24,567 research outputs found
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
GO Barometer: meer wantrouwen en onvoldoende capaciteit binnen het vakgebied
No full textDe tweede editie van de GO Barometer is uit! De Stichting Kennis Gebiedsontwikkeling (SKG) brengt ook dit jaar de stand van zaken binnen het vakgebied van gebiedsontwikkeling in kaart. Gebiedsontwikkeling is een zaak van lange adem, dus er zijn veel overeenkomsten met 2022 – maar toch ook enkele opvallende verschillen. Vooral het stijgende onderlinge wantrouwen tussen partijen is opvallend. Daarnaast zet onvoldoende personele capaciteit de uitvoering van uitdagende ruimtelijke projecten verder onder druk.Urban Development ManagementPractice Chair Urban Area Developmen
Before I Let Go
No full textFront Cover -- Title Page -- Copyright -- Day One -- Midnight Flight -- A Land of Gold and Loneliness -- Stars and Stories -- Unpredictable -- Strangers, Traitors, Ghosts -- Framed Moments -- Loss -- Saints and Sourdough -- Doorways -- The Lonely Lake -- Memories of Infinity -- In the Company of Others -- Foreseen and Foretold -- Whispers in the Night -- Day Two -- Astronomical Twilight -- We Can Be Heroes -- Conversations -- The Choices We Make -- A New Lost -- Happily Sometimes -- Now Here's to You -- Planting Seeds -- To Those We Have Loved and Lost -- Pathways -- Abandon Hope -- Gifts -- Day Three -- Wholesome Lives and Hot Springs -- Birds with Broken Wings -- A Shrine of Blossoms -- Keeper of the Spa -- Writing on the Wall -- Nightmares -- The Way the World Changes -- Do You Understand Now? -- Fear Her -- Of the Dead, Nothing but Good -- No Need to Say Goodbye -- Scorn and Celebration -- Service, Interrupted -- Darkness Falls -- A Backback Full of Home -- The Smell of Smoke -- The Taste of Ashes -- Day Four -- Where Do We Go From Here? -- Polar Twilight -- Night Swimming -- Testimony -- A Cure for All Ills -- Fear about Town -- Empty Rooms, Lost Words -- Dear Diary -- History -- Allies -- Unexpected Friendship -- Northern Lights -- Day Five -- The Smell of Changing Weather -- Understanding Dawns -- Top of the Morning -- The Art of Living -- Stealing In -- The Art of Dying -- The Mist, the Woods, the Darkness -- Kyra vs. the Rest of the World -- Belonging -- Brushstrokes -- Let Me Tell You a Story -- Stolen Time -- The Way the World Ends -- Endless Night -- Endless Day -- Come to Steal Your Soul Away -- Saving the World -- Day Six -- Hero Days -- Homeward Bound -- All the Lives We Shared -- Author's Note -- Acknowledgments -- A Conversation with the Author -- About the Author -- Back CoverDescription based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
GO Barometer ’22: Integrale gebiedsontwikkeling vereist meer capaciteit en innovatie
No full textMet de eerste editie van de GO Barometer bracht de SKG dit voorjaar in kaart wat de stand van zaken is in het vakgebied van gebiedsontwikkeling. In dit artikel bespreken we de vijf belangrijkste inzichten uit de barometer en de discussie daarover tijdens het SKG Jaarcongres eind maart.Urban Development ManagementPractice Chair Urban Area Developmen
Design of pharmaceutical tablet formulation for a low water soluble drug : search for the critical concentration of starch based disintegrant applying percolation theory and F-CAD (Formulation-Computer Aided Design)
No full textThe topic of this PhD work is to search the critical concentration of starch based disintegrant applying percolation theory and F-CAD (Formulation-Computer Aided Design) in order to design a pharmaceutical tablet formulation for a low water soluble drug. Critical concentration of maize starch (MS) for a ternary mefenamic acid (MA) tablet formulation with respect to a minimum disintegration time is investigated. Additionally implemented application of F-CAD to compute the disintegration time of MA tablet formulation is presented. This topic is related to push forward the idea of Quality by Design (QbD) of FDA (Food and Drug Administration) / EMEA (European Medicines Agency) / PMDA (Pharmaceuticals and Medical Devices Agency) and the exploration of the design space according to ICH (International Conference of Harmonization) Q8.
