a nonlinear state feedback controller, which can guarantee the stabilization of the closed-loop systems. The simulation results are provided to show the effectiveness of the proposed method.
Persistent Surveillance of Transient Events with Unknown Statistics
2016-12-18
that events at each location follow a stochastic process with an unknown rate that is independent of other locations’ rates. Since the events are...case for both the prediction for ex- perts problem [20] and MAB [4], [5]. Unfortunately however, application or extension of these algorithms to the...station is independent of other stations’ rates. We assume that the stations are spatially distributed in the domain and hence the robot must spend a non
Characterizing unknown systematics in large scale structure surveys
International Nuclear Information System (INIS)
Agarwal, Nishant; Ho, Shirley; Myers, Adam D.; Seo, Hee-Jong; Ross, Ashley J.; Bahcall, Neta; Brinkmann, Jonathan; Eisenstein, Daniel J.; Muna, Demitri; Palanque-Delabrouille, Nathalie; Yèche, Christophe; Pâris, Isabelle; Petitjean, Patrick; Schneider, Donald P.; Streblyanska, Alina; Weaver, Benjamin A.
2014-01-01
Photometric large scale structure (LSS) surveys probe the largest volumes in the Universe, but are inevitably limited by systematic uncertainties. Imperfect photometric calibration leads to biases in our measurements of the density fields of LSS tracers such as galaxies and quasars, and as a result in cosmological parameter estimation. Earlier studies have proposed using cross-correlations between different redshift slices or cross-correlations between different surveys to reduce the effects of such systematics. In this paper we develop a method to characterize unknown systematics. We demonstrate that while we do not have sufficient information to correct for unknown systematics in the data, we can obtain an estimate of their magnitude. We define a parameter to estimate contamination from unknown systematics using cross-correlations between different redshift slices and propose discarding bins in the angular power spectrum that lie outside a certain contamination tolerance level. We show that this method improves estimates of the bias using simulated data and further apply it to photometric luminous red galaxies in the Sloan Digital Sky Survey as a case study
Characterizing unknown systematics in large scale structure surveys
Energy Technology Data Exchange (ETDEWEB)
Agarwal, Nishant; Ho, Shirley [McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Seo, Hee-Jong [Berkeley Center for Cosmological Physics, LBL and Department of Physics, University of California, Berkeley, CA 94720 (United States); Ross, Ashley J. [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom); Bahcall, Neta [Princeton University Observatory, Peyton Hall, Princeton, NJ 08544 (United States); Brinkmann, Jonathan [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349 (United States); Eisenstein, Daniel J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Muna, Demitri [Department of Astronomy, Ohio State University, Columbus, OH 43210 (United States); Palanque-Delabrouille, Nathalie; Yèche, Christophe [CEA, Centre de Saclay, Irfu/SPP, F-91191 Gif-sur-Yvette (France); Pâris, Isabelle [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Petitjean, Patrick [Université Paris 6 et CNRS, Institut d' Astrophysique de Paris, 98bis blvd. Arago, 75014 Paris (France); Schneider, Donald P. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Streblyanska, Alina [Instituto de Astrofisica de Canarias (IAC), E-38200 La Laguna, Tenerife (Spain); Weaver, Benjamin A., E-mail: nishanta@andrew.cmu.edu [Center for Cosmology and Particle Physics, New York University, New York, NY 10003 (United States)
2014-04-01
Photometric large scale structure (LSS) surveys probe the largest volumes in the Universe, but are inevitably limited by systematic uncertainties. Imperfect photometric calibration leads to biases in our measurements of the density fields of LSS tracers such as galaxies and quasars, and as a result in cosmological parameter estimation. Earlier studies have proposed using cross-correlations between different redshift slices or cross-correlations between different surveys to reduce the effects of such systematics. In this paper we develop a method to characterize unknown systematics. We demonstrate that while we do not have sufficient information to correct for unknown systematics in the data, we can obtain an estimate of their magnitude. We define a parameter to estimate contamination from unknown systematics using cross-correlations between different redshift slices and propose discarding bins in the angular power spectrum that lie outside a certain contamination tolerance level. We show that this method improves estimates of the bias using simulated data and further apply it to photometric luminous red galaxies in the Sloan Digital Sky Survey as a case study.
Effects of memory colour on colour constancy for unknown coloured objects.
Granzier, Jeroen J M; Gegenfurtner, Karl R
2012-01-01
The perception of an object's colour remains constant despite large variations in the chromaticity of the illumination-colour constancy. Hering suggested that memory colours, the typical colours of objects, could help in estimating the illuminant's colour and therefore be an important factor in establishing colour constancy. Here we test whether the presence of objects with diagnostical colours (fruits, vegetables, etc) within a scene influence colour constancy for unknown coloured objects in the scene. Subjects matched one of four Munsell papers placed in a scene illuminated under either a reddish or a greenish lamp with the Munsell book of colour illuminated by a neutral lamp. The Munsell papers were embedded in four different scenes-one scene containing diagnostically coloured objects, one scene containing incongruent coloured objects, a third scene with geometrical objects of the same colour as the diagnostically coloured objects, and one scene containing non-diagnostically coloured objects (eg, a yellow coffee mug). All objects were placed against a black background. Colour constancy was on average significantly higher for the scene containing the diagnostically coloured objects compared with the other scenes tested. We conclude that the colours of familiar objects help in obtaining colour constancy for unknown objects.
Effects of Memory Colour on Colour Constancy for Unknown Coloured Objects
Directory of Open Access Journals (Sweden)
Jeroen J M Granzier
2012-04-01
Full Text Available The perception of an object's colour remains constant despite large variations in the chromaticity of the illumination—colour constancy. Hering suggested that memory colours, the typical colours of objects, could help in estimating the illuminant's colour and therefore be an important factor in establishing colour constancy. Here we test whether the presence of objects with diagnostical colours (fruits, vegetables, etc within a scene influence colour constancy for unknown coloured objects in the scene. Subjects matched one of four Munsell papers placed in a scene illuminated under either a reddish or a greenish lamp with the Munsell book of colour illuminated by a neutral lamp. The Munsell papers were embedded in four different scenes—one scene containing diagnostically coloured objects, one scene containing incongruent coloured objects, a third scene with geometrical objects of the same colour as the diagnostically coloured objects, and one scene containing non-diagnostically coloured objects (eg, a yellow coffee mug. All objects were placed against a black background. Colour constancy was on average significantly higher for the scene containing the diagnostically coloured objects compared with the other scenes tested. We conclude that the colours of familiar objects help in obtaining colour constancy for unknown objects.
Effects of memory colour on colour constancy for unknown coloured objects
Granzier, Jeroen J M; Gegenfurtner, Karl R
2012-01-01
The perception of an object's colour remains constant despite large variations in the chromaticity of the illumination—colour constancy. Hering suggested that memory colours, the typical colours of objects, could help in estimating the illuminant's colour and therefore be an important factor in establishing colour constancy. Here we test whether the presence of objects with diagnostical colours (fruits, vegetables, etc) within a scene influence colour constancy for unknown coloured objects in the scene. Subjects matched one of four Munsell papers placed in a scene illuminated under either a reddish or a greenish lamp with the Munsell book of colour illuminated by a neutral lamp. The Munsell papers were embedded in four different scenes—one scene containing diagnostically coloured objects, one scene containing incongruent coloured objects, a third scene with geometrical objects of the same colour as the diagnostically coloured objects, and one scene containing non-diagnostically coloured objects (eg, a yellow coffee mug). All objects were placed against a black background. Colour constancy was on average significantly higher for the scene containing the diagnostically coloured objects compared with the other scenes tested. We conclude that the colours of familiar objects help in obtaining colour constancy for unknown objects. PMID:23145282
International Nuclear Information System (INIS)
Tysnes, O.B.; Aarbakke, G.M.; Verhoeven, A.J.; Holmsen, H.
1985-01-01
Different ratios of radioactive polyphosphoinositides in platelets pulse-labelled with 32p-orthophosphate have been reported by various laboratories. We studied whether these differences originate from differences in methodology. Extracts of 32p-Pi labelled human platelets were prepared at various times after gel-filtration and phosphatidylinositol (PI)-, mono (PIP)- and bisphosphate (PIP2) were separated by thin-layer chromatography using four different solvent systems. The 32p-levels in PIP and PIP2 remained constant during one hour after gel-filtration, whereas 32p-PI increased continuously and more than doubled within the first h. In two of the systems PIP co-chromatographed with a radioactive compound which separated well from PIP in the two other systems. This unknown compound was also labelled with 3H-glycerol, 3H-inositol and 3H-arachidonic acid, but it was metabolically and functionally different from the polyphosphoinositides. Both the co-chromatography of this unknown phospholipid and the increase in 32p-PI in gel-filtered platelets can explain the difference in 32p-labelling in phosphoinositides reported in the literature
Determination of stability constants using genetic algorithms
Hartnett, Margaret K.; Bos, M.; van der Linden, W.E.; Diamond, Dermot
1995-01-01
A genetic algorithm (GA)-simplex hybrid approach has been developed for the determination of stability constants using calorimetric and polarographic data obtained from literature sources. The GA determined both the most suitable equilibrium model for the systems studied and the values of the
Bounds on Gromov hyperbolicity constant in graphs
Indian Academy of Sciences (India)
Home; Journals; Proceedings – Mathematical Sciences; Volume 122; Issue 1. Bounds on Gromov Hyperbolicity Constant in Graphs. José M Rodríguez José M Sigarreta. Volume 122 ... Spain; Facultad de Matemáticas, Universidad Autónoma de Guerrero, Carlos E. Adame No. 54 Col. Garita, 39650 Acalpulco Gro., Mexico ...
Timelike Constant Mean Curvature Surfaces with Singularities
DEFF Research Database (Denmark)
Brander, David; Svensson, Martin
2014-01-01
We use integrable systems techniques to study the singularities of timelike non-minimal constant mean curvature (CMC) surfaces in the Lorentz–Minkowski 3-space. The singularities arise at the boundary of the Birkhoff big cell of the loop group involved. We examine the behavior of the surfaces...
Dissociative electron attachment to ozone: rate constant
International Nuclear Information System (INIS)
Skalny, J.D.; Cicman, P.; Maerk, T.D.
2002-01-01
The rate constant for dissociative electron attachment to ozone has been derived over the energy range of 0-10 eV by using previously measured cross section data revisited here in regards to discrimination effect occurring during the extraction of ions. The obtained data for both possible channels exhibit the maximum at mean electron energies close to 1 eV. (author)
Internal machining accomplished at constant radii
Gollihugh, T. E.
1966-01-01
Device machines fluid passages in workpieces at constant radii through two adjacent surfaces that are at included angles up to approximately 120 degrees. This technique has been used extensively in fabricating engine parts where close control of fluid flow is a requirement.
On the determination of the Hubble constant
International Nuclear Information System (INIS)
Gurzadyan, V.G.; Harutyunyan, V.V.; Kocharyan, A.A.
1990-10-01
The possibility of an alternative determination of the distance scale of the Universe and the Hubble constant based on the numerical analysis of the hierarchical nature of the large scale Universe (galaxies, clusters and superclusters) is proposed. The results of computer experiments performed by means of special numerical algorithms are represented. (author). 9 refs, 7 figs
On Product Logic with Truth-Constants
Czech Academy of Sciences Publication Activity Database
Savický, Petr; Cignoli, R.; Esteva, F.; Godo, L.; Noguera, C.
2006-01-01
Roč. 16, č. 2 (2006), s. 205-225 ISSN 0955-792X R&D Projects: GA MŠk 1M0545 Keywords : non-classical logic * fuzzy logic * product logic * truth-constants * standard completeness Subject RIV: BA - General Mathematics Impact factor: 0.840, year: 2006
The Nature of the Cosmological Constant Problem
Maia, M. D.; Capistrano, A. J. S.; Monte, E. M.
General relativity postulates the Minkowski space-time as the standard (flat) geometry against which we compare all curved space-times and also as the gravitational ground state where particles, quantum fields and their vacua are defined. On the other hand, experimental evidences tell that there exists a non-zero cosmological constant, which implies in a deSitter ground state, which not compatible with the assumed Minkowski structure. Such inconsistency is an evidence of the missing standard of curvature in Riemann's geometry, which in general relativity manifests itself in the form of the cosmological constant problem. We show how the lack of a curvature standard in Riemann's geometry can be fixed by Nash's theorem on metric perturbations. The resulting higher dimensional gravitational theory is more general than general relativity, similar to brane-world gravity, but where the propagation of the gravitational field along the extra dimensions is a mathematical necessity, rather than a postulate. After a brief introduction to Nash's theorem, we show that the vacuum energy density must remain confined to four-dimensional space-times, but the cosmological constant resulting from the contracted Bianchi identity represents a gravitational term which is not confined. In this case, the comparison between the vacuum energy and the cosmological constant in general relativity does not make sense. Instead, the geometrical fix provided by Nash's theorem suggests that the vacuum energy density contributes to the perturbations of the gravitational field.
Redundant internal coordinates, compliance constants and non ...
Indian Academy of Sciences (India)
Abstract. A long standing problem in normal mode analysis is identifying the right internal coordinates given only the cartesian coordinates, the masses of the atoms and the cartesian force constants without using any other additional chemical information. A possible solution is suggested here as drawing the normal modes.
Lifetime of titanium filament at constant current
International Nuclear Information System (INIS)
Chou, T.S.; Lanni, C.
1981-01-01
Titanium Sublimation Pump (TSP) represents the most efficient and the least expensive method to produce Ultra High Vacuum (UHV) in storage rings. In ISABELLE, a proton storage accelerator under construction at Brookhaven National Laboratory, for example, TSP provides a pumping speed for hydrogen of > 2 x 10 6 l/s. Due to the finite life of titanium filaments, new filaments have to be switched in before the end of filament burn out, to ensure smooth operation of the accelerator. Therefore, several operational modes that can be used to activate the TSP were studied. The constant current mode is a convenient way of maintaining constant evaporating rate by increasing the power input while the filament diameter decreases as titanium evaporates. The filaments used in this experiment were standard Varian 916-0024 filaments made of Ti 85%, Mo 15% alloy. During their lifetime at a constant current of 48 amperes, the evaporation rate rose to a maximum at about 10% of their life and then flattened out to a constant value, 0.25 g/hr. The maximum evaporation rate occurs coincidently with the recrystallization of 74% Ti 26% Mo 2 from microstructure crystalline at higher titanium concentration to macrostructure crystalline at lower titanium concentration. As the macrocrystal grows, the slip plane develops at the grain boundary resulting in high resistance at the slip plane which will eventually cause the filament burn out due to local heating
Simple atoms: QED tests and fundamental constants
International Nuclear Information System (INIS)
Karshenboim, S.G.
2002-01-01
Full text: Study of simple atoms can be performed theoretically and experimentally with a high accuracy and a comparison of theory and experiment provide us with several high precision tests of bound state QED. Theory cannot actually leads to a figure to compare with experiment, but it only can present some measurable quantities in terms of fundamental and auxiliary constants. That offers an opportunity to obtain new accurate values of some fundamental constants. Theory of simple atoms is based on Quantum electrodynamics but also involves an essential part of nuclear and particle physics. A significant part of experiments are related to high-resolution laser spectroscopy. Present status of the precision physics of simple atoms is presented in detail. We overview a comparison of the theory of such atoms, bound state QED, and the experiment. In particular, we consider the hyperfine structure in light atoms and the g-factor of a bound electron in hydrogen-like ions at low and medium Z. We discuss a project on optical measurement of of 2s hyperfine interval in atomic hydrogen. We also pay attention to determination of the fundamental constants from study of simple atoms. The constants under consideration includes alpha, electron-to-proton mass ratio and electron-to-muon mass ratio
The case for the cosmological constant
Indian Academy of Sciences (India)
The main motivation for invoking a small cosmological constant (orA-term) at the present epoch has to ... positive A-term leads to an increase in the luminosity distance and hence to a decline in the observed luminosity of high .... 0 leads to a longer age for the universe and could resolve the 'age problem' which has proved ...
PION-NUCLEON COUPLING-CONSTANT
STOKS,; TIMMERMANS, R; DESWART, JJ
In view of the persisting misunderstandings about the determination of the pion-nucleon coupling constants in the Nijmegen multienergy partial-wave analyses of pp, np, and ppBAR scattering data, we present additional information which may clarify several points of discussion. We comment on several
Time constant of logarithmic creep and relaxation
CSIR Research Space (South Africa)
Nabarro, FRN
2001-07-15
Full Text Available length and hardness which vary logarithmically with time. For dimensional reasons, a logarithmic variation must involve a time constant tau characteristic of the process, so that the deformation is proportional to ln(t/tau). Two distinct mechanisms...
Prevalence and Impact of Unknown Diabetes in the ICU.
Carpenter, David L; Gregg, Sara R; Xu, Kejun; Buchman, Timothy G; Coopersmith, Craig M
2015-12-01
Many patients with diabetes and their care providers are unaware of the presence of the disease. Dysglycemia encompassing hyperglycemia, hypoglycemia, and glucose variability is common in the ICU in patients with and without diabetes. The purpose of this study was to determine the impact of unknown diabetes on glycemic control in the ICU. Prospective observational study. Nine ICUs in an academic, tertiary hospital and a hybrid academic/community hospital. Hemoglobin A1c levels were ordered at all ICU admissions from March 1, 2011 to September 30, 2013. Electronic medical records were examined for a history of antihyperglycemic medications or International Classification of Diseases, 9th Edition diagnosis of diabetes. Patients were categorized as having unknown diabetes (hemoglobin A1c > 6.5%, without history of diabetes), no diabetes (hemoglobin A1c 6.5%, with documented history of diabetes). None. A total of 15,737 patients had an hemoglobin A1c and medical record evaluable for the history of diabetes, and 5,635 patients had diabetes diagnosed by either medical history or an elevated hemoglobin A1c in the ICU. Of these, 1,460 patients had unknown diabetes, accounting for 26.0% of all patients with diabetes. This represented 41.0% of patients with an hemoglobin A1c > 6.5% and 9.3% of all ICU patients. Compared with patients without diabetes, patients with unknown diabetes had a higher likelihood of requiring an insulin infusion (44.3% vs 29.3%; p 180 mg/dL; p < 0.0001) and hypoglycemia (8.9% vs 2.5%; blood glucose < 70 mg/dL; p < 0.0001), higher glycemic variability (55.6 vs 28.8, average of patient SD of glucose; p < 0.0001), and increased mortality (13.8% vs 11.4%; p = 0.01). Patients with unknown diabetes represent a significant percentage of ICU admissions. Measurement of hemoglobin A1c at admission can prospectively identify a population that are not known to have diabetes but have significant challenges in glycemic control in the ICU.
Construction of Lines of Constant Density and Constant Refractive Index for Ternary Liquid Mixtures.
Tasic, Aleksandar Z.; Djordjevic, Bojan D.
1983-01-01
Demonstrates construction of density constant and refractive index constant lines in triangular coordinate system on basis of systematic experimental determinations of density and refractive index for both homogeneous (single-phase) ternary liquid mixtures (of known composition) and the corresponding binary compositions. Background information,…
Núñez, M; Robie, T; Vlachos, D G
2017-10-28
Kinetic Monte Carlo (KMC) simulation provides insights into catalytic reactions unobtainable with either experiments or mean-field microkinetic models. Sensitivity analysis of KMC models assesses the robustness of the predictions to parametric perturbations and identifies rate determining steps in a chemical reaction network. Stiffness in the chemical reaction network, a ubiquitous feature, demands lengthy run times for KMC models and renders efficient sensitivity analysis based on the likelihood ratio method unusable. We address the challenge of efficiently conducting KMC simulations and performing accurate sensitivity analysis in systems with unknown time scales by employing two acceleration techniques: rate constant rescaling and parallel processing. We develop statistical criteria that ensure sufficient sampling of non-equilibrium steady state conditions. Our approach provides the twofold benefit of accelerating the simulation itself and enabling likelihood ratio sensitivity analysis, which provides further speedup relative to finite difference sensitivity analysis. As a result, the likelihood ratio method can be applied to real chemistry. We apply our methodology to the water-gas shift reaction on Pt(111).
Núñez, M.; Robie, T.; Vlachos, D. G.
2017-10-01
Kinetic Monte Carlo (KMC) simulation provides insights into catalytic reactions unobtainable with either experiments or mean-field microkinetic models. Sensitivity analysis of KMC models assesses the robustness of the predictions to parametric perturbations and identifies rate determining steps in a chemical reaction network. Stiffness in the chemical reaction network, a ubiquitous feature, demands lengthy run times for KMC models and renders efficient sensitivity analysis based on the likelihood ratio method unusable. We address the challenge of efficiently conducting KMC simulations and performing accurate sensitivity analysis in systems with unknown time scales by employing two acceleration techniques: rate constant rescaling and parallel processing. We develop statistical criteria that ensure sufficient sampling of non-equilibrium steady state conditions. Our approach provides the twofold benefit of accelerating the simulation itself and enabling likelihood ratio sensitivity analysis, which provides further speedup relative to finite difference sensitivity analysis. As a result, the likelihood ratio method can be applied to real chemistry. We apply our methodology to the water-gas shift reaction on Pt(111).
DEFF Research Database (Denmark)
Pawlowski, F; Jorgensen, P; Olsen, Jeppe
2002-01-01
A detailed study is carried out of the accuracy of molecular equilibrium geometries obtained from least-squares fits involving experimental rotational constants B(0) and sums of ab initio vibration-rotation interaction constants alpha(r)(B). The vibration-rotation interaction constants have been...... calculated for 18 single-configuration dominated molecules containing hydrogen and first-row atoms at various standard levels of ab initio theory. Comparisons with the experimental data and tests for the internal consistency of the calculations show that the equilibrium structures generated using Hartree......-Fock vibration-rotation interaction constants have an accuracy similar to that obtained by a direct minimization of the CCSD(T) energy. The most accurate vibration-rotation interaction constants are those calculated at the CCSD(T)/cc-pVQZ level. The equilibrium bond distances determined from these interaction...
Moral hypocrisy: addressing some alternatives.
Batson, C Daniel; Thompson, Elizabeth R; Chen, Hubert
2002-08-01
Two studies addressed alternative explanations for 3 pieces of evidence supporting the existence of moral hypocrisy. In Study 1, no support was found for the idea that low salience of social standards accounts for falsifying the result of a coin flip to assign oneself a more desirable task. In Study 2, no support was found for the idea that responses of those who honestly win the flip account for the higher ratings of morality of their action by participants who assign themselves the more desirable task after flipping the coin. Also, no support was found for the idea that responses of those who honestly win the flip account for the inability of personal moral responsibility measures to predict moral action. Instead, results of both studies provided additional evidence of moral hypocrisy.
Fault tolerant control of wind turbines using unknown input observers
DEFF Research Database (Denmark)
Odgaard, Peter Fogh; Stoustrup, Jakob
2012-01-01
This paper presents a scheme for accommodating faults in the rotor and generator speed sensors in a wind turbine. These measured values are important both for the wind turbine controller as well as the supervisory control of the wind turbine. The scheme is based on unknown input observers, which...... are also used to detect and isolate these faults. The scheme is tested on a known benchmark for FDI and FTC of wind turbines. Tests on this benchmark model show a clear potential of the proposed scheme....
Fast entanglement detection for unknown states of two spatial qutrits
International Nuclear Information System (INIS)
Lima, G.; Gomez, E. S.; Saavedra, C.; Vargas, A.; Vianna, R. O.
2010-01-01
We investigate the practicality of the method proposed by Maciel et al. [Phys. Rev. A. 80, 032325 (2009).] for detecting the entanglement of two spatial qutrits (three-dimensional quantum systems), which are encoded in the discrete transverse momentum of single photons transmitted through a multislit aperture. The method is based on the acquisition of partial information of the quantum state through projective measurements, and a data processing analysis done with semidefinite programs. This analysis relies on generating gradually an optimal entanglement witness operator, and numerical investigations have shown that it allows for the entanglement detection of unknown states with a cost much lower than full state tomography.
Modal Parameter Identification from Responses of General Unknown Random Inputs
DEFF Research Database (Denmark)
Ibrahim, S. R.; Asmussen, J. C.; Brincker, Rune
1996-01-01
Modal parameter identification from ambient responses due to a general unknown random inputs is investigated. Existing identification techniques which are based on assumptions of white noise and or stationary random inputs are utilized even though the inputs conditions are not satisfied....... This is accomplished via adding. In cascade. A force cascade conversion to the structures system under consideration. The input to the force conversion system is white noise and the output of which is the actual force(s) applied to the structure. The white noise input(s) and the structures responses are then used...
Maximum-revenue tariff under Bertrand duopoly with unknown costs
Ferreira, Fernanda A.; Ferreira, Flávio
2009-09-01
This paper considers an international trade under Bertrand model with differentiated products and with unknown production costs. The home government imposes a specific import tariff per unit of imports from the foreign firm. We prove that this tariff is decreasing in the expected production costs of the foreign firm and increasing in the production costs of the home firm. Furthermore, it is increasing in the degree of product substitutability. We also show that an increase in the tariff results in both firms increasing their prices, an increase in both expected sales and expected profits for the home firm, and a decrease in both expected sales and expected profits for the foreign firm.
Benjamin Constant. Libertad, democracia y pluralismo
Directory of Open Access Journals (Sweden)
Claudia Patricia Fonnegra Osorio
2015-01-01
Full Text Available A partir de un enfoque interpretativo, en este artículo se aborda por qué para Benjamin Constant la democracia solo puede darse en donde se presenta una relación necesaria entre la libertad entendida como defensa de los derechos individuales —libertad como independencia o negativa— y la libertad concebida como principio de la participación pública —libertad como autonomía o positiva—. Asimismo, se presenta la importancia que atribuye el autor a las tradiciones que dan vida a la configuración del universo cultural de un pueblo. Se concluye que en la obra de Constant se encuentra una clara defensa del Estado de derecho y del pluralismo, la cual puede iluminar la comprensión de los problemas políticos de la contemporaneidad.
Supersymmetric Dark Matter with a Cosmological Constant
Wells, J D
1998-01-01
Recent measurements of cosmological parameters from the microwave background radiation, type Ia supernovae, and the age of globular clusters help determine the relic matter density in the universe. It is first shown with mild cosmological assumptions that the relic matter density satisfies $\\Omega_M h^2 < 0.6$ independent of the cosmological constant and independent of the SNIa data. Including the SNIa data, the constraint becomes $\\Omega_M h^2 < 0.35$. This result is then applied to supersymmetric models motivated by generic features in supergravity mediated supersymmetry breaking. The result is an upper bound on gaugino masses within reach of the LHC and a 1.5 TeV lepton collider. Thus, cosmological considerations are beginning to limit the supersymmetric mass spectra in the experimentally verifiable range without recourse to finetuning arguments, and without assuming a zero cosmological constant.
Understanding fine structure constants and three generations
International Nuclear Information System (INIS)
Bennett, D.L.; Nielsen, H.B.
1988-02-01
We put forward a model inspired by random dynamics that relates the smallness of the gauge coupling constants to the number of generations being 'large'. The new element in the present version of our model is the appearance of a free parameter χ that is a measure of the (presumably relatively minor) importance of a term in the plaquette action proportional to the trace in the (1/6, 2, 3) representation of the Standard Model. Calling N gen the number of generations, the sets of allowed (N gen , χN gen )-pairs obtained by imposing the three measured coupling constant values of the Standard Model form three lines. In addition to finding that these lines cross at a single point (as needed for a consistent fit), the intersection occurs with surprising accuracy at the integer N gen = 3 (thereby predicting exactly three generations). It is also encouraging that the parameter χ turns out to be small and positive as expected. (orig.)
