• 건축역사연구
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• 제18권6호
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• pp.103-126
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• 2009

This study aims to discover historical trends and change of form of all stupas in India with observation of field study that is as direct as possible, by classifying, analyzing, and synthesizing the stupas. Study of Indian stupa in Korea has a number of shortcomings since only introductory partial approach has been made in order to seek the origin of Korean pagoda. This study also aims to correct errors of stupa terminology in Chinese character committed by misinterpretation of Hindi language which was established by precedent Japanese scholars several decades ago. Piled-up stupas were totally destroyed by pagans, therefore their remains tell us only of structure, material, sizeand disposition. However remains of carved stone at torana and drum give us clues as to the original form of stupa and worshipping activity, as well as change to a more luxurious form. Many rock cave stupas of India show us both simple forms matching the ascetic age of early Buddhism and luxurious changes in Mahayanan era introducing us to statues of Buddha. Indians recovered the spheric form of 'anda,' a Hindi term meaning cosmic egg, from the hemispheric form of the piled-up stupa. Therefore we might discard the erratic term of 'bokbal', which means an upset vessel. Railings and parasols became main factors of stupa design. Carved railings around stupa became a sign of divinity. Serious worshipping activity made drums long or high and created multi-embossed stripes. Bases of circular drums of some cave stupas changed their shapes to rectangular or octagonal. Single parasols became multiparasols of affluent flowerlike curved stems on carved stupa. Multistoried, elongated and high parasols of Gandhara stupas are closely related to such factors as diverse changes of form in Indian subcontinent. Four-sided torana gate and ayaka column of the circular form of original stupas suggest the rectangular form of subsequent East Asian pagoda, and higher and wider base of Indian stupas became the origin of East Asian rectangular pagoda.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.637-647
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• 1993

Over 40 per cent Indian population needs to be attended for nutritional improvement. Traditional nutritious food resources though abundantly available but presently less used, if incorporated in the diets, can yield low-cost nutritionally balanced diets. The linear programming (LP)model was used for optimization of food resources to satisfy protein -energy requirements of hard working rural poor. Soybean-a highly nutritious food legume-available at reasonably low price was included along with chick -pea and pigeon -pea for comparison .The three cereals predominantly used in Indian diets -rice, wheat and sorghum -and three typical leafy vegetables namely, spinach , drumstick leaves and rajagira (Amaranths paniculantus) leaves were used for optimization . The contribution of food legume was restricted to supply only 50 per cent of daily protein requirement for maximum protein value. The quantities of other food stuffs namely , milk , sugar , tubers etc. were restricted to nati nal per capita availability. the nutrition satisfaction levels in per cent RDA by the model are 149-250 for protein , 51-106 for fat, 134-362 for iron an d143-1158 for Vitamin-A. Quantities of food legumes, cereals and leafy vegetables ranged from 289-601, 3000-3700 and 360-1200 g/day respectively for a reference family of five hard working rural poor. Daily food resources cost ranged from US$ 0.6 to 1.0 for the family. Amongst food legumes, soybean based diet combinations provide maximum nutritional benefits at minimum cost indicating its suitability for wider adoption by hard working poor.

• Asian-Australasian Journal of Animal Sciences
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• 제14권8호
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• pp.1078-1084
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• 2001

Twelve growing male lambs ($10.05{\pm}0.41kg$, 5 months age) were assigned to three equal groups in a completely randomized design and fed respectively wheat straw (WS), ammoniated wheat straw (AWS) or urea supplemented wheat straw (USWS) along with concentrate mixtures of varying protein and energy contents to meet their requirements as per NRC (1985). Despite comparable nutrient intake and digestibility, the lambs fed A WS based diet digested lower (p<0.05) crude protein. The digestibility of NDF and hemicellulose were lower while the digestibility of cellulose was higher in lambs on AWS as compared to lambs on USWS based diet. The lambs of all the three groups were in positive and comparable N, Ca and P balance except higher Ca balance in lambs fed WS based diet. The body weight change, average daily gain and feed conversion efficiency were similar among the dietary groups. All the parameters of rumen fermentation pattern were comparable between lambs of AWS and USWS based diets except ammonia-N concentration that was higher in the latter however it was lower in WS fed group. Though, the feeding cost per unit gain was comparable in lambs fed all the three diets, the cost incurred towards roughage during 120 days of experimental feeding was significantly less in lambs fed AWS than UTWS. Thus, feeding of USWS can be practiced to minimize labour cost and environmental pollution involved in the process of urea treatment without affecting the performance of growing lambs.

