Crop-Animal Production Systems in Tropical Regions - Review -

Devendra, C. Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.2

Crop-animal systems which form the backbone of agriculture in the tropics are discussed with reference to their characteristics, economic importance of animals, genesis and types of crop-animal systems, relevance and potential importance, and priorities for research and development. These production systems are found across all agroecological zones: rain-fed temperate and highland systems, semi-arid and arid tropics, and sub-humid and humid tropics: the last four are priority areas in Asia. The potential importance of these systems in Asia is reflected in their advantages, synergism and complimentarity, economic benefits and contribution to sustainability. Illustrative case studies are cited which are appropriate to the two broad types of mixed farming systems: systems combining animals and annual cropping, and systems combining animals with perennial cropping with reference to Indonesia, Philippines, Malaysia, Sri Lanka, China and Nigeria. Priorities for research and development should address more complete use of the animal genetic resources, intensive utilisation of the feed resources, development-oriented utilisation of research results, minimizing animal diseases, and implementation of appropriate institutional and policy issues.

RELATIONS OF DAGUM DISTRIBUTION BASED ON DUAL GENERALIZED ORDER STATISTICS

Devendra Kumar 한국전산응용수학회 2017 Journal of applied mathematics & informatics Vol.35 No.5

The dual generalized order statistics is a unified model which contains the well known decreasingly ordered random variables like order statistics and lower record values. With this definition we give simple expressions for single and product moments of dual generalized order statistics from Dagum distribution. The results for order statistics and lower records are deduced from the relations derived and some computational works are also carried out. Further, a characterizing result of this distribution on using the conditional moment of the dual generalized order statistics is discussed. These recurrence relations enable computation of the means, variances and covariances of all order statistics for all sample sizes in a simple and efficient manner. By using these relations, we tabulate the means, variances, skewness and kurtosis of order statistics and record values of the Dagum distribution.

Retrieval of Distally Migrated Coils with Detachable Intracranial Stent during Coil Embolization of Cerebral Aneurysm

Devendra Pal Singh,Soon Chan Kwon,Lijin Huang,Won Joo Lee 대한뇌혈관외과학회 2016 Journal of Cerebrovascular and Endovascular Neuros Vol.18 No.1

Migration of coils during endovascular procedures is a rare, but well-known complication. We are reporting two cases of successfully retrieving migrated coil using detachable intracranial stent. In both of our cases there was distal migration of coil during the intracranial aneurysm coiling procedure. The Solitaire® AB stent (Covidien, Irvine, CA, USA) was used to retrieve those coils. The stent was passed distal to the migrated coil using standard technique. It was then partially deployed and gradually withdrawn along with the entangled coil. Coil retrieval using the fully retrievable intracranial stent is a very simple, safe and easily available alternative for retrieval of distally migrated coil.

Performance Enhancement of a Refrigerator Using Phase Change Material-Based Condenser: An Experimental Investigation

Devendra Dandotiya,N. D. Banker 대한설비공학회 2017 International Journal Of Air-Conditioning and Refr Vol.25 No.4

Tropical countries like India, the ambient temperature reaches to 45–50 ∘ C in the summer and higher ambient temperature directly impacts the energy required by the household refrigerator. This paper presents an experimental performance of a domestic refrigerator incorporated with a phase change material (PCM)-based condenser in parallel to the conventional wire-and-tube air-cooled condenser for the climatic conditions of India. It is proposed to operate the refrigerator with the PCM-based condenser, while the ambient temperature is higher during the day, otherwise with the air-cooled condenser. Due to large latent heat storage capacity of the PCM, the condenser temperature would not increase significantly. The COP of the PCM-based condenser was 28% higher as compared to air cooled condenser for 60 min which reduce to 3% as PCM temperature reached to 33 ∘C. The energy consumption is lower by ∼15 ∼15 % in 3 12 312h of refrigerator experimentation with the proposed modification.

Food-Feed Systems in Asia - Review -

Devendra, C.,Sevilla, C.,Pezo, D. Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.5

This review paper discusses the relevance and potential importance of food-feed systems in Asian agricultural systems, and in particular the role and contribution of legumes to these systems. A food-feed system is one that maintains, if not increases, the yield of food crops, sustains soil fertility, and provides dietary nutrients for animals. It involves a cropping pattern within which the feed crop has many beneficial effects without competing for land, soil nutrients and water with the food crops. The agricultural environment is described with reference to the priority agro-ecological zones and prevailing mixed farming systems in Asia. Within these systems, animal production is severely hampered by critical feed shortages which can however, be alleviated by the integration of suitable leguminous forages into the cropping systems. The review also focuses on the role and potential importance of leguminous forages in terms of biodiversity, their uses in farming systems, beneficial effects on animal performance, and draws attention to six case studies in different countries that clearly demonstrate many benefits of developing such food-feed systems. Considerable opportunities exist for widening the use of forage legumes in the development of systems with several complementary advantages (e.g. fenceline, cover crops, fodder banks, forage source and erosion control) to improve the development of sustainable crop-animal systems in Asia.

