835 research outputs found
R&D Offshoring in Multinational Enterprises: Relevance of Transaction Cost and Internationalization Theories
Purpose âThe purpose of this paper is to examine recent trends in R&D offshoring by US multinational enterprises (MNEs) against a wellâestablished conceptual framework derived from transaction cost and internalization theories, as well as challenges to it. Design/methodology/approach âThe paper develops and tests a parsimonious model of crossâcountry variation in R&D performed by affiliates of MNEs based on a 31âcountry, 15âyear dataset of US nonâbank majorityâowned foreign affiliates (MOFAs). Findings âConsistent with the implications of transaction cost and internalization frameworks, the findings show that the location of R&D offshoring is significantly determined by ownership of physical assets by MNEs in the host country and host country technological capability. Practical implications âR&D offshoring can enhance the quality and the quantity of knowledge flows between home country and host country R&D centers. The resulting positive knowledge spillâover effects can increase the welfare and productivity of an MNE and its home country in the long run. Originality/value âThe paper provides a comprehensive explanation for MNEs\u27 R&D offshoring based on transaction costs, internalization framework and technological factors
Policies and User Perception based Data Security in the Cloud
In todayâs world, most of the companies migrated from desktop devices to the cloud. Cloud is a platform for storing large amount of data. Among this it is very necessary to provide data security over the un-trusted cloud. We cannot trust the cloud provider when sensitive data is stored in the cloud so that, various security aspects are required to protect sensitive data which is stored on the cloud. The main problem is that, how to deal with such security issues to protect sensitive data. With the help of policy based security, it is possible to minimize data security issues and to improve data privacy. This paper proposes a user perception framework. According to this framework, owner of the organization is able to tell which user of that organization will follow which rights. A particular user should provide his/her privileges to the owner and he will protect userâs data by giving full rights to access data based on the identification of the users
Online multiple hypothesis testing for reproducible research
Modern data analysis frequently involves large-scale hypothesis testing,
which naturally gives rise to the problem of maintaining control of a suitable
type I error rate, such as the false discovery rate (FDR). In many biomedical
and technological applications, an additional complexity is that hypotheses are
tested in an online manner, one-by-one over time. However, traditional
procedures that control the FDR, such as the Benjamini-Hochberg procedure,
assume that all p-values are available to be tested at a single time point. To
address these challenges, a new field of methodology has developed over the
past 15 years showing how to control error rates for online multiple hypothesis
testing. In this framework, hypotheses arrive in a stream, and at each time
point the analyst decides whether to reject the current hypothesis based both
on the evidence against it, and on the previous rejection decisions. In this
paper, we present a comprehensive exposition of the literature on online error
rate control, with a review of key theory as well as a focus on applied
examples. We also provide simulation results comparing different online testing
algorithms and an up-to-date overview of the many methodological extensions
that have been proposed.Comment: Updated in response to reviewer comment
A composite generalization of Villeâs martingale theorem using e-processes
We provide a composite version of Villeâs theorem that an event has zero measure if and only if there exists a nonnegative martingale which explodes to infinity when that event occurs. This is a classic result connecting measure-theoretic probability to the sequence-by-sequence game-theoretic probability, recently developed by Shafer and Vovk. Our extension of Villeâs result involves appropriate composite generalizations of nonnegative martingales and measure-zero events: these are respectively provided by âe-processesâ, and a new inverse capital outer measure. We then develop a novel line-crossing inequality for sums of random variables which are only required to have a finite first moment, which we use to prove a composite version of the strong law of large numbers (SLLN). This allows us to show that violation of the SLLN is an event of outer measure zero and that our e-process explodes to infinity on every such violating sequence, while this is provably not achievable with a nonnegative (super)martingale
Development, Validation, and Potential Enhancements to the Second-Generation Operational Aerosol Product at the National Environmental Satellite, Data, and Information Service of the National Oceanic and Atmospheric Administration
