961 research outputs found
Student Expectations in the New Millennium
No full textHigher education has experienced vast changes as a result of global political and economic developments. Cultural and social changes in the last decade have also added to the continuing evolution of higher education. These changes inevitably lead to changing expectations of students entering higher education. An adequate understanding of student expectations is crucial in ensuring a good fit between higher educational institutions and their students. This study attempts to carry out a baseline descriptive-quantitative research on student expectations in the higher education of Hong Kong. Four scales have been developed to measure students’ attitude toward: 1. job-oriented curriculum design, 2. user-friendly course delivery method, 3. opportunities for lifelong learning, and 4. student consumerism. Students’ priority of what makes a good university, their reasons for going to university, and their self-perception of ability to cope with university life are also explored. The Student Expectations Questionnaire (developed by the author) was used to gather data from 857 first-year undergrads from nine institutions of higher education in Hong Kong. Analyses include, among others, gender, age, major of study as well as institution comparisons
Guthion
Get PDFprepared by Syracuse Research Corporation ; prepared for U.S. Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry.Chemical manager(s)/author(s): Nickolette Roney, Selene Chou, Yee-Wan Stevens, ATSDR, Division of Toxicology and Environmental Medicine, Atlanta, GA; Antonio Quinones-Rivera, David Wohlers, Mario Citra, Syracuse Research Corporation, North Syracuse, NY. --p. ix."This toxicological profile is prepared in accordance with guidelines developed by the Agency for Toxic Substances and Disease Registry (ATSDR) and the Environmental Protection Agency (EPA). The original guidelines were published in the Federal Register on April 17, 1987"--p. v.Includes bibliographical references (p. 159-176) and index.20081122
Classification of solutions to the isotropic horospherical -Minkowski problem in hyperbolic plane
Get PDFIn \cite{LX}, the first author and Xu introduced and studied the
horospherical -Minkowski problem in hyperbolic space . In
particular, they established the uniqueness result for solutions to this
problem when the prescribed function is constant and . This paper
focuses on the isotropic horospherical -Minkowski problem in hyperbolic
plane , which corresponds to the equation
\begin{equation}\label{0}
\varphi^{-p}\left(\varphi_{\theta\theta}-\frac{\varphi_{\theta}^2}{2\varphi}+\frac{\varphi-\varphi^{-1}}{2}\right)=\gamma\quad\text{on}\
\mathbb{S}^1, \end{equation} where is a positive constant. We provide
a classification of solutions to the above equation for , as well as a
nonuniqueness result of solutions for . Furthermore, we extend this
problem to the isotropic horospherical -weighted -Minkowski problem in
hyperbolic plane and derive some uniqueness and nonuniqueness results.Comment: 19 pages, 2 figures. All comments are welcom
Proposed shunt rounding technique for large-scale security constrained loss minimization
No full textThe official published version can be obtained from the link below - Copyright @ 2010 IEEE.Optimal reactive power flow applications often model large numbers of discrete shunt devices as continuous variables, which are rounded to their nearest discrete value at the final iteration. This can degrade optimality. This paper presents novel methods based on probabilistic and adaptive threshold approaches that can extend existing security constrained optimal reactive power flow methods to effectively solve large-scale network problems involving discrete shunt devices. Loss reduction solutions from the proposed techniques were compared to solutions from the mixed integer nonlinear mathematical programming algorithm (MINLP) using modified IEEE standard networks up to 118 buses. The proposed techniques were also applied to practical large-scale network models of Great Britain. The results show that the proposed techniques can achieve improved loss minimization solutions when compared to the standard rounding method.This work was supported in part by the National Grid and in part by the EPSRC. Paper no. TPWRS-00653-2009
Physical origin of Davydov splitting and resonant Raman spectroscopy of Davydov components in multilayer MoTe2
No full textWe systematically study the high-resolution and polarized Raman spectra of multilayer (ML) MoTe2. The layer-breathing (LB) and shear (C) modes are observed in the ultralow-frequency region, which are used to quantitatively evaluate the interlayer coupling in ML MoTe2 based on the linear chain model, in which only the nearest interlayer coupling is considered. The Raman spectra on three different substrates verify the negligible substrate effect on the phonon frequencies of ML MoTe2. Ten excitation energies are used to measure the high-frequency modes of N-layer MoTe2 (NL MoTe2; N is an integer). Under the resonant excitation condition, we observe N-dependent Davydov components in ML MoTe2, originating from the Raman-active A(1)' (A(1g)(2)) modes at similar to 172 cm(-1). More than two Davydov components are observed in