Parametrised Constants and Replication for Spatial Mobility
DEFF Research Database (Denmark)
Hüttel, Hans; Haagensen, Bjørn
2009-01-01
and the calculus of mobile ambients. Here, processes are located at sites and can migrate between them. In this paper we say that an encoding is local if it does not introduce extra migration. We first study this property for the distributed π-calculus where locations can be dynamically created. If the set...... of reachable sites is static an encoding exists, but we also show that parametrised constants can not be encoded in the full calculus. The locality requirement supplements widely accepted encoding criteria. It appears to be a natural property in spatial calculi where links and locations can fail. The versions...... of the distributed π-calculus with parametrised constants and replication are incomparable. On the other hand, we shall see that there exists a simple encoding of recursion in mobile ambients....
The cosmological constant and the pulsating universe.
Tangherlini, F. R.
1991-02-01
The author's recently described method for obtaining an upper bound for a recollapsing, closed universe with a positive cosmological constant is extended to obtain a lower bound for a negative Λ. The bounds are readily generalized to cosmologies of higher dimensions. As the radius of recollapse becomes infinite and the metric Minkowskian, the bounds shrink to zero. It is inferred that in a special relativistic theory, the cosmological term should vanish. A special relativistic proof of this is given based on requiring invariance under the "tilting" of the spacelike hypersurface. Some of the remaining problems and possible successes of the pulsating universe are also described. In the appendix, the well-known instability of the Einstein universe is briefly treated by the method used here to obtain bounds on the cosmological constant.
Benjamin Constant. Libertad, democracia y pluralismo
Directory of Open Access Journals (Sweden)
Claudia Patricia Fonnegra Osorio
2015-12-01
Full Text Available A partir de un enfoque interpretativo, en este artículo se aborda por qué para Benjamin Constant la democracia solo puede darse en donde se presenta una relación necesaria entre la libertad entendida como defensa de los derechos individuales -libertad como independencia o negativa- y la libertad concebida como principio de la participación pública -libertad como autonomía o positiva-. Asimismo, se presenta la importancia que atribuye el autor a las tradiciones que dan vida a la configuración del universo cultural de un pueblo. Se concluye que en la obra de Constant se encuentra una clara defensa del Estado de derecho y del pluralismo, la cual puede iluminar la comprensión de los problemas políticos de la contemporaneidad.
Constant force extensional rheometry of polymer solutions
DEFF Research Database (Denmark)
Szabo, Peter; McKinley, Gareth H.; Clasen, Christian
2012-01-01
We revisit the rapid stretching of a liquid filament under the action of a constant imposed tensile force, a problem which was first considered by Matta and Tytus [J. Non-Newton. Fluid Mech. 35 (1990) 215–229]. A liquid bridge formed from a viscous Newtonian fluid or from a dilute polymer solution...... is first established between two cylindrical disks. The upper disk is held fixed and may be connected to a force transducer while the lower cylinder falls due to gravity. By varying the mass of the falling cylinder and measuring its resulting acceleration, the viscoelastic nature of the elongating fluid...... filament can be probed. In particular, we show that with this constant force pull (CFP) technique it is possible to readily impose very large material strains and strain rates so that the maximum extensibility of the polymer molecules may be quantified. This unique characteristic of the experiment...
Bardeen-Cooper-Schrieffer universal constants generalized
International Nuclear Information System (INIS)
Hazaimeh, A.H.
1992-01-01
Weak- and moderate-coupling BCS superconductivity theory is shown to admit a more general T c formula, wherein T c approaches zero somewhat faster than with the familiar BCS T c -formula. This theory leads to a departure from the universal behavior of the gap-to-T c ratio and is consistent with some recent empirical values for exotic superconductors. This ratio is smaller than the universal BCS value of 3.53 in a way which is consistent with weak electron-boson coupling. Similarly, other universal constants related to specific heat and critical magnetic field are modified. In this dissertation, The author investigates the latter constants for weak-coupling and moderate-coupling and carry out detailed comparisons with experimental data for the cuprates and with the corresponding predictions of strong-coupling theory. This effort is to elucidate the nature of these superconductors with regards to coupling strength within an electron-boson mechanism
Energy Technology Data Exchange (ETDEWEB)
Motohashi, Hayato [Universidad de Valencia-CSIC, Instituto de Fisica Corpuscular (IFIC), Valencia (Spain); Starobinsky, Alexei A. [L.D. Landau Institute for Theoretical Physics, RAS, Moscow (Russian Federation); National Research University Higher School of Economics, Moscow (Russian Federation)
2017-08-15
The previously introduced class of two-parametric phenomenological inflationary models in general relativity in which the slow-roll assumption is replaced by the more general, constant-roll condition is generalized to the case of f(R) gravity. A simple constant-roll condition is defined in the original Jordan frame, and exact expressions for a scalaron potential in the Einstein frame, for a function f(R) (in the parametric form) and for inflationary dynamics are obtained. The region of the model parameters permitted by the latest observational constraints on the scalar spectral index and the tensor-to-scalar ratio of primordial metric perturbations generated during inflation is determined. (orig.)
Sample variance in the local measurements of the Hubble constant
Wu, Hao-Yi; Huterer, Dragan
2017-11-01
The current >3σ tension between the Hubble constant H0 measured from local distance indicators and from cosmic microwave background is one of the most highly debated issues in cosmology, as it possibly indicates new physics or unknown systematics. In this work, we explore whether this tension can be alleviated by the sample variance in the local measurements, which use a small fraction of the Hubble volume. We use a large-volume cosmological N-body simulation to model the local measurements and to quantify the variance due to local density fluctuations and sample selection. We explicitly take into account the inhomogeneous spatial distribution of type Ia supernovae. Despite the faithful modelling of the observations, our results confirm previous findings that sample variance in the local Hubble constant (H_0^loc) measurements is small; we find σ (H_0^loc)=0.31 {km s^{-1}Mpc^{-1}}, a nearly negligible fraction of the ˜6 km s-1Mpc-1 necessary to explain the difference between the local and global H0 measurements. While the H0 tension could in principle be explained by our local neighbourhood being a underdense region of radius ˜150 Mpc, the extreme required underdensity of such a void (δ ≃ -0.8) makes it very unlikely in a ΛCDM universe, and it also violates existing observational constraints. Therefore, sample variance in a ΛCDM universe cannot appreciably alleviate the tension in H0 measurements even after taking into account the inhomogeneous selection of type Ia supernovae.
Bounds on Gromov hyperbolicity constant in graphs
Indian Academy of Sciences (India)
is a topic of recent and increasing interest in graph theory; see, for instance [3–5, 8–10,. 15–17, 18–20, 22, 23, 25–27]. The theory ..... the Laplace matrix μ∗, we have δ(G) ≤ n(μ∗ − d0) μ∗ . Proof. ..... [27] Tourís E, Graphs and Gromov hyperbolicity of non-constant negatively curved surfaces,. J. Math. Anal. Appl. 380 (2011) ...
Simulated annealing with constant thermodynamic speed
International Nuclear Information System (INIS)
Salamon, P.; Ruppeiner, G.; Liao, L.; Pedersen, J.
1987-01-01
Arguments are presented to the effect that the optimal annealing schedule for simulated annealing proceeds with constant thermodynamic speed, i.e., with dT/dt = -(v T)/(ε-√C), where T is the temperature, ε- is the relaxation time, C ist the heat capacity, t is the time, and v is the thermodynamic speed. Experimental results consistent with this conjecture are presented from simulated annealing on graph partitioning problems. (orig.)
Electromagnetic corrections to pseudoscalar decay constants
Energy Technology Data Exchange (ETDEWEB)
Glaessle, Benjamin Simon
2017-03-06
First principles Lattice quantum chromodynamics (LQCD) calculations enable the determination of low energy hadronic amplitudes. Precision LQCD calculations with relative errors smaller than approximately 1% require the inclusion of electromagnetic effects. We demonstrate that including (quenched) quantum electrodynamics effects in the LQCD calculation effects the values obtained for pseudoscalar decay constants in the per mille range. The importance of systematic effects, including finite volume effects and the charge dependence of renormalization and improvement coefficients, is highlighted.
The cosmological constant and galaxy formation
International Nuclear Information System (INIS)
Durrer, R.; Straumann, N.
1990-01-01
We derive a restrictive upper bound for the cosmological constant from the requirement that the formation of galaxies in a cold dark matter scenario should be compatible with the present observational limits for possible anisotropies of the microwave background. If the total density parameter Ω (including the vacuum energy) is equal to the critical value (Ω = 1), we find for the contribution Ω V of the vacuum energy density the conservative bound Ω V <0.7. (author)
A Memorandum Report: Physical Constants of MCE
2016-08-01
the density and surface tension. In effect, this constant is a corrected molar volume = P = MS / = S / where P = Parachor M = molar volume ...Clapeyron equation Surface tension Viscosity Freezing point GA 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER...to the Figure will show. The volatility of the MCE was calculated from the calculated values of vapor pressure by the ideal gas law and the values
Emergent gravity in spaces of constant curvature
Energy Technology Data Exchange (ETDEWEB)
Alvarez, Orlando; Haddad, Matthew [Department of Physics, University of Miami,1320 Campo Sano Ave, Coral Gables, FL 33146 (United States)
2017-03-07
In physical theories where the energy (action) is localized near a submanifold of a constant curvature space, there is a universal expression for the energy (or the action). We derive a multipole expansion for the energy that has a finite number of terms, and depends on intrinsic geometric invariants of the submanifold and extrinsic invariants of the embedding of the submanifold. This is the second of a pair of articles in which we try to develop a theory of emergent gravity arising from the embedding of a submanifold into an ambient space equipped with a quantum field theory. Our theoretical method requires a generalization of a formula due to by Hermann Weyl. While the first paper discussed the framework in Euclidean (Minkowski) space, here we discuss how this framework generalizes to spaces of constant sectional curvature. We focus primarily on anti de Sitter space. We then discuss how such a theory can give rise to a cosmological constant and Planck mass that are within reasonable bounds of the experimental values.
Thermodynamic binding constants for gallium transferrin
Energy Technology Data Exchange (ETDEWEB)
Harris, W.R.; Pecoraro, V.L.
1983-01-18
Gallium-67 is widely used as an imaging agent for tumors and inflammatory abscesses. It is well stablished that Ga/sup 3 +/ travels through the circulatory system bound to the serum iron transport protein transferrin and that this protein binding is an essential step in tumor localization. However, there have been conflicting reports on the magnitude of the gallium-transferrin binding constants. Therefore, thermodynamic binding constants for gallium complexation at the two specific metal binding sites of human serum transferrin at pH 7.4 and 5 mM NaHCO/sub 3/ have been determined by UV difference spectroscopy. The conditional constants calculated for 27 mM NaHCO/sub 3/ are log K/sub 1/* = 20.3 and log K/sub 2/* = 19.3. These results are discussed in relation to the thermodynamics of transferrin binding of Fe/sup 3 +/ and to previous reports on gallium binding. The strength of transferrin complexation is also compared to that of a series of low molecular weight ligands by using calculated pM values (pM = -log (Ga(H/sub 2/O)/sub 6/)) to express the effective binding strength at pH 7.4.
Emergent gravity in spaces of constant curvature
Alvarez, Orlando; Haddad, Matthew
2017-03-01
In physical theories where the energy (action) is localized near a submanifold of a constant curvature space, there is a universal expression for the energy (or the action). We derive a multipole expansion for the energy that has a finite number of terms, and depends on intrinsic geometric invariants of the submanifold and extrinsic invariants of the embedding of the submanifold. This is the second of a pair of articles in which we try to develop a theory of emergent gravity arising from the embedding of a submanifold into an ambient space equipped with a quantum field theory. Our theoretical method requires a generalization of a formula due to by Hermann Weyl. While the first paper discussed the framework in Euclidean (Minkowski) space, here we discuss how this framework generalizes to spaces of constant sectional curvature. We focus primarily on anti de Sitter space. We then discuss how such a theory can give rise to a cosmological constant and Planck mass that are within reasonable bounds of the experimental values.
Constant load and constant volume response of municipal solid waste in simple shear.
Zekkos, Dimitrios; Fei, Xunchang
2017-05-01
Constant load and constant volume simple shear testing was conducted on relatively fresh municipal solid waste (MSW) from two landfills in the United States, one in Michigan and a second in Texas, at respective natural moisture content below field capacity. The results were assessed in terms of two failure strain criteria, at 10% and 30% shear strain, and two interpretations of effective friction angle. Overall, friction angle obtained assuming that the failure plane is horizontal and at 10% shear strain resulted in a conservative estimation of shear strength of MSW. Comparisons between constant volume and constant load simple shear testing results indicated significant differences in the shear response of MSW with the shear resistance in constant volume being lower than the shear resistance in constant load. The majority of specimens were nearly uncompacted during specimen preparation to reproduce the state of MSW in bioreactor landfills or in uncontrolled waste dumps. The specimens had identical percentage of waste. The results of these tests suggest the possibility of significantly lower shear strength of MSW in bioreactor landfills where waste is placed with low compaction effort and constant volume, i.e., "undrained", conditions may occur. Compacted MSW specimens resulted in shear strength parameters that are higher than uncompacted specimens and closer to values reported in the literature. However, the normalized undrained shear strength in simple shear for uncompacted and compacted MSW was still higher than the normalized undrained shear strength reported in the literature for clayey and silty soils. Copyright © 2016 Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
Andréa Dâmaso Bertoldi
2012-01-01
Full Text Available Background. To estimate the exposure to medicines with unknown fetal risk during pregnancy and to analyze the maternal characteristics associated with it. Methods. A questionnaire was administered to 4,189 mothers of children belonging to the 2004 Pelotas (Brazil birth cohort study about use of any medicine during gestation. We evaluated the associations between use of medicines with unknown fetal risk and the independent variables through logistic regression models. Unknown fetal risk was defined as medicines in which studies in animals have revealed adverse effects on the fetus, and no controlled studies in women, or studies in women and animals, are available. Results. Out of the 4,189 women, 52.5% used at least one medicine from unknown fetal risk. Use of these medicines was associated with white skin color, high schooling, high income, six or more antenatal care consultations, hospital admission during pregnancy, and morbidity during gestation. Conclusion. The use of unknown fetal risk medicines is high, suggesting that their use must be addressed with caution with the aim of restricting their use to cases in which the benefits are greater than the potential risks.
Thermal expansion and temperature variation of elastic constants of Li(H,D) and Na(H,D) systems
International Nuclear Information System (INIS)
Islam, A.K.M.A.; Hoque, M.T.
1994-11-01
An analysis of thermal expansion of Li(H,D) systems up to melting temperature has been performed using the theory of anharmonic lattice. The study has for the first time been extended to Na(H,D) systems where very little or no data are available. The calculated lattice constants of Li(H,D) systems show quite good agreement with experiment. The success of the present calculation with Li(H,D) and room temperature lattice constant data for Na(H,D) given an indication of the reliability of the computed lattice constants and thermal expansion coefficients for Na(H,D) systems. The study also allows us to predict the hitherto unknown lattice constants of Na(H,D) crystal at 0K. The temperature dependence of elastic constants for Li(H,D) systems has also been evaluated. Comparison with measurements shows the reliability of the present calculations. (author). 45 refs, 4 figs
A region addresses patient safety.
Feinstein, Karen Wolk; Grunden, Naida; Harrison, Edward I
2002-06-01
The Pittsburgh Regional Healthcare Initiative (PRHI) is a coalition of 35 hospitals, 4 major insurers, more than 30 major and small-business health care purchasers, dozens of corporate and civic leaders, organized labor, and partnerships with state and federal government all working together to deliver perfect patient care throughout Southwestern Pennsylvania. PRHI believes that in pursuing perfection, many of the challenges facing today's health care delivery system (eg, waste and error in the delivery of care, rising costs, frustration and shortage among clinicians and workers, financial distress, overcapacity, and lack of access to care) will be addressed. PRHI has identified patient safety (nosocomial infections and medication errors) and 5 clinical areas (obstetrics, orthopedic surgery, cardiac surgery, depression, and diabetes) as ideal starting points. In each of these areas of work, PRHI partners have assembled multifacility/multidisciplinary groups charged with defining perfection, establishing region-wide reporting systems, and devising and implementing recommended improvement strategies and interventions. Many design and conceptual elements of the PRHI strategy are adapted from the Toyota Production System and its Pittsburgh derivative, the Alcoa Business System. PRHI is in the proof-of-concept phase of development.
Addressing Semantic Geographic Information Systems
Directory of Open Access Journals (Sweden)
Salvatore F. Pileggi
2013-11-01
Full Text Available The progressive consolidation of information technologies on a large scale has been facilitating and progressively increasing the production, collection, and diffusion of geographic data, as well as facilitating the integration of a large amount of external information into geographic information systems (GIS. Traditional GIS is transforming into a consolidated information infrastructure. This consolidated infrastructure is affecting more and more aspects of internet computing and services. Most popular systems (such as social networks, GPS, and decision support systems involve complex GIS and significant amounts of information. As a web service, GIS is affected by exactly the same problems that affect the web as a whole. Therefore, next generation GIS solutions have to address further methodological and data engineering challenges in order to accommodate new applications’ extended requirements (in terms of scale, interoperability, and complexity. The conceptual and semantic modeling of GIS, as well as the integration of semantics into current GIS, provide highly expressive environments that are capable of meeting the needs and requirements of a wide range of applications.
Three-dimensional cinematography with control object of unknown shape.
Dapena, J; Harman, E A; Miller, J A
1982-01-01
A technique for reconstruction of three-dimensional (3D) motion which involves a simple filming procedure but allows the deduction of coordinates in large object volumes was developed. Internal camera parameters are calculated from measurements of the film images of two calibrated crosses while external camera parameters are calculated from the film images of points in a control object of unknown shape but at least one known length. The control object, which includes the volume in which the activity is to take place, is formed by a series of poles placed at unknown locations, each carrying two targets. From the internal and external camera parameters, and from locations of the images of point in the films of the two cameras, 3D coordinates of the point can be calculated. Root mean square errors of the three coordinates of points in a large object volume (5m x 5m x 1.5m) were 15 mm, 13 mm, 13 mm and 6 mm, and relative errors in lengths averaged 0.5%, 0.7% and 0.5%, respectively.
Unknown facets of Well-Known Scientists Series - Part II
Directory of Open Access Journals (Sweden)
V S Dixit
2016-01-01
Full Text Available 1st in the series of articles on “Unknown Facets of well-known Scientists” was about Sir Frederick Grant Banting, co-discoverer of Insulin, who also researched in Aviation and Diving Medicines, results of which brought extraordinary benefits for Flight crew during the World War II. The article was published in the previous issue of the Journal Unknown facets could be celebrated attributes, talents or otherwise, but it is necessary that we get to know fully about the “great mind". THIS ARTICLE IS ABOUT DR WERNER THEODOR OTTO FORSSMANN, A CARDIOLOGIST, WHO BECAME A UROLOGIST! Does the name Dr Forssmann ring a bell? He shared the 1956 Nobel Prize in Physiology or Medicine with “Andre Cournand and Dickinson Richards". The trio was awarded for their “discoveries concerning heart catheterization and pathological changes in the circulatory system". Dr Forssmann was nominated for performing an experiment in which he introduced a catheter into a vein of his arm, further passing it onward into his heart It was risky. This was in the year 1929. Subject of this article is the self-experimentation he carried out and what happened later.
Atmospheric turbulence profiling with unknown power spectral density
Helin, Tapio; Kindermann, Stefan; Lehtonen, Jonatan; Ramlau, Ronny
2018-04-01
Adaptive optics (AO) is a technology in modern ground-based optical telescopes to compensate for the wavefront distortions caused by atmospheric turbulence. One method that allows to retrieve information about the atmosphere from telescope data is so-called SLODAR, where the atmospheric turbulence profile is estimated based on correlation data of Shack–Hartmann wavefront measurements. This approach relies on a layered Kolmogorov turbulence model. In this article, we propose a novel extension of the SLODAR concept by including a general non-Kolmogorov turbulence layer close to the ground with an unknown power spectral density. We prove that the joint estimation problem of the turbulence profile above ground simultaneously with the unknown power spectral density at the ground is ill-posed and propose three numerical reconstruction methods. We demonstrate by numerical simulations that our methods lead to substantial improvements in the turbulence profile reconstruction compared to the standard SLODAR-type approach. Also, our methods can accurately locate local perturbations in non-Kolmogorov power spectral densities.
Reactive Path Planning Approach for Docking Robots in Unknown Environment
Directory of Open Access Journals (Sweden)
Peng Cui
2017-01-01
Full Text Available Autonomous robots need to be recharged and exchange information with the host through docking in the long-distance tasks. Therefore, feasible path is required in the docking process to guide the robot and adjust its pose. However, when there are unknown obstacles in the work area, it becomes difficult to determine the feasible path for docking. This paper presents a reactive path planning approach named Dubins-APF (DAPF to solve the path planning problem for docking in unknown environment with obstacles. In this proposed approach the Dubins curves are combined with the designed obstacle avoidance potential field to plan the feasible path. Firstly, an initial path is planned and followed according to the configurations of the robot and the docking station. Then when the followed path is evaluated to be infeasible, the intermediate configuration is calculated as well as the replanned path based on the obstacle avoidance potential field. The robot will be navigated to the docking station with proper pose eventually via the DAPF approach. The proposed DAPF approach is efficient and does not require the prior knowledge about the environment. Simulation results are given to validate the effectiveness and feasibility of the proposed approach.
Detecting unknown chemical clouds at distance with multispectral imagery
Favier, Sylvain; Alazarine, Aymeric; Verneau, Manon; Verollet, Romain; Blanchard, Sébastien
2017-05-01
In the past, chemical incidents or attacks have often involved mixtures of chemicals or fractional formulations of toxic compounds. Terrorist groups are also likely to generate new toxic chemical agents. These situations involve unknown compounds and thus may be undetectable using traditional methods. Indeed, standoff gas detection with infrared devices traditionally relies on the comparison between measured signal and a library of signals included in a database. Observing the gas absorption in infrared band III (LWIR 8-14 μm), our multispectral infrared camera is used to detect gas clouds up to a range of several kilometers, to provide identification of gas type and to follow the motion of the cloud in real time. The approach described in this paper develops an algorithm that enables the device to detect gas even if the measured signature is not in the database - a pattern-matching-free algorithm. This detection process has been evaluated in the laboratory and subjected to significant experimental feedback. The results are a capability to detect unknown gases and gas mixtures.
Atomic Clocks and Constraints on Variations of Fundamental Constants
Karshenboim, Savely G.; Flambaum, Victor; Peik, Ekkehard
2004-01-01
We consider an application of precision frequency measurements to searches for possible time variations of the fundamental physical constants. Current laboratory constraints on variations of the fine structure constant alpha and other fundamental constants are presented.
Exploring the Unknown: The Autonomy of Saudi EFL Learners
Alrabai, Fakieh
2017-01-01
This study addresses a new area of research in Saudi Arabia. Using a sample of 630 Saudi students, it investigates learners' level of autonomy and its relationship to academic achievement in English as a foreign language (EFL). Learners' level of autonomy was measured by a survey, whereas their achievement was evaluated using standardized…
Gait Control for Redundant Legged Biped Robot at Constant Velocity and Constant Height of the Waist
Shima, Ryoichi; Haishi, Masahiko; Shibata, Masaaki
In this paper, we propose a gait control method for redundant legged biped robot based on leg center of mass (COM) position control at constant velocity and constant height of the waist. The developed biped robot has redundant legs, which have 4 degree-of-freedoms (DOFs) on each in the saggital plane. The redundant DOF enables to move its leg tip position and its leg COM position independently. Therefore proposed robot has structural capability to control the leg COM position for keeping the projection of the total COM inside the support polygon without upper body motion. Such capability enables the stable static walk in the arbitrarily desired velocity and height of the waist motion. The validity of the proposed method for the static walk at constant velocity and constant height of the waist in the leg COM position control for redundant legged biped robot is confirmed by several results of simulation and experiment.
The Missing Measurements of the Gravitational Constant
Directory of Open Access Journals (Sweden)
Michelini M.
2009-07-01
Full Text Available G measurements are made with torsion balance in “vacuum” to the aim of eliminating the air convection distur- bances. Nevertheless, the accuracy of the measured values appears unsatisfying. In 2000 J. Luo and Z. K. Hu first denounced the presence of some unknown systematic error in high vacuum G measurements. In this work a new systematic effect is analyzed which arises in calm air from the non-zero balance of the overall momentum discharged by the air molecules on the test mass. This effect is negligible at vacuum pressures higher than a millibar. However in the interval between the millibar and the nanobar the disturbing force is not negligible and becomes comparable to the gravitational force when the chamber pressure drops to about 10E-5 bar. At the epoch of Heyl’s benchmark measurement at 1–2 millibar (1927, the technology of high vacuum pumps was developed, but this chance was not utilized without declaring the reason. The recent G measurements use high vacuum techniques up to 10 E-10 and 10 E-11 bar, but the effect of the air meatus is not always negligible. We wonder whether the measurements in the interval between the millibar and the nanobar have been made. As a matter of fact, we were not able to find the related papers in the literature. A physical explanation of the denounced unknown systematic error appears useful also in this respect.
The Missing Measurements of the Gravitational Constant
Directory of Open Access Journals (Sweden)
Michelini M.
2009-07-01
Full Text Available $G$ measurements are made with torsion balance in "vacuum" to the aim of eliminating the air convection disturbances. Nevertheless, the accuracy of the measured values appears unsatisfying. In 2000 J.Luo and Z.K.Hu first denounced the presence of some unknown systematic error in high vacuum $G$ measurements. In this work a new systematic effect is analyzed which arises in calm air from the non-zero balance of the overall momentum discharged by the air molecules on the test mass. This effect is negligible at vacuum pressures higher than a millibar. However in the interval between the millibar and the nanobar the disturbing force is not negligible and becomes comparable to the gravitational force when the chamber pressure drops to about $10^{-5}$ bar. At the epoch of Heyl's benchmark measurement at 1-2 millibar (1927, the technology of high vacuum pumps was developed, but this chance was not utilized without declaring the reason. The recent $G$ measurements use high vacuum techniques up to $10^{-10}$ and $10^{-11}$ bar, but the effect of the air meatus is not always negligible. We wonder whether the measurements in the interval between the millibar and the nanobar have been made. As a matter of fact, we were not able to find the related papers in the literature. A physical explanation of the denounced unknown systematic error appears useful also in this respect.
Constant load and constant displacement stress corrosion in simulated water reactor environments
International Nuclear Information System (INIS)
Lloyd, G.J.
