353 research outputs found
The Peculiar Velocity Function of Galaxy Clusters
The peculiar velocity function of clusters of galaxies is determined using an
accurate sample of cluster velocities based on Tully-Fisher distances of Sc
galaxies (Giovanelli et al 1995b). In contrast with previous results based on
samples with considerably larger velocity uncertainties, the observed velocity
function does not exhibit a tail of high velocity clusters. The results
indicate a low probability of \,5\% of finding clusters with
one-dimensional velocities greater than 600 {\kms}. The root-mean-square
one-dimensional cluster velocity is 29328 {\kms}. The observed cluster
velocity function is compared with expectations from different cosmological
models. The absence of a high velocity tail in the observed function is most
consistent with a low mass-density (0.3) CDM model, and is
inconsistent at level with = 1.0 CDM and HDM models.
The root-mean-square one-dimensional cluster velocities in these models
correspond, respectively, to 314, 516, and 632 {\kms} (when convolved with the
observational uncertainties). Comparison with the observed RMS cluster velocity
of 29328 {\kms} further supports the low-density CDM model.Comment: revised version accepted for publication in ApJ Letters, 18 pages,
uuencoded PostScript with 3 figures included; complete paper available
through WWW at http://www.astro.princeton.edu/~library/prep.htm
SV-wave with external force in saturated medium
There are past researches done for SV-wave with the absence of external force. This work aims to investigate the influence of external force in the propagation of SV-wave in the soluble and insoluble mediums. Isotropic wave model is derived for SV-wave with various forces in accordance to Duhamel Principle and their analytical solutions are used to compare with each other’s’ amplitudes. With the existence of high density fluid, diffusive waves with larger external force will induce higher amplitude. However, SV-waves are non-diffusive in low density medium and hence, this work concludes that wave diffusion by external force is subjected to the properties of the targeted medium
Developmental research of sustainable technologies to minimise problematic road embankment settlements
Challenging, problematic and non-uniform ground conditions are a night mare to geotechnical engineers tasked with the design and construction of buildings and transport infrastructure. These often suffer undesirable structural settlements. Designing within the current understanding of geotechnics; settlement in peat and organic soils need to be recognised to include the known “primary and secondary consolidation characteristics” and the lesser known “tertiary consolidation phase”. These eventually contribute cumulatively to the consequential uneven and hazardous “bumpy road” surfaces. Undulating flexible road pavements result primarily from the transference of the heavy self-weight of the embankment fill to yielding and non-uniform subgrade. The adoption of conventional design/repair methods such as pile, vertical drain, soil replacement and soil stabilisation are expensive and inappropriate in very soft ground conditions. These then lead to unjustifiably high and repetitive maintenance costs. There being no one quick fix solution for all; pragmatic research must necessarily identify the best/progressively improved practical and sustainable solution. A viable solution is to develop criteria and explore the concept of a “masonry arch bridge structure/lintel-column structure” and adopting sustainable materials through pragmatic searching for appropriate recyclable waste materials. This will lead to the basis for a sustainable, innovative, strong, stiff, permeable composite mat structure that can be used on soft and/or yielding ground conditions. Conceptual lightweight fill technology including the popularly used expanded polystyrene (EPS) and the innovative composite mats recently being developed by the research team are outlined
Mindfulness, perceived partner responsiveness, and relationship quality:A dyadic longitudinal mediation model
Program Bantu Pemberian Kredit Mobil Studi Kasus : PT Adira Dinamika Multifinance – Bali