NL MoTe2 for N > 4 by Raman spectroscopy. The N-dependent Davydov components are further investigated based on the symmetry analysis. A van der Waals model only considering the nearest interlayer coupling has been proposed to well understand the Davydov splitting of high-frequency A(1)' (A(1g)(2)) modes. The different resonant profiles for the two Davydov components in 3L MoTe2 indicate that proper excitation energy of similar to 1.8 - 2.2 eV must be chosen to observe the Davydov splitting in ML MoTe2. Our work presents a simple way to identify layer number of ultrathin MoTe2 flakes by the corresponding number and peak position of Davydov components. Our work also provides a direct evidence from Raman spectroscopy of how the nearest van der Waals interactions significantly affect the frequency of the high-frequency intralayer phonon modes in multilayer MoTe2 and expands the understanding on the lattice vibrations and interlayer coupling of transition metal dichalcogenides and other two-dimensional materials.National Basic Research Program of China [2013CB921901, 2012CB932703]; National Natural Science Foundation of China [11225421, 11434010, 11474277, 61125402, 51172004, 11474007]SCI(E)[email protected]; [email protected]
Assessing scientific research performance and impact with single indices
Get PDFWe provide a comprehensive and critical review of the h-index and its most important modifications proposed in the literature, as well as of other similar indicators measuring research output and impact. Extensions of some of these indices are presented and illustrated.Citation metrics, Research output, h-index, Hirsch index, h-type indices
Characteristics and Trends of C-H Activation Research: A Review of Literature
No full text
Background: C-H activation has attracted great interests over the past two decades, which resulted
in an explosive growth in both quality and quantity of published papers related to this topic.
Objective: In this review, a bibliometric analysis was performed to evaluate the publications in this field from
1996 to 2015 based on the Science Citation Index (SCI) Expanded database. This work presented a detailed
overview of C-H activation from aspects of types of articles, citations, h-indices, languages, years, journals,
institutions, countries and author keywords.
Conclusion: The results showed that the USA took the leading position in this research field, followed by P. R.
China and German. Chinese Academy of Science had the most publications and the highest h-index, Scripps
Research Institute won the first place as far as the highest average citation per paper is concerned. Organometallics,
Angewandte Chemie International Edition and Journal of the American Chemical Society were the most
productive journals in this field, and Chemistry was the most frequently used subject category. Keywords
analysis indicated that most research focused on the Palladium, Rhodium and Copper catalyzed cross-coupling
synthetic method development for the heterocycle synthesis. The research about exploring the asymmetric C-H
functionalization, mechanism investigation and solving the regioselectivity issue is the development trend in
this area.
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New Era of Air Quality Monitoring from Space: Geostationary Environment Monitoring Spectrometer (GEMS)
No full textAuthors:- Jhoon Kim, Ukkyo Jeong, Myoung-Hwan Ahn, Jae H. Kim, Rokjin J. Park, Hanlim Lee, Chul Han Song, Yong-Sang Choi, Kwon-Ho Lee, Jung-Moon Yoo, Myeong-Jae Jeong, Seon Ki Park, Kwang-Mog Lee, Chang-Keun Song, Sang-Woo Kim, Young Joon Kim, Si-Wan Kim, Mijin Kim, Sujung Go, Xiong Liu, Kelly Chance, Christopher Chan Miller, Jay Al-Saadi, Ben Veihelmann, Pawan K. Bhartia, Omar Torres, Gonzalo González Abad, David P. Haffner, Dai Ho Ko, Seung Hoon Lee, Jung-Hun Woo, Heesung Chong, Sang Seo Park, Dennis Nicks, Won Jun Choi, Kyung-Jung Moon, Ara Cho, Jongmin Yoon, Sang-kyun Kim, Hyunkee Hong, Kyunghwa Lee, Hana Lee, Seoyoung Lee, Myungje Choi, Pepijn Veefkind, Pieternel F. Levelt, David P. Edwards, Mina Kang, Mijin Eo, Juseon Bak, Kanghyun Baek, Hyeong-Ahn Kwon, Jiwon Yang, Junsung Park, Kyung Man Han, Bo-Ram Kim, Hee-Woo Shin, Haklim Choi, Ebony Lee, Jihyo Chong, Yesol Cha, Ja-Ho Koo, Hitoshi Irie, Sachiko Hayashida, Yasko Kasai, Yugo Kanaya, Cheng Liu, Jintai Lin, James H. Crawford, Gregory R. Carmichael, Michael J. Newchurch, Barry L. Lefer, Jay R. Herman, Robert J. Swap, Alexis K. H. Lau, Thomas P. Kurosu, Glen Jaross, Berit Ahlers, Marcel Dobber, C. Thomas McElroy, and Yunsoo ChoiThe Geostationary Environment Monitoring Spectrometer (GEMS) is scheduled for
launch in February 2020 to monitor air quality (AQ) at an unprecedented spatial and temporal
resolution from a geostationary Earth orbit (GEO) for the first time. With the development of
UV–visible spectrometers at sub-nm spectral resolution and sophisticated retrieval algorithms,
estimates of the column amounts of atmospheric pollutants (O₃
, NO₂
, SO₂
, HCHO, CHOCHO, and
aerosols) can be obtained. To date, all the UV–visible satellite missions monitoring air quality
have been in low Earth orbit (LEO), allowing one to two observations per day. With UV–visible
instruments on GEO platforms, the diurnal variations of these pollutants can now be determined.