1987-02-01
The stress corrosion behaviour of selected water reactor constructional materials, as determined by constant load or constant displacement test techniques, is reviewed. Experimental results obtained using a very wide range of conditions have been collected in a form for easy reference. A discussion is given of some apparent trends in these data. The possible reasons for these trends are considered together with a discussion of how the observed discrepancies may be resolved. (author)
PHYLOGENOMICS - GUIDED VALIDATION OF FUNCTION FOR CONSERVED UNKNOWN GENES
Energy Technology Data Exchange (ETDEWEB)
V, DE CRECY-LAGARD; D, HANSON A
2012-01-03
Identifying functions for all gene products in all sequenced organisms is a central challenge of the post-genomic era. However, at least 30-50% of the proteins encoded by any given genome are of unknown function, or wrongly or vaguely annotated. Many of these 'unknown' proteins are common to prokaryotes and plants. We accordingly set out to predict and experimentally test the functions of such proteins. Our approach to functional prediction is integrative, coupling the extensive post-genomic resources available for plants with comparative genomics based on hundreds of microbial genomes, and functional genomic datasets from model microorganisms. The early phase is computer-assisted; later phases incorporate intellectual input from expert plant and microbial biochemists. The approach thus bridges the gap between automated homology-based annotations and the classical gene discovery efforts of experimentalists, and is much more powerful than purely computational approaches to identifying gene-function associations. Among Arabidopsis genes, we focused on those (2,325 in total) that (i) are unique or belong to families with no more than three members, (ii) are conserved between plants and prokaryotes, and (iii) have unknown or poorly known functions. Computer-assisted selection of promising targets for deeper analysis was based on homology .. independent characteristics associated in the SEED database with the prokaryotic members of each family, specifically gene clustering and phyletic spread, as well as availability of functional genomics data, and publications that could link candidate families to general metabolic areas, or to specific functions. In-depth comparative genomic analysis was then performed for about 500 top candidate families, which connected ~55 of them to general areas of metabolism and led to specific functional predictions for a subset of ~25 more. Twenty predicted functions were experimentally tested in at least one prokaryotic organism
CONSTANT LEVERAGE AND CONSTANT COST OF CAPITAL: A COMMON KNOWLEDGE HALF-TRUTH
Directory of Open Access Journals (Sweden)
IGNACIO VÉLEZ-PAREJA
2008-01-01
Full Text Available Un enfoque típico para valorar flujos de caja finitos es suponer que el endeudamiento es constante (generalmente como un endeudamiento objetivo o deseado y que por tanto, el costo del patrimonio, Ke y el costo promedio ponderado de capital CPPC, también son constantes. Para los flujos de caja perpetuos, y con el costo de la deuda, Kd como la tasa de descuento para el ahorro en impuestos o escudo fiscal, Ke y el CPPC aplicado al flujo de caja libre FCL son constantes si el endeudamiento es constante. Sin embargo esto no es verdad para los flujos de caja finitos. En este documento mostramos que para flujos de caja finitos, Ke y por lo tanto el CPPC dependen de la tasa de descuento que se utiliza para valorar el ahorro en impuestos, AI y según lo esperado, Ke y el CPPC no son constantes con Kd como la tasa de descuento para el ahorro en impuestos, aunque el endeudamiento sea constante. Ilustramos esta situación con un ejemplo simple. Analizamos cinco métodos: el flujo de caja descontado, FCD, usando APV, el FCD y la formulación tradicional y general del CPPC, el valor presente del flujo de caja del accionista, FCA más deuda y el flujo de caja de capital, FCC.
Quantized cosmological constant in 1+1 dimensional quantum gravity with coupled scalar matter
Energy Technology Data Exchange (ETDEWEB)
Govaerts, Jan; Zonetti, Simone, E-mail: Jan.Govaerts@uclouvain.be, E-mail: Simone.Zonetti@uclouvain.be [Centre for Cosmology, Particle Physics and Phenomenology (CP3), Institut de Recherche en Mathematique et Physique (IRMP), Universite catholique de Louvain, Chemin du Cyclotron 2, B-1348 Louvain-la Neuve (Belgium)
2011-09-21
A two-dimensional matter-coupled model of quantum gravity is studied in the Dirac approach to constrained dynamics in the presence of a cosmological constant. It is shown that after partial fixing to the conformal gauge, the requirement of a quantum realization of the conformal algebra for physical quantum states of the fields naturally constrains the cosmological constant to take values in a well-determined and mostly discrete spectrum. Furthermore, the contribution of the quantum fluctuations of the single dynamical degree of freedom in the gravitational sector, namely the conformal mode, to the cosmological constant is negative, in contrast to the positive contributions of the quantum fluctuations of the matter fields, possibly opening an avenue towards addressing the cosmological constant problem in a more general context.
Chen, Xing; Rinkevicius, Zilvinas; Cao, Zexing; Ruud, Kenneth; Agren, Hans
2011-01-14
The present work addresses isotropic hyperfine coupling constants in polyatomic systems with a particular emphasis on a largely neglected, but a posteriori significant, effect, namely zero-point vibrational corrections. Using the density functional restricted-unrestricted approach, the zero-point vibrational corrections are evaluated for the allyl radical and four of its derivatives. In addition for establishing the numerical size of the zero-point vibrational corrections to the isotropic hyperfine coupling constants, we present simple guidelines useful for identifying hydrogens for which such corrections are significant. Based on our findings, we critically re-examine the computational procedures used for the determination of hyperfine coupling constants in general as well as the practice of using experimental hyperfine coupling constants as reference data when benchmarking and optimizing exchange-correlation functionals and basis sets for such calculations.
Zeh, Jeanne A; Bonilla, Melvin M; Su, Eleanor J; Padua, Michael V; Anderson, Rachel V; Zeh, David W
2014-01-15
Recent theory suggests that global warming may be catastrophic for tropical ectotherms. Although most studies addressing temperature effects in ectotherms utilize constant temperatures, Jensen's inequality and thermal stress considerations predict that this approach will underestimate warming effects on species experiencing daily temperature fluctuations in nature. Here, we tested this prediction in a neotropical pseudoscorpion. Nymphs were reared in control and high-temperature treatments under a constant daily temperature regime, and results compared to a companion fluctuating-temperature study. At constant temperature, pseudoscorpions outperformed their fluctuating-temperature counterparts. Individuals were larger, developed faster, and males produced more sperm, and females more embryos. The greatest impact of temperature regime involved short-term, adult exposure, with constant temperature mitigating high-temperature effects on reproductive traits. Our findings demonstrate the importance of realistic temperature regimes in climate warming studies, and suggest that exploitation of microhabitats that dampen temperature oscillations may be critical in avoiding extinction as tropical climates warm.
Directory of Open Access Journals (Sweden)
Kar-Weng Chan
2014-06-01
Full Text Available A recent concern of how to reliably establish the source level relationships of heroin case samples is addressed in this paper. Twenty-two trafficking heroin case samples of unknown origins seized from two major regions (Kuala Lumpur and Penang in Malaysia were studied. A procedure containing six major steps was followed to analyze and classify these samples. Subsequently, with the aid of statistical control samples, reliability of the clustering result was assessed. The final outcome reveals that the samples seized from the two regions in 2013 had highly likely originated from two different sources. Hence, the six-step procedure is sufficient for any chemist who attempts to assess the relative source level relationships of heroin samples.
Long, Lijun; Zhao, Jun
2017-07-01
In this paper, the problem of adaptive neural output-feedback control is addressed for a class of multi-input multioutput (MIMO) switched uncertain nonlinear systems with unknown control gains. Neural networks (NNs) are used to approximate unknown nonlinear functions. In order to avoid the conservativeness caused by adoption of a common observer for all subsystems, an MIMO NN switched observer is designed to estimate unmeasurable states. A new switched observer-based adaptive neural control technique for the problem studied is then provided by exploiting the classical average dwell time (ADT) method and the backstepping method and the Nussbaum gain technique. It effectively handles the obstacle about the coexistence of multiple Nussbaum-type function terms, and improves the classical ADT method, since the exponential decline property of Lyapunov functions for individual subsystems is no longer satisfied. It is shown that the technique proposed is able to guarantee semiglobal uniformly ultimately boundedness of all the signals in the closed-loop system under a class of switching signals with ADT, and the tracking errors converge to a small neighborhood of the origin. The effectiveness of the approach proposed is illustrated by its application to a two inverted pendulum system.
Identification of some unknown transcripts from SSH cDNA library of buffalo follicular oocytes.
Rajput, S K; Kumar, P; Roy, B; Verma, A; Pandey, H P; Singh, D; De, S; Datta, T K
2013-03-01
A buffalo oocyte-specific subtracted cDNA library was constructed to identify exclusively or preferentially oocyte-expressed genes. The library represented an enriched population of transcripts obtained from oocytes of diverse ovarian follicular origin and at different stages of in vitro maturation. A total of 1173 high-quality sequences of oocyte-specific genes were clustered into 645 unique sequences, out of which 65.76% were represented as singlets and 34.26% as contig expressed sequence tags (ESTs; clusters). Analysis of sequences revealed that 498 of these sequences were identified as a known sequence in mammalian species including buffalo, 103 as uncharacterized ESTs and 44 unknown sequences including 1 novel EST, so far not reported in any species. Gene ontology annotation classified these sequences into functional categories of cellular events and biological processes associated with oocyte competence. Expression status of the isolated unknown ESTs confirmed that many of these are expressed in oocytes exclusively and in others preferentially, some in excess of 80-fold greater in comparison with a variety of somatic tissues. The isolated novel EST was detected to be expressed exclusively in oocytes and testicular cells only. To our knowledge, this is the first report giving a detailed transcriptome account of oocyte-expressed genes in buffalo. This study will provide important information on the physiological control of oocyte development, as well as many questions yet to be addressed on the reproductive process of buffalo.
TASI Lectures on the cosmological constant
Energy Technology Data Exchange (ETDEWEB)
Bousso, Raphael; Bousso, Raphael
2007-08-30
The energy density of the vacuum, Lambda, is at least 60 orders of magnitude smaller than several known contributions to it. Approaches to this problem are tightly constrained by data ranging from elementary observations to precision experiments. Absent overwhelming evidence to the contrary, dark energy can only be interpreted as vacuum energy, so the venerable assumption that Lambda=0 conflicts with observation. The possibility remains that Lambda is fundamentally variable, though constant over large spacetime regions. This can explain the observed value, but only in a theory satisfying a number of restrictive kinematic and dynamical conditions. String theory offers a concrete realization through its landscape of metastable vacua.
Radiation balances and the solar constant
Crommelynck, D.
1981-01-01
The radiometric concepts are defined in order to consider various types of radiation balances and relate them to the diabetic form of the energy balance. Variability in space and time of the components of the radiation field are presented. A specific concept for sweeping which is tailored to the requirements is proposed. Finally, after establishing the truncated character of the present knowledge of the radiation balance. The results of the last observations of the solar constant are given. Ground and satellite measurement techniques are discussed.
Infrared propagator corrections for constant deceleration
Energy Technology Data Exchange (ETDEWEB)
Janssen, T M; Miao, S P; Prokopec, T [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, Leuvenlaan 4, Postbus 80.195, 3508 TD Utrecht (Netherlands); Woodard, R P [Department of Physics, University of Florida Gainesville, FL 32611 (United States)], E-mail: T.M.Janssen@uu.nl, E-mail: S.Miao@uu.nl, E-mail: T.Prokopec@uu.nl, E-mail: woodard@phys.ufl.edu
2008-12-21
We derive the propagator for a massless, minimally coupled scalar on a D-dimensional, spatially flat, homogeneous and isotropic background with arbitrary constant deceleration parameter. Our construction uses the operator formalism by integrating the Fourier mode sum. We give special attention to infrared corrections from the nonzero lower limit associated with working on finite spatial sections. These corrections eliminate infrared divergences that would otherwise be incorrectly treated by dimensional regularization, resulting in off-coincidence divergences for those special values of the deceleration parameter at which the infrared divergence is logarithmic. As an application we compute the expectation value of the scalar stress-energy tensor.
Measurements of hyperfine constants in Ca+
International Nuclear Information System (INIS)
Goble, A.T.; Maleki, S.
1990-01-01
We have measured the hyperfine constants A( 2 S 1/2 ), A( 2 P 1/2 ), and A( 2 P 3/2 ) for Ca + . We compare our results with the calculations of Martensson-Pendrill and Salomonson [Phys. Rev. A 30, 712 (1984)], who used many-body perturbation theory (MBPT). The agreement between our results and MBPT calculations for Ca + is about 3%, which is comparable to similar comparisons reported for Cs [S. Blundell, in 2 Relativistic, Quantum Electrodynamic, and Weak Interaction Effects in Atoms, AIP Conf. Proc. No. 189, edited by Walter Johnson, Peter Mohr, and Joseph Sucher (AIP, New York, 1988)
Rugged constant-temperature thermal anemometer.
Palma, J; Labbé, R
2016-12-01
Here we report a robust thermal anemometer which can be easily built. It was conceived to measure outdoor wind speeds and for airspeed monitoring in wind tunnels and other indoor uses. It works at a constant, low temperature of approximately 90 °C, so that an independent measurement of the air temperature is required to give a correct speed reading. Despite the size and high thermal inertia of the probe, the test results show that this anemometer is capable of measuring turbulent fluctuations up to ∼100 Hz in winds of ∼14 m/s, which corresponds to a scale similar to the length of the probe.
Autonomous Underwater Navigation and Optical Mapping in Unknown Natural Environments
Directory of Open Access Journals (Sweden)
Juan David Hernández
2016-07-01
Full Text Available We present an approach for navigating in unknown environments while, simultaneously, gathering information for inspecting underwater structures using an autonomous underwater vehicle (AUV. To accomplish this, we first use our pipeline for mapping and planning collision-free paths online, which endows an AUV with the capability to autonomously acquire optical data in close proximity. With that information, we then propose a reconstruction pipeline to create a photo-realistic textured 3D model of the inspected area. These 3D models are also of particular interest to other fields of study in marine sciences, since they can serve as base maps for environmental monitoring, thus allowing change detection of biological communities and their environment over time. Finally, we evaluate our approach using the Sparus II, a torpedo-shaped AUV, conducting inspection missions in a challenging, real-world and natural scenario.
Villitis of unknown aetiology: correlation of recurrence with clinical outcome.
LENUS (Irish Health Repository)
Feeley, L
2010-01-01
Villitis of unknown aetiology (VUA) is associated with adverse pregnancy outcome. Consequently, an ability to predict recurrence could be clinically relevant. We examined placentas where villitis was diagnosed in a previous pregnancy to establish the risk of recurrence and outcome. A total of 304 cases of VUA were diagnosed in our laboratory over a 4-year period. Subsequently, 19 of this cohort had a second placenta examined histologically. Recurrence and clinical outcome were recorded. Villitis recurred in 7 of 19 cases (37%). There was a high level of adverse pregnancy outcome in this cohort overall, characterised by small for gestational age infants and stillbirth, particularly in cases with high-grade villitis. We identified recurrent villitis more frequently than previously reported. Our findings confirm an association between high-grade villitis and poor outcome. Adequately powered prospective studies are required to determine if enhanced surveillance of subsequent pregnancies is indicated following a diagnosis of villitis.
Cancer of unknown primary origin: a case report
Directory of Open Access Journals (Sweden)
Elisa De Carlo
2013-03-01
Full Text Available Carcinoma of unknown primary origin (CUP accounts for 2-10% of all malignancies. The apparent absence of the primary tumour, the development of early, uncommon systemic metastases and the resistance to therapy and poor prognosis are hallmarks of this heterogeneous clinical entity and are a challenge for physicians. The diagnostic workup of patients with CUP includes a large amount of histopathological examination, as well as the use of imaging techniques that often fail to identify the primary tumour. Therefore, the optimal workup and treatment for these patients remains to be determined. Molecular diagnostic tools, such as DNA microarray analysis, could help in the search for "lost" CUP origin and guide the further treatment approach. We report the case of a 66-year-old man, with mediastinal lymph nodes metastasis of carcinoma and neurological syndrome with diplopia and balance disorders, in which many exams have been performed without finding the primary tumour.
A Brief Introduction on Mystery, the Unknown, Surprise
Directory of Open Access Journals (Sweden)
Sean Scanlan
2012-03-01
Full Text Available In this age of globalization, this age of so many ways to know—and so many ways to know things so quickly—it is both satisfying and deeply unnerving to come upon things and events that are really hard to understand, things and events so shocking or strange or mysterious, that they seem Unknown. Perhaps even unknowable. The first note of NANO Issue 2 focuses on an unsolved murder and reveals a mystery that is confounding, creepy, and yet oddly compelling. In “Karr’s Kill Cult: Virtual Cults and Pseudo-Killing in the Digital Age,” Jeremy Biles and Brian Collins explore the edges of where cyber-crime threatens to turn real—and vice versa. In the second note, Jennifer Ballengee compares Oedipus at Colonus with Don DeLillo’s Falling Man.
Distributed Synchronization Control of Multiagent Systems With Unknown Nonlinearities.
Su, Shize; Lin, Zongli; Garcia, Alfredo
2016-01-01
This paper revisits the distributed adaptive control problem for synchronization of multiagent systems where the dynamics of the agents are nonlinear, nonidentical, unknown, and subject to external disturbances. Two communication topologies, represented, respectively, by a fixed strongly-connected directed graph and by a switching connected undirected graph, are considered. Under both of these communication topologies, we use distributed neural networks to approximate the uncertain dynamics. Decentralized adaptive control protocols are then constructed to solve the cooperative tracker problem, the problem of synchronization of all follower agents to a leader agent. In particular, we show that, under the proposed decentralized control protocols, the synchronization errors are ultimately bounded, and their ultimate bounds can be reduced arbitrarily by choosing the control parameter appropriately. Simulation study verifies the effectiveness of our proposed protocols.
Chronic kidney disease of unknown etiology in agricultural communities.
Almaguer, Miguel; Herrera, Raúl; Orantes, Carlos M
2014-04-01
In recent years, Central America, Egypt, India and Sri Lanka have reported a high prevalence of chronic kidney disease of unknown etiology in agricultural communities, predominantly among male farmworkers. This essay examines the disease's case definitions, epidemiology (disease burden, demographics, associated risk factors) and causal hypotheses, by reviewing published findings from El Salvador, Nicaragua, Costa Rica, Sri Lanka, Egypt and India. The range of confirmed chronic kidney disease prevalence was 17.9%-21.1%. Prevalence of reduced glomerular filtration (homemade alcohol use and family history of chronic kidney disease. There is no strong evidence for a single cause, and multiple environmental, occupational and social factors are probably involved. Further etiological research is needed, plus interventions to reduce preventable risk factors.
Analysing Trust Transitivity and The Effects of Unknown Dependence
Directory of Open Access Journals (Sweden)
Touhid Bhuiyan
2010-03-01
Full Text Available Trust can be used to improve online automated recommendation within a given domain. Trust transitivity is used to make it successful. But trust transitivity has different interpretations. Trust and trust transitivity; both are the human mental phenomenon and for this reason, there is no such thing as objective transitivity. Trust transitivity and trust fusion both are important elements in computational trust. This paper analyses the parameter dependence problem in trust transitivity and proposes some definitions considering the effects of base rate. In addition, it also proposes belief functions based on subjective logic to analyse trust transitivity of three specified cases with sensitive and insensitive based rate. Then it presents a quantitative analysis of the effects of unknown dependence problem in an interconnected network environment; such Internet.
Obstacle Avoidance for Unmanned Undersea Vehicle in Unknown Unstructured Environment
Directory of Open Access Journals (Sweden)
Zheping Yan
2013-01-01
Full Text Available To avoid obstacle in the unknown environment for unmanned undersea vehicle (UUV, an obstacle avoiding system based on improved vector field histogram (VFH is designed. Forward looking sonar is used to detect the environment, and the divisional sonar modal is applied to deal with the measure uncertainty. To adapt to the VFH, rolling occupancy grids are used for the map building, and high accuracy details of local environment are obtained. The threshold is adaptively adjusted by the statistic of obstacles to solve the problem that VFH is sensitive to threshold. To improve the environment adaptability, the hybrid-behaviors strategy is proposed, which selects the optimal avoidance command according to the motion status and environment character. The simulation shows that UUV could avoid the obstacles fast and escape from the U shape obstacles.
Autonomous Underwater Navigation and Optical Mapping in Unknown Natural Environments
Hernández, Juan David; Istenič, Klemen; Gracias, Nuno; Palomeras, Narcís; Campos, Ricard; Vidal, Eduard; García, Rafael; Carreras, Marc
2016-01-01
We present an approach for navigating in unknown environments while, simultaneously, gathering information for inspecting underwater structures using an autonomous underwater vehicle (AUV). To accomplish this, we first use our pipeline for mapping and planning collision-free paths online, which endows an AUV with the capability to autonomously acquire optical data in close proximity. With that information, we then propose a reconstruction pipeline to create a photo-realistic textured 3D model of the inspected area. These 3D models are also of particular interest to other fields of study in marine sciences, since they can serve as base maps for environmental monitoring, thus allowing change detection of biological communities and their environment over time. Finally, we evaluate our approach using the Sparus II, a torpedo-shaped AUV, conducting inspection missions in a challenging, real-world and natural scenario. PMID:27472337
The Difficulty of Sexing Skeletons from Unknown Populations
Directory of Open Access Journals (Sweden)
Ingrid Sierp
2015-01-01
Full Text Available Determination of sex from skeletal remains is performed using a number of methods developed by biological anthropology. They must be evaluated for consistency and for their performance in a forensic setting. Twenty skeletons of varied provenance had their sex determined by 15 existing methods of forensic anthropology (7 metric and 8 morphological. The methods were evaluated for their consistency in determination of sex. No single individual was identified as belonging to one sex exclusively. Ambiguous results were obtained by metric methods for fourteen individuals (70% and by morphological methods for only five individuals (25% (Chi-squared = 4.3, df = 1, P<0.05. Methods which use the size of bones as an indicator of sex perform poorly on skeletal remains of individuals of unknown provenance. Methods which combine morphologic and metric techniques, that is, geometric morphometric analysis, may result in greater levels of consistency.
Distributed Multisensor Data Fusion under Unknown Correlation and Data Inconsistency
Directory of Open Access Journals (Sweden)
Muhammad Abu Bakr
2017-10-01
Full Text Available The paradigm of multisensor data fusion has been evolved from a centralized architecture to a decentralized or distributed architecture along with the advancement in sensor and communication technologies. These days, distributed state estimation and data fusion has been widely explored in diverse fields of engineering and control due to its superior performance over the centralized one in terms of flexibility, robustness to failure and cost effectiveness in infrastructure and communication. However, distributed multisensor data fusion is not without technical challenges to overcome: namely, dealing with cross-correlation and inconsistency among state estimates and sensor data. In this paper, we review the key theories and methodologies of distributed multisensor data fusion available to date with a specific focus on handling unknown correlation and data inconsistency. We aim at providing readers with a unifying view out of individual theories and methodologies by presenting a formal analysis of their implications. Finally, several directions of future research are highlighted.
Distributed Multisensor Data Fusion under Unknown Correlation and Data Inconsistency.
Bakr, Muhammad Abu; Lee, Sukhan
2017-10-27
The paradigm of multisensor data fusion has been evolved from a centralized architecture to a decentralized or distributed architecture along with the advancement in sensor and communication technologies. These days, distributed state estimation and data fusion has been widely explored in diverse fields of engineering and control due to its superior performance over the centralized one in terms of flexibility, robustness to failure and cost effectiveness in infrastructure and communication. However, distributed multisensor data fusion is not without technical challenges to overcome: namely, dealing with cross-correlation and inconsistency among state estimates and sensor data. In this paper, we review the key theories and methodologies of distributed multisensor data fusion available to date with a specific focus on handling unknown correlation and data inconsistency. We aim at providing readers with a unifying view out of individual theories and methodologies by presenting a formal analysis of their implications. Finally, several directions of future research are highlighted.
Impact of CT in patients with sepsis of unknown origin
International Nuclear Information System (INIS)
Barkhausen, J.; Stoeblen, F.; Mueller, R.D.
1999-01-01
Purpose: To evaluate the diagnostic relevance of CT in patients with sepsis of unknown origin. Material and Methods: Sixty-three consecutive intensive care patients with suspicion of an abscess and negative or inconclusive previous radiological examinations were included. CT was performed using the helical technique. A total of 45 abdominal and 38 chest examinations were evaluated. Results: 5/38 examinations of the chest revealed the source of sepsis (pleural empyema 2, lung abscess 1, mediastinitis 1, retrosternal abscess 1). 7/45 abdominal CT examinations showed the source of sepsis (intraabdominal abscess 2, hepatic abscess 3, intestinal perforation 1, gangrenous colitis 1). Conclusion: CT is useful for the evaluation of patients with fever or sepsis without a known source. Due to the detection of a spetic focus by CT, 19% of the patients in our study could be immediately referred to causal therapy as percutaneous drainage or surgery. (orig.)
Lichen Scrofulosorum Presenting as Pyrexia of Unknown Origin
International Nuclear Information System (INIS)
Patra, S.; Patro, B.; Patel, R.; Aneja, S.; Sarkar, D.
2014-01-01
Cutaneous tuberculosis forms a subset of extra pulmonary tuberculosis. It accounts for about 1.5% of all the cases of extrapulmonary tuberculosis. Lichen Scrofulosorum is a rare form of cutaneous tuberculosis. It is usually seen in children or young adults and an important marker of occult tuberculosis. Usually, the eruption appears in children and adolescents with strong immune sensitivity to Mycobacterium tuberculosis and consists of tiny follicular papules. Underlying systemic involvement is more common in children, compared with adults. We report a case of 3 years old boy who was investigated for pyrexia of unknown origin and finally diagnosed as Lichen Scrofulosorum associated with tuberculous lymphadenitis of mediastinal lymph nodes. A skin biopsy showed extensive tuberculoid granulomas surrounding hair follicles which were consistent with the diagnosis of Lichen Scrofulosorum. The child was treated with antitubercular drugs and it showed improvement within 2 weeks of starting treatment with resolution of skin lesions. (author)
Fever of unknown origin - Hidden in the head
Directory of Open Access Journals (Sweden)
Kamal Kishore Pandita
2015-07-01
Full Text Available The original algorithmic approach, as outlined by de Kleijn and colleagues and practiced commonly, envisages performing computed tomography (CT of chest, abdomen, and pelvis in patients with classical fever of unknown origin (FUO, in whom no potentially diagnostic clue exists. It further envisages performing positron emission tomography (PET scan, if CT scan is unrevealing. Imaging of head and neck especially magnetic resonance imaging (MRI has not been included in this algorithm, that leaves these important regions unexplored in most settings where PET scan is unavailable. MRI is a safe modality for evaluating central nervous system lesions and its role in FUO has not been adequately evaluated. We present three patients of FUO in whom the diagnosis of tuberculoma of brain as a cause of prolonged pyrexia got delayed because the MRI of head was not done initially, to comply with the approach of minimum diagnostic evaluation.
Designing low cost autonomous robots in unknown environments
Alouani, Ali T.; Sri, Aravind M.
2008-04-01
This paper documents the design and development of a low cost robot capable of autonomous navigation in unknown indoor environments. The proposed design uses only two complementary rotating sensors for navigation. The use of real time mapping allows for detection and avoidance of obstacles. The fusion of the sensors data helped improve accuracy of the online map of the robot environment. The robot builds an online map of its environment, and then automatically plans its navigation path. The feedback control keeps the robot moving along its planned path. The robot has been successfully tested in a cluttered environment in the Advanced Systems Lab. Preliminary tests carried out have shown the success of the robot in navigating autonomously.
Realization and Addressing Analysis In Blockchain Bitcoin
Sakti Arief Daulay, Raja; Michrandi Nasution, Surya; Paryasto, Marisa W.