• Asian-Australasian Journal of Animal Sciences
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• 제16권3호
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• pp.374-379
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• 2003

Four rumen fistulated Murrah buffaloes were used to study the effect of four diets differing in roughage to concentrate ratio on rumen biochemical changes, microbial enzyme profile and in sacco degradability of feed in a $4{\times}4$ Latin Square design. The animals were fed four diets consisting of 80:20, 70:30, 60:40 and 50:50 ratios of wheat straw and concentrate mixtures, respectively. Wheat straw and concentrate mixture were mixed with water (0.6 l/kg feed) and complete feed mixture was offered to the animals at 8:00 h and 16:00 h in two equal parts. The variation in pH of rumen liquor (difference of maximum and minimum during 0-8 h post feeding) increased with increasing level of concentrate mixture in the diet. There was no effect of diet composition on volatile fatty acids, total nitrogen and trichloro-acetic acid precipitable nitrogen in the rumen liquor, but ammonia nitrogen increased with increasing level of concentrate mixture in the ration. Major portions of all fibre degrading enzymes were present in the particulate material (PM) of the rumen contents, but protease was absent in PM fraction. The activities of micro-crystalline cellulase, acetyl esterase and protease increased with increase in the level of concentrate mixture, but the activities of other enzymes (carboxymethylcellulase, filter paper degrading activity, xylanase, $\beta$-glucosidase and $\beta$-xylosidase) were not affected. The in sacco degradability and effective degradability of feeds increased with increasing level of concentrate mixture in the ration.

• Advances in aircraft and spacecraft science
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• 제10권2호
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• pp.107-125
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• 2023

Drag reduction is significant research in aircraft design due to its effect on the cost of operation and carbon footprint reduction. Aircraft currently use conventional solid winglets to reduce the induced drag, adding extra structural weight. Fluidic on-demand winglets can effectively reduce drag for low-speed flight regimes without adding any extra weight. These utilize the spanwise airflow from the wingtips using hydraulic actuators to create jets that negate tip vortices. This study develops a computational model to investigate fluidic on-demand winglets. The well-validated computational model is applied to investigate the effect of injection velocity and angle on the aerodynamic coefficients of a rectangular wing. Further, the turbulence parameters such as turbulent kinetic energy (TKE) and turbulent dissipation rate are studied in detail at various velocity injections and at an angle of 30°. The results show that the increase in injection velocity shifted the vortex core away from the wing tip and the increase in injection angle shifted the vortex core in the vertical direction. Further, it was found that a 30° injection is efficient among all injection velocities and highly efficient at a velocity ratio of 3. This technology can be adopted in any aircraft, effectively working at various angles of attack. The culmination of this study is that the implementation of fluidic winglets leads to a significant reduction in drag at low speeds for low aspect ratio wings.

• Structural Engineering and Mechanics
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• 제64권1호
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• pp.11-21
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• 2017

It has been observed in the past that, the reinforced concrete (RC) bridge columns are very often subjected to torsional moment in addition to flexure and shear during seismic vibration. Ignoring torsion in the design can trigger unexpected shear failure of the columns (Farhey et al. 1993). Performance based seismic design is a popular design philosophy which calls for accurate prediction of the hysteresis behavior of structural elements to ensure safe and economical design under earthquake loading. However, very few investigations in the past focused on the development of analytical models to accurately predict the response of RC members under cyclic torsion. Previously developed hysteresis models are not readily applicable for torsional loading owing to significant pinching and stiffness degradation associated with torsion (Wang et al. 2014). The present study proposes an improved polygonal hysteresis model which can accurately predict the hysteretic behavior of RC circular and square columns under torsion. The primary curve is obtained from mechanics based softened truss model for torsion. The proposed model is validated with test data of two circular and two square columns. A good correlation is observed between the predicted and measured torque-twist behavior and dissipated energy.

