bluuebunny/crossref_metadata_2025_split huggingface dataset:
The comparative energetics and growth strategies of sympatric Antarctic and subantarctic fur seal pups at Îles Crozet
Authors: Arnould J. P. Y. , Luque S. P. , Guinet C. , Costa D. P. , Kingston J. , Shaffer S. A. 
Published: November 2003

SUMMARYThe period of maternal dependence is a time during which mammalian infants must optimise both their growth and the development of behavioural skills in order to successfully meet the demands of independent living. The rate and duration of maternal provisioning, post-weaning food availability and climatic conditions are all factors likely to influence the growth strategies of infants. While numerous studies have documented differences in growth strategies at high taxonomic levels, few have investigated those of closely related species inhabiting similar environments. The present study examined the body composition, metabolism and indices of physiological development in pups of Antarctic fur seals (Arctocephalus gazella) and subantarctic fur seals (Arctocephalus tropicalis), congeneric species with different weaning ages (4 months and 10 months, respectively), during their overlap in lactation at a sympatric breeding site in the Iles Crozet. Body lipid reserves in pre-moult pups were significantly greater(t28=2.73, P&lt;0.01) in subantarctic (26%) than Antarctic fur seals (22%). Antarctic fur seal pups, however, had significantly higher (t26=3.82, P&lt;0.001) in-air resting metabolic rates (RMR; 17.1±0.6 ml O2 kg-1min-1) than subantarctic fur seal pups (14.1±0.5 ml O2 kg-1 min-1). While in-water standard metabolic rate (SMR; 22.9±2.5 ml O2 kg-1min-1) was greater than in-air RMR for Antarctic fur seal pups(t9=2.59, P&lt;0.03), there were no significant differences between in-air RMR and in-water SMR for subantarctic fur seal pups(t12=0.82, P&gt;0.4), although this is unlikely to reflect a greater ability for pre-moult pups of the latter species to thermoregulate in water. Pup daily energy expenditure was also significantly greater (t27=2.36, P&lt;0.03) in Antarctic fur seals (638±33 kJ kg-1 day-1) than in subantarctic fur seals (533±33 kJ kg-1 day-1), which corroborates observations that pups of the former species spend considerably more time actively learning to swim and dive. Consistent with this observation is the finding that blood oxygen storage capacity was significantly greater(t9=2.81, P&lt;0.03) in Antarctic (11.5%) than subantarctic fur seal (8.9%) pups. These results suggest that, compared with subantarctic fur seals, Antarctic fur seal pups adopt a strategy of faster lean growth and physiological development, coupled with greater amounts of metabolically expensive behavioural activity, in order to acquire the necessary foraging skills in time for their younger weaning age.
Influence of salinity on the localization of Na+/K+-ATPase,Na+/K+/2Cl- cotransporter (NKCC) and CFTR anion channel in chloride cells of the Hawaiian goby (Stenogobius hawaiiensis)
Authors: McCormick Stephen D. , Sundell Kristina , Björnsson Björn Thrandur , Brown Christopher L. , Hiroi Junya 
Published: November 2003

SUMMARY
Na+/K+-ATPase,Na+/K+/2Cl- cotransporter (NKCC) and cystic fibrosis transmembrane conductance regulator (CFTR) are the three major transport proteins thought to be involved in chloride secretion in teleost fish. If this is the case, the levels of these transporters should be high in chloride cells of seawater-acclimated fish. We therefore examined the influence of salinity on immunolocalization of Na+/K+-ATPase, NKCC and CFTR in the gills of the Hawaiian goby (Stenogobius hawaiiensis). Fish were acclimated to freshwater and 20‰ and 30‰ seawater for 10 days. Na+/K+-ATPase and NKCC were localized specifically to chloride cells and stained throughout most of the cell except for the nucleus and the most apical region, indicating a basolateral/tubular distribution. All Na+/K+-ATPase-positive chloride cells were also positive for NKCC in all salinities. Salinity caused a slight increase in chloride cell number and size and a slight decrease in staining intensity for Na+/K+-ATPase and NKCC, but the basic pattern of localization was not altered. Gill Na+/K+-ATPase activity was also not affected by salinity. CFTR was localized to the apical surface of chloride cells, and only cells staining positive for Na+/K+-ATPase were CFTR-positive. CFTR-positive cells greatly increased in number (5-fold), area stained (53%) and intensity (29%)after seawater acclimation. In freshwater, CFTR immunoreactivity was light and occurred over a broad apical surface on chloride cells, whereas in seawater there was intense immunoreactivity around the apical pit (which was often punctate in appearance) and a light subapical staining. The results indicate that Na+/K+-ATPase, NKCC and CFTR are all present in chloride cells and support current models that all three are responsible for chloride secretion by chloride cells of teleost fish.
Organic–Inorganic Cooperative Molecular Recognition in Nanostructure of Alkyl-grafted MCM-41
Authors: Inumaru Kei , Inoue Yuta , Kakii Shintaro , Nakano Tomoyasu , Yamanaka Shoji 
Published: November 2003