2017-11-01
The implementation research and analyze address blockchain on this bitcoin will have the results that refers to making address bitcoin a safe and boost security of address the bitcoin. The working mechanism of blockchain in making address bitcoin which is already in the blockchain system.
Smooth extrapolation of unknown anatomy via statistical shape models
Grupp, R. B.; Chiang, H.; Otake, Y.; Murphy, R. J.; Gordon, C. R.; Armand, M.; Taylor, R. H.
2015-03-01
Several methods to perform extrapolation of unknown anatomy were evaluated. The primary application is to enhance surgical procedures that may use partial medical images or medical images of incomplete anatomy. Le Fort-based, face-jaw-teeth transplant is one such procedure. From CT data of 36 skulls and 21 mandibles separate Statistical Shape Models of the anatomical surfaces were created. Using the Statistical Shape Models, incomplete surfaces were projected to obtain complete surface estimates. The surface estimates exhibit non-zero error in regions where the true surface is known; it is desirable to keep the true surface and seamlessly merge the estimated unknown surface. Existing extrapolation techniques produce non-smooth transitions from the true surface to the estimated surface, resulting in additional error and a less aesthetically pleasing result. The three extrapolation techniques evaluated were: copying and pasting of the surface estimate (non-smooth baseline), a feathering between the patient surface and surface estimate, and an estimate generated via a Thin Plate Spline trained from displacements between the surface estimate and corresponding vertices of the known patient surface. Feathering and Thin Plate Spline approaches both yielded smooth transitions. However, feathering corrupted known vertex values. Leave-one-out analyses were conducted, with 5% to 50% of known anatomy removed from the left-out patient and estimated via the proposed approaches. The Thin Plate Spline approach yielded smaller errors than the other two approaches, with an average vertex error improvement of 1.46 mm and 1.38 mm for the skull and mandible respectively, over the baseline approach.
Identification of unknown sample using NAA, EDXRF, XRD techniques
International Nuclear Information System (INIS)
Dalvi, Aditi A.; Swain, K.K.; Chavan, Trupti; Remya Devi, P.S.; Wagh, D.N.; Verma, R.
2015-01-01
Analytical Chemistry Division (ACD), Bhabha Atomic Research Centre (BARC) receives samples from law enforcement agencies such as Directorate of Revenue Intelligence, Customs for analysis. Five unknown grey powdered samples were received for identification and were suspected to be Iridium (Ir). Identification of unknown sample is always a challenging task and suitable analytical techniques have to be judiciously utilized for arriving at the conclusion. Qualitative analysis was carried out using Jordan Valley, EX-3600 M Energy dispersive X-ray fluorescence (EDXRF) spectrometer at ACD, BARC. A SLP series LEO Si (Li) detector (active area: 30 mm 2 ; thickness: 3.5 mm; resolution: 140 eV at 5.9 keV of Mn K X-ray) was used during the measurement and only characteristic X-rays of Ir (Lα: 9.17 keV and Lβ: 10.70 keV) was seen in the X-ray spectrum. X-ray diffraction (XRD) measurement results indicated that the Ir was in the form of metal. To confirm the XRD data, neutron activation analysis (NAA) was carried out by irradiating samples and elemental standards (as comparator) in graphite reflector position of Advanced Heavy Water Reactor Critical Facility (AHWR CF) reactor, BARC, Mumbai. After suitable decay period, gamma activity measurements were carried out using 45% HPGe detector coupled to 8 k multi channel analyzer. Characteristic gamma line at 328.4 keV of the activation product 194 Ir was used for quantification of iridium and relative method of NAA was used for concentration calculations. NAA results confirmed that all the samples were Iridium metal. (author)
Holographic dark energy with cosmological constant
Energy Technology Data Exchange (ETDEWEB)
Hu, Yazhou; Li, Nan; Zhang, Zhenhui [State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190 (China); Li, Miao, E-mail: asiahu@itp.ac.cn, E-mail: mli@itp.ac.cn, E-mail: linan@itp.ac.cn, E-mail: zhangzhh@mail.ustc.edu.cn [School of Astronomy and Space Science, Sun Yat-Sen University, Guangzhou 510275 (China)
2015-08-01
Inspired by the multiverse scenario, we study a heterotic dark energy model in which there are two parts, the first being the cosmological constant and the second being the holographic dark energy, thus this model is named the ΛHDE model. By studying the ΛHDE model theoretically, we find that the parameters d and Ω{sub hde} are divided into a few domains in which the fate of the universe is quite different. We investigate dynamical behaviors of this model, and especially the future evolution of the universe. We perform fitting analysis on the cosmological parameters in the ΛHDE model by using the recent observational data. We find the model yields χ{sup 2}{sub min}=426.27 when constrained by Planck+SNLS3+BAO+HST, comparable to the results of the HDE model (428.20) and the concordant ΛCDM model (431.35). At 68.3% CL, we obtain −0.07<Ω{sub Λ0}<0.68 and correspondingly 0.04<Ω{sub hde0}<0.79, implying at present there is considerable degeneracy between the holographic dark energy and cosmological constant components in the ΛHDE model.
Ventricular fibrillation time constant for swine
International Nuclear Information System (INIS)
Wu, Jiun-Yan; Sun, Hongyu; Nimunkar, Amit J; Webster, John G; O'Rourke, Ann; Huebner, Shane; Will, James A
2008-01-01
The strength–duration curve for cardiac excitation can be modeled by a parallel resistor–capacitor circuit that has a time constant. Experiments on six pigs were performed by delivering current from the X26 Taser dart at a distance from the heart to cause ventricular fibrillation (VF). The X26 Taser is an electromuscular incapacitation device (EMD), which generates about 50 kV and delivers a pulse train of about 15–19 pulses s −1 with a pulse duration of about 150 µs and peak current about 2 A. Similarly a continuous 60 Hz alternating current of the amplitude required to cause VF was delivered from the same distance. The average current and duration of the current pulse were estimated in both sets of experiments. The strength–duration equation was solved to yield an average time constant of 2.87 ms ± 1.90 (SD). Results obtained may help in the development of safety standards for future electromuscular incapacitation devices (EMDs) without requiring additional animal tests
A Constant-Force Resistive Exercise Unit
Colosky, Paul; Ruttley, Tara
2010-01-01
A constant-force resistive exercise unit (CFREU) has been invented for use in both normal gravitational and microgravitational environments. In comparison with a typical conventional exercise machine, this CFREU weighs less and is less bulky: Whereas weight plates and associated bulky supporting structures are used to generate resistive forces in typical conventional exercise machines, they are not used in this CFREU. Instead, resistive forces are generated in this CFREU by relatively compact, lightweight mechanisms based on constant-torque springs wound on drums. Each such mechanism is contained in a module, denoted a resistive pack, that includes a shaft for making a torque connection to a cable drum. During a stroke of resistive exercise, the cable is withdrawn from the cable drum against the torque exerted by the resistance pack. The CFREU includes a housing, within which can be mounted one or more resistive pack(s). The CFREU also includes mechanisms for engaging any combination of (1) one or more resistive pack(s) and (2) one or more spring(s) within each resistive pack to obtain a desired level of resistance.
Is cosmological constant needed in Higgs inflation?
Directory of Open Access Journals (Sweden)
Chao-Jun Feng
2014-11-01
Full Text Available The detection of B-mode shows a very powerful constraint to theoretical inflation models through the measurement of the tensor-to-scalar ratio r. Higgs boson is the most likely candidate of the inflaton field. But usually, Higgs inflation models predict a small value of r, which is not quite consistent with the recent results from BICEP2. In this paper, we explored whether a cosmological constant energy component is needed to improve the situation. And we found the answer is yes. For the so-called Higgs chaotic inflation model with a quadratic potential, it predicts r≈0.2, ns≈0.96 with e-folds number N≈56, which is large enough to overcome the problems such as the horizon problem in the Big Bang cosmology. The required energy scale of the cosmological constant is roughly Λ∼(1014 GeV2, which means a mechanism is still needed to solve the fine-tuning problem in the later time evolution of the universe, e.g. by introducing some dark energy component.
Positive Cosmological Constant and Quantum Theory
Directory of Open Access Journals (Sweden)
Felix M. Lev
2010-11-01
Full Text Available We argue that quantum theory should proceed not from a spacetime background but from a Lie algebra, which is treated as a symmetry algebra. Then the fact that the cosmological constant is positive means not that the spacetime background is curved but that the de Sitter (dS algebra as the symmetry algebra is more relevant than the Poincare or anti de Sitter ones. The physical interpretation of irreducible representations (IRs of the dS algebra is considerably different from that for the other two algebras. One IR of the dS algebra splits into independent IRs for a particle and its antiparticle only when Poincare approximation works with a high accuracy. Only in this case additive quantum numbers such as electric, baryon and lepton charges are conserved, while at early stages of the Universe they could not be conserved. Another property of IRs of the dS algebra is that only fermions can be elementary and there can be no neutral elementary particles. The cosmological repulsion is a simple kinematical consequence of dS symmetry on quantum level when quasiclassical approximation is valid. Therefore the cosmological constant problem does not exist and there is no need to involve dark energy or other fields for explaining this phenomenon (in agreement with a similar conclusion by Bianchi and Rovelli.
Local Pain Dynamics during Constant Exhaustive Exercise.
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Agne Slapsinskaite
Full Text Available The purpose of this study was to delineate the topological dynamics of pain and discomfort during constant exercise performed until volitional exhaustion. Eleven physical education students were tested while cycling and running at a "hard" intensity level (e.g., corresponding to Borg's RPE (6-20 = 15. During the tests, participants reported their discomfort and pain on a body map every 15s. "Time on task" for each participant was divided into five equal non-overlapping temporal windows within which their ratings were considered for analysis. The analyses revealed that the number of body locations with perceived pain and discomfort increased throughout the five temporal windows until reaching the mean (± SE values of 4.2 ± 0.7 and 4.1 ± 0.6 in cycling and running, respectively. The dominant locations included the quadriceps and hamstrings during cycling and quadriceps and chest during running. In conclusion, pain seemed to spread throughout the body during constant cycling and running performed up to volitional exhaustion with differences between cycling and running in the upper body but not in the lower body dynamics.
Lepton Collider Operation with Constant Currents
Wienands, Ulrich
2005-01-01
Traditionally, electron-positron colliders have been operating in a top-off-and-coast fashion with a cycle time depending on the beam life time, typically on the order of an hour. Each top-off involves ramping detector systems in addition to the actual filling time. The loss in accumulated luminosity is typically 20-50%. During the last year, both B-Factories have commissioned a continuous-injection mode of operation in which beam is injected without ramping the detector, thus raising luminosity integration by constant operation at peak luminosity. Constant beam currents reduce thermal drift and trips caused by change in beam loading. To achieve this level of operation, special efforts were made to reduce the injection losses and also to implement special gating procedures in the detectors, minimizing dead time. Bunch-injection control decides which bunch to inject into next while maintaining small charge variation between bunches. Beam collimation can reduce injection noise but also cause an increase in back...
Holographic dark energy with cosmological constant
International Nuclear Information System (INIS)
Hu, Yazhou; Li, Nan; Zhang, Zhenhui; Li, Miao
2015-01-01
Inspired by the multiverse scenario, we study a heterotic dark energy model in which there are two parts, the first being the cosmological constant and the second being the holographic dark energy, thus this model is named the ΛHDE model. By studying the ΛHDE model theoretically, we find that the parameters d and Ω hde are divided into a few domains in which the fate of the universe is quite different. We investigate dynamical behaviors of this model, and especially the future evolution of the universe. We perform fitting analysis on the cosmological parameters in the ΛHDE model by using the recent observational data. We find the model yields χ 2 min =426.27 when constrained by Planck+SNLS3+BAO+HST, comparable to the results of the HDE model (428.20) and the concordant ΛCDM model (431.35). At 68.3% CL, we obtain −0.07<Ω Λ0 <0.68 and correspondingly 0.04<Ω hde0 <0.79, implying at present there is considerable degeneracy between the holographic dark energy and cosmological constant components in the ΛHDE model
The constant composition method for crystallization of calcium carbonate at constant supersaturation
Beck, R.; Seiersten, M.; Andreassen, J.-P.
2013-10-01
The exact control of supersaturation is of great importance when studying the formation of crystalline and amorphous matter. The constant composition method is suitable for the study of crystallization processes at constant supersaturation by controlled addition of titrants to a crystallizer to maintain constant pH. Not all aspects necessary for successful operation of this method are obvious from the existing literature, and the method is often used in an incorrect way. The focus of the present work is to highlight pitfalls associated with the constant composition method. The method is assessed and described in detail to show that even if the solution pH is kept constant, the supersaturation may change. First and foremost, it is illustrated how crucial it is to use a chemical composition of the titrant solutions which is in accordance with the initially prepared aqueous solution. General rules are presented for carbonates as to how the composition of the titrant solutions should be calculated based on total alkalinity in order to maintain constant supersaturation. This has - to the knowledge of the authors - not been shown before. Then, it is shown how exchange of carbon dioxide with the atmosphere corrupts the constancy of the supersaturation level during an experiment. Third, it is pointed out that the ionic strength should be kept constant throughout crystallization experiments since a change in ionic strength alters the activity of the ions in solution. Here, the determination of the thermodynamic driving force (supersaturation) is explained based on the relevant chemical equilibria, total alkalinity and calculation of the activity coefficients. The calculations are presented for the least stable polymorph of calcium carbonate, vaterite, but can easily be extended to the other polymorphs and other pH-dependent systems allowing for crystallization studies at low and maintained supersaturation levels typical of naturally occurring processes in geology and
Streamlined structure elucidation of an unknown compound in a pigment formulation.
Yüce, Imanuel; Morlock, Gertrud E
2016-10-21
A fast and reliable quality control is important for ink manufacturers to ensure a constant production grade of mixtures and chemical formulations, and unknown components attract their attention. Structure elucidating techniques seem time-consuming in combination with column-based methods, but especially the low solubility of pigment formulations is challenging the analysis. In contrast, layer chromatography is more tolerant with regard to pigment particles. One PLC plate for NMR and FTIR analyses and one HPTLC plate for recording of high resolution mass spectra, MS/MS spectra and for gathering information on polarity and spectral properties were needed to characterize a structure, exemplarily shown for an unknown component in pigment Red 57:1 to be 3-hydroxy-2-naphtoic acid. A preparative layer chromatography (PLC) workflow was developed that used an Automated Multiple Development 2 (AMD 2) system. The 0.5-mm PLC plate could still be operated in the AMD 2 system and allowed a smooth switch from the analytical to the preparative gradient separation. Through automated gradient development and the resulting focusing of bands, the sharpness of the PLC bands was improved. For NMR, the necessary high load of the target compound on the PLC plate was achieved via a selective solvent extraction that discriminated the polar sample matrix and thus increased the application volume of the extract that could maximally be applied without overloading. By doing so, the yield for NMR analysis was improved by a factor of 9. The effectivity gain through a simple, but thoroughly chosen extraction solvent is often overlooked, and for educational purpose, it was clearly illustrated and demonstrated by an extended solvent screening. Thus, PLC using an automated gradient development after a selective extraction was proven to be a new powerful combination for structural elucidation by NMR. Copyright © 2016 Elsevier B.V. All rights reserved.
Content-addressable read/write memories for image analysis
Snyder, W. E.; Savage, C. D.
1982-01-01
The commonly encountered image analysis problems of region labeling and clustering are found to be cases of search-and-rename problem which can be solved in parallel by a system architecture that is inherently suitable for VLSI implementation. This architecture is a novel form of content-addressable memory (CAM) which provides parallel search and update functions, allowing speed reductions down to constant time per operation. It has been proposed in related investigations by Hall (1981) that, with VLSI, CAM-based structures with enhanced instruction sets for general purpose processing will be feasible.
Directory of Open Access Journals (Sweden)
Chris Yoo
2017-12-01
Full Text Available Genomic data is estimated to be doubling every seven months with over 2 trillion bases from whole genome sequence studies deposited in Genbank in just the last 15 years alone. Recent advances in compute and storage have enabled the use of artificial intelligence techniques in areas such as feature recognition in digital pathology and chemical synthesis for drug development. To apply A.I. productively to multidimensional data such as cellular processes and their dysregulation, the data must be transformed into a structured format, using prior knowledge to create contextual relationships and hierarchies upon which computational analysis can be performed. Here we present the organization of complex data into hypergraphs that facilitate the application of A.I. We provide an example use case of a hypergraph containing hundreds of biological data values and the results of several classes of A.I. algorithms applied in a popular compute cloud. While multiple, biologically insightful correlations between disease states, behavior, and molecular features were identified, the insights of scientific import were revealed only when exploration of the data included visualization of subgraphs of represented knowledge. The results suggest that while machine learning can identify known correlations and suggest testable ones, the greater probability of discovering unexpected relationships between seemingly independent variables (unknown-unknowns requires a context-aware system – hypergraphs that impart biological meaning in nodes and edges. We discuss the implications of a combined hypergraph-A.I. analysis approach to multidimensional data and the pre-processing requirements for such a system.
Search for a Variation of Fundamental Constants
Ubachs, W.
2013-06-01
Since the days of Dirac scientists have speculated about the possibility that the laws of nature, and the fundamental constants appearing in those laws, are not rock-solid and eternal but may be subject to change in time or space. Such a scenario of evolving constants might provide an answer to the deepest puzzle of contemporary science, namely why the conditions in our local Universe allow for extreme complexity: the fine-tuning problem. In the past decade it has been established that spectral lines of atoms and molecules, which can currently be measured at ever-higher accuracies, form an ideal test ground for probing drifting constants. This has brought this subject from the realm of metaphysics to that of experimental science. In particular the spectra of molecules are sensitive for probing a variation of the proton-electron mass ratio μ, either on a cosmological time scale, or on a laboratory time scale. A comparison can be made between spectra of molecular hydrogen observed in the laboratory and at a high redshift (z=2-3), using the Very Large Telescope (Paranal, Chile) and the Keck telescope (Hawaii). This puts a constraint on a varying mass ratio Δμ/μ at the 10^{-5} level. The optical work can also be extended to include CO molecules. Further a novel direction will be discussed: it was discovered that molecules exhibiting hindered internal rotation have spectral lines in the radio-spectrum that are extremely sensitive to a varying proton-electron mass ratio. Such lines in the spectrum of methanol were recently observed with the radio-telescope in Effelsberg (Germany). F. van Weerdenburg, M.T. Murphy, A.L. Malec, L. Kaper, W. Ubachs, Phys. Rev. Lett. 106, 180802 (2011). A. Malec, R. Buning, M.T. Murphy, N. Milutinovic, S.L. Ellison, J.X. Prochaska, L. Kaper, J. Tumlinson, R.F. Carswell, W. Ubachs, Mon. Not. Roy. Astron. Soc. 403, 1541 (2010). E.J. Salumbides, M.L. Niu, J. Bagdonaite, N. de Oliveira, D. Joyeux, L. Nahon, W. Ubachs, Phys. Rev. A 86, 022510
Kriging with Unknown Variance Components for Regional Ionospheric Reconstruction
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Ling Huang
2017-02-01
Full Text Available Ionospheric delay effect is a critical issue that limits the accuracy of precise Global Navigation Satellite System (GNSS positioning and navigation for single-frequency users, especially in mid- and low-latitude regions where variations in the ionosphere are larger. Kriging spatial interpolation techniques have been recently introduced to model the spatial correlation and variability of ionosphere, which intrinsically assume that the ionosphere field is stochastically stationary but does not take the random observational errors into account. In this paper, by treating the spatial statistical information on ionosphere as prior knowledge and based on Total Electron Content (TEC semivariogram analysis, we use Kriging techniques to spatially interpolate TEC values. By assuming that the stochastic models of both the ionospheric signals and measurement errors are only known up to some unknown factors, we propose a new Kriging spatial interpolation method with unknown variance components for both the signals of ionosphere and TEC measurements. Variance component estimation has been integrated with Kriging to reconstruct regional ionospheric delays. The method has been applied to data from the Crustal Movement Observation Network of China (CMONOC and compared with the ordinary Kriging and polynomial interpolations with spherical cap harmonic functions, polynomial functions and low-degree spherical harmonic functions. The statistics of results indicate that the daily ionospheric variations during the experimental period characterized by the proposed approach have good agreement with the other methods, ranging from 10 to 80 TEC Unit (TECU, 1 TECU = 1 × 1016 electrons/m2 with an overall mean of 28.2 TECU. The proposed method can produce more appropriate estimations whose general TEC level is as smooth as the ordinary Kriging but with a smaller standard deviation around 3 TECU than others. The residual results show that the interpolation precision of the
Kriging with Unknown Variance Components for Regional Ionospheric Reconstruction.
Huang, Ling; Zhang, Hongping; Xu, Peiliang; Geng, Jianghui; Wang, Cheng; Liu, Jingnan
2017-02-27
Ionospheric delay effect is a critical issue that limits the accuracy of precise Global Navigation Satellite System (GNSS) positioning and navigation for single-frequency users, especially in mid- and low-latitude regions where variations in the ionosphere are larger. Kriging spatial interpolation techniques have been recently introduced to model the spatial correlation and variability of ionosphere, which intrinsically assume that the ionosphere field is stochastically stationary but does not take the random observational errors into account. In this paper, by treating the spatial statistical information on ionosphere as prior knowledge and based on Total Electron Content (TEC) semivariogram analysis, we use Kriging techniques to spatially interpolate TEC values. By assuming that the stochastic models of both the ionospheric signals and measurement errors are only known up to some unknown factors, we propose a new Kriging spatial interpolation method with unknown variance components for both the signals of ionosphere and TEC measurements. Variance component estimation has been integrated with Kriging to reconstruct regional ionospheric delays. The method has been applied to data from the Crustal Movement Observation Network of China (CMONOC) and compared with the ordinary Kriging and polynomial interpolations with spherical cap harmonic functions, polynomial functions and low-degree spherical harmonic functions. The statistics of results indicate that the daily ionospheric variations during the experimental period characterized by the proposed approach have good agreement with the other methods, ranging from 10 to 80 TEC Unit (TECU, 1 TECU = 1 × 10 16 electrons/m²) with an overall mean of 28.2 TECU. The proposed method can produce more appropriate estimations whose general TEC level is as smooth as the ordinary Kriging but with a smaller standard deviation around 3 TECU than others. The residual results show that the interpolation precision of the new proposed
Kriging with Unknown Variance Components for Regional Ionospheric Reconstruction
Huang, Ling; Zhang, Hongping; Xu, Peiliang; Geng, Jianghui; Wang, Cheng; Liu, Jingnan
2017-01-01
Ionospheric delay effect is a critical issue that limits the accuracy of precise Global Navigation Satellite System (GNSS) positioning and navigation for single-frequency users, especially in mid- and low-latitude regions where variations in the ionosphere are larger. Kriging spatial interpolation techniques have been recently introduced to model the spatial correlation and variability of ionosphere, which intrinsically assume that the ionosphere field is stochastically stationary but does not take the random observational errors into account. In this paper, by treating the spatial statistical information on ionosphere as prior knowledge and based on Total Electron Content (TEC) semivariogram analysis, we use Kriging techniques to spatially interpolate TEC values. By assuming that the stochastic models of both the ionospheric signals and measurement errors are only known up to some unknown factors, we propose a new Kriging spatial interpolation method with unknown variance components for both the signals of ionosphere and TEC measurements. Variance component estimation has been integrated with Kriging to reconstruct regional ionospheric delays. The method has been applied to data from the Crustal Movement Observation Network of China (CMONOC) and compared with the ordinary Kriging and polynomial interpolations with spherical cap harmonic functions, polynomial functions and low-degree spherical harmonic functions. The statistics of results indicate that the daily ionospheric variations during the experimental period characterized by the proposed approach have good agreement with the other methods, ranging from 10 to 80 TEC Unit (TECU, 1 TECU = 1 × 1016 electrons/m2) with an overall mean of 28.2 TECU. The proposed method can produce more appropriate estimations whose general TEC level is as smooth as the ordinary Kriging but with a smaller standard deviation around 3 TECU than others. The residual results show that the interpolation precision of the new proposed
Radiotherapy of metastatic neck nodes from an unknown primary site
International Nuclear Information System (INIS)
Park, I. K.; Yun, S. M.; Kim, J. C.
1997-01-01
This study was to evaluate survival, failure patterns, and prognostic factors of patients with metastatic neck nodes from an unknown primary site. A retrospective analysis was done for 35 patients with metastatic neck nodes from an unknown primary site who were treated with radiation from January 1986 to September 1994. There were 26 male and 9 female patients. Patients' age ranged from 41 to 74 years (median 58 years). Radiation therapy alone was done in 7 patients, induction chemotherapy and radiation therapy in 10, and postoperative radiation therapy in 18. Radiation therapy fields included both neck and pharyngeal axis, and total dose was 40-95.6Gy using 6MV X-ray. Chemotherapy consisted of 2 cycles of 5-fluorouracil and cisplatin. Surgical methods were a radical neck dissection in 17 patients and an excisional biopsy in 1 patient. Follow-up time ranged from 2 to 95 months, median 15 months. Overall and disease-free survival rate at 4 years were 33.4% and 33.9%, respectively. The factors associated with the overall survival rate were histologic type (adenocarcinoma vs. non-adenocarcinoma ), N stage, and the site of involved nodes. According to the treatment modality, 2-year survival rate was 14.3% in radiation therapy alone group, 35.8% in induction chemotherapy and radiation therapy, and 37.5% in postoperative radiation therapy, which might be due to the difference of N stage distribution. Local failure was noted in 7 patients, distant metastases in 6, local failure and distant metastases in 1. Excluding the 7 patients with supraclavicular lymph node metastases alone, 28%(7/25) of the patients had distant metastases. During the follow-up period, 11%(3/35) of the patients showed a delayed primary site, 1 in oral cavity, 1 in nasopharynx and 1 in hypopharynx. N stage, the site of involved node, and histologic type were associated with survival rate. In patients with advanced N stage, curative rather than inductive chemotherapy is needed because combined surgery
Constant-parameter capture-recapture models
Brownie, C.; Hines, J.E.; Nichols, J.D.
1986-01-01
Jolly (1982, Biometrics 38, 301-321) presented modifications of the Jolly-Seber model for capture-recapture data, which assume constant survival and/or capture rates. Where appropriate, because of the reduced number of parameters, these models lead to more efficient estimators than the Jolly-Seber model. The tests to compare models given by Jolly do not make complete use of the data, and we present here the appropriate modifications, and also indicate how to carry out goodness-of-fit tests which utilize individual capture history information. We also describe analogous models for the case where young and adult animals are tagged. The availability of computer programs to perform the analysis is noted, and examples are given using output from these programs.
Gravitational gauge fields and the cosmological constant
International Nuclear Information System (INIS)
Pagels, H.R.
