Development of artificial feeds for finfishes

successful fish culture depends upon provision of diets coritaining an appropriate balance of essential nutrients and adequate level of energy to permit the most efficient growth of fish. Application of modern techniques, with very high production potentials, demands supply of nutritionally balanced complete feeds in intensive sys-tems and suppLemental feeds in semi-intensive system

Vitamin requirements of finfish and prawns

Vitamins are complex organic substances, usually of comparatively small molecular size (molecular weight usually less than 1000). They are distributed in feedstuffs in small quantities and form a distinct entity from other major and minor food components (Cho et a_l., 1985). The importance of vitamins as essential constituents in the diets of animals came to light in the early part of this century and during the past five decades active and rapid progress in vitamin research was made almost in all the coMmercially important specie

Feed ingredients available in India and their potential nutritional value

Development of practical feed formulations depend upon information on two major aspects; the nutritional requirements of the animals and the nutritive value of the potential feed ingredients. Once information on these aspects along with other essential parameters, become available for a specific species and size, it should be possible to develop low-cost practical feeds using linear programming. During the past two decades there has been a phenomenal increase in research activities relating to identification of raw materials for formulating feed ingredients both in the developed and developing nations of the world

Classification of Malaysian vowels using formant based features

Automatic speech recognition (ASR) has made great strides with the development of digital signal processing hardware and software, especially using English as the language of choice. Despite of all these advances, machines cannot match the performance of their human counterparts in terms of accuracy and speed, especially in case of speaker independent speech recognition. In this paper, a new feature based on formant is presented and evaluated on Malaysian spoken vowels. These features were classified and used to identify vowels recorded from 80 Malaysian speakers. A back propagation neural network (BPNN) model was developed to classify the vowels. Six formant features were evaluated, which were the first three formant frequencies and the distances between each of them. Results, showed that overall vowel classification rate of these three formant combinations are comparatively the same but differs in terms of individual vowel classification

Achievable and Crystallized Rate Regions of the Interference Channel with Interference as Noise

The interference channel achievable rate region is presented when the interference is treated as noise. The formulation starts with the 2-user channel, and then extends the results to the n-user case. The rate region is found to be the convex hull of the union of n power control rate regions, where each power control rate region is upperbounded by a (n-1)-dimensional hyper-surface characterized by having one of the transmitters transmitting at full power. The convex hull operation lends itself to a time-sharing operation depending on the convexity behavior of those hyper-surfaces. In order to know when to use time-sharing rather than power control, the paper studies the hyper-surfaces convexity behavior in details for the 2-user channel with specific results pertaining to the symmetric channel. It is observed that most of the achievable rate region can be covered by using simple On/Off binary power control in conjunction with time-sharing. The binary power control creates several corner points in the n-dimensional space. The crystallized rate region, named after its resulting crystal shape, is hence presented as the time-sharing convex hull imposed onto those corner points; thereby offering a viable new perspective of looking at the achievable rate region of the interference channel.Comment: 28 pages, 12 figures, to appear in IEEE Transactions of Wireless Communicatio

Nutrition in aquaculture - An overview

Aquaculture is gaining more and more importance as a means to augment finfish and shellfish production in both the developed and developing countries of the world, to partially meet the growing demand for fish and shellfish protein. It has been predicated by TAG (1973) that by the year 2000, aquaculture could produce at least 50 million tons of animal protein, if certain research and development measures are undertaken, as against the production of 6 million tons of fish and shellfish through culture in 1975 (Pillay, 1976)

Fish nutrition and climate change. In: Winter School on Impact of Climate Change on Indian Marine Fisheries held at CMFRI, Cochin 18.1.2008 to 7.2.2008

Fish production, whether in the natural or captive aquatic ecosystems, largely depends on a reliable supply of nutritious food preferred by the different life-stages of a species and congenial environmental conditions that stimulate optimum intake, digestion and utilization of the food. Fish being ectotherms their survival, growth and reproduction are greatly influenced by changes in water temperature besides synergetic effect of several other physico-chemical factors prevailing in the aquatic environment. In this article, an attempt is made to highlight the basic nutritional needs of marine, and freshwater fish, and the likely impacts of climate change, especially the role of temperature on intake and utilization of food nutrients by fish

Delivery Time Minimization in Edge Caching: Synergistic Benefits of Subspace Alignment and Zero Forcing

An emerging trend of next generation communication systems is to provide network edges with additional capabilities such as additional storage resources in the form of caches to reduce file delivery latency. To investigate this aspect, we study the fundamental limits of a cache-aided wireless network consisting of one central base station, $M$ transceivers and $K$ receivers from a latency-centric perspective. We use the normalized delivery time (NDT) to capture the per-bit latency for the worst-case file request pattern at high signal-to-noise ratios (SNR), normalized with respect to a reference interference-free system with unlimited transceiver cache capabilities. For various special cases with $M=\{1,2\}$ and $K=\{1,2,3\}$ that satisfy $M+K\leq 4$, we establish the optimal tradeoff between cache storage and latency. This is facilitated through establishing a novel converse (for arbitrary $M$ and $K$) and an achievability scheme on the NDT. Our achievability scheme is a synergistic combination of multicasting, zero-forcing beamforming and interference alignment.Comment: submitted to ICC 2018; fixed some typo

On the ergodic sum-rate performance of CDD in multi-user systems

The main focus of space-time coding design and analysis for MIMO systems has been so far focused on single-user systems. For single-user systems, transmit diversity schemes suffer a loss in spectral efficiency if the receiver is equipped with more than one antenna, making them unsuitable for high rate transmission. One such transmit diversity scheme is the cyclic delay diversity code (CDD). The advantage of CDD over other diversity schemes such as orthogonal space-time block codes (OSTBC) is that a code rate of one and delay optimality are achieved independent of the number of transmit antennas. In this work we analyze the ergodic rate of a multi-user multiple access channel (MAC) with each user applying such a cyclic delay diversity (CDD) code. We derive closed form expressions for the ergodic sum-rate of multi-user CDD and compare it with the sum-capacity. We study the ergodic rate region and show that in contrast to what is conventionally known regarding the single-user case, transmit diversity schemes are viable candidates for high rate transmission in multi-user systems. Finally, our theoretical findings are illustrated by numerical simulation results.Comment: to appear in Proceedings of 2007 IEEE Information Theory Workshop (ITW) in Lake Taho