Abstract
Molecules having hydrophobic and hydrophilic groups such as 4-n-heptylaniline and 4-nonylphenol, an endocrine disrupter, fit the organic–inorganic nanostructure in alkyl-grafted MCM-41, interacting with the inorganic walls as well as the organic moiety, and thus the adsorbent achieves high molecular adsorption selectivity.
Preparation of Gold Nanoplates by a Microwave-polyol Method
Authors: Tsuji Masaharu , Hashimoto Masayuki , Nishizawa Yuki , Tsuji Takeshi 
Published: November 2003

Abstract
Triangular, square, and hexagonal gold nanoplates with diameters of 30–90 nm have been prepared through a microwave-polyol method. These nanoplates gave new plasmon band of Au in the 550–800 nm region. It was concluded that nonthermal effect plays a significant role for the formation of Au nanoplates under microwave irradiation.
Inclusion Complex Formation and Hydrolysis of Lactones by Cyclodextrins
Authors: Takashima Yoshinori , Kawaguchi Yoshinori , Nakagawa Shinya , Harada Akira 
Published: November 2003

Abstract
Cyclodextrins (CDs) have been found to form inclusion complexes with lactones in aqueous solutions and/or in the solid states; hydrolysis of lactones has been found to be suppressed or promoted by CDs according to the combination of lactones and CD.
Synthesis and Characterization of Ni(OH)2 Single-crystal Nanorods
Authors: Liang Jiahe , Li Yadong 
Published: November 2003

Abstract
A template-free hydrothermal method to Ni(OH)2 single-crystal nanorods were successfully established based on the 2-D layered structures of Ni(OH)2. The obtained Ni(OH)2 nanorods were 40–90 nm in diameters and 1–3 μm in lengths. It is interesting that Ni(OH)2 nanorods would be converted into NiO nanorings when they were annealed at 500 °C for 6 h.
Coding for Magnetic Recording Channels
Authors: Weng Lih‐Jyh 
Published: November 2003

Abstract
A brief history of coding approaches employed in magnetic recording disk drives is first reviewed. This is followed by a simple example of using the most widely used Reed‐Solomon codes to illustrate the concepts and terminology frequently used in disk drives. Important considerations in selecting appropriate decoding algorithm are explained. Implementation issues are discussed. Synchronization techniques, code performance based on error rate computation, interleaving of code block within a recording sector, and error‐detecting code issues are also addressed. Finally, coding approaches for magnetic tape drives and RAID systems are discussed.
Surface Acoustic Wave Filters
Authors: Das Pankaj K. , Filkins Robert J. 
Published: November 2003

AbstractSurface acoustic wave filters are an essential part of many telecommunication systems, from cell phones to GPS receivers. This chapter presents the fundamentals of surface acoustic wave device operation and their application to telecommunication systems. The main types of ultrasonic acoustic waves are described, followed by a discussion of the device building blocks. Next, the design of surface acoustic wave filters is outlined, and specific design examples are given. Finally, several detailed application examples are provided, summarizing the use of surface acoustic filters in telecommunication systems.
Very High‐Speed Digital Subscriber Lines (VDSLs)
Authors: Cioffi J. 
Published: November 2003