1984-01-01
We describe field theories for which the action is completely independent of the metric and connection of the space-time manifold. The metric in our approach is no more a fundamental field than a hadron field is a fundamental field in QCD. The fundamental fields in the action are O(5) gauge fields and combinations of these fields are interpreted as the metric and connection so that conventional general relativity is obtained. Remarkably, all renormalizable matter actions for scalar, spinor, and Yang-Mills gauge fields can be made metric independent. Significantly, we find a new elementary invariance of the action which implies the cosmological constant must vanish. Finally, we discuss the quantum theory resulting from these ideas
Statistical Modelling of the Soil Dielectric Constant
Usowicz, Boguslaw; Marczewski, Wojciech; Bogdan Usowicz, Jerzy; Lipiec, Jerzy
2010-05-01
The dielectric constant of soil is the physical property being very sensitive on water content. It funds several electrical measurement techniques for determining the water content by means of direct (TDR, FDR, and others related to effects of electrical conductance and/or capacitance) and indirect RS (Remote Sensing) methods. The work is devoted to a particular statistical manner of modelling the dielectric constant as the property accounting a wide range of specific soil composition, porosity, and mass density, within the unsaturated water content. Usually, similar models are determined for few particular soil types, and changing the soil type one needs switching the model on another type or to adjust it by parametrization of soil compounds. Therefore, it is difficult comparing and referring results between models. The presented model was developed for a generic representation of soil being a hypothetical mixture of spheres, each representing a soil fraction, in its proper phase state. The model generates a serial-parallel mesh of conductive and capacitive paths, which is analysed for a total conductive or capacitive property. The model was firstly developed to determine the thermal conductivity property, and now it is extended on the dielectric constant by analysing the capacitive mesh. The analysis is provided by statistical means obeying physical laws related to the serial-parallel branching of the representative electrical mesh. Physical relevance of the analysis is established electrically, but the definition of the electrical mesh is controlled statistically by parametrization of compound fractions, by determining the number of representative spheres per unitary volume per fraction, and by determining the number of fractions. That way the model is capable covering properties of nearly all possible soil types, all phase states within recognition of the Lorenz and Knudsen conditions. In effect the model allows on generating a hypothetical representative of
Hawking temperature of constant curvature black holes
International Nuclear Information System (INIS)
Cai Ronggen; Myung, Yun Soo
2011-01-01
The constant curvature (CC) black holes are higher dimensional generalizations of Banados-Teitelboim-Zanelli black holes. It is known that these black holes have the unusual topology of M D-1 xS 1 , where D is the spacetime dimension and M D-1 stands for a conformal Minkowski spacetime in D-1 dimensions. The unusual topology and time-dependence for the exterior of these black holes cause some difficulties to derive their thermodynamic quantities. In this work, by using a globally embedding approach, we obtain the Hawking temperature of the CC black holes. We find that the Hawking temperature takes the same form when using both the static and global coordinates. Also, it is identical to the Gibbons-Hawking temperature of the boundary de Sitter spaces of these CC black holes.
Dielectric Constant Measurements of Solid 4He
Yin, L.; Xia, J. S.; Huan, C.; Sullivan, N. S.; Chan, M. H. W.
2011-03-01
Careful measurements of the dielectric properties of solid 4He have been carried out down to 35 mK, considerably lower than the temperature range of previous studies. The sample was prepared from high purity gas with 3He concentrations of the order of 200 ppb and were formed by the blocked capillary method. The molar volume of the sample was 20.30 cm3. The dielectric constant of the samples was found to be independent of temperature down to 120 mK before showing a continuous increase with decreasing temperature and saturating below 50 mK. The total increase in ɛ is 2 parts in 10-5. The temperature dependence of ɛ mimics the increase in the resonant frequency found in the torsional oscillator studies and also the increase found in the shear modulus measurements.
On the substructure of the cosmological constant
Dvali, G.; Gomez, C.; Zell, S.
We summarize the findings of our paper arXiv:1701.08776 [hep-th]. We start by defining the quantum break-time. Once one understands a classical solution as expectation value of an underlying quantum state, it emerges as time-scale after which the true quantum evolution departs from the classical mean field evolution. We apply this idea to de Sitter space. Following earlier work, we construct a simple model of a spin-2 field, which for some time reproduces the de Sitter metric and simultaneously allows for its well-defined representation as coherent quantum state of gravitons. The mean occupation number N of background gravitons turns out to be equal to the de Sitter horizon area in Planck units, while their frequency is given by the de Sitter Hubble parameter. In the semi-classical limit, we show that the model reproduces all semi-classical calculations in de Sitter, such as thermal Gibbons-Hawking radiation, all in the language of quantum S-matrix scatterings and decays of coherent state gravitons. Most importantly, this framework allows to capture the (1/N)-effects of back reaction to which the usual semi-classical treatment is blind. They violate the de Sitter symmetry and lead to a finite quantum break-time of the de Sitter state equal to the de Sitter radius times N. We also point out that the quantum-break time is inversely proportional to the number of particle species in the theory. Thus, the quantum break-time imposes the following consistency condition: Older and species-richer universes must have smaller cosmological constants. For the maximal, phenomenologically acceptable number of species, the observed cosmological constant would saturate this bound if our Universe were 10100 years old in its entire classical history.
Higgs inflation and the cosmological constant
Energy Technology Data Exchange (ETDEWEB)
Jegerlehner, Fred [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)
2014-02-15
The Higgs not only induces the masses of all SM particles, the Higgs, given its special mass value, is the natural candidate for the inflaton and in fact is ruling the evolution of the early universe, by providing the necessary dark energy which remains the dominant energy density. SM running couplings not only allow us to extrapolate SM physics up to the Planck scale, but equally important they are triggering the Higgs mechanism. This is possible by the fact that the bare mass term in the Higgs potential changes sign at about μ{sub 0}≅1.40 x 10{sup 16} GeV and in the symmetric phase is enhanced by quadratic terms in the Planck mass. Such a huge Higgs mass term is able to play a key role in triggering inflation in the early universe. In this article we extend our previous investigation by working out the details of a Higgs inflation scenario. We show how different terms contributing to the Higgs Lagrangian are affecting inflation. Given the SM and its extrapolation to scales μ>μ{sub 0} we find a calculable cosmological constant V(0) which is weakly scale dependent and actually remains large during inflation. This is different to the Higgs fluctuation field dependent ΔV(φ), which decays exponentially during inflation, and actually would not provide a sufficient amount of inflation. The fluctuation field has a different effective mass which shifts the bare Higgs transition point to a lower value μ'{sub 0} ≅7.7 x 10{sup 14} GeV. The vacuum energy V(0) being proportional to M{sub Pl}{sup 4} has a coefficient which vanishes near the Higgs transition point, such that the bare and the renormalized cosmological constant match at this point. The role of the Higgs in reheating and baryogenesis is emphasized.
Universal equations and constants of turbulent motion
Baumert, H. Z.
2013-07-01
This paper presents a parameter-free theory of shear-generated turbulence at asymptotically high Reynolds numbers in incompressible fluids. It is based on a two-fluids concept. Both components are materially identical and inviscid. The first component is an ensemble of quasi-rigid dipole-vortex tubes (vortex filaments, excitations) as quasi-particles in chaotic motion. The second is a superfluid performing evasive motions between the tubes. The local dipole motions follow Helmholtz' law. The vortex radii scale with the energy-containing length scale. Collisions between quasi-particles lead either to annihilation (likewise rotation, turbulent dissipation) or to scattering (counterrotation, turbulent diffusion). There are analogies with birth and death processes of population dynamics and their master equations and with Landau's two-fluid theory of liquid helium. For free homogeneous decay the theory predicts the turbulent kinetic energy to follow t-1. With an adiabatic wall condition it predicts the logarithmic law with von Kármán's constant as 1/\\sqrt {2\\,\\pi }= 0.399 . Likewise rotating couples form localized dissipative patches almost at rest (→ intermittency) wherein under local quasi-steady conditions the spectrum evolves into an ‘Apollonian gear’ as discussed first by Herrmann (1990 Correlation and Connectivity (Dordrecht: Kluwer) pp 108-20). Dissipation happens exclusively at scale zero and at finite scales this system is frictionless and reminds of Prigogine's (1947 Etude Thermodynamique des Phenomenes Irreversibles (Liege: Desoer) p 143) law of minimum (here: zero) entropy production. The theory predicts further the prefactor of the 3D-wavenumber spectrum (a Kolmogorov constant) as \\frac {1}{3}(4\\,\\pi )^{2/3}=1.802 , well within the scatter range of observational, experimental and direct numerical simulation results.
In search of lost time constants and of non-Michaelis–Menten parameters
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Maria F. Pinto
2016-12-01
Full Text Available Upon completing 100 years since it was published, the work Die Kinetik der Invertinwirkung by Michaelis and Menten (MM was celebrated during the 6th Beilstein ESCEC Symposium 2013. As the 7th Beilstein ESCEC Symposium 2015 debates enzymology in the context of complex biological systems, a post-MM approach is required to address cell-like conditions that are well beyond the steady-state limitations. The present contribution specifically addresses two hitherto ambiguous constants whose interest was, however, intuited in the original MM paper: (i the characteristic time constant τ∞, which can be determined using the late stages of any progress curve independently of the substrate concentration adopted; and (ii the dissociation constant KS, which is indicative of the enzyme–substrate affinity and completes the kinetic portrayal of the Briggs–Haldane reaction scheme. The rationale behind τ∞ and KS prompted us to revise widespread concepts of enzyme's efficiency, defined by the specificity constant kcat/KM, and of the Michaelis constant KM seen as the substrate concentration yielding half-maximal rates. The alternative definitions here presented should help recovering the wealth of published kcat/KM and KM data from the criticism that they are subjected. Finally, a practical method is envisaged for objectively determining enzyme's activity, efficiency and affinity – (EA2 – from single progress curves. The (EA2 assay can be conveniently applied even when the concentrations of substrate and enzyme are not accurately known.
Fluorodeoxyglucose rate constants, lumped constant, and glucose metabolic rate in rabbit heart
International Nuclear Information System (INIS)
Krivokapich, J.; Huang, S.C.; Selin, C.E.; Phelps, M.E.
1987-01-01
The isolated arterial perfused rabbit interventricular septum was used to measure myocardial metabolic rate for glucose (MMRGlc) and rate constants and lumped constant (LC) for the glucose analogue [ 18 F]fluorodeoxyglucose (FDG) using a tracer kinetic model. FDG was delivered by constant infusion during coincidence counting of tissue 18 F radioactivity. The MMRGlc was measured by the Fick method. Control septa were paced at 72 beats/min and perfused at 1.5 ml/min with oxygenated perfusate containing 5.6 mM glucose and 5 mU/ml insulin. The following conditions were tested: 3.0 and 4.5 ml/min; insulin increased to 25 mU/ml; insulin omitted; 2.8 mM and 11.2 mM glucose; 144 beats/min and 96 paired stimuli/min; and anoxia. Under all conditions studied the phosphorylation (hexokinase) reaction was rate limiting relative to transport. Compared with control conditions, the phosphorylation rate constant was significantly increased with 2.8 mM glucose as well as in anoxia. With 4.5 ml/min and 11.2 mM glucose, conditions that should increase glucose flux into tissue without increasing demand, the phosphorylation rate constant decreased significantly. With 11.2 mM glucose, 96 paired stimuli/min, and anoxia without insulin, a significant increase in the hydrolysis rate of FDG 6-phosphate was observed and suggests that hydrolysis is also an important mechanism for regulating the MMRGlc. Increased transport rate constants were observed with increased flow rates, 96 paired stimuli/min, and anoxia at 96 beats/min. The LC was not significantly different from control in 11 of 14 conditions studied. Therefore, under most conditions in average LC can be used to calculate MMRGlc estimates
Chronic kidney disease of unknown etiology in Sri Lanka.
Rajapakse, Senaka; Shivanthan, Mitrakrishnan Chrishan; Selvarajah, Mathu
2016-07-01
In the last two decades, chronic kidney disease of unknown etiology (CKDu) has emerged as a significant contributor to the burden of chronic kidney disease (CKD) in rural Sri Lanka. It is characterized by the absence of identified causes for CKD. The prevalence of CKDu is 15.1-22.9% in some Sri Lankan districts, and previous research has found an association with farming occupations. A systematic literature review in Pubmed, Embase, Scopus, and Lilacs databases identified 46 eligible peer-reviewed articles and one conference abstract. Geographical mapping indicates a relationship between CKDu and agricultural irrigation water sources. Health mapping studies, human biological studies, and environment-based studies have explored possible causative agents. Most studies focused on likely causative agents related to agricultural practices, geographical distribution based on the prevalence and incidence of CKDu, and contaminants identified in drinking water. Nonetheless, the link between agrochemicals or heavy metals and CKDu remains to be established. No definitive cause for CKDu has been identified. Evidence to date suggests that the disease is related to one or more environmental agents, however pinpointing a definite cause for CKDu is challenging. It is plausible that CKDu is multifactorial. No specific guidelines or recommendations exist for treatment of CKDu, and standard management protocols for CKD apply. Changes in agricultural practices, provision of safe drinking water, and occupational safety precautions are recommended by the World Health Organization.
Familial clustering of Leiomyomatosis peritonealis disseminata: an unknown genetic syndrome?
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Daboul Isam
2005-10-01
Full Text Available Abstract Background Leiomyomatosis peritonealis disseminata (LPD is defined as the occurrence of multiple tumorous intraabdominal lesions, which are myomatous nodules. LPD is a rare disease with only about 100 cases reported. The usual course of LPD is benign with the majority of the patients being premenopausal females. Only two cases involving men have been reported, no syndrome or familial occurrence of LPD has been described. Case presentation We describe a Caucasian-American family in which six members (three men are diagnosed with Leiomyomatosis peritonealis disseminata (LPD and three deceased family members most likely had LPD (based on the autopsy reports. Furthermore we describe the association of LPD with Raynaud's syndrome and Prurigo nodularis. Conclusion Familial clustering of Leiomyomatosis peritonealis disseminata (LPD has not been reported so far. The etiology of LPD is unknown and no mode of inheritance is known. We discuss possible modes of inheritance in the presented case, taking into account the possibility of a genetic syndrome. Given the similarity to other genetic syndromes with leiomyomatosis and skin alterations, we describe possible similar genetic pathomechanisms.
Systemic treatment of cancer of unknown primary origin
International Nuclear Information System (INIS)
Reckova, M.
2013-01-01
Cancer of unknown primary origin (CUP) comprises a heterogenous group of cancers with distinct biology and prognosis. There is, however, a specific group of patients with curable diseases, or incurable diseases with good prognosis. The main aim of treatment in the group of patients with CUP is timely initiation of therapy in the cases of curable disease. There is no known standard of care in the cases of CUP with poor prognosis, but most frequently, platinum-based regimens are used. In the cases of specific immunohistochemistry (IHC) or molecular gene expression profile, there are used the treatment regimens similar to those used in the patients with known primary tumor and similar IHC or molecular profile. Currently, most of data in patients with CUP are from phase II clinical trials. Thus proficiently designed phase III randomized clinical trials with translation research is priority, with aim to improve our knowledge and personalize treatment of such heterogenous group of patients as is a group of patients with CUP. (author)
Radiotherapeutic concepts in cancer of unknown primary site
International Nuclear Information System (INIS)
Krug, D.; Debus, J.; Sterzing, F.
2014-01-01
The term cancer of unknown primary (CUP) encompasses a group of entities which differ to a great extent regarding etiology, prognosis and therapeutic management. The aim of the study was an elaboration of the role of radiotherapy in CUP syndrome. Systematic literature search and specification of the available treatment options. Radiotherapy is an integral part of interdisciplinary management approaches for patients with CUP in both curative and palliative situations. Radio-oncological techniques, such as intensity-modulated radiotherapy and stereotactic body radiotherapy increase the therapeutic window. Modern diagnostic modalities from radiology and nuclear medicine are the cornerstone of radiotherapeutic interventions, especially in terms of target volume definition and pretherapeutic staging. In the interdisciplinary setting radiation oncology offers the possibility of curative and often organ preserving approaches in patients with axillary and cervical CUP. In addition, improvement and preservation of quality of life can be achieved in patients with metastatic disease. Radiation oncology is a crucial component of the interdisciplinary management of patients with CUP. Therapeutic decisions in patients with CUP should be made in an interdisciplinary setting. (orig.) [de
Exploration for Agents with Different Personalities in Unknown Environments
Doumit, Sarjoun; Minai, Ali
We present in this paper a personality-based architecture (PA) that combines elements from the subsumption architecture and reinforcement learning to find alternate solutions for problems facing artificial agents exploring unknown environments. The underlying PA algorithm is decomposed into layers according to the different (non-contiguous) stages that our agent passes in, which in turn are influenced by the sources of rewards present in the environment. The cumulative rewards collected by an agent, in addition to its internal composition serve as factors in shaping its personality. In missions where multiple agents are deployed, our solution-goal is to allow each of the agents develop its own distinct personality in order for the collective to reach a balanced society, which then can accumulate the largest possible amount of rewards for the agent and society as well. The architecture is tested in a simulated matrix world which embodies different types of positive rewards and negative rewards. Varying experiments are performed to compare the performance of our algorithm with other algorithms under the same environment conditions. The use of our architecture accelerates the overall adaptation of the agents to their environment and goals by allowing the emergence of an optimal society of agents with different personalities. We believe that our approach achieves much efficient results when compared to other more restrictive policy designs.
Physics at 13 TeV: CMS - scanning the unknown
Antonella Del Rosso
2014-01-01
CMS is getting ready to use its accurate detector to scan the many ripples of the unknown physics that may lie beyond the Standard Model. Foremost in everyone’s mind is the search for signs of the production of dark matter at a man-made machine. Interestingly, the observation of dark matter or new weakly interacting particles implies detecting that some energy has escaped, i.e. it’s missing from the upcoming proton collisions at the LHC. This is why measuring and understanding “missing energy” will be a very important step in that direction. “A large amount of missing energy is the signature for many processes of physics beyond the Standard Model. However, it’s not the only interesting signature that we will be able to exploit when the new collision energy is available,” explains Luca Malgeri, CMS Physics Coordinator. Among the interesting things not associated with missing energy are high-mass resonanc...
Developing Probabilistic Safety Performance Margins for Unknown and Underappreciated Risks
Benjamin, Allan; Dezfuli, Homayoon; Everett, Chris
2015-01-01
Probabilistic safety requirements currently formulated or proposed for space systems, nuclear reactor systems, nuclear weapon systems, and other types of systems that have a low-probability potential for high-consequence accidents depend on showing that the probability of such accidents is below a specified safety threshold or goal. Verification of compliance depends heavily upon synthetic modeling techniques such as PRA. To determine whether or not a system meets its probabilistic requirements, it is necessary to consider whether there are significant risks that are not fully considered in the PRA either because they are not known at the time or because their importance is not fully understood. The ultimate objective is to establish a reasonable margin to account for the difference between known risks and actual risks in attempting to validate compliance with a probabilistic safety threshold or goal. In this paper, we examine data accumulated over the past 60 years from the space program, from nuclear reactor experience, from aircraft systems, and from human reliability experience to formulate guidelines for estimating probabilistic margins to account for risks that are initially unknown or underappreciated. The formulation includes a review of the safety literature to identify the principal causes of such risks.
Fever in Children and Fever of Unknown Origin.
Dayal, Rajeshwar; Agarwal, Dipti
2016-01-01
Fever is the most common symptom in children and can be classified as fever with or without focus. Fever without focus can be less than 7 d and is subclassified as fever without localizing signs and fever of unknown origin (FUO). FUO is defined as a temperature greater than 38.3 °C, for more than 3 wk or failure to reach a diagnosis after 1 wk of inpatient investigations. The most common causes of FUO in children are infections, connective tissue disorders and neoplasms. Infectious diseases most commonly implicated in children with FUO are salmonellosis, tuberculosis, malaria and rickettsial diseases. Juvenile rheumatic arthritis is the connective tissue disease frequently associated with FUO. Malignancy is the third largest group responsible for FUO in children. Diagnostic approach of FUO includes detailed history and examination supported with investigations. Age, history of contact, exposure to wild animals and medications should be noted. Examination should include, apart from general appearance, presence of sweating, rashes, tonsillitis, sinusitis and lymph node enlargement. Other signs such as abdominal tenderness and hepatosplenomegly should be looked for. The muscles and bones should be carefully examined for connective tissue disorders. Complete blood count, blood smear examination and level of acute phase reactants should be part of initial investigations. Radiological imaging is useful aid in diagnosing FUO. Trials of antimicrobial agents should not be given as they can obscure the diagnosis of the disease in FUO.
Fever of unknown origin: Most frequent causes in adults patients.
Popovska-Jovicić, Biljana; Canović, Predrag; Gajović, Olgica; Raković, Ivana; Mijailović, Zeljko
2016-01-01
The differential diagnosis of fever of unknown origin (FUO) includes more than 200 different diseases and conditions. The aim of this study was to identify the most frequent causes of FUO among adult patients according to gender and age. The study included 74 patients examined from June 2010 to June 2013 at the Infectious Disease Clinic, Clinical Center Kragujevac in Serbia, according to the defined criteria for FUO. The patients were divided according to the diagnosis into four groups: infectious, malignant, rheumatic and "other diseases". A cause of febricity could not be estabilshed in a portion of subjects, and they comprised the group of undiagnosed cases. Infectious diseases were dominant in the study, followed by rheumatic diseases, which were most frequently found in women and the elderly. The diseases recognised as the most common causes of febricity were subacute thyroiditis, subacute endocarditis, Still's disease, rheumatic polymyalgia with or without temporal arteritis, and cytomegalovirus infection. In 44% of the patients, the final diagnosis was composed of only six clinical entities. The importance of establishing the diagnosis of rheumatic disease is especially emphasised, in line with other authors' research indicating the number of these diseases is on the rise. The diagnostic approach to FUO should always be directed to the known frequency of diseases.
Investigation of cervical lymph node metastasis from primary unknown carcinoma
International Nuclear Information System (INIS)
Sagawa, Kosuke; Terada, Tomonori; Saeki, Nobuo; Uwa, Nobuhiro; Mohri, Takeshi; Sakagami, Masafumi
2012-01-01
We retrospectively evaluated 41 patients with metastatic cervical tumors from unknown primary sites at the Hyogo College of Medicine between 1997 and 2007. The N stage classification of cervical lymph nodes was: N1 in 3 cases, N2a in 10 cases, N2b in 10 cases, N2c in 4 cases, and N3 in 14 cases. The histopathological diagnoses of cervical lymph node were: squamous cell carcinoma in 33 cases, adenocarcinoma in 5 cases, undifferentiated carcinoma in 2 cases, and papillary carcinoma in 1 cases. Primary tumor sites were: tonsil in 5 cases, esophaguses in 2 cases, hypopharynxies in 2 cases, and thyroid, oral floor, submandibular gland, lung, gastric and colon in 1 case each. The useful tests were gastric endoscope, positron emission tomography-computed tomography (PET-CT), and blind biopsy of tonsil. We treated 24 of the 41 patients. Therapies were: neck dissection with postoperative radiation therapy in 11 cases, neck dissection alone in 1 case, only radiation or chemoradiation therapy alone in 8 cases, and chemotherapy alone in 4 cases. The 5-year survival rate was 40.1% in all cases and 81.5% in cases who underwent neck dissection. (author)
Kidnapping Detection and Recognition in Previous Unknown Environment
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Yang Tian
2017-01-01
Full Text Available An unaware event referred to as kidnapping makes the estimation result of localization incorrect. In a previous unknown environment, incorrect localization result causes incorrect mapping result in Simultaneous Localization and Mapping (SLAM by kidnapping. In this situation, the explored area and unexplored area are divided to make the kidnapping recovery difficult. To provide sufficient information on kidnapping, a framework to judge whether kidnapping has occurred and to identify the type of kidnapping with filter-based SLAM is proposed. The framework is called double kidnapping detection and recognition (DKDR by performing two checks before and after the “update” process with different metrics in real time. To explain one of the principles of DKDR, we describe a property of filter-based SLAM that corrects the mapping result of the environment using the current observations after the “update” process. Two classical filter-based SLAM algorithms, Extend Kalman Filter (EKF SLAM and Particle Filter (PF SLAM, are modified to show that DKDR can be simply and widely applied in existing filter-based SLAM algorithms. Furthermore, a technique to determine the adapted thresholds of metrics in real time without previous data is presented. Both simulated and experimental results demonstrate the validity and accuracy of the proposed method.
Crowdsourcing the unknown: the satellite search for Genghis Khan.
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A Y M Lin
Full Text Available Massively parallel collaboration and emergent knowledge generation is described through a large scale survey for archaeological anomalies within ultra-high resolution earth-sensing satellite imagery. Over 10K online volunteers contributed 30K hours (3.4 years, examined 6,000 km², and generated 2.3 million feature categorizations. Motivated by the search for Genghis Khan's tomb, participants were tasked with finding an archaeological enigma that lacks any historical description of its potential visual appearance. Without a pre-existing reference for validation we turn towards consensus, defined by kernel density estimation, to pool human perception for "out of the ordinary" features across a vast landscape. This consensus served as the training mechanism within a self-evolving feedback loop between a participant and the crowd, essential driving a collective reasoning engine for anomaly detection. The resulting map led a National Geographic expedition to confirm 55 archaeological sites across a vast landscape. A increased ground-truthed accuracy was observed in those participants exposed to the peer feedback loop over those whom worked in isolation, suggesting collective reasoning can emerge within networked groups to outperform the aggregate independent ability of individuals to define the unknown.
How to know unknown fungi: the role of a herbarium.
Brock, Patrick M; Döring, Heidi; Bidartondo, Martin I
2009-01-01
The development of a universal approach to the identification of fungi from the environment is impeded by the limited number and narrow phylogenetic range of the named internal transcribed spacer DNA sequences available on GenBank. The goal here was to assess the potential impact of systematic DNA sequencing from a fungal herbarium collection. DNA sequences were generated from a diverse set of 279 specimens deposited at the fungal herbarium of the Royal Botanic Gardens at Kew (UK) and bioinformatic analyses were used to study their overlap with the public database. It is estimated that c. 70% of the herbarium taxonomic diversity is not yet represented in GenBank and that a further c. 10% of our sequences match solely to 'environmental samples' or fungi otherwise unidentified. Here it is shown that the unsampled diversity residing in fungal herbaria can substantially enlarge the coverage of GenBank's fully identified sequence pool to ameliorate the problem of environmental unknowns and to aid in the detection of truly novel fungi by molecular data.
Ultrastructural mitochondrial alterations in equine myopathies of unknown origin.
Van Driessche, K; Ducatelle, R; Chiers, K; Van Coster, R; van der Kolk, J H; van der Kolk, H
2015-03-01
Very few mitochondrial myopathies have been described in horses. To examine the ultrastructure of muscle mitochondria in equine cases of myopathy of unknown origin. Biopsies of vastus lateralis of the Musculus quadriceps femoris were taken predominantly immediately post mortem and processed for transmission electron microscopy. As a result, electron micrographs of 90 horses in total were available for analysis comprising 4 control horses, 16 horses suffering from myopathy and 70 otherwise diseased horses. Following a thorough clinical and laboratory work-up, four out of five patients that did not fit into the usual algorithm to detect known causes of myopathy showed ultrastructural mitochondrial alterations. Small mitochondria with zones with complete disruption of cristae associated with lactic acidemia were detected in a 17-year-old pony mare, extremely long and slender mitochondria with longitudinal cristae in a 5-year-old Quarter horse stallion, a mixture of irregular extremely large mitochondria (measuring 2500 by 800 nm) next to smaller ones in an 8-year-old Hanoverian mare and round mitochondria with only few cristae in a 11-year-old pony gelding. It remains uncertain whether the subsarcolemmal mitochondrial accumulations observed in the fifth patient have any pathological significance. Ultrastructural alterations in mitochondria were detected in at least four horses. To conclude that these are due to mitochondrial dysfuntions, biochemical tests should be performed. The possibility of a mitochondrial myopathy should be included in the differential diagnosis of muscle weakness.
