Culture of air-breathing fishes

Though culture of fishes in ponds is one of the age old professions of the world, it is ga in ing prominence, because of the realisation that this source can supply rich and proteinaceous food for human consumption. Majority of the species selected from nature for rearing in ponds belong to the family of crops (Cyprinidae

Mathematical and Optimization Analysis of a Miniature Stirling Cryo-cooler

In the given report, a comprehensive analytical model of the working of a miniature Stirling Cyo-cooler is presented. The motivation of the study is to determine the optimum geometrical parameters of a cryo-cooler such as compressor length, regenerator diameter, expander diameter, and expander stroke. In the first part of the study, an ideal analysis is carried out using the Stirling Cycle and basic thermodynamics equations. Using these equations, rough geometrical parameters are found out. In the second part of the study, a more comprehensive Schmidt’s analysis is carried out. In this analysis, pressure and volume variations are considered sinusoidal and based on these, various equations regarding efficiency and COP are derived. Various graphs are generated in MATLAB plotting Refrigeration and Work done w.r.t to various geometrical parameters. With the help of these graphs, the net refrigeration obtained is calculated for a given geometry of cryo-cooler.. This model provides a more accurate picture of the cryo-cooler. However in this analysis, regenerator efficiency is considered 100 % which is not true in practical cases. In the third and final part of the study, optimization of regenerator is carried out. This part is based on Ackermann’s analysis in which various looses taking place inside a regenerator are considered and accounted for. These looses are minimized using an iterative cycle and optimum regenerator dimensions are obtained. Thus the geometrical results obtained from the third part of the study are expected to be most accurate as it accounts for most of the looses taking place inside a cryo-cooler

Fisheries environment in the APFIC region with particular emphasis on the northern Indian Ocean

The stocks of the small pelagics in the northern Indian Ocean are governed by different environmental jactors such as wind pattern, currents, convergence, temperature, salinjty, dissolved oxygen and vertical mixing processes. An attempt is made in this paper to correlate these factors with the fisheries for the small pelagics, In the northwest Pacific Ocean, successes or failures of recruitment of pelagic fishes are related to oceanographic factors, especially the direction of Kuroshio current. The information available on these aspects has been briefly reviewe

The New Economic Policy and Perspective for Marine Fisheries Research and Development in India

The New Economic Policy and Perspective for Marine Fisheries Research and Development in Indi

Some observations on the possibilities of culture of the Indian sand whiting Sillago sihama (Forskal) in brackish waters

Indian sand whiting, Sillago sihama (Forskal) forms a dominant species in the estuarine fish catches during the south-west monsoon when they are in great demand and fetch a high price as sea fishing remains suspended due to rough weather conditions. The paper deals with preliminary observations on certain aspects of the biology of the fish related to its culture. The ability of the species to withstand very wide raoges of salinity makes it suitable for culture io both brackish and fresh waters

Packages of Practices for Sustainable, Ecofriendly Mariculture (Land-based Saline Aquaculture and Seafarming)

The problems of fast growing human population and protein deficit, particularly in the developing countries continue to exert pressure on the fisheries resources available for exploitation in the wild water bodies. The increasingly limited opportunities in the capture fisheries sector have generated considerable interest in aquaculture

Ethnicity, popular democratic movements and labour in Malaysia

This article uses framing theory to examine how activists and trade unions have framed labour’s political agenda in Malaysia. A polity grounded in ethnicity continues to hinder the formation of cross-ethnic collective worker identities and labour politics. However, inclusive popular democratising movements have strengthened in recent years, providing a favourable context for greater emphasis on non-ethnic political action by trade unions. The latter have shifted in this direction, adopting elements of the popular movement’s ‘human rights’ internationalism. Thus, the democratic movement’s frame has influenced that of the trade unions, with implications for framing theory

Experimental and Numerical Studies on Setback Buildings Considering the SSI Effect under Seismic Response

From the previous studies it is observed that due to the effect of the earthquake, several irregular buildings failed vulnerably. Further the effect of sub soil conditions where these buildings have been founded also play an important role on the seismic response of these buildings. In the past, experimental studies on the seismic response of different setback building configurations have not been carried out. Therefore, in the present study the seismic behaviour of setback buildings considering Soil Structure Interaction (SSI) has been evaluated by conducting experimental and numerical investigations. Buildings with various setback configurations were considered and are designed as pile foundation supported structures. The irregularity index of these building configurations have been determined as per the existing codal provisions. These piles supported buildings representing the prototype structure have been scaled down according to geometric, kinematic and dynamic scaling laws. The scaled building models are subjected to vibrations beyond resonant frequencies using shake table facility. A comparison of the results has been made between experimental and numerical investigations. Based on the study it has been observed that storey displacements of building with regular configurations are higher in comparison with the setback buildings. It is also found that asymmetrical and symmetrical setback buildings having different irregularity indices as per IS:1893-2016 indicate nearly the same displacements at resonant frequencies. Doi: 10.28991/cej-2021-03091664 Full Text: PD

Fuzzy Knowledge Based System for Suitability of Soils in Airfield Applications

Proper design of roads and airfield pavements requires an in-depth soil properties evaluation to determine suitability of soil. Soft computing is used to model soil classification system's dynamic behaviour and its properties. Soft computing is based on methods of machine learning, fuzzy logic and artificial neural networks, expert systems, genetic algorithms. Fuzzy system is a strong method for mimicking human thought and solves question of confusion. This paper proposes a new decision-making approach for soil suitability in airfield applications without a need to perform any manual works like use of tables or chart. A fuzzy knowledge - based approach is built to rate soil suitability in qualitative terms for airfield application. The proposed model describes a new technique by defining fuzzy descriptors using triangular functions considering the index properties of soils as input parameters and fuzzy rules are generated using fuzzy operators to classify soil and rate its suitability for airfield applications. The data obtained from the results of the laboratory test are validated with the results of the fuzzy knowledge-based system indicating the applicability of the Fuzzy model created. The approach developed in this work is more skilled to other prevailing optimization models. Due to its system’s flexibility, it can be suitably customized and applied to laboratory test data available, thus delivering a wide range for any geotechnical engineer. Doi: 10.28991/cej-2021-03091643 Full Text: PD