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Context. Soil-tool interaction modelling and optimisation reduce manufacturing costs and energy requirements for precision tillage equipment design. Diverse tillage tools have been designed to reduce draft requirements and desirable soil disturbance, but this is not fully understood. Aims. The current study investigated the effects of tool width, cone index, depth, and forward speed on draft with corresponding rupture width in order to develop response surface methodology (RSM) and artificial neural network (ANN) models and compared them to other models in order to predict draft and rupture width. Methods. Experiments were carried out in a soil bin with a vertisol, and rupture width was measured using an image processing technique. Key results. Using RSM, the optimum values for minimum draft with maximum rupture width within a range of independent variables were found to be l00 mm tool width, 600 kPa cone index, 141.63 mm tillage depth, and 3 km/h forward speed. For predicting the draft, the coefficients of determination ([R.sup.2]) for ANN and RSM models were 0.997 and 0.987, respectively; for rupture width prediction, [R.sup.2] were 0.921 and 0.976. Conclusions. Developed ANN and RSM models of draft and rupture width were better than other analytical or numerical models, and both models' predictions were in good agreement with experiment values within the range of [+ or -] 5% uncertainty. Implications. The developed models can be used to predict the draft and soil disturbance requirements of tillage tools and design precision tillage tools. Keywords: artificial neural network, cone index, draft, image processing, modelling, response surface methodology, rupture width, vertisols., Introduction Tillage operations are an unavoidable step in agricultural production systems, and consume energy and time. For a proper tillage operation, extensive knowledge of soil characteristics before, during, and after [...]

Modelling and optimizing soil-tool interaction parameters for tillage operations is crucial for developing efficient and precise tools. This study focused on a specific draft of sweep tools in the soil bin filled with vertisol, considering factors such as tool geometry, cone index, working depth and operational speed. Data analysis showed that the range of specific draft values, from 9.51 to 38.95 kN/m2. Machine learning models, including artificial neural network (ANN), support vector machine (SVM), bagged trees (BT) and boosted trees (BoT), were developed using experimental data to predict the specific draft of sweep tools with hyperparameter configuration. The developed machine learning models have also been compared with the predictive multiple linear regression (MLR) model, and it was found that the predictive performance of the machine learning models was better than the MLR model during training and testing. The fine-tuned ANN model achieved impressive statistical performance with the lowest mean absolute error (MAE) of 0.489 kN/m2, root mean square error (RMSE) of 0.619 kN/m2, standard error of prediction (SEP) of 3.462% and highest coefficient of determination (R2) of .99 during testing. R2 values for BT, BoT, SVM and MLR models were .97, .96, .94 and .83, respectively, for specific draft predictions. The findings from this study have practical implications for optimizing sweep tool design and improving tillage operation. Manufacturers and farmers can benefit from predictive modelling using machine learning to design and select appropriate tillage tools for specific soil conditions. This approach can lead to improved soil health, increased yields and reduced costs. [ABSTRACT FROM AUTHOR]

In this work, we consider a hybrid aerial full-duplex (FD) relaying protocol consisting of a reconfigurable intelligent surface (RIS) mounted over an FD unmanned aerial vehicle (UAV) relay operating in the decode and forward mode to assist the information transfer between the base station and multiple users. For better spectral efficiency, we investigate the use of non-orthogonal multiple access (NOMA) in such networks and focus on both the performance analysis and design optimization of the considered RIS-NOMA network under imperfect channel state information (CSI) and successive interference cancellation (SIC) at each user, and residual-self interference (RSI) at UAV. We first formulate the sum rate maximization problem and adopt the block coordinate descent method to deal with the non-convex nature of the problem. Thereafter, we propose an algorithm based on the Riemannian conjugate gradient method to get the optimal phase shifts at the RIS, an iterative algorithm to obtain the optimal UAV/RIS position and the exhaustive method to obtain the optimum power allocation coefficients. Next, with obtained optimal position, phase shift and power coefficients, we further analyze the performance of the network and derive the closed-form expressions of outage probability, achievable throughput and ergodic capacity. We present Monte Carlo simulation-based results to validate the accuracy of the proposed algorithms and derived expressions and demonstrate the superiority of NOMA over OMA. [ABSTRACT FROM AUTHOR]