Challenges of the Unknown: Clinical Application of Microbial Metagenomics
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Graham Rose
2015-01-01
Full Text Available Availability of fast, high throughput and low cost whole genome sequencing holds great promise within public health microbiology, with applications ranging from outbreak detection and tracking transmission events to understanding the role played by microbial communities in health and disease. Within clinical metagenomics, identifying microorganisms from a complex and host enriched background remains a central computational challenge. As proof of principle, we sequenced two metagenomic samples, a known viral mixture of 25 human pathogens and an unknown complex biological model using benchtop technology. The datasets were then analysed using a bioinformatic pipeline developed around recent fast classification methods. A targeted approach was able to detect 20 of the viruses against a background of host contamination from multiple sources and bacterial contamination. An alternative untargeted identification method was highly correlated with these classifications, and over 1,600 species were identified when applied to the complex biological model, including several species captured at over 50% genome coverage. In summary, this study demonstrates the great potential of applying metagenomics within the clinical laboratory setting and that this can be achieved using infrastructure available to nondedicated sequencing centres.
Overfitting Bayesian Mixture Models with an Unknown Number of Components.
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Zoé van Havre
Full Text Available This paper proposes solutions to three issues pertaining to the estimation of finite mixture models with an unknown number of components: the non-identifiability induced by overfitting the number of components, the mixing limitations of standard Markov Chain Monte Carlo (MCMC sampling techniques, and the related label switching problem. An overfitting approach is used to estimate the number of components in a finite mixture model via a Zmix algorithm. Zmix provides a bridge between multidimensional samplers and test based estimation methods, whereby priors are chosen to encourage extra groups to have weights approaching zero. MCMC sampling is made possible by the implementation of prior parallel tempering, an extension of parallel tempering. Zmix can accurately estimate the number of components, posterior parameter estimates and allocation probabilities given a sufficiently large sample size. The results will reflect uncertainty in the final model and will report the range of possible candidate models and their respective estimated probabilities from a single run. Label switching is resolved with a computationally light-weight method, Zswitch, developed for overfitted mixtures by exploiting the intuitiveness of allocation-based relabelling algorithms and the precision of label-invariant loss functions. Four simulation studies are included to illustrate Zmix and Zswitch, as well as three case studies from the literature. All methods are available as part of the R package Zmix, which can currently be applied to univariate Gaussian mixture models.
Overfitting Bayesian Mixture Models with an Unknown Number of Components.
van Havre, Zoé; White, Nicole; Rousseau, Judith; Mengersen, Kerrie
2015-01-01
This paper proposes solutions to three issues pertaining to the estimation of finite mixture models with an unknown number of components: the non-identifiability induced by overfitting the number of components, the mixing limitations of standard Markov Chain Monte Carlo (MCMC) sampling techniques, and the related label switching problem. An overfitting approach is used to estimate the number of components in a finite mixture model via a Zmix algorithm. Zmix provides a bridge between multidimensional samplers and test based estimation methods, whereby priors are chosen to encourage extra groups to have weights approaching zero. MCMC sampling is made possible by the implementation of prior parallel tempering, an extension of parallel tempering. Zmix can accurately estimate the number of components, posterior parameter estimates and allocation probabilities given a sufficiently large sample size. The results will reflect uncertainty in the final model and will report the range of possible candidate models and their respective estimated probabilities from a single run. Label switching is resolved with a computationally light-weight method, Zswitch, developed for overfitted mixtures by exploiting the intuitiveness of allocation-based relabelling algorithms and the precision of label-invariant loss functions. Four simulation studies are included to illustrate Zmix and Zswitch, as well as three case studies from the literature. All methods are available as part of the R package Zmix, which can currently be applied to univariate Gaussian mixture models.
[On true and apparent Michaelis constants in enzymology. I. Differences].
Karakhim, S A
2011-01-01
Differences between both true and apparent rate constants and Michaelis constants have been examined. Rate constants of elementary stages of real mechanisms are true ones. True Michaelis constant Km is expressed by equation Km = (k(-1) + k2)/k. True constants may be determined for reliable mechanism only for which the equation of initial rate was obtained which displays physical sense of these constants and permits to find the method of their calculation. The true constant values are independent of concentration of reactants, activators, inhibitors, extraneous agents and pH. The apparent rate constants are such constants of the composite reaction which are observed when this reaction is described by the equation of simple reaction. Michaelis constant calculated by a half of the ultimate constant is an apparent constant. The apparent constants may be functions of several true rate constants and/or concentrations of reacting substances. The evident physical sense of apparent constants being absent, only formal relation between the reaction rate and reactant concentration independent of the investigated mechanism is provided.
Constant Leverage And Constant Cost Of Capital: A Common Knowledge Half-Truth
Directory of Open Access Journals (Sweden)
Ignacio Vélez–Pareja
2008-04-01
In this document we show that for finite cash flows, Ke and hence WACC depend on the discount rate that is used to value the tax shield, TS and as expected, Ke and WACC are not constant with Kd as the discount rate for the tax shield, even if the leverage is constant. We illustrate this situation with a simple example. We analyze five methods: DCF using APV, FCF and traditional and general formulation for WACC, present value of CFE plus debt and Capital Cash Flow, CCF.
Analytical estimation of the gravitational constant with atomic and nuclear physical constants
International Nuclear Information System (INIS)
Seshavatharam, U.V.S.; Lakshminarayana, S.
2015-01-01
If N A represents the Avogadro's number, gravitational constant associated with atomic electromagnetic interaction can be expressed as G E ≅ N 2 A G. With G E and with the assumed two new pseudo numbers x ≈ 38.725 and y ≈ 47.415, value of G can be fixed for 10 digits in a verifiable approach. (x, y) can be called as the back ground analytical numbers using by which micro-macro physical constants can be interlinked qualitatively and quantitatively
Schiebl, M.; Zelenka, Z.; Buchner, C.; Pohl, R.; Steindl, D.
2018-02-01
In this study, the influence of the unknown sinker temperature on the measured density of liquids is evaluated. Generally, due to the intrinsic temperature instability of the heat bath temperature controller, the system will never reach thermal equilibrium but instead will oscillate around a mean temperature. The sinker temperature follows this temperature oscillation with a certain time lag. Since the sinker temperature is not measured directly in a hydrostatic weighing apparatus, the temperature of the sinker, and thus in turn the volume of the sinker, is not known exactly. As a consequence, this leads to uncertainty in the value of the density of the liquid. From an analysis of the volume relaxation of the sinker immersed into a heat bath with time-dependent temperature characteristics, the heat transfer coefficient can be estimated, and thus a characteristic time constant for achieving quasi thermal equilibrium for a hydrostatic weighing apparatus is proposed. Additionally, from a theoretical analysis of the transient behavior of the sinker volume, the systematic deviation of the theoretical to the actual measured liquid density is calculated.
77 FR 48429 - Commission Address Change
2012-08-14
... Commission Address Change AGENCY: Federal Mine Safety and Health Review Commission (FMSHRC). ACTION: Final... office and is amending its regulations to inform the public of the address change. DATES: This final rule... dealing with only a change in address. The Commission is an independent regulatory agency and, as such, is...
2010-07-01
... FINANCIAL RESPONSIBILITY AND COMPENSATION OFFSHORE OIL POLLUTION COMPENSATION FUND General § 135.9 Fund address. The address to which correspondence relating to the Coast Guard's administration of the Fund... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Fund address. 135.9 Section 135.9...
Effects of constant voltage and constant current stress in PCBM:P3HT solar cells
DEFF Research Database (Denmark)
Cester, Andrea; Rizzo, Aldo; Bazzega, A.
2015-01-01
The aimof this work is the investigation of forward and reverse bias stress effects, cell self-heating and annealing in roll coated organic solar cells with PCBM:P3HT active layer. In reverse bias stress cells show a constant degradation over time. In forward current stress cells alternate...
Some aspects of preparation and testing of group constants group constant system ABBN-90
International Nuclear Information System (INIS)
Nikolaev, M.N.; Tsiboulia, A.M.; Manturov, G.N.
1996-01-01
This paper presents an overview of activities performed to prepare and test the group constants ABBN-90. The ABBN-90 set is designed for application calculations of fast, intermediate and thermal nuclear reactors. The calculations of subgroup parameters are discussed. The processing code system GRUCON is mentioned in comparison to the NJOY code system. Proposals are made for future activities. (author). Figs, tabs
Riddle, Bob
Researchers have found that gay and lesbian adolescents are at greater risk of isolation, rejection, harassment, violence, and suicide. In a similar way, lesbian and gay teachers face challenges unknown to their heterosexual colleagues. This resource guide is an attempt to outline some of the areas in which independent schools can address issues…
Popular Music in Jia Zhangke’s Unknown Pleasures
Directory of Open Access Journals (Sweden)
Jie Zhang
2011-04-01
Full Text Available With his documentary-style films reflecting upon China’s unprecedented transformation from a state-controlled to a market-driven economy, Jia Zhangke has risen from within the movement of independent Chinese cinema that began to flourish in the late 1990s to become one of the most recognized filmmakers of contemporary China. Born in 1970 and raised in the underdeveloped Shanxi Province, Jia studied film theory at Beijing Film Academy and was first noticed for his controversial “Hometown Trilogy”—'Pickpocket '('Xiao Wu', 1997, 'Platform '('Zhantai', 1999, and 'Unknown Pleasures '('Ren xiao yao', 2002. These three films, shot with handheld video camera on the streets of his hometown province, focus on the reckless changes that China’s aggressive economic growth and globalization have brought to socially marginalized groups. Like other independently made films—films that are produced with capital from outside the state-sponsored avenues and without the approval of film censorship, and that are not allowed to be shown in China’s public theaters—Jia’s first three films reach domestic audiences only through unofficial DVD copies and small-scaled screenings at universities, film bars, and art salons. His limited domestic influence sharply contrasts with the critical acclaim that he receives from international film festival audiences, who are searching for alternative film culture from China after the Fifth Generation directors. By the late 1990s, Jia had become a spokesperson for an ever-increasing group of aspiring Chinese independent filmmakers, particularly through writings and interviews that theorize independent Chinese cinema’s practice.
Vestibular Function in Adults With Epilepsy of Unknown Etiology.
Hamed, Sherifa A; Tohamy, Amal M; Oseilly, Amira M
2017-09-01
This study aimed to evaluate vestibular function in adults with chronic epilepsy of unknown etiology in the inter-ictal period. Epilepsy is a chronic medical disorder. Life-long therapy may be required in one-third of patients. Epilepsy is associated with comorbid somatic conditions which impairs patients' quality of life. This cross-sectional study included 28 with generalized tonic clonic (GTC) convulsions and 14 and 3 with temporal (TLE) and frontal lobe (FLE) epilepsies with secondary generalization (all were on regular carbamazepine therapy) and 40 healthy control subjects. The patients' mean age was 34.97 ± 7.35 years and the duration of illness was 18.75 ± 7.99 years. All underwent videonystagmography (VNG). Compared with controls, patients had frequent vestibular symptoms including dizziness (62.22%) (p = 0.0001) and sense of imbalance (44.44%) (p = 0.0001). Eleven patients (24.44%) had central vestibular dysfunction (p = 0.0001); 9 (20%) had mixed vestibular dysfunction and one (2.22%) had peripheral vestibular dysfunction (p = 0.0001). Abnormalities were observed in saccadic (44.4%) and pursuit (42.2%) eye movements, optokinetic nystagmus (42.2%) and positioning/positional (11.11%) and caloric (13.33%) testing. TLE and FLE were associated with more VNG abnormalities than GTC. No significant differences were observed in the demographic and clinical characteristics between patients with and without VNG abnormalities. Vestibular manifestations are frequent in patients with epilepsy. This may be a result of the permanent damaging effect of chronic epilepsy on the vestibular cortical areas and/or a toxic effect from prolonged carbamazepine therapy on the peripheral and central vestibular systems.
Known unknowns: indirect energy effects of information and communication technology
Horner, Nathaniel C.; Shehabi, Arman; Azevedo, Inês L.
2016-10-01
Background. There has been sustained and growing interest in characterizing the net energy impact of information and communication technology (ICT), which results from indirect effects offsetting (or amplifying) the energy directly consumed by ICT equipment. These indirect effects may be either positive or negative, and there is considerable disagreement as to the direction of this sign as well as the effect magnitude. Literature in this area ranges from studies focused on a single service (such as e-commerce versus traditional retail) to macroeconomic studies attempting to characterize the overall impact of ICT. Methods. We review the literature on the indirect energy effect of ICT found via Google Scholar, our own research, and input from other researchers in the field. The various studies are linked to an effect taxonomy, which is synthesized from several different hierarchies present in the literature. References are further grouped according to ICT service (e.g., e-commerce, telework) and summarized by scope, method, and quantitative and qualitative findings. Review results. Uncertainty persists in understanding the net energy effects of ICT. Results of indirect energy effect studies are highly sensitive to scoping decisions and assumptions made by the analyst. Uncertainty increases as the impact scope broadens, due to complex and interconnected effects. However, there is general agreement that ICT has large energy savings potential, but that the realization of this potential is highly dependent on deployment details and user behavior. Discussion. While the overall net effect of ICT is likely to remain unknown, this review suggests several guidelines for improving research quality in this area, including increased data collection, enhancing traditional modeling studies with sensitivity analysis, greater care in scoping, less confidence in characterizing aggregate impacts, more effort on understanding user behavior, and more contextual integration across the
Zhang, Ruikun; Hou, Zhongsheng; Chi, Ronghu; Ji, Honghai
2015-06-01
In this work, an adaptive iterative learning control (AILC) scheme is proposed to address a class of nonlinearly parameterised systems with both unknown time-varying delays and input saturations. By incorporating a saturation function, a novel iterative learning control mechanism is constructed with a feedback term in the time domain and a fully saturated adaptive learning term in the iteration domain, which is used to estimate the unknown time-varying system uncertainty. A new time-weighted Lyapunov-Krasovskii-like composite energy function (LKL-CEF) is designed for the convergence analysis where time-weighted inputs, states and estimates of system uncertainty are all considered. Despite the existence of time-varying parametric uncertainties, time-varying delays, input saturations and local Lipschitz nonlinearities, the learning convergence is guaranteed with rigorous mathematical analysis. Simulation results verify the correctness and effectiveness of the proposed method further.
Analysis of the chemical equilibrium of combustion at constant volume
Directory of Open Access Journals (Sweden)
Marius BREBENEL
2014-04-01
Full Text Available Determining the composition of a mixture of combustion gases at a given temperature is based on chemical equilibrium, when the equilibrium constants are calculated on the assumption of constant pressure and temperature. In this paper, an analysis of changes occurring when combustion takes place at constant volume is presented, deriving a specific formula of the equilibrium constant. The simple reaction of carbon combustion in pure oxygen in both cases (constant pressure and constant volume is next considered as example of application, observing the changes occurring in the composition of the combustion gases depending on temperature.
Solvation free energies and solvent force constants
International Nuclear Information System (INIS)
Fonseca, T.; Ladanyi, B.M.; Hynes, J.T.
1992-01-01
A theoretical formulation for the solvent force constant k q , which gauges electrical potential fluctuations for an ion in solution and whose charge dependence is a measure of nonlinear aspects of solvation, is presented in terms of the solute charge (q) variation of the solvation free energy. This formulation allows the calculation of k q via integral equation theories. This is illustrated by a series of calculations for ionic solutes in model dipolar-quadrupolar solvents via the reference hypernetted chain (RHNC) integral equation approach. It is found that the q variation of k q can be comprehended in terms of the cooperative (or competing) contributions of the solvent dipole and quadrupole to the acceleration of the solvation free energy. By contrast, traditional notions of dielectric saturation prove to be of much less direct relevance, due in part to the importance of competing electrostriction effects. The formalism is also applied to available simulation and integral equation solvation free energy studies of aqueous ionic solvation to infer to behavior of k q . The extensions for the formalism to more complex solutes (e.g., ion pairs), to higher order fluctuations (e.g., electric field), and to the solvent frequency and effective mass are briefly indicated. 51 refs., 11 figs., 1 tab
Relativistic motion in a constant electromagnetic field
International Nuclear Information System (INIS)
Chin, Siu A.
2009-01-01
For a relativistic charged particle moving in a constant electromagnetic field, its velocity 4-vector has been well studied. However, despite the fact that both the electromagnetic field and the equations of motion are purely real, the resulting 4-velocity is seemingly due to a complex electromagnetic field. This work shows that this is not due to some complex formalism used (such as Clifford algebra) but is intrinsically due to the fact that the o(3,1) Lie algebra of the Lorentz group is equivalent to two commuting complex su(2) algebras. Expressing the complex su(2) generators in terms of the boost and rotation operators then naturally introduces a complex electromagnetic field. This work solves the equation of motion not as a matrix equation, but as an operator evolution equation in terms of the generators of the Lorentz group. The factorization of the real evolution operator into two commuting complex evolution operators then directly gives the time evolution of the velocity 4-vector without any reference to an intermediate field
The Constant Comparative Method of Qualitative Analysis
Directory of Open Access Journals (Sweden)
Barney G. Glaser, Ph.D.
2008-11-01
Full Text Available Currently, the general approaches to the analysis of qualitative data are these:1. If the analyst wishes to convert qualitative data into crudely quantifiable form so that he can provisionally test a hypothesis, he codes the data first and then analyzes it. He makes an effort to code “all relevant data [that] can be brought to bear on a point,” and then systematically assembles, assesses and analyzes these data in a fashion that will “constitute proof for a given proposition.”i2. If the analyst wishes only to generate theoretical ideasnew categories and their properties, hypotheses and interrelated hypotheses- he cannot be confined to the practice of coding first and then analyzing the data since, in generating theory, he is constantly redesigning and reintegrating his theoretical notions as he reviews his material.ii Analysis with his purpose, but the explicit coding itself often seems an unnecessary, burdensome task. As a result, the analyst merely inspects his data for new properties of his theoretical categories, and writes memos on these properties.We wish to suggest a third approach
Determination of a dielectric waveguide propagation constant using a multifilament-current model.
Cory, H; Altman, Z; Leviatan, Y
1989-09-15
A moment method using a multifilament-current model is presented to analyze the modes propagating in a cylindrical dielectric waveguide. In this model, analytically derivable fields of filamentary electric and magnetic currents (of yet unknown propagation constant and amplitude) are used to simulate the field of each mode inside and outside the guiding core. A simple point-matching procedure is subsequently used to enforce the boundary conditions at the core periphery and results in a homogeneous matrix equation. The longitudinal propagation constant of each mode and the currents that yield the field distribution of this mode are then found by solving this equation. As an example, a circular dielectric waveguide is analyzed and the results are presented.
Dutta, Samrat; Patchaikani, Prem Kumar; Behera, Laxmidhar
2016-07-01
This paper presents a single-network adaptive critic-based controller for continuous-time systems with unknown dynamics in a policy iteration (PI) framework. It is assumed that the unknown dynamics can be estimated using the Takagi-Sugeno-Kang fuzzy model with arbitrary precision. The successful implementation of a PI scheme depends on the effective learning of critic network parameters. Network parameters must stabilize the system in each iteration in addition to approximating the critic and the cost. It is found that the critic updates according to the Hamilton-Jacobi-Bellman formulation sometimes lead to the instability of the closed-loop systems. In the proposed work, a novel critic network parameter update scheme is adopted, which not only approximates the critic at current iteration but also provides feasible solutions that keep the policy stable in the next step of training by combining a Lyapunov-based linear matrix inequalities approach with PI. The critic modeling technique presented here is the first of its kind to address this issue. Though multiple literature exists discussing the convergence of PI, however, to the best of our knowledge, there exists no literature, which focuses on the effect of critic network parameters on the convergence. Computational complexity in the proposed algorithm is reduced to the order of (Fz)(n-1) , where n is the fuzzy state dimensionality and Fz is the number of fuzzy zones in the states space. A genetic algorithm toolbox of MATLAB is used for searching stable parameters while minimizing the training error. The proposed algorithm also provides a way to solve for the initial stable control policy in the PI scheme. The algorithm is validated through real-time experiment on a commercial robotic manipulator. Results show that the algorithm successfully finds stable critic network parameters in real time for a highly nonlinear system.
Estimation of expiratory time constants via fuzzy clustering
M.S. Lourens (M.S.); L. Ali (Lejla); B.W. van den Berg (Bart); A.F.M. Verbraak (Anton); J.M. Bogaard (Jan); H.C. Hoogsteden (Henk); R. Babuška (R.)
2001-01-01
markdownabstractObjective. In mechanically ventilated patients the expiratorytime constant provides information about respiratory mechanics. In thepresent study a new method, fuzzy clustering, is proposed to determine expiratory time constants. Fuzzy clustering differs from other methods since it
Wheatstone bridge fed from a bilateral constant current source.
Velayudhan, C; Oommen, D
1980-03-01
A simple inexpensive scheme of an electronic amplifier for Wheatstone bridge application is presented. The bridge is excited from a bilateral constant current square wave source. The advantage of constant current drive is presented.
Stunt Barbie - A Laboratory Practicum Combining Constant Velocity and Constant Acceleration
Hertting, Scott
2011-04-01
In preparing to teach the advanced physics course at my high school, I found it useful to work through the end-of-chapter problems in the book used by the advanced class. A problem on motion in one dimension involved a stunt woman in free fall from a tree limb onto a horse running beneath her.2 The problem presents a connected learning opportunity for students because it requires the use of the constant velocity model xf = v*t + xi and the constant acceleration model yf = ½* g* t2 + vyi* t + yi (where g = 9.8 m/s/s) to solve it. I named the stunt woman Barbie and created an activity titled "Stunt Barbie."
"Known Unknowns": Current Questions in Muscle Satellite Cell Biology.
Cornelison, Ddw
2018-01-01
Our understanding of satellite cells, now known to be the obligate stem cells of skeletal muscle, has increased dramatically in recent years due to the introduction of new molecular, genetic, and technical resources. In addition to their role in acute repair of damaged muscle, satellite cells are of interest in the fields of aging, exercise, neuromuscular disease, and stem cell therapy, and all of these applications have driven a dramatic increase in our understanding of the activity and potential of satellite cells. However, many fundamental questions of satellite cell biology remain to be answered, including their emergence as a specific lineage, the degree and significance of heterogeneity within the satellite cell population, the roles of their interactions with other resident and infiltrating cell types during homeostasis and regeneration, and the relative roles of intrinsic vs extrinsic factors that may contribute to satellite cell dysfunction in the context of aging or disease. This review will address the current state of these open questions in satellite cell biology. © 2018 Elsevier Inc. All rights reserved.
The fine-structure constant before quantum mechanics
Kragh, H
2003-01-01
This paper focuses on the early history of the fine-structure constant, largely the period until 1925. Contrary to what is generally assumed, speculations concerning the interdependence of the elementary electric charge and Planck's constant predated Arnold Sommerfeld's 1916 discussion of the dimensionless constant. This paper pays particular attention to a little known work from 1914 in which G N Lewis and E Q Adams derived what is effectively a numerical expression for the fine-structure constant.
International Nuclear Information System (INIS)
2001-12-01
This report contains translations of seven papers published in the Nuclear Constants journal (Voprosy Atomnoj Nauki I Teknniki, seriya: Yadernye Konstanty (YK), vypusk 1, 2000). They are marked as 'Translated from Russian'. Two original papers published in YK in English are included with correction of found misprints and small format changes. As a result the report contains all papers presented in YK, 1 (2000). (author)
International Nuclear Information System (INIS)
2002-12-01
This report contains translations of eight papers published in the Nuclear Constants journal (Voprosy Atomnoj Nauki I Teknniki, seriya: Yadernye Konstanty (YK), vypusk 1, 2001). They are marked as 'Translated from Russian'. Six original papers published in YK in English are included with correction of found misprints and small format changes. As a result the report contains all papers presented in YK, 1 (2001). (author)
low cost constant low cost constant – head drip irrigation emitter
African Journals Online (AJOL)
eobe
constant – head drip system on the other hand for a 25 m2 plot size was N 15, 870 ($79) at a current exchange rate of N210 to $1(US), further evaluation also revealed that the system can be extended to irrigate up to 100 m2 by raising the barrel to a height of 1 m above the ground, this will serve 560 maize crop stands. This.
Constants, context, and change: the pursuit of purpose*
Lemkau, Henry L.
2008-01-01
Purpose: This lecture addresses the history and philosophy of librarianship, in general, and medical librarianship, in particular. The author discusses the profession and attempts to set its place in the context of the social and cultural worlds in which we function and in the context of the professions which we serve. Discussion: Goals are identified that are common and immutable. Examined are the changing methods by which we meet these ends, particularly the impact of technology and other factors on how we function now and in the future. Change itself is identified as the one constant of which we can be certain. That we strive and achieve is because of a sense of purpose that has guided so many of our profession's leaders. Acknowledging an embarrassment of riches, I point to the achievements of some of the most notable of my colleagues and friends, as examples of what such an extraordinary dedication to the pursuit of purpose makes possible. Conclusions: So long as we maintain this pursuit of purpose, which is, as Estelle Brodman said of the pursuit of excellence, a statement of faith in ourselves, our future is secure. PMID:18219376
Constants, context, and change: the pursuit of purpose.
Lemkau, Henry L
2008-01-01
This lecture addresses the history and philosophy of librarianship, in general, and medical librarianship, in particular. The author discusses the profession and attempts to set its place in the context of the social and cultural worlds in which we function and in the context of the professions which we serve. Goals are identified that are common and immutable. Examined are the changing methods by which we meet these ends, particularly the impact of technology and other factors on how we function now and in the future. Change itself is identified as the one constant of which we can be certain. That we strive and achieve is because of a sense of purpose that has guided so many of our profession's leaders. Acknowledging an embarrassment of riches, I point to the achievements of some of the most notable of my colleagues and friends, as examples of what such an extraordinary dedication to the pursuit of purpose makes possible. So long as we maintain this pursuit of purpose, which is, as Estelle Brodman said of the pursuit of excellence, a statement of faith in ourselves, our future is secure.
Stability constant of the trisglycinto metal complexes | Na'aliya ...
African Journals Online (AJOL)
The stability constants of iron, manganese, cobalt, and nickel complexes of glycine have been determined in aqueous solution by potentiometric titration with standard sodium hydroxide solution. The values of the stepwise stability constants were obtained by ORIGIN '50' program. The overall stability constants of the ...
Nuclear magnetic resonance J coupling constant polarizabilities of hydrogen peroxide
DEFF Research Database (Denmark)
Kjær, Hanna; Nielsen, Monia R.; Pagola, Gabriel I.
2012-01-01
In this paper we present the so far most extended investigation of the calculation of the coupling constant polarizability of a molecule. The components of the coupling constant polarizability are derivatives of the NMR indirect nuclear spin-spin coupling constant with respect to an external elec...
Determination of optical constants and nonlinear optical coefficients ...
Indian Academy of Sciences (India)
The optical properties of Violet 1-doped polyvinyl alcohol (PVA) have been investigated using Wemble and Didomenico (WD) method. The optical constants such as refractive index , the dispersion energy , the oscillation energy 0, the lattice dielectric constant ∞, light frequency dielectric constant 0 and the ratio of ...