The results of this work shows that the application of percolation theory is not limited to binary tablet formulation. The critical concentration of MS described by the renormalized MS concentration, MS/(MS+MA) applying the renormalization technique is always equal 0.198 (dimensionless). Moreover the critical concentration of MS is optimized using the spline approximation with the dataNESIA software. It is leading to a minimum disintegration time at 0.206, dimensionless, renormalized, which is very close to the experimental value of 0.198. According to the percolation theory, a minimum disintegration time corresponds to the formation of a continuous water-conducting cluster through the entire tablet. The critical volume fraction of an ‘infinite cluster’ that water can diffuse through the entire MA tablets are calculated with taking into account for the geometrical considerations between MS and MA particles based on random close packed (RCP) spheres system. The critical volume fraction of MS is calculated by the multiplication of critical concentration of MS and the solid fraction of MA tablets; which is within the range of 0.16 ± 0.01 (v/v). It is concluded that the critical volume fraction for three dimensional lattices is equal to 0.16 ± 0.01 (v/v); which is useful for the calculation of the critical concentration of starch based disintegrant in order to design the pharmaceutical tablet formulation based on scientific approach proposed by ICH Q8 guidance.
In addition, the disintegration behavior in the neighborhood of the percolation threshold is explained mathematically by the basic equation of the percolation theory, yielding a critical exponent q equal to 0.28 ± 0.06 (Quality of fit: r2 = 0.84). This value is close to the critical exponent for three dimensional lattices (q = 0.4). Thus, it is important, within a planned experimental design to optimize the disintegrant to take into account the percolation theory. However it has to be kept in mind that the determination of the percolation threshold and critical exponent does not give an answer about the absolute value of the disintegration time. Dissolution Simulation (DS) module, which is the one of F-CAD based on cellular automata algorithm is used to simulate the disintegration time of a MA tablet. Disintegration time of tablet is assumed as the time elapsed till the water is detected at the geometric center of the virtual tablet. Comparison of experimental disintegration time of MA tablet and computed specific time point for water to reach the geometric center of the tablet by using F-CAD software has been carried out and shown an acceptable correlation (Correlation coefficient: r = 0.81). The detailed evaluation of the data shows that there is still a need for optimization of F-CAD for the calculation of the disintegration time in order to achieve a similar or the same performance like in the prediction of the dissolution profile of a tablet formulation. It is concluded that F-CAD software is the only software so far, which is capable of computing the disintegration time of tablets. The software has a great potential to be improved and to be not only used for the safe prediction of the dissolution profile of a tablet formulation but also for a safe prediction of the disintegration time. Thus, such a software is one of the tools for the substitution of laboratory experiments for the purpose of the design and development of new pharmaceutical solid dosage forms. The replacement of expensive laboratory experiments by in-silico experiments is an important issue to reduce development costs and to comply with the requirements of ICH Q8 exploring the design space with response surface methodology. The results of this thesis show in addition that the application of percolation theory is a must in order to detect percolation thresholds. It is important to know the response surfaces close to the percolation threshold of sensitive tablet properties such as the disintegration time to get information about the robustness of the selected formulation. In this context one has to put the question forward if the application of percolation theory should be an integral part of the guidelines of ICH Q8 exploring the formulation design space
Terahertz Pioneer: Hiromasa Ito
No full textHiromasa Ito grew up wanting to be a scientist like
his father before him. The fifth of six children, he was
raised in the aftermath of World War II, and like others who
have been the subject of these articles, the impact of the war
on Ito's life was more than an historic footnote. Ito's father,
Yoji Ito was a prominent member of the Japanese Navy (a
Commander) and was extremely active in the development of
Japan's first radar instrumentation in the early 1940's. Educated
at the Technische Hochschule Dresden, Germany, under Heinrich
Barkhausen, Yoji worked on high power magnetrons, including
the infamous Ku-Go (a microwave variation of Tesla's
invisible death ray concept [1]). After the war he was severely
restricted in his employment, but he managed to start a company,
Koden Electronics, for the peacetime use of his Naval
radio technology. Koden Electronics, Tokyo, Japan, still exists
today and is known for marine navigation and fish finders
Electrochemical detection of nitrite on poly(pyronin Y)/graphene nanocomposites modified ITO substrate