A revised (phase 2) single-channel algorithm for aerosol optical thickness, tau(sup A)(sub SAT), retrieval over oceans from radiances in channel 1 (0.63 microns) of the Advanced Very High Resolution Radiometer (AVHRR) has been implemented at the National Oceanic and Atmospheric Administration's National Environmental Satellite Data and Information Service for the NOAA 14 satellite launched December 30, 1994. It is based on careful validation of its operational predecessor (phase 1 algorithm), implemented for NOAA 14 in 1989. Both algorithms scale the upward satellite radiances in cloud-free conditions to aerosol optical thickness using an updated radiative transfer model of the ocean and atmosphere. Application of the phase 2 algorithm to three matchup Sun-photometer and satellite data sets, one with NOAA 9 in 1988 and two with NOAA 11 in 1989 and 1991, respectively, show systematic error is less than 10%, with a random error of sigma(sub tau) approx. equal 0.04. First results of tau(sup A)(sub SAT) retrievals from NOAA 14 using the phase 2 algorithm, and from checking its internal consistency, are presented. The potential two-channel (phase 3) algorithm for the retrieval of an aerosol size parameter, such as the Junge size distribution exponent, by adding either channel 2 (0.83 microns) from the current AVHRR instrument, or a 1.6-microns channel to be available on the Tropical Rainfall Measurement Mission and the NOAA-KLM satellites by 1997 is under investigation. The possibility of using this additional information in the retrieval of a more accurate estimate of aerosol optical thickness is being explored
Study of sickle cell anaemia with clinical and hematological correlation
Background: Sickle cell anaemia is a hemoglobinopathy with the production of abnormal hemoglobin, HbS which when exposed to hypoxemia produces sickling of RBC. Severity of the disease depends on the percentage of HbS. Rise in the levels of Hb F is associated with less intense clinical course. Drugs targeted at increasing levels of HbF have prognostic significance. The aim of the study is to analyse the age, sex distribution, clinical, hematological and electrophoretic appearances and to compare with other studies.Methods: 300 sickle cell positive patients, both male and females who attended OPD were studied with all the clinical findings and hematological parameters. 52 cases were subjected to electrophoresis.Results: Males were 154 and females were 146. Degree of anaemia was severe in females when compared to males. Of 52 cases subjected for electrophoresis 36 were homozygous, 15 were heterozygous and 1 case Sickle thalassemia. 7 cases showed HbF above 5%.Conclusions: Most of the patients were under 40 yrs suggesting decreased survival after that age. An increased level of HbF was associated with better prognosis suggesting the need to target at drugs which increase HbF
Isotopic-mass dependence of the A, B, and C excitonic band gaps in ZnO at low temperatures
Low temperature wavelength-modulated reflectivity measurements of isotopically engineered ZnO samples have yielded the dependence of their A, B, and C excitonic band gaps on the isotopic masses of Zn and O. The observed dependence is analyzed in terms of the band gap renormalization by zero-point vibrations via electron-phonon interaction and the volume dependence on isotopic mass. A simplified, two-oscillator model, employed in the analysis, yields zero-point renormalizations of the band gaps, -154 +/- 14 meV (A), -145 +/- 12 meV (B), and -169 +/- 14 meV (C), for ZnO with natural isotopic composition
Hemophilic patient for emergency spinal decompression
Hemophilia is mostly an inherited genetic disorder, caused by mutations in the clotting factor gene. With the available treatment options, life expectancy of a hemophilic patient is usually of that of the general population. Hence, it is not uncommon that they present for surgical procedures. However, hemophilic patients for the major surgical procedure are always a real challenge for the perioperative physician. We have recently encountered one such patient who was hospitalized with acute paraplegia due to a mass lesion of spine and successfully managed with the recovery of motor power. His pre-operative Factor VIII level was 0. Desmopressin nasal spray has a limited role in severe hemophilic. Our main concern was effective replacement therapy and maintenance of desired Factor VIII levels not only during surgery but also in the immediate post-operative period
Direct observation of LO phonon-plasmon coupled modes in the infrared transmission spectra of n-GaAs and n-InxGa1-xAs epilayers
The infrared transmission spectrum of Si-doped molecular beam epitaxy (MBE)-grown GaAs epilayers, 2-2.5-mum thick, measured in the oblique (Berreman) geometry, revealed distinct minima in p polarization. Given epilayer thickness \u3c reststrahlen wavelength, the minima are identified as the zone-center transverse optic phonon (omega(TO)) and the high-frequency LO phonon-plasmon coupled mode (omega(+)). Analysis of the experimental data yielded free-carrier concentrations ranging from 2.5x10(17) to 1.4x10(18) cm(-3). The same technique with MBE-grown Si-doped In0.53Ga0.47As epilayers (0.5-1 mum thick) yielded omega(+) modes corresponding to free-carrier concentrations of 8.2x10(16)-2.7x10(19) cm(-3). The observations of the transmission minima in the Berreman geometry and their interpretation demonstrate a direct and simple method for deducing free-carrier concentrations over a wide range
- âŠ