Garbage-free reversible constant multipliers for arbitrary integers
DEFF Research Database (Denmark)
Mogensen, Torben Ægidius
2013-01-01
We present a method for constructing reversible circuitry for multiplying integers by arbitrary integer constants. The method is based on Mealy machines and gives circuits whose size are (in the worst case) linear in the size of the constant. This makes the method unsuitable for large constants...
Towards Grothendieck constants and LHV models in quantum mechanics
International Nuclear Information System (INIS)
Hua, Bobo; Li, Ming; Zhang, Tinggui; Zhou, Chunqin; Li-Jost, Xianqing; Fei, Shao-Ming
2015-01-01
We adopt a continuous model to estimate the Grothendieck constants. An analytical formula to compute the lower bounds of Grothendieck constants has been explicitly derived for arbitrary orders, which improves previous bounds. Moreover, our lower bound of the Grothendieck constant of order three gives a refined bound of the threshold value for the nonlocality of the two-qubit Werner states. (paper)
Reliability concerns with logical constants in Xilinx FPGA designs
Energy Technology Data Exchange (ETDEWEB)
Quinn, Heather M [Los Alamos National Laboratory; Graham, Paul [Los Alamos National Laboratory; Morgan, Keith [Los Alamos National Laboratory; Ostler, Patrick [Los Alamos National Laboratory; Allen, Greg [JPL; Swift, Gary [XILINX; Tseng, Chen W [XILINX
2009-01-01
In Xilinx Field Programmable Gate Arrays logical constants, which ground unused inputs and provide constants for designs, are implemented in SEU-susceptible logic. In the past, these logical constants have been shown to cause the user circuit to output bad data and were not resetable through off-line rcconfiguration. In the more recent devices, logical constants are less problematic, though mitigation should still be considered for high reliability applications. In conclusion, we have presented a number of reliability concerns with logical constants in the Xilinx Virtex family. There are two main categories of logical constants: implicit and explicit logical constants. In all of the Virtex devices, the implicit logical constants are implemented using half latches, which in the most recent devices are several orders of magnitudes smaller than configuration bit cells. Explicit logical constants are implemented exclusively using constant LUTs in the Virtex-I and Virtex-II, and use a combination of constant LUTs and architectural posts to the ground plane in the Virtex-4. We have also presented mitigation methods and options for these devices. While SEUs in implicit and some types of explicit logical constants can cause data corrupt, the chance of failure from these components is now much smaller than it was in the Virtex-I device. Therefore, for many cases, mitigation might not be necessary, except under extremely high reliability situations.
Stability constants of the Europium complexes with the chloride ions
International Nuclear Information System (INIS)
Jimenez R, M.; Solache R, M.; Rojas H, A.
2000-01-01
The stability constants of lanthanides complexes with chloride ions which were determined at the same ionic force but in different media, are significantly different. It does not exist a systematic study over these stability constants. The purpose of this work is to determine the stability constants of the europium complexes with chloride ions at 303 K, by the solvents extraction method. (Author)
An automated approach for finding variable-constant pairing bugs
DEFF Research Database (Denmark)
Lawall, Julia; Lo, David
2010-01-01
operating systems provide little support for checking the usage of named constants. This affects correctness, when a constant is used in a context where its value is meaningless, and software maintenance, when a constant has the right value for its usage context but the wrong name. We propose a hybrid...
Constant False Alarm Rate (CFAR) Autotrend Evaluation Report
2011-12-01
TECHNICAL REPORT RDMR-AE-11-01 CONSTANT FALSE ALARM RATE ( CFAR ) AUTOTREND EVALUATION REPORT Daniel Wade Aviation Engineering...TYPE AND DATES COVERED Final 4. TITLE AND SUBTITLE Constant False Alarm Rate ( CFAR ) Autotrend Evaluation Report 5. FUNDING NUMBERS...performance of the Constant False Alarm Rate ( CFAR ) Autotrend dynamic alert detection technology as an augmentation to the Apache Modernized Signal
Determination and stability constants of Manganese (II) amino acid ...
African Journals Online (AJOL)
Determination and stability constants of Manganese (II) amino acid complexes. HN Aliyu, J Na'aliya. Abstract. The stepwise and the overall stability constants of the complexes formed by manganese (II) ion and twelve (12) amino acids have been determined. The dissociation constants, pKa, of the amino acids determined ...
DFT computations of the lattice constant, stable atomic structure and ...
African Journals Online (AJOL)
This paper presents the most stable atomic structure and lattice constant of Fullerenes (C60). FHI-aims DFT code was used to predict the stable structure and the computational lattice constant of C60. These were compared with known experimental structures and lattice constants of C60. The results obtained showed that ...
Organization of Control Units with Operational Addressing
Alexander A. Barkalov; Roman M. Babakov; Larysa A. Titarenko
2012-01-01
The using of operational addressing unit as the block of control unit is proposed. The new structure model of Moore finite-state machine with reduced hardware amount is developed. The generalized structure of operational addressing unit is suggested. An example of synthesis process for Moore finite-state machine with operational addressing unit is given. The analytical researches of proposed structure of control unit are executed.
Novel Duplicate Address Detection with Hash Function.
Directory of Open Access Journals (Sweden)
GuangJia Song
Full Text Available Duplicate address detection (DAD is an important component of the address resolution protocol (ARP and the neighbor discovery protocol (NDP. DAD determines whether an IP address is in conflict with other nodes. In traditional DAD, the target address to be detected is broadcast through the network, which provides convenience for malicious nodes to attack. A malicious node can send a spoofing reply to prevent the address configuration of a normal node, and thus, a denial-of-service attack is launched. This study proposes a hash method to hide the target address in DAD, which prevents an attack node from launching destination attacks. If the address of a normal node is identical to the detection address, then its hash value should be the same as the "Hash_64" field in the neighboring solicitation message. Consequently, DAD can be successfully completed. This process is called DAD-h. Simulation results indicate that address configuration using DAD-h has a considerably higher success rate when under attack compared with traditional DAD. Comparative analysis shows that DAD-h does not require third-party devices and considerable computing resources; it also provides a lightweight security resolution.
IP Address Management Principles and Practice
Rooney, Timothy
2010-01-01
This book will be the first covering the subject of IP address management (IPAM). The practice of IPAM includes the application of network management disciplines to IP address space and associated network services, namely DHCP (Dynamic Host Configuration Protocol) and DNS (Domain Name System). The consequence of inaccurately configuring DHCP is that end users may not be able to obtain IP addresses to access the network. Without proper DNS configuration, usability of the network will greatly suffer as the name-to-address lookup process may fail. Imagine having to navigate to a website or send a
The cosmological constant in theories with finite spacetime
International Nuclear Information System (INIS)
Kummer, Janis
2014-08-01
We study the role of the cosmological constant in different theories with finite spacetime. The cosmological constant appears both as an initial condition and as a constant of integration. In the context of the cosmological constant problem a new model will be presented. This modification of general relativity generates a small, non-vanishing cosmological constant, which is radiatively stable. The dynamics of the expansion of the universe in this model will be analyzed. Eventually, we try to solve the emergent problems concerning the generation of accelerated expansion using a quintessence model of dark energy.
DEFF Research Database (Denmark)
Álvarez-Asencio, R.; Thormann, Esben; Rutland, M.W.
2013-01-01
A technique has been developed for the calculation of torsional spring constants for AFM cantilevers based on the combination of the normal spring constant and plate/beam theory. It is easy to apply and allow the determination of torsional constants for stiff cantilevers where the thermal power...
Multiple constant multiplication optimizations for field programmable gate arrays
Kumm, Martin
2016-01-01
This work covers field programmable gate array (FPGA)-specific optimizations of circuits computing the multiplication of a variable by several constants, commonly denoted as multiple constant multiplication (MCM). These optimizations focus on low resource usage but high performance. They comprise the use of fast carry-chains in adder-based constant multiplications including ternary (3-input) adders as well as the integration of look-up table-based constant multipliers and embedded multipliers to get the optimal mapping to modern FPGAs. The proposed methods can be used for the efficient implementation of digital filters, discrete transforms and many other circuits in the domain of digital signal processing, communication and image processing. Contents Heuristic and ILP-Based Optimal Solutions for the Pipelined Multiple Constant Multiplication Problem Methods to Integrate Embedded Multipliers, LUT-Based Constant Multipliers and Ternary (3-Input) Adders An Optimized Multiple Constant Multiplication Architecture ...
Approaches for Resolving Dynamic IP Addressing.
Foo, Schubert; Hui, Siu Cheung; Yip, See Wai; He, Yulan
1997-01-01
A problem with dynamic Internet protocol (IP) addressing arises when the Internet connection is through an Internet provider since the IP address is allocated only at connection time. This article examines a number of online and offline methods for resolving the problem. Suggests dynamic domain name system (DNS) and directory service look-up are…
16 CFR 1000.4 - Commission address.
2010-01-01
... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Commission address. 1000.4 Section 1000.4 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION GENERAL COMMISSION ORGANIZATION AND FUNCTIONS § 1000.4 Commission address. The principal Offices of the Commission are at 4330 East West Highway...
37 CFR 251.1 - Official addresses.
2010-07-01
... Express, United Parcel Service and similar corporate courier services), use the following address... through the U.S. Postal Service, use the following address: Copyright Arbitration Royalty Panel, P.O. Box 70977, Southwest Station, Washington, DC 20024-0977. (d) Federal Express, United Parcel Service and...
Decreased kidney function of unknown cause in Nicaragua: a community-based survey.
Torres, Cecilia; Aragón, Aurora; González, Marvin; López, Indiana; Jakobsson, Kristina; Elinder, Carl-Gustaf; Lundberg, Ingvar; Wesseling, Catharina
2010-03-01
End-stage kidney disease overwhelms health services in Central America. We determined prevalences of decreased kidney function in distinct populations in the most affected region of Nicaragua. Cross-sectional survey. Total populations aged 20-60 years of 5 villages in Northwest Nicaragua: mining/subsistence farming (elevation, 100-300 m above sea level), banana/sugarcane (100-300 m), fishing (0-100 m), services (0-100 m), and coffee (200-675 m); 479 men and 617 women (83% response). Village; participant sex, age, and occupation; conventional chronic kidney disease risk factors. Serum creatinine (SCr) values greater than laboratory reference range for sex, estimated glomerular filtration rate 300 mg/dL) range. Prevalences of abnormal SCr levels: 18% (of all men) and 5% (of all women); in the mining/subsistence farming village, 26% and 7%; banana/sugarcane, 22% and 6%; fishing, 13% and 4%; services, 0% and 1%; and coffee, 7% and 0%. Prevalences of estimated glomerular filtration rate banana/sugarcane and mining/subsistence farming villages, high blood pressure and age were significant predictors of abnormal SCr levels in men, and for mining/subsistence farming, age in women. Causality is not addressed. In some Nicaraguan villages and population segments, men in particular show a high prevalence of decreased kidney function of unknown origin, possibly environmental or occupational. Copyright 2010 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
Detecting Unknown Attacks in Wireless Sensor Networks That Contain Mobile Nodes
Directory of Open Access Journals (Sweden)
Zorana Banković
2012-08-01
Full Text Available As wireless sensor networks are usually deployed in unattended areas, security policies cannot be updated in a timely fashion upon identification of new attacks. This gives enough time for attackers to cause significant damage. Thus, it is of great importance to provide protection from unknown attacks. However, existing solutions are mostly concentrated on known attacks. On the other hand, mobility can make the sensor network more resilient to failures, reactive to events, and able to support disparate missions with a common set of sensors, yet the problem of security becomes more complicated. In order to address the issue of security in networks with mobile nodes, we propose a machine learning solution for anomaly detection along with the feature extraction process that tries to detect temporal and spatial inconsistencies in the sequences of sensed values and the routing paths used to forward these values to the base station. We also propose a special way to treat mobile nodes, which is the main novelty of this work. The data produced in the presence of an attacker are treated as outliers, and detected using clustering techniques. These techniques are further coupled with a reputation system, in this way isolating compromised nodes in timely fashion. The proposal exhibits good performances at detecting and confining previously unseen attacks, including the cases when mobile nodes are compromised.
Datta, Bithin; Chakrabarty, Dibakar; Dhar, Anirban
2009-09-01
Pollution source identification is a common problem encountered frequently. In absence of prior information about flow and transport parameters, the performance of source identification models depends on the accuracy in estimation of these parameters. A methodology is developed for simultaneous pollution source identification and parameter estimation in groundwater systems. The groundwater flow and transport simulator is linked to the nonlinear optimization model as an external module. The simulator defines the flow and transport processes, and serves as a binding equality constraint. The Jacobian matrix which determines the search direction in the nonlinear optimization model links the groundwater flow-transport simulator and the optimization method. Performance of the proposed methodology using spatiotemporal hydraulic head values and pollutant concentration measurements is evaluated by solving illustrative problems. Two different decision model formulations are developed. The computational efficiency of these models is compared using two nonlinear optimization algorithms. The proposed methodology addresses some of the computational limitations of using the embedded optimization technique which embeds the discretized flow and transport equations as equality constraints for optimization. Solution results obtained are also found to be better than those obtained using the embedded optimization technique. The performance evaluations reported here demonstrate the potential applicability of the developed methodology for a fairly large aquifer study area with multiple unknown pollution sources.
Directory of Open Access Journals (Sweden)
Jussara Bertho Fantinatti
2007-01-01
Full Text Available This work aimed to analyse Eucalyptus grandis W.Hill ex Maiden seed behaviour, under controlled deterioration, and to estimate viability equation constants for the species. Seeds were harvested in the growing season of 1999, and the moisture contents were adjusted from 11.3% to a range between 1.2 and 18.1% at 25ºC. The subsamples were sealed into laminate aluminium-foil packets, for storage in incubators at 40, 50 and 65±0.5ºC. The seeds presented orthodox performance, in which the constants for predicting seed longevity of E. grandis were K E = 9.661, C W = 6.467, C H = 0.03498 and C Q = 0.0002330. The usual and inverse relationship between water content and seed longevity was also observed. The lowest moisture content limit for application of the viability equation at 65ºC was 4.9%, estimated under hygroscopic equilibrium with 23% of relative humidity in the storage environment.Este trabalho teve como objetivos verificar o desempenho de sementes de Eucalyptus grandis W.Hill ex Maiden, após a deterioração em condições controladas, e obter as constantes da equação de viabilidade. As sementes foram colhidas na safra de 1999, e a umidade foi ajustada de 11,3% para valores entre 1,2 e 18,1% a 25ºC As subamostras foram acondicionadas em embalagens de alumínio termossoldadas, armazenadas a 40, 50 e 65±0,5ºC. As sementes apresentaram um desempenho ortodoxo em relação ao armazenamento. As constantes para a predição da longevidade foram K E = 9,661, C W = 6,467, C H = 0,03498 e C Q = 0,0002330. Foi observada a relação inversa entre teor de água e longevidade. O limite inferior de grau de umidade, calculado para aplicação da equação a 65ºC, foi de 4,9%, estimativa obtida sob equilíbrio higroscópico com umidade relativa de 23% no ambiente de armazenamento.
Birngruber, Christoph G; Görner, Nicole; Ramsthaler, H Frank
2016-01-01
The number of tattooed people in Germany has constantly grown over the past few years. The present study deals with the question if this social trend can be seen in foren- sic autopsy cases as well. In a retrospective study, forensic autopsy cases of two periods (1990-1994 and 2010-2014) have been reviewed and statistically analyzed. Comparison of the two periods revealed a significant increase in tattooed individuals, especially in the female subgroup. Between 2010 and 2014, 14.2 % of the deceased showed tattoos. There are significant differences in the frequency and localization of tattoos dependent on age and sex. About 50 % of the tattooed deceased showed tattoos on body sites that are visible for other persons in everyday life. The resulting value of tattoos for the purpose of identifying unknown bodies is discussed and illustrated.
Stella, Giulia M; Benvenuti, Silvia; Gentile, Alessandra; Comoglio, Paolo M
2017-10-01
The molecular and cellular mechanisms which drive metastatic spread are the topic of constant debate and scientific research due to the potential implications for cancer patients' prognosis. In addition to genetics and environmental factors, mechanics of single cells and physical interaction with the surrounding environment play relevant role in defining invasive phenotype. Reconstructing the physical properties of metastatic clones may help to clarify still open issues in disease progression as well as to lead to new diagnostic and therapeutic approaches. In this perspective cancer of unknown primary origin (CUP) identify the ideal model to study physical interactions and forces involved in the metastatic process. We have previously demonstrated that MET oncogene is mutated with unexpected high frequency in CUPs. We here analyze and discuss how the MET activation by somatic mutation may affect physical properties in giving rise to such a highly malignant syndrome, as that defined by CUP. Copyright © 2017. Published by Elsevier B.V.
Amami, P; Mascia, M M; Franzini, A; Saba, F; Albanese, A
2017-08-01
The study aimed to evaluate safety and efficacy of shifting stimulation settings from constant-voltage (CV) to constant-current (CC) programming in patients with Parkinson's disease (PD) and chronic subthalamic nucleus deep brain stimulation (STN DBS). Twenty PD patients with chronic STN DBS set in CV programming were shifted to CC and followed for 3 months; the other stimulation settings and the medication regimen remained unchanged. Side effects, motor, non-motor, executive functions, and impedance were assessed at baseline and during follow-up. No adverse events were observed at time of shifting or during CC stimulation. Motor and non-motor measures remained unchanged at follow-up despite impedance decreased. Compared to baseline, inhibition processes improved at follow-up. The shifting strategy was well tolerated and the clinical outcome was maintained with no need to adjust stimulation settings or medications notwithstanding a decrease of impedance. Improvement of inhibition processes is a finding which needed further investigation.
Addressing employee turnover and retention: keeping your valued performers.
McConnell, Charles R
2011-01-01
Employee turnover and employee retention are inextricably linked; to control turnover is to enhance retention. Turnover is a relatively simple concept; however, considerable confusion often results when addressing turnover because of differences in how it is defined; that is, what is counted, how it is counted, and how the turnover rates are expressed. Turnover is also costly, although not enough attention is paid to its cost because so much of it is indirect and thus not readily visible. There are a variety of causes of turnover, some that can be corrected and some that cannot be avoided. Reducing or otherwise controlling turnover requires continuing management attention to its causes and constant recognition of what can and should be controlled and what cannot be controlled. Ongoing attention to turnover is an essential part of the department manager's role; every improvement in turnover is a direct improvement in retention, with eventual positive effects on the bottom line.
Local address and emergency contact details
2013-01-01
The HR Department would like to remind members of the personnel that they are responsible for ensuring that their personal data concerning local address and preferred emergency contact details remains valid and up-to-date. Both are easily accessible via the links below: Local address: https://edh.cern.ch/Document/Personnel/LocalAddressChange Emergency contacts: https://edh.cern.ch/Document/Personnel/EC Please take a few minutes to check your details and modify if necessary. Thank you in advance. HR Department Head Office
Fu, Yue; Chai, Tianyou
2016-12-01
Regarding two-player zero-sum games of continuous-time nonlinear systems with completely unknown dynamics, this paper presents an online adaptive algorithm for learning the Nash equilibrium solution, i.e., the optimal policy pair. First, for known systems, the simultaneous policy updating algorithm (SPUA) is reviewed. A new analytical method to prove the convergence is presented. Then, based on the SPUA, without using a priori knowledge of any system dynamics, an online algorithm is proposed to simultaneously learn in real time either the minimal nonnegative solution of the Hamilton-Jacobi-Isaacs (HJI) equation or the generalized algebraic Riccati equation for linear systems as a special case, along with the optimal policy pair. The approximate solution to the HJI equation and the admissible policy pair is reexpressed by the approximation theorem. The unknown constants or weights of each are identified simultaneously by resorting to the recursive least square method. The convergence of the online algorithm to the optimal solutions is provided. A practical online algorithm is also developed. Simulation results illustrate the effectiveness of the proposed method.
Occupational therapy students' views on addressing sexual health.
Areskoug-Josefsson, Kristina; Fristedt, Sofi
2017-12-22
Sexual health is an important issue in daily life, but little is known about occupational therapy (OT) students' views on these matters. To explore occupational therapy students' views on addressing sexual health in their future professional role. A descriptive qualitative study involving 37 OT students in 5 focus groups was performed and analyzed using content analysis. Three categories: 'Sexual health is part of occupational therapy and but not of the OT educational program'; 'Need for knowledge to identify and intervene related to sexual health problems'; and finally, 'Communication about sexual health-unknown, untried, but necessary', formed the theme, 'Willing to try, wanting to know more, and recognizing not only the difficulties and challenges but also the importance of sexual health in OT practice'. OT-students consider sexual health as part of OT-practice, but experience lack of knowledge of sexual health related to disease/disability, cultural diversity, and age and sexual orientation. Educational programs need to cover these matters, including how to address sexual health in OT-practice, to enhance OT's future competence related to promotion of sexual health for clients. Knowledge on students' views are vital to guide education on this important, rather neglected, area.
Biodiversity and global health—hubris, humility and the unknown
Stephens, Carolyn
2012-03-01
biodiversity and well-being; and the links of biodiversity to the green economy in the context of sustainable development and poverty alleviation. References [1] Schuiteman A et al 2011 Nocturne for an unknown pollinator: first description of a night-flowering orchid (Bulbophyllum nocturnum) Bot. J. Linean Soc. 167 344-50 [2] Kinver M and Gill V 2011 Botanists discover 'remarkable' night-flowering orchid BBC News Science and Environment (www.bbc.co.uk/news/science-environment-15818662) [3] Rudd M A 2011 Scientists' opinions on the global status and management of biological diversity Conserv. Biol. 25 1165-75 [4] Bottrill M C et al 2008 Is conservation triage just smart decision making? Trends Ecol. Evol. 23 649-54 [5] Parr M J et al 2009 Why we should aim for zero extinction Trends Ecol. Evol. 24 181 Bottrill M C et al 2009 Finite conservation funds mean triage is unavoidable Trends Ecol. Evol. 24 183-4 [6] Pushpangadan P and Behl H M 2005 Environment & Biodiversity: Agenda for Future (Lucknow: International Society of Environmental Botanists) (http://isebindia.com/icpep-3/icpep3-s-2.html) [7] Alves R and Rosa I 2007 Biodiversity, traditional medicine and public health: where do they meet? J. Ethnobiol. Ethnomed. 3 14 [8] Center for Biodiversity and Conservation 1997 Biodiversity and Human Health: A Guide for Policymakers (New York: American Museum of Natural History) [9] Chivian E 1997 Global environmental degradation and biodiversity loss: implications for human health Biodiversity and Human Health ed F Grifo and J Rosenthal (Washington, DC: Island) pp 7-38 [10] UNEP-WCMC 2011 Health and Well Being of Communities Directly Dependent on Ecosystem Goods and Services: An Indicator for the Convention on Biological Diversity (Cambridge: UNEP-World Conservation Monitoring Centre) [11] Nettleton C, Stephens C and Bristow F 2007 Utz Wachil: a study of indigenous perceptions of health and environment in five countries Ecohealth 4 461-772 [12] Jones G P et al 2004 Coral decline
VT E911 ESITE geocoder - address points
Vermont Center for Geographic Information — VT E911 ESITE geocoder - address points. VCGI, in collaboration with the VT E911 Board, has created a suite of geocoding services that can be used to batch geocode...
On Riemannian manifolds (Mn, g) of quasi-constant curvature
International Nuclear Information System (INIS)
Rahman, M.S.
1995-07-01
A Riemannian manifold (M n , g) of quasi-constant curvature is defined. It is shown that an (M n , g) in association with other class of manifolds gives rise, under certain conditions, to a manifold of quasi-constant curvature. Some observations on how a manifold of quasi-constant curvature accounts for a pseudo Ricci-symmetric manifold and quasi-umbilical hypersurface are made. (author). 10 refs
Kaon-nucleus scattering and kaon-nuclear coupling constants
International Nuclear Information System (INIS)
Dumbrajs, O.
1979-01-01
Possibilities are examined of obtaining information on kaon-nuclear coupling constants without referring to any specific models. The basis for such a type of analyses is the use of analytic properties of the scattering amplitudes. Particularly useful is the forward dispersion relation for the antisymmetric amplitude. The analysis of the K+- 12 C scattering leads to the conclusion that the corresponding effective coupling constant is significantly larger than the coherent sum of the elementary coupling constants
Temperature dependence of grain boundary free energy and elastic constants
International Nuclear Information System (INIS)
Foiles, Stephen M.
2010-01-01
This work explores the suggestion that the temperature dependence of the grain boundary free energy can be estimated from the temperature dependence of the elastic constants. The temperature-dependent elastic constants and free energy of a symmetric Σ79 tilt boundary are computed for an embedded atom method model of Ni. The grain boundary free energy scales with the product of the shear modulus times the lattice constant for temperatures up to about 0.75 the melting temperature.
The 400-Hertz constant-speed electrical generation systems
Mcclung, R.
1982-01-01
Materials illustrating a presentation on 400 Hz constant speed generation systems are presented. The system features are outlined, components and functioning described, and display graphics illustrated.
An Einstein-Cartan Fine Structure Constant Definition
Directory of Open Access Journals (Sweden)
Stone R. A. Jr.
2010-01-01
Full Text Available The fine structure constant definition given in Stone R.A. Jr. Progress in Physics, 2010, v.1, 11-13 is compared to an Einstein-Cartan fine structure constant definition. It is shown that the Einstein-Cartan definition produces the correct pure theory value, just not the measure value. To produce the measured value, the pure theory Einstein-Cartan fine structure constant requires only the new variables and spin coupling of the fine structure constant definition in [1].
A new method for the determination of unknown neutron fluence for 14.0 MeV
Energy Technology Data Exchange (ETDEWEB)
Malik, Fariha [Physics Reasearch Division, PINSTECH, Nilore, Islamabad (Pakistan)]. E-mail: fariha@pinstech.org.pk; Khan, Ehsan U. [Department of Physics, CIIT, Islamabad (Pakistan); Qureshi, Imtinan [Physics Reasearch Division, PINSTECH, Nilore, Islamabad (Pakistan); Husaini, Syed N. [Physics Reasearch Division, PINSTECH, Nilore, Islamabad (Pakistan); Ahmad, Waqar [Physics Reasearch Division, PINSTECH, Nilore, Islamabad (Pakistan); Rajput, Usman [Physics Reasearch Division, PINSTECH, Nilore, Islamabad (Pakistan); Raza, Qaiser [Applied Physics Division, PINSTECH, Nilore, Islamabad (Pakistan)
2006-11-15
Measuring the correct neutron fluence in various energy intervals in and around the neutron sources is important for the purpose of personnel and environmental neutron dosimetry. In this paper, we present a new method for the measurement of the fluence of mono-energetic neutrons having the energy of 14.0 MeV. The samples exposed to neutrons from the 14.0 MeV neutron generator at PINSTECH with various fluence values ranging from 10{sup 7} to 10{sup 10} n cm{sup -2} were etched for 10 min in 6 N NaOH at 70.0{+-}1.0 {sup o}C and the transmittance of UV radiation was measured using a spectrophotometer. This procedure was repeated 20 times after etching the same sample each time for increasing time intervals till the stage when transmittance reached the constant minimum value. An exponential decay of the transmittance has been observed with respect to the increasing etching time interval in each of the samples exposed to various neutron fluence. Further, it has also been observed that there is a linear relationship between the transmittance decay constant and neutron fluence. Hence, the linear graph can be used as a calibration for measuring the unknown fluence of 14.0 MeV neutrons.