Owing to the factors such as controllable mobility, ready-to-use technology, low cost, easy implementation, and so on, unmanned aerial vehicle (UAV) possesses tremendous potential to be one of the primary candidates for next-generation (6G) wireless networks. This paper presents a UAV-assisted multiuser communication network where a multiple antenna UAV base station (BS) serves multiple single antenna ground users (GUs). UAV-BS uses a laser source-based charging mechanism to fulfill its power requirement and applies simultaneous wireless information and power transfer (SWIPT) in the downlink in order to provide desired power to energy-constrained GUs. Also, a clustering-based hybrid multiple access technique is used that combines both orthogonal multiple access (OMA) and non-orthogonal multiple access (NOMA) signaling to transmit the information to all GUs, simultaneously. Due to the involved analytical complexity corresponding to the multiple antennas and users, we use a hybrid beamforming method for efficient communication. Next, we analyze the performance of the proposed framework in terms of user outage probabilities, their respective throughput, and average power harvested considering non-linear energy harvesting and derive expressions of these performance metrics. Moreover, we formulate an optimization problem where the throughput of one GU is maximized by optimally choosing the power allocation parameter while ensuring the desired target throughput at other GU in each cluster. We also illustrate how crucial is the optimal selection of the target rates to maximize the network performance. Simulation results are provided to validate the accuracy of derived expressions and to highlight the dominance of hybrid beamforming and hybrid NOMA compared to conventional methods on the performance of the considered network. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of a new framework for low-outage downlink non-orthogonal multiple access (NOMA) using a coordinated direct and relay transmission (CDRT) scheme with direct links to both the near-user (NU) and the far-user (FU). Both amplify-and-forward and decode-and-forward relays are considered. In this framework, the NU combines the signals from base-station and relay at each stage of the successive interference cancellation (SIC) to attain good outage performance. For both NU and FU, the expressions for outage probability and throughput are derived in closed form. We also derive the high-SNR expressions for the outage probability to demonstrate that with the proposed framework, both users harness a diversity of two without feedback bits (this is the only framework to achieve this). We demonstrate that the choice of power allocation coefficient and target symbol rates is crucial to maximizing the NU throughput while ensuring a desired target FU throughput. We demonstrate that CDRT with the proposed framework outperforms known schemes in terms of outage probability, sum throughput, and energy efficiency. Moreover, we also show that optimal rate selection is important to maximize the energy efficiency. Monte Carlo simulations validate the accuracy of the derived analytical expressions. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of a non-orthogonal multiple access (NOMA) network with simultaneous wireless information, and power transfer (SWIPT) based battery-assisted energy harvesting (EH) full-duplex relay (FDR). In each signalling interval, the base-station communicates directly to a near user (NU), and through an EH FDR to a far user (FU). Considering the power-splitting (PS) protocol with a non-linear EH model, we derive closed-form expressions for the NU, and FU outage probabilities. We also demonstrate how the battery energy, and PS parameter can be chosen to maximize the FU throughput while ensuring a desired NU throughput when there is imperfect interference cancellation at the NU. Computer simulation results validate the accuracy of the derived expressions, and demonstrate that augmenting the harvested energy with a small quantum of the relay's battery energy can considerably improve the FU performance. [ABSTRACT FROM AUTHOR]

Earth air tunnel heat exchanger (EATHE) is a promising passive technique to provide thermal comfort condition in buildings. EATHE system uses undisturbed temperature of the ground for heating/cooling of air. Despite the several advantages, this technique has not become much popular owing to its high capital cost (mainly pipe cost and trench excavation cost) and large land area requirements. The primary objective of this study is to present a comprehensive review of different EATHE pipe layouts, pipe properties and positioning of the pipe with their advantages and limitations. It is observed that the ring pipe layout is the most cost-effective pipe-layout for small size EATHE system because it saves excavation cost by using a trench of the existing foundation of the building. However, Grid pipe-layout is an ideal layout for a large size EATHE system. Multi-layer pipe layouts should be used to reduce the land area requirement significantly. Moreover, EATHE system can be installed beneath the building (under building foot-print) to eliminate extra land area requirement for the installation of EATHE system. This review article shows that the Initial capital cost and land area requirement for the EATHE system can be substantially reduced by using appropriate pipe layout. It can be concluded that if EATHE system is installed with proper design strategies, it will be a clean and cost-effective method for building heating/cooling with significant power savings. [ABSTRACT FROM AUTHOR]

