562 research outputs found
Multiple-antenna-aided OFDM employing genetic-algorithm-assisted minimum bit error rate multiuser detection
The family of minimum bit error rate (MBER) multiuser detectors (MUD) is capable of outperforming the classic minimum mean-squared error (MMSE) MUD in terms of the achievable bit-error rate (BER) owing to directly minimizing the BER cost function. In this paper,wewill invoke genetic algorithms (GAs) for finding the optimum weight vectors of the MBER MUD in the context of multiple-antenna-aided multiuser orthogonal frequency division multiplexing (OFDM) .We will also show that the MBER MUD is capable of supporting more users than the number of receiver antennas available, while outperforming the MMSE MUD
Curvature estimates for submanifolds in warped products
We give estimates on the intrinsic and the extrinsic curvature of manifolds
that are isometrically immersed as cylindrically bounded submanifolds of warped
products. We also address extensions of the results in the case of submanifolds
of the total space of a Riemannian submersion.Comment: 21 page
Efficient Algorithms for Asymptotic Bounds on Termination Time in VASS
Vector Addition Systems with States (VASS) provide a well-known and
fundamental model for the analysis of concurrent processes, parameterized
systems, and are also used as abstract models of programs in resource bound
analysis. In this paper we study the problem of obtaining asymptotic bounds on
the termination time of a given VASS. In particular, we focus on the
practically important case of obtaining polynomial bounds on termination time.
Our main contributions are as follows: First, we present a polynomial-time
algorithm for deciding whether a given VASS has a linear asymptotic complexity.
We also show that if the complexity of a VASS is not linear, it is at least
quadratic. Second, we classify VASS according to quantitative properties of
their cycles. We show that certain singularities in these properties are the
key reason for non-polynomial asymptotic complexity of VASS. In absence of
singularities, we show that the asymptotic complexity is always polynomial and
of the form , for some integer , where is the
dimension of the VASS. We present a polynomial-time algorithm computing the
optimal . For general VASS, the same algorithm, which is based on a complete
technique for the construction of ranking functions in VASS, produces a valid
lower bound, i.e., a such that the termination complexity is .
Our results are based on new insights into the geometry of VASS dynamics, which
hold the potential for further applicability to VASS analysis.Comment: arXiv admin note: text overlap with arXiv:1708.0925
Role of chondroitin sulfate proteoglycans (CSPGs) in synaptic plasticity and neurotransmission in mammalian spinal cord.
Chronic unilateral hemisection (HX) of the adult rat spinal cord diminishes conduction through intact fibers in the ventrolateral funiculus (VLF) contralateral to HX. Intraspinal injections of Chondroitinase-ABC, known to digest chondroitin sulfate proteoglycans (CSPGs) in the vicinity of injury, prevented this decline of axonal conduction. This was associated with improved locomotor function. We further injected three purified CSPGs into the lateral column of the uninjured cord at T10: NG2 and neurocan, which increase in the vicinity of a spinal injury, and aggrecan, which decreases. Intraspinal injection of NG2 acutely depressed axonal conduction through the injection region in a dose dependent manner. Similar injections of saline, aggrecan, or neurocan had no significant effect. These results identify a novel acute action of CSPGs on axonal conduction in spinal cord, and suggest that antagonism of proteoglycans reverses or prevents the decline of axonal conduction, in addition to stimulating axonal growth
Akselerasi moulting larva udang Vaname (Litopenaeus vannamei) dengan pemberian kalsium hidroksida Ca(OH)2
Kualitas dan pertumbuhan larva udang vaname sangat dipengaruhi oleh proses dan frekuensi molting, dimana pertumbuhan erat kaitannya dengan proses pergantian cangkang. Kalsium hidroksida Ca(OH)2 merupakan salah satu mineral kalsium yang berhubungan dengan kadar kalsium kulit dan kadar kalsium lingkungan seiring pertukaran kalsium secara terus-menerus antara tubuh dan lingkungan. Tujuan penelitian ini adalah mengevaluasi akselerasi dan frekuensi molting larva udang vaname serta pengaruh lanjut Kalsium Hidroksida Ca(OH)2 terhadap laju pertumbuhan larva udang vaname. Desain penelitian adalah eksperimental menggunakan Rancangan Acak Lengkap dengan 4 taraf dosis Ca(OH)2 : A. Tanpa penambahan Ca(OH)2 (kontrol), B. 2 mg/ L air, C. 4 mg/ L air, dan D. 6 mg/L air. Hasil penelitian menunjukkan bahwa dosis Ca(OH)2 sebanyak 4 mg/L air menunjukkan intensitas/persentase molting sebesar 67%, laju pertumbuhan berat mutlak sebesar 2.35 mg, pertumbuhan panjang mutlak sebesar 4,93 mm, dan tingkat kelulushidupan udang (SR) sebesar 49%
Digitizing radiology films using flat-bed scanner and produce a multimedia digital teaching file in musculoskeletal radiology
Digital images have been long established in radiology department. Despite this, most radiology teaching films has been film-based. The drawback of this conventional system is that it consumed space, only one user can use at any one time and expensive. Analogue radiology films were digitized using flatbed scanner with transparency adaptor and digital camera. Digital-based teaching files using personal computer (PC) should be encouraged as this will reduce space for storing, can be distributed without much cost, inexpensive, many users can use at the same time and others can use even though at different place using the internet. The teaching file was prepared using HyperText Mark-up Language (HTML) as this can be used using any web browser. It is now available in University Sains Malaysia, Kelantan Campus Branch (USMKCK) intranet
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