No full textThe present study reports on an easy preparation of poly(pyronin Y)/graphene (poly(PyY)/graphene) nanocomposites thin films on indium tin oxide coated glass substrates (ITO). The thin films of poly(PyY)/graphene nanocomposites are prepared by a novel method consisting of three steps; (i) preparation of graphene oxide (GO) thin films on ITO by spin-coating method, (ii) self-assembly of PyY molecules from aqueous solution onto the GO thin film, (iii) surface-confined electropolymerization (SCEP) of the adsorbed PyY molecules on the GO thin film. The as-prepared poly(PyY)/graphene nanocomposites thin films are characterized by using electroanalytical and spectroscopic techniques. Afterwards, the graphene-based polymeric dye thin film on ITO is used as an electrode in an electrochemical cell. Its performance is tested for electrochemical detection of nitrite. Under optimized conditions, the electrocatalytical effect of the nanocomposites thin film through electrochemical oxidation of nitrite is better than that of GO coated ITO. (C) 2016 Elsevier Ltd. All rights reserved
Distributive concerns when replacing a pay-as-you-go system with a fully funded system
No full textThe author uses a simulation model to quantify the impact on income distribution of having a neutral social security program that is fully funded replace a progressive social security program that redistributes income toward the poor but is financed by a pay-as-you-go method. He finds that if the original pay-as-you-go system is large enough to yield an income replacement rate of at least 40 percent for the middle class and 200 percent for the poor, then the proposed change helps the poor in the long run, so long as public debt does not increase by more than 40 percent of GDP during the transition. Such a reform allows an increase in the capital stock per worker, so in the long run the poor benefit more through higher real wages than they lose because progressive redistribution has ended. In the short run, however, a compensatory program is needed because the poor lose their subsidy before receiving the long-term benefit. In most cases, the 40 percent of GDP available from the increase in public debt is enough to finance a transfer program that compensates the poor in the"short"run (the first 50 years). The author concludes that concern about the welfare of the poor is unwarranted, in both the short and long runs, if the compensatory program is implemented.Environmental Economics&Policies,Economic Theory&Research,Safety Nets and Transfers,Services&Transfers to Poor,Rural Poverty Reduction
Low voltage & controlled switching of MoS2-GO resistive layers based ReRAM for non-volatile memory applications
No full textEmerging information technology and data deluge foster the unprecedented demands of higher chip density, clocking speed, data storage and lower power dissipation for on-chip non-volatile memories (NVMs). Here, two types of metal-insulator-metal (MIM) based NVM structures were fabricated and demonstrated involving controlled functionalization of molybdenum disulfide (MoS2) and graphene oxide (GO) nanocomposite as a resistive switching layer. The first type of device constitutes Aluminum (Al) top and bottom electrode resulting in the Al/MoS2-GO/Al structure. While the second type of device uses Al top electrode and Indium Tin Oxide (ITO) bottom electrode resulting in Al/MoS2-GO/ITO. The current-voltage (I-V) characteristics for fabricated Al/MoS2-GO/Al and Al/MoS2-GO/ITO MIM structures exhibited considerable I-ON/I-OFF ratio of similar to 10(2) (SET and RESET state at 0.5 V and -0.4 V) and similar to 10(1) (SET and RESET state at 0.3 V and -1V), respectively. The I-V characteristics for Al/MoS2-GO/Al MIM structure showed low voltage switching, substantial memory retention similar to 10(4) s and endurance for up to 25 cycles. The low voltage and controlled switching operation for Al/MoS2-GO/Al MIM structures may be attributed to the presence of a large number of oxygen vacancies, defects in MoS2-GO, promoting enhanced charge hopping via interfacial oxide at MoS2-GO/Al interface as compared to MoS2-GO/ITO
Heterojunction photodetector based on graphene oxide sandwiched between ITO and p-Si
No full textThe drop casting method is utilized on indium tin oxide (ITO)-coated glass in order to prepare a sandwiched ITO/graphene oxide (ITO/GO) with silicon dioxide/p-type silicon (SiO2/p-Si) heterojunction photodetector. The partially sandwiched GO layer with SiO2/p-Si substrate exhibits dual characteristics as it showed good sensitivity towards the illumination of infrared (IR) laser at wavelength of 974 nm. Excellent photoconduction is also observed for current–voltage (I–V) characteristics at various laser powers. An external quantum efficiency greater than 1 for a direct current bias voltage of 0 and 3 V reveals significant photoresponsivity of the photodetector at various laser frequency modulation at 1, 5 and 9 Hz. The rise times are found to be 75, 72 and 70 μs for 1, 5 and 9 Hz while high fall times 455, 448 and 426 are measured for the respective frequency modulation. The fabricated ITO/GO-SiO2/p-Si sandwiched heterojunction photodetector can be considered as a good candidate for applications in the IR regions that do not require a high-speed response
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