An application of adaptive cluster sampling for estimating total suspended sediment load.

Suspended sediment transport in river for a particular period is a timescale finite population. This population shows natural aggregation tendencies in sediment concentration particularly during floods. Adaptive cluster sampling (ACS) can be potentially conducted for sampling from this rare clustered population and estimating total load. To illustrate the performance of ACS in sediment estimation, a comparative study was carried out in the Gorgan-Rood River, Iran, with around a 5 year daily concentration record. The total sediment loads estimated by ACS were statistically compared to the observed load, estimations of selection at list time (SALT) and conventional sediment rating curve with and without correction factors. The results suggest that none of the sediment rating curves produced accurate estimates, while both ACS and SALT showed satisfactory results at a semi-weekly sampling frequency. The best estimation obtained by the rating curves did not show a percent error better than -40%; however, ACS and SALT underestimated the load at less than 5%. The results of this study suggest ACS could improve river monitoring programs

Effect of adaptive cluster sampling design on accuracy of sediment rating curve estimation.

Adaptive cluster sampling represents a design whereby more samples during high storm hydrographs can be obtained in the field compared to the commonly used calendar-based. To compare the effect of these sampling designs on accuracy of sediment rating curve estimation, we performed a study for Gorgan-Rood River, Iran by synthesizing sample sets from daily records. The load estimates obtained by conventional, two bias-corrected, and logged mean load within discharge classes (LMLWDCs) rating curves were statistically evaluated. All rating curves derived from calendar-based sample sets–except those with a nonparametric correction factor–underestimated the average load from 25 to 76%. Rating curves derived from adaptive sample sets, however, increased the sediment load to as much as 30%. Among this group of rating curves, LMLWDC produced the most accurate results with only 3% overestimation and a coefficient of variation in the order of 14% when the sampling frequency was semiweekly. The more accurate estimates from adaptive sample sets are likely due to the inclusion of more samples from high load periods

The use of a laser light-scattering technique in fluvial sediment measurement

In this paper, we report the measurement of sediment concentration using a laser light-scattering technique. In its present form, the technique suffers from several practical limitations but these are outweighed by the simplicity and speed of the technique. The procedures used in overcoming the accompanying problems are discussed

Knowledge management librarians: Evolving competencies in knowledge capture and dissemination in an academic environment

In this paper, we examine the roles and responsibilities of Knowledge Management (KM) librarians in a University and outline the skills and knowledge to illuminate and maximize the possibilities of the position, to provide new content in new mediums to an increasingly discerning user community. This relatively new position is being created as libraries strive to manage collaborative knowledge management technologies, upgrade the service model in reference, in particular enhancing the skills of ‘liaison officers’ when engaging with their patrons’ point-of-need preferences at their site, quality of knowledge, device choice, and their knowledge sharing and seeking behavior. We draw upon our own experiences in implementing a virtual knowledge sharing community in the International Islamic University Malaysia (IIUM) as well as referring to the latest literature on the topic. Our three-year implementation journey encompassing unforeseen problems and discussions in building workarounds, in how best to manage tacit knowledge amongst academic and non-academic staff, provided valuable insights, focusing in particular on KM training for all librarians, the development of an ‘unofficial’ knowledge management implementation curriculum (KMIC) and the formation of the IIUM KM Task Force to sustain KM initiatives in the academia. While many skills and experiences analyses have been conducted on other library positions, at the onset, the emerging KM librarian’s roles and responsibilities remained vague, leaving librarians interested in the position, unsure of what knowledge and skills to obtain. Hence, the need of a clear and robust KMIC policy framework was first seen to be crucial to sustain an effective KM implementation. Special emphasis was made in building the skills in intra-organisational cooperation and academic engagement for meeting the challenge of ‘capturing’ and codifying tacit knowledge and ultimately the successful cultivation of communities of practice in promoting a new form of ‘collective intelligence’ in the university

High temperature liquid chromatography of triazole fungicides on polybutadiene-coated zirconia stationary phase

High temperature liquid chromatography using water-rich and superheated water eluent is evaluated as a new approach for the separation of selected triazole fungicides, hexaconazole, tebuconazole, propiconazole, and difenoconazole. Using a polybutadiene-coated zirconia column at temperatures of 100–150 oC, clear separations were achieved when 100% purified water was utilized as organic-free eluent. Excellent limits of detection down to pg level were obtained for the separation of the triazole fungicides under optimum conditions. Van’t Hoff plots for the separations were linear suggesting that no changes occurred in the retention mechanism over the temperature range studied

T-odd Correlations in the Decay of Scalar Fermions

We define a CP sensitive asymmetry in the sfermion decays \ti f \to f \ti\chi^0_j \ell \bar \ell, f \ti\chi^0_j q \bar q, based on triple product correlations between the momenta of the outgoing fermions. We study this asymmetry in the MSSM with complex parameters. We show that the asymmetry is sensitive to the phases of the parameters $\mu$ and $M_1$. The leading contribution stems from the decay chain \ti f\to f \ti\chi^0_j\to f \ti\chi^0_1 Z\to f \ti\chi^0_1 \ell \bar \ell (f \ti\chi^0_1 q \bar q), for which we obtain analytic formulae for the amplitude squared. The asymmetry can go up to 3% for \ti f\to f \ti\chi^0_1 \ell \bar \ell, and up to 20% for \ti f\to f \ti\chi^0_1 q \bar q. We also estimate the rates necessary to measure the asymmetry.Comment: 18 pages, 5 figures, 2 tables; comments and references added; two tables added; version to appear in Eur. Phys.