• International Journal of Ocean System Engineering
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• 제1권3호
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• pp.120-135
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• 2011

This paper proposes a model based trajectory tracking control scheme for under-actuated underwater robotic vehicles. The difficulty in stabilizing a non-linear system using smooth static state feedback law means that the design of a feedback controller for an under-actuated system is somewhat challenging. A necessary condition for the asymptotic stability of an under-actuated vehicle about a single equilibrium is that its gravitational field has nonzero elements corresponding to non-actuated dynamics. To overcome this condition, we propose a continuous time-varying control law based on the direct estimation of vehicle dynamic variables such as inertia, damping and Coriolis & centripetal terms. This can work satisfactorily under commonly encountered uncertainties such as an ocean current and parameter variations. The proposed control law cancels the non-linearities in the vehicle dynamics by introducing non-linear elements in the input side. Knowledge of the bounds on uncertain terms is not required and it is conceptually simple and easy to implement. The controller parameter values are designed using the Taguchi robust design approach and the control law is verified analytically to be robust under uncertainties, including external disturbances and current. A comparison of the controller performance with that of a linear proportional-integral-derivative (PID) controller and sliding mode controller are also provided.

• Advances in Computational Design
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• 제6권1호
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• pp.55-75
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• 2021

The lightweight superstructure is beneficial for bridges in remote areas and emergency erection. In such weight-sensitive applications, the combination of fiber-reinforced polymer (FRP) as a material and box-beams as a structural system have enormous scope. This combination offers various advantages, but as a thin-walled structure, their designs are often governed by buckling criteria. FRP box-beams lose their stability either by flange or web buckling mode. In this paper, the web buckling behavior of simply supported FRP box-beam subjected to transverse load has been studied by modeling full box-beam to consider the effect of real state of stress (stress variation in length direction) and boundary conditions (rotational restraint at web-flange junction). A parametric study by varying the sectional geometry and fiber orientation is carried out by using ANSYS software. The accuracy of the FE models was ensured by verifying them against the available results provided in the literature. With the help of developed database the influential parameters (i.e., αs, βw, δw and γ) affecting the web bucklings are identified. Design trends have been developed which will be helpful to the designers in the preliminary stage. Finally, the importance of governing parameters and design trends are demonstrated through pedestrian bridge design.

• Ocean Systems Engineering
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• 제12권3호
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• pp.301-333
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• 2022

Herein, we report meaningful and selective review of the progress made on 'Vortex Induced Vibration (VIV)' and 'Vortex Induced Motion (VIM)' of 'Structures of Specific Shapes (SoSS)' subjected to steady uniform flow and of relevance to/in marine structures. Important and critical elements of the numerical methods, experimental methods, and physical ideas are listed and analysed critically and the limitations of the current state of art of VIV/VIM are discussed in-detail. Our focus and aim are to analyse the existing researches with respect to the application in analyses, design and production of marine structures and the reported reviews centre on these only. We identify the critical and important issues that exist in the current literature and utilise these issues to highlight the challenges that need to be tackled to design and develop new age marine structures that can exist and operate safely in the areas of dominance by the VIV/VIM. Finally, we also identify some areas for future scope of research on VIV/VIM.

• Structural Engineering and Mechanics
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• 제56권5호
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• pp.707-726
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• 2015

There is a growing trend of considering uncertainty in optimization process since last few decades. In this regard, Robust Design Optimization (RDO) scheme has gained increasing momentum because of its virtue of improving performance of structure by minimizing the variation of performance and ensuring necessary safety and feasibility of constraint under uncertainty. In the present study, RDO of reinforced concrete folded plate and shell structure has been carried out incorporating uncertainty in the relevant parameters by Monte Carlo Simulation. Folded plate and shell structures are among the new generation popular structures often used in aesthetically appealing constructions. However, RDO study of such important structures is observed to be scarce. The optimization problem is formulated as cost minimization problem subjected to the force and displacements constraints considering dead, live and wind load. Then, the RDO is framed by simultaneously optimizing the expected value and the variation of the performance function using weighted sum approach. The robustness in constraint is ensured by adding suitable penalty term and through a target reliability index. The RDO problem is solved by Sequential Quadratic Programming. Subsequently, the results of the RDO are compared with conventional deterministic design approach. The parametric study implies that robust designs can be achieved by sacrificing only small increment in initial cost, but at the same time, considerable quality and guarantee of the structural behaviour can be ensured by the RDO solutions.