AbstractVery high‐speed Digital Subscriber Lines (VDSL) is the most recent in VDSL service offerings, allowing speeds to many tens of megabits per second in both directions on a single phone line of length less than 2 km. This chapter overviews VDSL history and standards while also describing some of the key technologies used at the implementation level. Some reference to the emerging VDSL application area of Ethernet‐in‐the‐First‐Mile (EFM) is also provided.
Orthogonal Frequency‐Division Multiplexing
Authors: Cimini Leonard J. , Greenstein Larry J. 
Published: November 2003

AbstractThe permissible data rate of a digital communications link is limited by the available bandwidth and also by power and noise. We present the basic concepts and then discuss the numerous communications systems, past and present, that have used some form of multicarrier transmission. We then discuss time variations in the channel, as well as frequency offset, phase noise, and timing errors. Next, we the look at the large amplitude fluctuations characteristic of a multicarrier signal and the serious problems when transmitting through a nonlinearity, such as the transmit power amplifier. Finally, we discuss cyclic extension and windowing, two techniques devised to get the most value out of orthogonal frequency‐division multiplexing (OFDM).
Blind Multiuser Detection
Authors: Wang Xiaodong 
Published: November 2003

Abstract
There are primarily two approaches to blind multiuser detection, namely, the direct matrix inversion (DMI) approach and the subspace approach. In this article, we present batch algorithms and adaptive algorithms under both approaches. We first treat the simple synchronous CDMA channels and present the main techniques for blind multiuser detection. We then generalize these methods to the more general asynchronous CDMA channels with multipath effects.
Atmospheric Radiowave Propagation
Authors: Raemer Harold 
Published: November 2003

AbstractThis article is a brief summary of the mode of radio wave propagation that is used in wireless communication systems operating at frequencies between 300 MHz and 30 GHz. It begins with a discussion of line‐of‐sight propagation in free‐space, then examines the effects on the propagating waves of reflection from the earth's surface, the earth's curvature, and atmospheric refraction and attenuation. Next we discuss the effects of surface roughness and the presence of natural and man‐made obstacles in the propagation path, which causes diffraction and scattering of the waves. The remaining portion of the article covers propagation models which have been useful in prediction of path losses for planning and design of wireless links, and which contain many of the phenomena mentioned above. The article includes many references on the topics covered and on some topics that are only briefly mentioned.
Cellular Communications Channels
Authors: Mämmelä Aarne , Järvensivu Pertti 
Published: November 2003

Abstract
Linear channel models for terrestrial outdoor mobile cellular systems including multipath fading and shadowing are summarized in this chapter. In microcells the cell radius is about 0.1 km to 1 km and in macrocells the cell radius is about 1 km to 30 km. Such systems typically work in the frequency range from about 1 GHz to 2 GHz. The bandwidth of the transmitted signals is in the order of 100 kHz to 1 MHz. The second order statistics of the typical Rayleigh fading wide‐sense stationary uncorrelated scattering (WSSUS) channel are described by the scattering function, which is the average power output as a function of the time delay and the Doppler shift parameter. The amplitudes of the multipath components can also be assumed to be Ricean or Nakagami‐m distributed. Shadowing is normally assumed to be lognormal. The results are generalized to the two‐dimensional case where the direction of arrival is included in addition to the delay. The channel impulse response is measured usually by using m‐sequences and correlation. Most practical channels are shown to be measurable. Measurements show that the the delay spreads in urban areas are from 1 ms to 2 ms and in mountainous areas from 100 ms to 150 ms. The Doppler spread depends on the carrier frequency and the velocity of the mobile station. Channel simulators are based on either stored channel impulse responses, ray tracing models or stochastic parametric models, and they are implemented by hardware or software by using transversal filters. Models are specified by different standardization organizations. At the end of the chapter recent trends are summarized, including larger carrier frequencies, increased bandwidths, three‐dimensional and nonstationary models, and models with multiple inputs and outputs.
HiddenMarkov Models
Authors: Juang Biing‐Hwang 
Published: November 2003