Lower limit on the neutralino mass in the general MSSM

We discuss constraints on SUSY models with non-unified gaugino masses and R_P conservation. We derive a lower bound on the neutralino mass combining the direct limits from LEP, the indirect limits from gmuon, bsgamma, Bsmumu and the relic density constraint from WMAP. The lightest neutralino (mneutralino=6GeV) is found in models with a light pseudoscalar with MA<200GeV and a large value for $tan\beta$. Models with heavy pseudoscalars lead to mneutralino>18(29)GeV for $\tan\beta=50(10)$. We show that even a very conservative bound from the muon anomalous magnetic moment can increase the lower bound on the neutralino mass in models with mu<0 and/or large values of $\tan\beta$. We then examine the potential of the Tevatron and the direct detection experiments to probe the SUSY models with the lightest neutralinos allowed in the context of light pseudoscalars with high $\tan\beta$. We also examine the potential of an e+e- collider of 500GeV to produce SUSY particles in all models with neutralinos lighter than the W. In contrast to the mSUGRA models, observation of at least one sparticle is not always guaranteed.Comment: 37 pages, LateX, 16 figures, paper with higher resolution figures available at http://wwwlapp.in2p3.fr/~boudjema/papers/bound-lsp/bound-lsp.htm

A Compact Wideband Circularly Polarized Planar Monopole Antenna with Axial Ratio Bandwidth Entirely Encompassing the Antenna Bandwidth

The antenna presented in this study is a compact wideband monopole with wideband circular polarization that can be used across the whole antenna bandwidth. A rectangular C-shaped patch is partially covered by a ground plane in the proposed planar monopole antenna. Inserting a rectangular stub to the ground plane, etching a slit at the antenna patch, and adding a semicircular stub at the top of the antenna feed line increase the antenna impedance bandwidth (BW) and axial ratio bandwidth (ARBW). An FR4 substrate with overall dimensions of 25 mm×25 mm×1.6 mm is used to create the antenna. The antenna's observed impedance BW is 70% (4.55 GHz in the 4.3-8.85 GHz band), while the measured broadside ARBW is improved to a value of 82.2 percent (5.3 GHz along the range 3.8-9.1 GHz). The impedance BW is perfectly covered by the ARBW; hence the antenna can be considered circularly polarized throughout its operational spectrum. Within the antenna BW, the measured gain is greater than 1.5 dB

Single crystal of a one-dimensional metallo-covalent organic framework.

Although polymers have been studied for well over a century, there are few examples of covalently linked polymer crystals synthesised directly from solution. One-dimensional (1D) covalent polymers that are packed into a framework structure can be viewed as a 1D covalent organic framework (COF), but making a single crystal of this has been elusive. Herein, by combining labile metal coordination and dynamic covalent chemistry, we discover a strategy to synthesise single-crystal metallo-COFs under solvothermal conditions. The single-crystal structure is rigorously solved using single-crystal electron diffraction technique. The non-centrosymmetric metallo-COF allows second harmonic generation. Due to the presence of syntactic pendant amine groups along the polymer chains, the metallopolymer crystal can be further cross-linked into a crystalline woven network

Dual-Band MIMO Antenna Design for 5G Smartphones Mobile Communications

In this research, an innovative L-shape slot that is fed by F-shape dual-band six-Elements multiple-input multiple-output (MIMO) antenna for mobile phones that operate in a 5G spectrum is demonstrated. This proposed antenna has six antenna elements that can operate in dual band sub-6 GHz for 5G band spectrums at 3.42-3.77 GHz and at 5.30-5.63 GHz. Every antenna element has an L-shaped slot in the ground fed by the same feedline that support the matching of the F-shaped microstrip lines. Important features of the anticipated layout are examined. It provides excellent efficiency at the operation band, appropriate isolation, adequate radiation coverage, and good S-parameters. Ant 3's provided the maximum return loss at 3.6 GHz which is-35 dB, whereas Ant 5 and Ant 6 provide the highest return losses at 5.4 GHz which is-38dB of the suggested dual-band frequency of 5G smartphones. To validate the exactness of the constructed MIMO antenna performances, the sample prototyping and experimentally measured outcomes were carried out in the Lab. Both simulated and measure result assessments revealed an extremely excellent understanding of both results. satisfactory input impedance and mutual coupling characteristics. Future smartphones can leverage the proposed design for high data-rate cellular connectivity because of these appealing properties. This is an open-access article under the CC BY 4.0 license (http://creativecommons.org/licenses/by/4.0/) Publisher : Middle Technical Universit