A field experiment was conducted in spit plot design with three replication to "to study different rice establishment methods on growth, yield and different varieties" was conducted at Agronomy farm, College of Agriculture, Dapoli, Distt. Ratnagiri (M.S.) during kharif season of 2014 on was sandy clay loam in texture, moderately acidic in pH (5.63), medium in organic carbon content (0.82 %), electrical conductivity (Ec) 0.035 dSm-1 , medium in available nitrogen (284.82 kg/ha), low in available phosphorus (14.63 kg/ha) and high in available potassium (248.45 kg/ha). The highest plant height (71.09 cm), effective tillers (360.58 m2), length of panicle (21.07 cm), test weight (22.24 g), straw yield (47.42 q ha-1), weight of per panicle (2.15 g), number of filled grains per panicle (97.08) and B:C ratio (1:2.23) were recorded in line transplanting technique. Based on the results obtained, it can be concluded that in areas where labour is available and cheap, transplanting as per as recommended (21 days old age seedling) is a better establishment methods of rice because it produces more yield and gross monetary economic return than other methods. [ABSTRACT FROM AUTHOR]

Background/aim: India has 63 million diabetic people and the overall prevalence of diabetes in this country is 8.37%. Lifestyle modification by education is the most cost-effective strategy to have better metabolic control. The aim of this study was to investigate the effects of a self-management educational program on control of type 2 diabetes. Materials and methods: It was a randomized controlled interventional study conducted among 306 patients with type 2 diabetes mellitus attending the Diabetic Clinic at G.T.B. Hospital, Delhi, from March 2010 to May 2013. The intervention was in the form of group education based on a self-management program, which was earlier developed in the pilot study. Results: The baseline characteristics were comparable in the two groups. After 6 months, there was a significant improvement in the HbA1c levels (P = 0.0001), physical activity level (P = 0.001), and BMI (P = 0.001) in the study group as compared to the control group and this difference persisted even when analysis was done using generalized estimation equations. Conclusion: The findings of this study proved that a self-management educational program is an essential component in the management of diabetes and provided concrete evidence that this is an effective instrument in the control of body weight, blood pressure, and glycated Hb levels in type 2 diabetes. [ABSTRACT FROM AUTHOR]

Costing is important for manufacturing industries. Large methods of costing have evolved over time. Recently, the time-driven activity- based costing (TDABC) system has gained importance and application. This article describes the procedure that allows companies to implement TDABC using the Maynard operation sequence technique (MOST) for improving productivity and profitability. Two parameters are required for TDABC: (1) the unit cost of supplying capacity, and (2) the time required to perform a transaction or an activity. MOST is employed to estimate the time required for each activity. Based on this, time equations are formulated and the practical capacity of activities is determined. The procedure is explained with the help of a case study from a manufacturing industry. The results of the case study are discussed from the perspective of the overall company and also at the product level. This approach provides the capacity analysis and the cost analysis together with its hierarchical decomposition. This paper also discusses the different information obtained from TDABC, and its usefulness for managers and decision-makers.