Analysis of Natural Mutant of Photoperiod Sensitive Genetic Male Sterile Japonica 920S under Different Photoperiods in Rice

Devendra Pandeya,서학수,강상구,Uck-Kee Baek 한국육종학회 2006 한국육종학회지 Vol.38 No.5

Photoperiod sensitive genetic male sterile (PGMS) rice 920S was characterized as sterile when it was grown under longday condition but fertile when grown under short day condition. PGMS rice 920S, F1 and F2 plants were examined for their fer-tilities under diferent photoperiods. All 920S parent plants were fertile in short photoperiod condition at 10 hrs day length, partialfertile in intermediate photoperiod condition at 13 hrs day length and sterile in long photoperiod condition at 14 hrs day length.antsshowed wide range of fertility with partial segregation of complete fertile, partial fertile, and complete sterile plants when theywere exposed to intermediate day length condition of 13 hrs day length. Therefore, here we suggest that there is a critical pho-toperiod to affect a PGMS gene that causes an alteration in fertility.

Smallholder Dairy Production Systems in Developing Countries : Characteristics, Potential and Opportunities for Improvement - Review -

Devendra, C. Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.1

Smallholder dairy production systems in developing countries are discussed with reference to type of systems, their characteristics, potential, and opportunities for improvement. Three types of dairy systems are identified and described: smallholder systems, smallholder cooperative dairy production systems, and intensive dairy production systems. The first two systems are by far the most important, and are associated with increasing intensification. Buffaloes are especially important in South Asia, but elsewhere dairy production mainly involves Holstein-Friesian cross-bred cattle. Dairy goats are important in some countries, but are generally neglected in development programmes. The expansion and intensification of smallholder dairy production is fueled by increased demand for milk with associated problems of milk handling and distribution, hygiene and environmental pollution. The major constraints to production are inter alia, choice of species, breeds and availability of animals; feed resources and improved feeding systems; improved breeding, reproduction, and animal health care; management of animal manure, and organised marketing, and market outlets. These constraints provide major opportunities and challenges for research and development to increase dairy production, efficient management of natural resources, and improved livelihoods of poor farmers. Specific areas for research are identified, as also the need of a holistic focus involving interdisciplinary research and integrated natural resource management, in a shared partnership between farmers and scientists that can demonstrate increased productivity and sustainable production systems. Suggestions for performance indicators in smallholder dairy production systems are indicated.

Integrated Tree Crops-ruminants Systems in South East Asia: Advances in Productivity Enhancement and Environmental Sustainability

Devendra, C. Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.5

Improved efficiency in the use of natural resources, pragmatic production systems and environmental sustainability, justified by the need for improved land use systems and increased productivity, are discussed in the context of Asian integrated systems, diversification, and issues of sustainability. The importance of these are reflected by serious inadequate animal protein production throughout Asia, where available supplies cannot match current and projected human requirements up to 2050. Among the ruminant production systems, integrated tree crops-ruminant production systems are grossly underestimated and merit emphasis and expansion. As an example, integrated oil palm- based system is an important pathway for integration with ruminants (buffaloes, cattle, goats and sheep), and provides the entry point for development. The importance and benefits of integrated systems are discussed, involving animals with annual and perennial tree crops, integration with aquaculture, the significance of crop-animal interactions, stratification of the systems, production options, improved use of forages and legumes, potential for enhanced productivity, implications for improved livelihoods of the rural poor and the stability of farm households. The advances in research and development in South East Asia highlight demonstrable increased productivity from animals and meat offtakes, value addition to the oil palm crop, sustainable development, and distinct economic impacts. The results from 12 out of a total of 24 case studies concerning oil palm over the past three decades showed increased yield of 0.49-3.52 mt of fresh fruit bunches (FFB)/ha/yr; increased income by about 30%; savings in weeding costs by 47- 60% equivalent to 21-62 RM/ha/yr; and an internal rate of return of 19% based on actual field data. The results provide important socio-economic benefits for resource-poor small farmers. Potential increased offtakes and additional income exist with the integration of goats. Additionally, the potential for carbon sequestration with tree crops is an advantage. The reasons for low adoption of the syatems are poor awareness of the potential of integrated systems, resistance by the crop- oriented plantation sector, and inadequate technology application. Promoting wider expansion and adoption of the systems in the future is linked directly with coherent policy, institutional commitment, increased investments, private sector involvement, and a stimulus package of incentives.

ON RELATIONS FOR QUOTIENT MOMENTS OF THE GENERALIZED PARETO DISTRIBUTION BASED ON RECORD VALUES AND A CHARACTERIZATION

Devendra Kumar 한국전산응용수학회 2013 Journal of applied mathematics & informatics Vol.31 No.3

Generalized Pareto distributions play an important role in reliability, extreme value theory, and other branches of applied probability and statistics. This family of distribution includes exponential distribution, Pareto distribution, and Power distribution. In this paper we establish some recurrences relations satisfied by the quotient moments of the upper record values from the generalized Pareto distribution. Further a characterization of this distribution based on recurrence relations of quotient moments of record values is presented.

MOMENTS OF LOWER GENERALIZED ORDER STATISTICS FROM DOUBLY TRUNCATED CONTINUOUS DISTRIBUTIONS AND A CHARACRERIZATIONS

Devendra Kumar 충청수학회 2013 충청수학회지 Vol.26 No.3

In this paper, we derive recurrence relations for moments of lower generalized order statistics within a class of doubly truncated distributions. Inverse Weibull, exponentiated Weibull,power function, exponentiated Pareto, exponentiated gamma, generalized exponential, exponentiated log-logistic, generalized inverse Weibull, extended type I generalized logistic, logistic and Gumble distributions are given as illustrative examples. Further, recurrence relations for moments of order statistics and lower record values are obtained as special cases of the lower generalized order statistics,also two theorems for characterizing the general form of distribution based on single moments of lower generalized order statistics are given.