Kredit macet merupakan salah satu hal yang paling dihindari oleh Perusahaan-Perusahaan atau finance yang bergerak di bidang perkreditan, baik itu kredit mobil, kredit motor maupun kredit barang lainnya. PT Adira Dinamika Multifinance merupakan salah satu lembaga instansi yang bergerak dibidang pemberian kredit kendaraan bermotor, dan tidak pernah lepas dari kredit macet. Proses pemberian kredit kepada pelanggan adalah hal yang tidak gampang, karena harus mempertimbangkan berbagai faktor. Dari masalah tersebut penulis menerapkan aplikasi MCDM (Multi-Criteria Decision Making) untuk membuat Program Bantu Pemberian Kredit Mobil. Studi kasus penelitian ini dilakukan di PT Adira Dinamika Multifinance – Bali, dimana telah memiliki pola kebijakan tersendiri, yaitu menentukan siapa yang berhak menerima yang telah memenuhi syarat Five C, bagaimana karakter pelanggan dalam hal ini identitas(Character), jaminan yang dimiliki untuk menanggung resiko kredit(Collateral), kemampuan yang dimiliki pelanggan seperti pendapatan(Capital), kondisi keuangan, data keuangan pelanggan dalam hal ini seperti rekening tabungan pelanggan memilikinya atau tidak(Condition), dan kapasitas melunasi kredit dalam hal ini pekerjaan(Capacity). Program bantu pemberian kredit mobil menggunakan metode MCDM (Multi-Criteria Decision Making) akan memberikan alternatif pilihan dan kemungkinan solusi bagi Perusahaan untuk memilih pelanggan yang diterima permohonan kreditnya
Synthesis of Ultrafine Β′-Alumina Powders via Flame Spray Pyrolysis of Polymeric Precursors
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66387/1/j.1151-2916.1998.tb02506.x.pd
Data Quality Over Quantity: Pitfalls and Guidelines for Process Analytics
A significant portion of the effort involved in advanced process control,
process analytics, and machine learning involves acquiring and preparing data.
Literature often emphasizes increasingly complex modelling techniques with
incremental performance improvements. However, when industrial case studies are
published they often lack important details on data acquisition and
preparation. Although data pre-processing is unfairly maligned as trivial and
technically uninteresting, in practice it has an out-sized influence on the
success of real-world artificial intelligence applications. This work describes
best practices for acquiring and preparing operating data to pursue data-driven
modelling and control opportunities in industrial processes. We present
practical considerations for pre-processing industrial time series data to
inform the efficient development of reliable soft sensors that provide valuable
process insights.Comment: This work has been accepted to the 22nd IFAC World Congress 202
A contemporary assessment on composite titania onto graphitic carbon nitride-based catalyst as photocatalyst
Titanium dioxide (TiO2) has drawn widespread interest by researchers as a precious semiconductor that is responsive towards photodegradation of various pollutants. This catalyst has its own limitations such as fast electron-hole recombination, wide band gap, and can only be utilised under ultraviolet (UV) region. In order to overcome these problems, the addition of a metal-free dopant is a common practice to prevent electron-hole recombination and enhance photodegradation under visible light. Among various types of metal-free catalysts, carbon nitride material has received much attention due to its numerous benefits such as good in terms of physical and chemical strength, as well as an attractive electronic band combined with a band gap (2.7 eV). This review summarised recent works in the development of titania incorporated with graphitic carbon nitride (g-C3N4) for enhanced photocatalytic activity
Role of promoters in hoisting the catalytic performance for enhanced CO methanation
The increasing demand of natural gas and its rising cost have urged some countries to take initiatives to fulfil their energy needs. The production of substituted natural gas (SNG) by syngas (CO + H2) from coal or biomass is one of the most effective methods. As a promising source of energy, SNG has attracted much attention on research and applications due to the high demand for environmental protection. It is regarded as a clean energy source and an effective method for the application of coal resources, particularly in the regions with abundant coal resources but scarce natural gas such as in China [1-3]. SNG has attracted increasing attention due to its lower emission of sulphur and particulate matter. SNG is expected to be one of the main energy sources of the 21st century. It is environmentally friendly and less costly, has high calorific value, complete combustion, and smoke free compared to other energy sources. It has significant importance for the industrial level and transportation sectors
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