Background and Aim: The risk of acquiring hepatitis B virus (HBV) infection through exposure to blood or its products is highest amongst health care workers (HCWs). Despite potential risks, a proportion of HCWs never get vaccinated. India is second to China in the numbers of people with chronic HBV. This study aimed to investigate the vaccination practices and the prevalence of HBV infection in HCWs in India. Methods: A total of 2162 HCWs were screened for the presence of serological markers of HBV and hepatitis C virus (HCV). Occult HBV infection was tested by detection of HBV-DNA for surface and core regions by nested polymerase chain reaction in HBsAg-negative and IgG anti-hepatitis core antigen–positive subjects. Results: Only 1198 (55.4%) of the 2162 HCWs screened had been vaccinated; and 964 (44.6%) were not vaccination-status conscious; of these HCWs, 600 (27.7%) had never been vaccinated and 364 (16.4%) were unaware of their vaccination status. Protective (> 10 IU/mL) anti-hepatitis B surface (anti-HBs) antigen titers were seen in only 61.7%. The anti-HBs titers were found to be lower with the passage of time; the median anti-HBs titers in subjects who were vaccinated > 10 years ago were significantly lower than those who had been vaccinated < 5 years ago ( P < 0.001). One percent of HCWs were HBsAg-positive, and 24.7% of 700 HCWs screened had past exposure (IgG-anti-HBc-positive). Occult HBV was detected in 5% of 120 positive subjects with past exposure; all had anti-HBs titers > 10 IU/mL. Conclusions: Even today, 28% HCWs in India are unvaccinated and 17% are unaware of their vaccination status. This data suggests that use of hepatitis B immune globulin be mandatory in needle-pricked HCWs in India, and that implementation of awareness strategies is urgent. Since the anti-HBs titers decline in a fair proportion, there is justification for giving a booster dose of vaccine 10 years after primary vaccination to HCWs in India. [ABSTRACT FROM AUTHOR]

• Development of a laboratory scale experimental set up with slinky-coil pipe layout. • Use of sand–bentonite mixture as backfilling material for GAHE system. • Required length of the trench is reduced by using slinky-coil pipe layout. • Substantial saving in terms of excavation cost and piping cost. The ground-air heat exchanger (GAHE) is the promising passive technique for building heating/cooling, but due to its high installation cost (mainly pipe cost and excavation cost), it could not become popular. The required length of pipe can be reduced by using thermally enhanced backfilling material (BFM), while, the length of the trench can be reduced by using slinky-coil pipe layout. In the present study, an experimental laboratory setup of GAHE system has been developed with a slinky-coil pipe layout and sand-bentonite as BFM. For this, a flexible PVC pipe of 75 mm diameter and 30 m length, has been arranged in slinky-coil pattern and installed horizontally in a soil box of 10.2 m length. For the study, variation in soil temperature (23 °C–27 °C), inlet air temperature (38 °C–46 °C), air flow velocity (5 m/s–20 m/s) and soil conditions (dry and wet), have been considered. Study reveals that a drop-in air temperature as high as 18.7 °C at 30 m pipe length (trench length of 10.2 m) can be achieved with soil at a temperature of 27 °C and inlet air temperature of 46 °C. The study also revealed that the pipe length could be reduced by 20% with wet sand-bentonite as compared to dry sand-bentonite. [ABSTRACT FROM AUTHOR]

Abstract: The non-response to hepatitis B vaccine in health care workers (HCWs) is reported to vary between 5 and 40%. The underlying cellular and molecular events for unresponsiveness to HBV vaccine have not yet been characterized at any great extent. In the current study, we examined the CD150 surface expression levels and its association with polyclonally activated and HBV specific stimulated cellular proliferations in responders and non-responders. CD150 was identified as upregulated expression marker with suppressive regulatory cell function on all activated T cells by gene chip analysis. We found the overall weak cellular proliferation in response to specific and non-specific agents in non-responders. This is significantly associated with enhanced surface expression of CD150 in the non-responders. A strong expression of CD150 with weak cellular proliferation could be used as a predictive marker for non-responsiveness. [Copyright &y& Elsevier]

Hepatitis B virus is the world's most common blood borne viral infection. Occupational risk of Hepatitis B infection is well known in medical and dental workers especially during the professional training period. The present study was conducted among medical students of a Medical College in Delhi to assess their knowledge regarding Hepatitis B. A questionnaire was administered to the first, third and final year medical students regarding Hepatitis B vaccine, disease, and mode of spread, sequel and prevention. The knowledge regarding all aspects was maximum amongst the final year students as compared to first and third years. Knowledge regarding the booster dose of vaccine, transmission through formites, universal precautions for prevention was not good. There is need for strengthening in these areas and training in these should be started at the earliest.