Details of the GEMS mission are presented, including instrumentation, scientific algorithms, predicted performance, and applications for air quality forecasts through data assimilation. GEMS
will be on board the Geostationary Korea Multi-Purpose Satellite 2 (GEO-KOMPSAT-2) satellite
series, which also hosts the Advanced Meteorological Imager (AMI) and Geostationary Ocean
Color Imager 2 (GOCI-2). These three instruments will provide synergistic science products to
better understand air quality, meteorology, the long-range transport of air pollutants, emission
source distributions, and chemical processes. Faster sampling rates at higher spatial resolution
will increase the probability of finding cloud-free pixels, leading to more observations of aerosols
and trace gases than is possible from LEO. GEMS will be joined by NASA’s Tropospheric Emissions:
Monitoring of Pollution (TEMPO) and ESA’s Sentinel-4 to form a GEO AQ satellite constellation in
early 2020s, coordinated by the Committee on Earth Observation Satellites (CEOS).The GEMS program is supported by the National Institute of Environmental Research (NIER), the Ministry of Environment, South Korea. This project is supported by the Korea Ministry
of Environment (MOE) as Public Technology Program based on Environmental Policy (2017000160001).
Research at the Smithsonian Astrophysical Observatory was supported by a NASA USPI Grant “SAO
Participation in the Korean Geostationary Environment Monitoring Spectrometer (GEMS): Instrument Design and Algorithm Development.” Part of the research was carried out at the Jet Propulsion
Laboratory, California Institute of Technology, under a contract with the National Aeronautics and
Space Administration. Work done by HI was supported by the Environment Research and Technology
Development Fund (2-1901) of the Environmental Restoration and Conservation Agency of Japan, JSPS
KAKENHI (JP19H04235 and JP17K00529), the JAXA 2nd research announcement on the Earth Observations (19RT000351), and JST CREST (JPMJCR15K4).https://journals.ametsoc.org/view/journals/bams/101/1/bams-d-18-0013.1.xm
Confidence Regions for the Multinomial Parameter With Small Sample Size
Get PDFConsider the observation of n iid realizations of an experiment with d >= 2 possible outcomes, which corresponds to a single observation of a multinomial distribution M_d(n; p) where p is an unknown discrete distribution on \{1,...,d\}. In many applications, the construction of a confidence region for p when n is small is crucial. This
concrete challenging problem has a long history. It is well known that the confidence regions built from asymptotic statistics do not have good coverage when n is small.
On the other hand, most available methods providing non-asymptotic regions with controlled coverage are limited to the binomial case d = 2. In the present work, we
propose a new method valid for any d >= 2. This method provides condence regions with controlled coverage and small volume, and consists in the inversion of the "cover-
ing collection" associated to level-sets of the likelihood. The behavior when d=n tends to infinity remains an interesting open problem beyond the scope of this work
The safety and effectiveness of different methods of ear wax removal: a systematic review and economic evaluation
No full textEar wax (cerumen) is a natural secretion produced to protect the inner ear from dirt and other fragments by moving these particles towards the outer ear. If this process does not happen properly, wax may build up causing blockage in the ear canal and the possibility of impaction. People with a build up of ear wax may suffer from hearing loss, discomfort and, on occasions, infection. It may present problems in assessing hearing, blocking the view of the ear drum during medical examination and interfering with the fitting or function of hearing aids. Although it is thought to affect between 2% and 6% of the population in the England and Wales, some groups may be at a higher risk, such as those using hearing aids or with small ear canals and/or skin conditions. Recurrence is thought to be high among some of these groups. The consequences of the build up of ear wax in the ear canal are thought to be a common reason for consultation and cost in general practice with over 2 million consultations per year in the NHS.Methods of removal of ear wax include drops, flushing with water in general practice, and removal with suction or probes in specialist clinics. The relative safety and benefits of these different methods of removal remains uncertain. This research will systematically review published and unpublished evidence on the clinical and cost effectiveness of different methods for the removal of ear wax. Where appropriate, it will develop an economic model using data from this systematic review and other relevant sources to estimate the relative costs and benefits of different methods. In addition, the project will provide recommendations for future research to try to help answer any remaining areas of uncertainty
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