Konrad, Andreas; Budini, Francesco; Tilp, Markus
2017-08-01
Static stretching induces acute structural changes of the muscle-tendon unit (MTU) that are related to the intensity or duration of stretching. It has been reported that stretching with a constant torque (CT) leads to greater joint range of motion changes than stretching with a constant angle (CA). Whether or not this difference is due to different structural changes of the MTUs of the lower leg and ankle plantar flexors is not known. Therefore, the purpose of this study was to compare the acute effects of single CA and CT stretching on various muscle and tendon mechanical properties. Seventeen young, healthy volunteers were tested on two separate days using either CT or CA stretching (4 × 30 s each). Before and after stretching, dorsiflexion range of motion (RoM), passive resistive torque (PRT), and maximum voluntary contraction (MVC) were measured with a dynamometer. Ultrasonography of the medial gastrocnemius (GM) muscle-tendon junction (MTJ) displacement allowed us to determine the length changes in the tendon and muscle, respectively, and hence to calculate their stiffness. Maximum dorsiflexion increased while PRT, muscle-tendon stiffness, and muscle stiffness decreased following both CA and CT stretching. There was a greater increase in RoM following CT stretching compared to CA stretching. Moreover, the decline in PRT was greater during CT stretching compared to CA stretching. As expected, several functional adaptations (RoM, PRT) were different between CT and CA stretching due to the higher intensity of CT stretching. However, no structural differences in the adaptations to the stretching modalities could be detected. We suggest that the different functional adaptations between CA and CT stretching are the consequence of different adaptations in the perception of stretch and pain.
South African address standard and initiatives towards an international address standard
CSIR Research Space (South Africa)
Cooper, Antony K
2008-10-01
Full Text Available Various countries and international organizations have address standards or are developing them. An address is needed for many more applications than just postal delivery, such as: goods delivery; connecting utilities; opening bank accounts; voting...
South African address standard and initiatives towards an international address standard.
CSIR Research Space (South Africa)
Cooper, Anthony K
2008-09-01
Full Text Available Various countries and international organizations have address standards or are developing them. An address is needed for many more applications than just postal delivery, such as: goods delivery; connecting utilities; opening bank accounts; voting...
Enter your email-address: how German internet users manage their email addresses
Utz, S.
2004-01-01
Writing E-mail is the most popular Internet activity. Meanwhile, many people have more than one E-mail address. The question how people manage their E-mail addresses, more specifically, whether they use them deliberately for different purposes, is the central question of this paper. E-mail addresses
46 CFR 67.113 - Managing owner designation; address; requirement to report change of address.
2010-10-01
... change of address. The owner of each vessel must designate a managing owner on the Application for...) Whenever the address of the managing owner changes, the managing owner shall notify the Director, National... 46 Shipping 2 2010-10-01 2010-10-01 false Managing owner designation; address; requirement to...
Using Constant Time Delay to Teach Braille Word Recognition
Hooper, Jonathan; Ivy, Sarah; Hatton, Deborah
2014-01-01
Introduction: Constant time delay has been identified as an evidence-based practice to teach print sight words and picture recognition (Browder, Ahlbrim-Delzell, Spooner, Mims, & Baker, 2009). For the study presented here, we tested the effectiveness of constant time delay to teach new braille words. Methods: A single-subject multiple baseline…
Theory of the change of elastic constants by interstitials
International Nuclear Information System (INIS)
Breuer, N.; Dederichs, P.H.; Lehmann, C.; Leibfried, G.; Scholz, A.
1975-01-01
The theory of the change of elastic constants by point-defects, in particular by interstitials, is briefly summarized. The typical effects of spring changes in a defect lattice on the elastic data are discussed qualitatively. Numerical results for the change of elastic constants by self-interstitials and vacancies are given and compared with experimental data for Cu and Al
Dielectric Constants of Irradiated and Carbonated Polymers | Okeke ...
African Journals Online (AJOL)
Using the LC resonance circuit, changes in dielectric constants of irradiated and carbonated polymers as a function of carbon concentration are investigated. Both low and high density polymers are used. Results predict a quadratic increase in the dielectric constant of specimen as the percentage concentration of carbon is ...
Vector-meson-baryon coupling constants in QCD sum rules
Erkol, G.; Timmermans, R.G.E.; Rijken, T.A.
2006-01-01
The external-field quantum chromodynamics (QCD) sum rules method is used to evaluate the coupling constants of the vector mesons rho and omega to the nucleon and the Lambda,Sigma, and Xi baryons. It is shown that these coupling constants as calculated from QCD sum rules are consistent with
Scalar-meson-baryon coupling constants in QCD sum rules
Erkol, G; Timmermans, RGE; Oka, M; Rijken, TA; Rijken, Th.A.
The external-field QCD sum rules method is used to evaluate the coupling constants of the light isoscalar-scalar meson ("sigma" or epsilon) to the Lambda,Sigma, and Xi baryons. It is shown that these coupling constants as calculated from QCD sum rules are consistent with SU(3) flavor relations,
Scalar-meson baryon coupling constants in QCD sum rules
Erkol, G.; Timmermans, R.G.E.; Oka, M.; Rijken, T.A.
2006-01-01
The external-field QCD sum rules method is used to evaluate the coupling constants of the light isoscalar-scalar meson (``sigma'' or ε) to the Lambda,Sigma, and Xi baryons. It is shown that these coupling constants as calculated from QCD sum rules are consistent with SU(3) flavor relations, which
Coupler tuning for constant gradient travelling wave accelerating structures
International Nuclear Information System (INIS)
Guo Xingkun; Ma Yanyun; Wang Xiulong
2013-01-01
The method of the coupler tuning for the constant gradient traveling wave accelerating structure was described and the formula of coupling coefficient p was deduced on the basis of analyzing the existing methods for the constant impedance traveling wave accelerating structures and coupling-cavity chain equivalent circuits. The method and formula were validated by the simulation result by CST and experiment data. (authors)
Elastic constants of diamond from molecular dynamics simulations
International Nuclear Information System (INIS)
Gao Guangtu; Van Workum, Kevin; Schall, J David; Harrison, Judith A
2006-01-01
The elastic constants of diamond between 100 and 1100 K have been calculated for the first time using molecular dynamics and the second-generation, reactive empirical bond-order potential (REBO). This version of the REBO potential was used because it was redesigned to be able to model the elastic properties of diamond and graphite at 0 K while maintaining its original capabilities. The independent elastic constants of diamond, C 11 , C 12 , and C 44 , and the bulk modulus were all calculated as a function of temperature, and the results from the three different methods are in excellent agreement. By extrapolating the elastic constant data to 0 K, it is clear that the values obtained here agree with the previously calculated 0 K elastic constants. Because the second-generation REBO potential was fit to obtain better solid-state force constants for diamond and graphite, the agreement with the 0 K elastic constants is not surprising. In addition, the functional form of the second-generation REBO potential is able to qualitatively model the functional dependence of the elastic constants and bulk modulus of diamond at non-zero temperatures. In contrast, reactive potentials based on other functional forms do not reproduce the correct temperature dependence of the elastic constants. The second-generation REBO potential also correctly predicts that diamond has a negative Cauchy pressure in the temperature range examined
Lattice constant measurement from electron backscatter diffraction patterns
DEFF Research Database (Denmark)
Saowadee, Nath; Agersted, Karsten; Bowen, Jacob R.
2017-01-01
Kikuchi bands in election backscattered diffraction patterns (EBSP) contain information about lattice constants of crystallographic samples that can be extracted via the Bragg equation. An advantage of lattice constant measurement from EBSPs over diffraction (XRD) is the ability to perform local ...
New perovskite-related oxides having high dielectric constant ...
Indian Academy of Sciences (India)
Unknown
30. Ferroelectric oxides have very high dielectric constant (~10,000) but have a high dielectric loss. Materials with reasonably high dielectric constant (>40) and low loss are rare. This has led chemists to take up the challenge to search for ...
Determination of stepwise stabilty constants and Gibb's free energy ...
African Journals Online (AJOL)
The overall stability constants of manganese (II), iron (II), cobalt (II), nickel (II), copper (II), and zinc (II) complexes with proline were determined by potentiometric titration of sodium prolinate with the corresponding salt of the divalent metal in aqueous media. The values of the constants (Logâ) were found to be 19.45, 19.23, ...
Influence of dielectric constant of polymerization medium on ...
Indian Academy of Sciences (India)
Finally, conductivity and ammonia gas-sensing property of the polyaniline film were also studied. Keywords. Dielectric constant; processability; conductivity; gas sensing. 1. Introduction. The dielectric constant is a .... tion the green colour emerges and only at a 1:1 volume. Figure 1. Capacitance change of different solvent ...
Performance of Automotive SLI Battery under Constant Current ...
African Journals Online (AJOL)
In this project, a cost-effective 12V battery charge controller was developed to implement constant current constant voltage charge algorithm in small-sized stand-alone solar PV systems. The algorithm was tested on automotive SLI battery instead of deep-cycle PV battery to further reduce overall system cost. The battery ...
Vector and axial constants of the baryon decuplet
International Nuclear Information System (INIS)
Belyaev, V.M.; Blok, B.Y.; Kogan, Y.I.
1985-01-01
On the basis of the QCD sum rules for the polarization operator in external axial and vector fields we determine the vector and axial transition constants in the 3/2 + baryon decuplet. We show that the renormalization of the axial constant is due to the interaction of the external axial field with the quark condensate
Fundamental Constants in Physics and their Time Dependence
CERN. Geneva
2008-01-01
In the Standard Model of Particle Physics we are dealing with 28 fundamental constants. In the experiments these constants can be measured, but theoretically they are not understood. I will discuss these constants, which are mostly mass parameters. Astrophysical measurements indicate that the finestructure constant is not a real constant, but depends on time. Grand unification then implies also a time variation of the QCD scale. Thus the masses of the atomic nuclei and the magnetic moments of the nuclei will depend on time. I proposed an experiment, which is currently done by Prof. Haensch in Munich and his group. The first results indicate a time dependence of the QCD scale. I will discuss the theoretical implications.
Time variable cosmological constants from the age of universe
International Nuclear Information System (INIS)
Xu Lixin; Lu Jianbo; Li Wenbo
2010-01-01
In this Letter, time variable cosmological constant, dubbed age cosmological constant, is investigated motivated by the fact: any cosmological length scale and time scale can introduce a cosmological constant or vacuum energy density into Einstein's theory. The age cosmological constant takes the form ρ Λ =3c 2 M P 2 /t Λ 2 , where t Λ is the age or conformal age of our universe. The effective equation of state (EoS) of age cosmological constant are w Λ eff =-1+2/3 (√(Ω Λ ))/c and w Λ eff =-1+2/3 (√(Ω Λ ))/c (1+z) when the age and conformal age of universe are taken as the role of cosmological time scales respectively. The EoS are the same as the so-called agegraphic dark energy models. However, the evolution histories are different from the agegraphic ones for their different evolution equations.
Evolving Lorentzian wormholes supported by phantom matter and cosmological constant
International Nuclear Information System (INIS)
Cataldo, Mauricio; Campo, Sergio del; Minning, Paul; Salgado, Patricio
2009-01-01
In this paper we study the possibility of sustaining an evolving wormhole via exotic matter made of phantom energy in the presence of a cosmological constant. We derive analytical evolving wormhole geometries by supposing that the radial tension of the phantom matter, which is negative to the radial pressure, and the pressure measured in the tangential directions have barotropic equations of state with constant state parameters. In this case the presence of a cosmological constant ensures accelerated expansion of the wormhole configurations. More specifically, for positive cosmological constant we have wormholes which expand forever and, for negative cosmological constant we have wormholes which expand to a maximum value and then recollapse. At spatial infinity the energy density and the pressures of the anisotropic phantom matter threading the wormholes vanish; thus these evolving wormholes are asymptotically vacuum Λ-Friedmann models with either open or closed or flat topologies.
Centrally managed unified shared virtual address space
Energy Technology Data Exchange (ETDEWEB)
Wilkes, John
2018-02-13
Systems, apparatuses, and methods for managing a unified shared virtual address space. A host may execute system software and manage a plurality of nodes coupled to the host. The host may send work tasks to the nodes, and for each node, the host may externally manage the node's view of the system's virtual address space. Each node may have a central processing unit (CPU) style memory management unit (MMU) with an internal translation lookaside buffer (TLB). In one embodiment, the host may be coupled to a given node via an input/output memory management unit (IOMMU) interface, where the IOMMU frontend interface shares the TLB with the given node's MMU. In another embodiment, the host may control the given node's view of virtual address space via memory-mapped control registers.
Centrally managed unified shared virtual address space
Wilkes, John
2018-02-13
Systems, apparatuses, and methods for managing a unified shared virtual address space. A host may execute system software and manage a plurality of nodes coupled to the host. The host may send work tasks to the nodes, and for each node, the host may externally manage the node's view of the system's virtual address space. Each node may have a central processing unit (CPU) style memory management unit (MMU) with an internal translation lookaside buffer (TLB). In one embodiment, the host may be coupled to a given node via an input/output memory management unit (IOMMU) interface, where the IOMMU frontend interface shares the TLB with the given node's MMU. In another embodiment, the host may control the given node's view of virtual address space via memory-mapped control registers.
Children with hypercholesterolemia of unknown cause: Value of genetic risk scores.
Sjouke, Barbara; Tanck, Michael W T; Fouchier, Sigrid W; Defesche, Joep C; Hutten, Barbara A; Wiegman, Albert; Kastelein, John J P; Hovingh, G Kees
2016-01-01
Familial hypercholesterolemia (FH) is caused by mutations in LDLR, APOB, or PCSK9, and in a previous study, we identified a causative mutation in these FH genes in 95% (255 of 269) of children with the FH phenotype. It has been hypothesized that a polygenic form of hypercholesterolemia is present in FH patients in whom no mutation is identified in the 3 FH genes. To address whether a polygenic form of hypercholesterolemia, defined as high-weighted effect of low-density lipoprotein cholesterol (LDL-C) raising SNPs expressed as the genetic risk score (GRS), is present in the remaining 14 children. On reassessment of the molecular diagnosis and clinical phenotype, 8 FH kindreds met the criteria for hypercholesterolemia of unknown cause and were included in this study. We calculated a weighted GRS comprising 10 established LDL-C-associated SNPs and the APOE genotype in these index cases and evaluated whether the index cases were characterized by an increased GRS compared to 26 first-degree relatives. Phenotypically affected and unaffected individuals could not be distinguished based on any of the risk scores. In this and our previous study, we show that a causal mutation in LDLR, APOB, and PCSK9 can be identified in almost all children with a definite clinical diagnosis of FH. In the small group of patients without a mutation, we did not observe a higher GRS compared with unaffected relatives, which suggests that the FH phenotype is not caused by the aggregate of LDL-C increasing SNPs. Our data imply that application of the GRS is not instrumental as a diagnostic tool to individually define clinically diagnosed FH patients with polygenic hypercholesterolemia in our study population. Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.
Pesticide exposures and chronic kidney disease of unknown etiology: an epidemiologic review.
Valcke, Mathieu; Levasseur, Marie-Eve; Soares da Silva, Agnes; Wesseling, Catharina
2017-05-23
The main causes of chronic kidney disease (CKD) globally are diabetes and hypertension but epidemics of chronic kidney disease of unknown etiology (CKDu) occur in Central America, Sri Lanka, India and beyond. Althoug also being observed in women, CKDu concentrates among men in agricultural sectors. Therefore, suspicions fell initially on pesticide exposure, but currently chronic heat stress and dehydration are considered key etiologic factors. Responding to persistent community and scientific concerns about the role of pesticides, we performed a systematic review of epidemiologic studies that addressed associations between any indicator of pesticide exposure and any outcome measure of CKD. Of the 21 analytical studies we identified, seven were categorized as with low, ten with medium and four with relatively high explanation value. Thirteen (62%) studies reported one or more positive associations, but four had a low explanation value and three presented equivocal results. The main limitations of both positive and negative studies were unspecific and unquantified exposure measurement ('pesticides'), the cross-sectional nature of most studies, confounding and selection bias. The four studies with stronger designs and better exposure assessment (from Sri Lanka, India and USA) all showed exposure-responses or clear associations, but for different pesticides in each study, and three of these studies were conducted in areas without CKDu epidemics. No study investigated interactions between pesticides and other concommittant exposures in agricultural occupations, in particular heat stress and dehydration. In conclusion, existing studies provide scarce evidence for an association between pesticides and regional CKDu epidemics but, given the poor pesticide exposure assessment in the majority, a role of nephrotoxic agrochemicals cannot be conclusively discarded. Future research should procure assessment of lifetime exposures to relevant specific pesticides and enough power
Evanescent Waveguide Apparatus and Method for Measurement of Dielectric Constant
National Research Council Canada - National Science Library
Tonn, David A
2005-01-01
.... In one embodiment, a metal septum is inserted between two samples of the unknown material to thereby reduce the cross-sectional area of the waveguide aperture by splitting width a of the rectangular waveguide in half...
Content addressable memories in scientific instruments
International Nuclear Information System (INIS)
Lotto, I. de; Golinelli, S.
1975-01-01
The content-addressable-memory feature of a new system designed in these laboratories for non-destructive testing of nuclear reactor pressure vessels based on acoustic emission analysis is presented. The content addressable memory is divided into two parts: the first selects the most frequent events among incoming ones (FES: Frequent Event Selection memory), the second stores the frequent events singled out (FEM: Frequent Event Memory). The statistical behaviour of FES is analyzed, and experimental results are compared with theoretical ones; the model presented proved to be a useful tool in dimensioning the instrument store capacity. (Auth.)
Initiative Addresses Subsurface Energy and Environment Problems
Bodvarsson, Gudmundur S.; Majer, Ernest L.; Wang, Joseph S. Y.; Colwell, Frederick; Redden, George
2006-01-01
Members of the geoscience community are cooperating in conceptualizing fundamental, crosscutting research to address major obstacles to solving energy and environmental problems related to the subsurface, through the SECUREarth initiative, which began in 2004. Addressing problems, such as reliable nuclear waste storage and safe carbon dioxide (CO2) sequestration, are critical to maintaining an economical and safe energy supply and clean environment. A recent workshop in Golden, Colo., helped to further the development of the SECUREarth (Scientific Energy/Environmental Crosscutting Underground Research for Urgent Solutions to Secure the Earth's Future) initiative by identifying the key scientific challenges in the geosciences, as well as to target possible approaches for overcoming roadblocks.
Welfare work addressing immigrants and refugees
DEFF Research Database (Denmark)
Øland, Trine
In this presentation I will discuss the ways in which welfare workers addressing immigrants and refugees (re)produce integrationist visions, symbolizing society as an integrated whole and immigrants/refugees as a distraction to that whole. Paradoxically, welfare workers also oppose...... these integrationist visions in their quest to protect immigrants’ and refugees’ fundamental wellbeing and status as human beings with equal rights, group life and history. These opposing elements generate ambiguity and contradiction within integrationist welfare work. The ambition of the presentation is to enquire......, nurses and more) addressing immigrants and refugees and their families and descendants in the Danish welfare nation-state....
Addressing techniques of liquid crystal displays
Ruckmongathan, Temkar N
2014-01-01
Unique reference source that can be used from the beginning to end of a design project to aid choosing an appropriate LCD addressing technique for a given application This book will be aimed at design engineers who are likely to embed LCD drivers and controllers in many systems including systems on chip. Such designers face the challenge of making the right choice of an addressing technique that will serve them with best performance at minimal cost and complexity. Readers will be able to learn about various methods available for driving matrix LCDs and the comparisons at the end of each chap
Shared address collectives using counter mechanisms
Blocksome, Michael; Dozsa, Gabor; Gooding, Thomas M; Heidelberger, Philip; Kumar, Sameer; Mamidala, Amith R; Miller, Douglas
2014-02-18
A shared address space on a compute node stores data received from a network and data to transmit to the network. The shared address space includes an application buffer that can be directly operated upon by a plurality of processes, for instance, running on different cores on the compute node. A shared counter is used for one or more of signaling arrival of the data across the plurality of processes running on the compute node, signaling completion of an operation performed by one or more of the plurality of processes, obtaining reservation slots by one or more of the plurality of processes, or combinations thereof.
International Nuclear Information System (INIS)
1989-01-01
The dissociation constants of the weak acids derived from quinizarin (1,4-dihydroxy anthraquinone); QMF (2-(2-fury l methyl)), QMPH (2-(2-phenyl methyl)) and QMN (2-(2-naphthyl methyl)) quinizarin were determined. The stability constants of uranyl complexes with the above mentioned ligands were investigated by: 1. The molar-ratio method. 2. Computer program
JTM advances in uncharted territories: diseases and disorders of unknown etiology
Panelli, Monica C.
2017-01-01
We are delighted to announce a new section in the Journal of Translational Medicine, ?Illnesses of Unknown Etiology?. This section aims to provide a translational medicine forum for the publication of research on illnesses, multisystem diseases and syndromes of unknown etiology. Examples of these include Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Fibromyalgia Syndrome.
DEFF Research Database (Denmark)
Mathew, Joseph L; El Dib, Regina; Mathew, Preethy J
2008-01-01
The benefits and harms of hepatitis B vaccination in persons not previously exposed to hepatitis B infection or with unknown exposure status have not been established.......The benefits and harms of hepatitis B vaccination in persons not previously exposed to hepatitis B infection or with unknown exposure status have not been established....
Road Map to Address Cognitive Health
Centers for Disease Control (CDC) Podcasts
2014-06-09
In this podcast, CDCâs Dr. Lynda Anderson highlights the important roles that states and communities can play in addressing cognitive health as part of overall health. Created: 6/9/2014 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP). Date Released: 6/9/2014.
Addressing production stops in the food industry
DEFF Research Database (Denmark)
Hansen, Zaza Nadja Lee; Herbert, Luke Thomas; Jacobsen, Peter
2014-01-01
This paper investigates the challenges in the food industry which causes the production lines to stop, illustrated by a case study of an SME size company in the baked goods sector in Denmark. The paper proposes key elements this sector needs to be aware of to effectively address production stops......, and gives examples of the unique challenges faced by the SME food industry....
Innovations for Addressing the Canker of Corruption
African Journals Online (AJOL)
There is a global consensus that addressing corruption and building good governance are pre-requisites for developing people, markets and the environment. Many researches on corruption and institutions measuring corruption perceptions have rated many African countries as being corrupt and suggestions for ...
Address tracing of parallel systems via TRAPEDS
Stunkel, Craig B.; Janssens, Bob; Fuchs, W. K.
1992-01-01
Trace-driven simulation is an important aid in performance analysis of computer systems. Capturing address traces to use in these simulations, however, is a difficult problem for parallel processor architectures. A technique termed TRAPEDS modifies executable code (at the assembly language level) to dynamically collect the address trace from executing code. TRAPEDS has recently been implemented on both a hypercube multicomputer and a shared-memory multiprocessor. Particular attention is focused on strategies for efficiently and accurately collecting traces from both classes of parallel machines. The iPSC/2 hypercube multicomputer implementation traces both user and system code, and performs simulation on-the-fly to avoid large storage costs. Strategies are detailed for mitigating address trace distortion when collecting operating system traces. The Encore Multimax multiprocessor implementation uses a timer-based approach to reflect the interleaving of the processor traces and stores the traces to disc. Time and space overhead results are presented for both TRAPEDS implementations. Experimental cache simulation results derived from iPSC/2 address traces are presented to illustrate the importance of tracing operating system references.
Addressing Measurement Issues Related to Bullying Involvement
Casper, Deborah M.; Meter, Diana J.; Card, Noel A.
2015-01-01
In this article, we address measurement issues related to select aspects of bullying involvement with the goal of moving psychometrically sound measurement practices toward applied bullying research. We first provide a nontechnical introduction to psychometric considerations in measuring bullying involvement, highlighting the importance of…
Addressing Youth Employment Through Micro- and Small ...
International Development Research Centre (IDRC) Digital Library (Canada)
... -provide empirical evidence to inform the design of Ethiopia's second Growth and Transformation Plan, specifically as it relates to addressing youth unemployment. The Association of Ethiopian Microfinance Institutions will manage the project, bringing together a multidisciplinary group of experts from various institutions.
Addressing the Global Burden of Breast Cancer
The US National Cancer Institute’s Center for Global Health (CGH) has been a key partner in a multi-institutional expert team that has developed a set of publications to address foundational concerns in breast cancer care across the cancer care continuum and within limited resource settings.
Addressing African feminism | Chidammodzi | Journal of Humanities
African Journals Online (AJOL)
Journal of Humanities. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 8-9, No 1 (1995) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Addressing African feminism. HF Chidammodzi. Abstract.
37 CFR 301.2 - Official addresses.
2010-07-01
... courier (excluding Federal Express, United Parcel Service and similar courier services), the envelope must... of overnight delivery services such as Federal Express, United Parcel Service, etc., due to delays in... overnight delivery using United States Postal Service Express Mail), the envelope should be addressed to...
THE ROLE OF NUTRITIONAL INFORMATION IN ADDRESSING ...
African Journals Online (AJOL)
The paper discusses the role of nutritional information for addressing under-five child malnutrition in Tanzania. The paper is based on a master's dissertation whose objective was to determine the sources of nutritional information used to provide nutritional information to mothers in Maternal and Child Health (MCH) clinics, ...
Parallel Memory Addressing Using Coincident Optical Pulses
1989-09-15
defined for Al and M, respectively, and at each does not have to be the same for every pair of adjacent destination nodeje D, u D2, the number of...system, a register SKIP may be used at each nodej has to skip before reading the messages addressed node to indicate the number of messages to be
Volume 1: president's address, CNA committee reports
International Nuclear Information System (INIS)
The president's address summarizes the 1974-75 activities of the CNA and reports are given by CNA subcommittees on codes, standards and practices, economic development, education and manpower, international affairs, nuclear insurance, nuclear safety and environment, public relations, and technology. (E.C.B.)
Addressing Youth Employment Through Micro- and Small ...
International Development Research Centre (IDRC) Digital Library (Canada)
Addressing Youth Employment Through Micro- and Small-Enterprise Development in Ethiopia ... This project aims to provide solid evidence on whether the Ethiopian government's efforts are helping youth, who is benefiting and who is not, and how policies ... GrowInclusive : la plateforme tant attendue est en construction.
Promoting inclusive approaches to address urbanisation challenges ...
African Journals Online (AJOL)
Promoting inclusive approaches to address urbanisation challenges in Kigali. ... Kigali has embarked on a rapid urbanisation and modernisation process. ... housing for the majority of urban residents remains a challenge which continues to impact on both the population's living conditions and sustainable urban planning.
Addressing the market research skills gap
Nunan, Daniel
2015-01-01
This Viewpoint focuses on the debate in market research around the gap between academia and practitioners. It argues that the debate misses the key role that universities play in the provision of market research skills and that it is this skills gap that needs to be addressed in order to ensure the future of research as a profession.
How Sociology Texts Address Gun Control
Tonso, William R.
2004-01-01
William R. Tonso has chosen an issue that he knows something about to examine how sociology textbooks address controversy. Appealing for gun control is fashionable, but it is at odds with a fondness that ordinary Americans have for their firearms--one that is supported by a growing body of research on deterrence to crime. There are two sides to…