AbstractA hidden Markov model is a mathematical formalism that allows modeling of a stochastic system, which may undergo characteristic changes at uncertain times. It is often called a doubly stochastic process in which a Markov chain governs the characteristic change of the system and each state of the Markov chain is associated with a stochastic process or distribution, which supports the random nature of the observation. The formalism is also referred to asprobabilistic functions of Markov processes. In this article, we define this stochastic modeling technique, elaborate its key problems and solutions, and show, as a simple example, how this technique can be applied to real‐world problems such as automatic speech recognition for communication services.
Image Processing
Authors: Bystrom Maja 
Published: November 2003

Abstract
Image processing can be loosely subdivided into a number of fields: acquisition, analysis, compression, reconstruction, watermarking and data hiding. Within the field of image acquisition, methods of image representation are discussed. The broad topic of filtering is presented as a tool for many of the processing techniques, and measures of image quality are given. Particular attention is paid to the common image transformations, the discrete cosine transform and the discrete wavelet transform. Analysis and segmentation of images, that is, recognition of pertinent features or characteristics, and the division of an image based upon features are discussed. Finally, the field of watermarking and data hiding as a means of protecting ownership or transferring information is presented.
BCH
Codes—Nonbinary And Reed‐Solomon*
Authors: Michelson Arnold M. , Levesque Allen H. 
Published: November 2003

Abstract
The description of nonbinary BCH codes closely follows the presentation for binary BCH codes in the preceding article. Nonbinary BCH codes are described as cyclic codes whose generator polynomials have particular sequences of roots. Reed Solomon codes are defined as nonbinary BCH codes whose symbol and locator fields are the same. Efficient encoding and decoding algorithms are described for hard‐decision and errors‐and‐erasures decoding. More general soft‐decision decoding schemes are discussed.
Cyclic Codes
Authors: Wicker Stephen B. 
Published: November 2003

AbstractCyclic codes are a class of highly structured algebraic block error control codes. We begin with an historical overview of the various subclasses of cyclic codes. We then provide a brief overview of the general theory of cyclic codes, and then turn to the three important classes (the Golay codes, BCH, and Reed‐Solomon codes). The article concludes with a discussion of several important applications.
Finite‐Geometry Codes
Authors: Fossorier M. 
Published: November 2003

Abstract
In this article, the constructions of linear block codes based on finite geometries are introduced. These finite geometry codes are related to another class of codes, namely low density parity check (LDPC) codes. The decoding of finite geometry codes exploiting the structure of finite geometries as well as methods developed for LDPC codes is then described.
Speech Perception
Authors: Müsch Hannes , Buus Søren 
Published: November 2003

AbstractSpeech is probably one of the oldest methods of communication. A large amount of research reveals a multitude of factors that are important for speech intelligibility. This article presents these factors, especially those that are important for the design of communication systems. A brief description of the speech signal is followed by a brief discussion of some basic properties of speech perception and an overview of some theories that have been proposed to account for them.
Hadamard Matrices and Codes
Authors: Bossert Martin 
Published: November 2003

AbstractHadamard matrices were born as a theoretical topic in combinatorics and have found various applications in different fields. In this article we present the definition and two possible constructions of Hadamard matrices, namely, the Sylvester and the Payley constructions. Next, we describe the connections to coding theory and then derive the fast Hadamard transform for signal processing. Finally, we comment on several applications.
Simulation of Communication Systems
Authors: Shanmugan K. Sam 
Published: November 2003

Abstract
Simulation plays an important role in the design, analysis, and implementation of communication systems. During the design of complex communication systems it is often infeasible to conduct performance analysis and design tradeoff studies using closed‐form mathematical formula techniques. Quite frequently, simulation is the only tool available for addressing important issues in the design, analysis, and implementation of communication systems. Simulation can be used to verify the functionality of communication systems, evaluate the performance of proposed systems, and generate specifications to guide their design. Since the early 1980s a variety of modeling and simulation techniques and tools have been developed and used to support the design and implementation of a broad range of communication systems and products ranging from multi‐million‐dollar communication satellites to handsets for the next generation of personal communication systems. This article presents an overview of the fundamental principles behind modeling and simulation of communication systems.
Time Division Multiple Access (
TDMA
)
Authors: Jung Peter 
Published: November 2003

Abstract
In this communication, a concise overview of TDMA (time division multiple access) and its application to mobile communications shall be presented. It shall be motivated that TDMA, being a means of medium access control (MAC), facilitates both a high spectral capacity and a reasonably low implementation complexity. Finally, a further evolution of TDMA based systems toward the combination with CDMA (code division multiple access) will be illustrated. This combination became part of UMTS (universal mobile telecommunication system), known as UTRA TDD (UMTS terrestrial radio access time domain duplex) or TD/CDMA.
Space–Time Codes for Wireless Communications
Authors: Al‐Dhahir Naofal , Calderbank A. R. , F. Naguib Ayman 
Published: November 2003

AbstractSpace‐Time Coding is a new coding/signal processing framework for wireless communications systems with multiple transmit/receive antennas. This new framework offers the best tradeoff between spectral efficiency and power consumption by optimum combination of modulation, coding, and diversity gains over flat‐fading channels.Space‐time trellis codes offer the maximum possible diversity and coding gains without any sacrifice in transmission bandwidth. Their decoding requires a vector Viterbi algorithm. Alamouti‐type Space‐time block codes offer maximum diversity gain, much lower decoding complexity, and full rate transmission but sacrifice coding gain. The first part of this article reviews the fundamentals of space‐time coding for frequency‐flat fading channels.For frequency‐selective fading channels, we describe, in the second part of the article, several competitive joint equalization and decoding schemes for space‐time codes that further exploit the temporal diversity of the channel. Channel estimation issues are also discussed. Exploiting the rich structure of space‐time codes is critical in simplifying the channel estimation, equalization, and decoding schemes.
Speech Processing
Authors: O'Shaughnessy Douglas 
Published: November 2003

Abstract
Synthetic speech conveys information to listeners in a convenient verbal way. It uses a computer program and stored portions of speech to formulate the synthetic voice. Its naturalness depends on the vocabulary of words to speak, the size of the stored speech, and the complexity of the synthesis programs. Simple voice response just plays back short copies of human speech signals, stored using digital sampling technology. More powerful systems can transform any text into comprehensible speech for various languages. So far such speech is usually intelligible, but often sounds less natural than human speech.
Code‐Division Multiple Access
Authors: Vojčić Branimir R. , Pickholtz Raymond L. 
Published: November 2003

AbstractIn this article basic principles of direct sequence spread spectrum for code division multiple access (CDMA) are described. CDMA is evolving into dominant multiple access technology for commercial wireless communications. Performance of conventional detection in CDMA is discussed, as well as the impact of imperfect power control. Several multiuser detection schemes that could improve the performance and enable robust operation in the presence of power control error are reviewed.
Continuous‐Phase‐Coded Modulation
Authors: Sundberg Carl‐Erik W. , Anderson John B. 
Published: November 2003

AbstractContinuous Phase Modulation (CPM) is a class of constant amplitude digital modulation schemes which has both good power and band width efficiency. Memory is introduced in the signal by means of a continuous phase. This principle results in smooth power spectra with low spectral sidelobes. The continuous phase can also be exploited in detection over multiple digital symbols yielding lower bit error probability. Increased memory can be obtained by so called partial response techniques and combinations with convolutional codes. In this paper we give a brief overview of performance of various CPM systems. Comparisons are made with minimum shift keying (MSK) and Gaussian minimum shift keying (GMSK) systems. We show the existence of considerably better CPM schemes than these two reference systems. Receiver and transmitter structures are also discussed.
Automatic Repeat Request
Authors: Fuja Thomas E. 
Published: November 2003

Abstract
This article describes automatic repeat request (ARQ), a technique for improving the reliability of digitally‐transmitted data through the re‐transmission of corrupt frames. It begins by describing the use of cyclic redundancy check (CRC) codes to detect the presence of errors in received data. It then describes three protocols through which the transmitter and receiver coordinate the re‐transmission procedure; those protocols are “Stop‐and‐Wait,” “Go‐Back‐N”, and “Selective Repeat.” These three re‐transmission strategies are briefly analyzed in terms of their efficiency (“throughput”) and reliability (“frame error rate”). Finally, hybrid ARQ schemes, which incorporate both re‐transmission (ARQ) and forward‐error control (FEC) techniques, are discussed.