Dynamical behavior of generalized thermoelastic diffusion with two relaxation times in frequency domain

Sharma, Nidhi,Kumar, Rajneesh,Ram, Paras Techno-Press 2008 Structural Engineering and Mechanics, An Int'l Jou Vol.28 No.1

A general solution to the field equations of homogeneous isotropic generalized thermoelastic diffusion with two relaxation times (Green and Lindsay theory) has been obtained using the Fourier transform. Assuming the disturbances to be harmonically time.dependent, the transformed solution is obtained in the frequency domain. The application of a time harmonic concentrated and distributed loads have been considered to show the utility of the solution obtained. The transformed components of displacement, stress, temperature distribution and chemical potential distribution are inverted numerically, using a numerical inversion technique. Effect of diffusion on the resulting expressions have been depicted graphically for Green and Lindsay (G-L) and coupled (C-T) theories of thermoelasticity.

Dynamical behavior of generalized thermoelastic diffusion with two relaxation times in frequency domain

Nidhi Sharma,Rajneesh Kumar,Paras Ram 국제구조공학회 2008 Structural Engineering and Mechanics, An Int'l Jou Vol.28 No.1

A general solution to the field equations of homogeneous isotropic generalized thermoelastic diffusion with two relaxation times (Green and Lindsay theory) has been obtained using the Fourier transform. Assuming the disturbances to be harmonically time.dependent, the transformed solution is obtained in the frequency domain. The application of a time harmonic concentrated and distributed loads have been considered to show the utility of the solution obtained. The transformed components of displacement, stress, temperature distribution and chemical potential distribution are inverted numerically, using a numerical inversion technique. Effect of diffusion on the resulting expressions have been depicted graphically for Green and Lindsay (G-L) and coupled (C-T) theories of thermoelasticity.

Rice Hoppers and Associated Virus Diseases in Nepal

Hira Kaji Manandhar,Prem Nidhi Sharma 한국응용곤충학회 2012 한국응용곤충학회 학술대회논문집 Vol.2012 No.10

Nepal is endowed with rich diversity in land races of rice and also some wild rice species. Some of them are known for their resistance to insect and diseases, including rice hoppers and viruses. Nepal has so far released 68 improved rice varieties for different domains. With the introduction of improved varieties incidences of insect and diseases increased. Leafhoppers and planthoppers are among the rice insects of economic importance in Nepal. Till a decade ago, rice gundhi bug used to be the most important insect of rice. Now, hoppers have become more important. Of leafhoppers, green leafhopper (Nephotettix nigropictus), white leafhoppers (Cofena spectra) and zig zag leafhopper (Resilia dorsalis) are the common ones. Of them, N. nigropictus was found to transmit rice dwarf phytoreovirus, and N. virescens to transmit rice tungro bacilliform badna virus and rice tungro spherical waikavirus in Nepal. Of planthoppers, brown planthopper (BPH) (Nilaparvata lugens) and white-backed planthopper (WbPH) (Sogatella furcifera) are the major ones. Isolated outbreaks of BPH have been recorded from 1977 to recent past years and of WbPH in 1982. However, no virus diseases associated with BPH and WBPH have been recorded in Nepal though some yellow syndrome in large areas has been reported from BPH occurring area (Chitwan) for the last couple of years. It is worth to note that IPM-FFS (farmers’ field school) approach was adopted in 1997 in rice after the outbreak of BPH in Chitwan district. Farmers are practicing wetting and drying of rice fields for the management of BPH. Other management practices recommended include use of biopesticides, predators, light traps, chemicals and resistant varieties. With the objective of monitoring rice planthoppers and associated rice viruses Nepal in 2011 joined “Collaboration network for the management of migratory rice planthoppers and associated virus diseases of rice in Asia” - a regional project of Asian Food and Agriculture Cooperation Initiatives (AFACI), Korea.

Prevalence and patterns of post-COVID-19 symptoms in recovered patients of Delhi, India: a population-based study

Nidhi Bhatnagar,Mongjam Meghachandra Singh,Hitakshi Sharma,Suruchi Mishra,Gurmeet Singh,Shivani Rao,Amod Borle,Tanu Anand,Naresh Kumar,Binita Goswami,Sarika Singh,Mahima Kapoor,Sumeet Singla,Bembem Kh 질병관리청 2024 Osong Public Health and Research Persptectives Vol.15 No.3

Objectives: Post-coronavirus disease 2019 (COVID-19) symptoms were widely reported.However, data on post-COVID-19 conditions following infection with the Omicron variant remained scarce. This prospective study was conducted to understand the prevalence, patterns, and duration of symptoms in patients who had recovered from COVID-19.Methods: A prospective study was conducted across 11 districts of Delhi, India, among individuals who had recovered from COVID-19. Study participants were enrolled, and then returned for post-recovery follow-up at 3 months and 6 months interval.Results: The mean age of study participants was 42.07 years, with a standard deviation of 14.89 years. The majority of the participants (79.7%) reported experiencing post-COVID-19 symptoms. The most common symptoms included joint pain (36.0%), persistent dry cough (35.7%), anxiety (28.4%), and shortness of breath (27.1%). Other symptoms were persistent fatigue (21.6%), persistent headache (20.0%), forgetfulness (19.7%), and limb weakness (18.6%). The longest duration of symptom was observed to be anxiety (138.75±54.14 days), followed by fatigue (137.57±48.33 days), shortness of breath (131.89±60.21 days), and joint pain/swelling (131.59±58.76 days). At the first follow-up visit, 2.2% of participants presented with abnormal electrocardiogram readings, but no abnormalities were noticed during the second follow-up. Additionally, 4.06% of participants exhibited abnormal chest X-ray findings at the first follow-up, which decreased to 2.16% by the second visit. Conclusion: The most frequently reported post-COVID-19 symptoms were joint pain, dry cough, anxiety and shortness of breath. These clinical symptoms persisted for up to 6 months, with evidence of multi-system involvement. Consequently, findings highlighted the need for long-term follow-up during the post-COVID-19 period.

Hydro-Priming Methods for Initiation of Metabolic Process and Synchronization of Germination in Mung Bean (Vigna Radiata L.) Seeds

Nidhi Shukla,Himani Kuntal,Asheesh Shanker,Satyendra Nath Sharma 한국작물학회 2018 Journal of crop science and biotechnology Vol.21 No.2

Seed priming is a commercially applied technique for improving seed vigor under variable field conditions. The present study was carried out to optimize the methods (direct: soaking in water 1:1 W/V and indirect: preconditioning under high RH ≥ 85%) and duration (hours)of hydro-priming, attempting to correlate the critical seed water content with priming-induced metabolic-restart in dry mungbean (Vigna radiataL.)seeds. Although the rate of water absorption and the amount of water absorbed was more by direct compared to the indirect imbibition method, the priming-induced germination responses were identical after 6hof priming treatment. The seed water content absorbed during this period was crucial for initiating the chain of biochemical events, required for early synchronized germination in primed seeds which was evident by improved membrane permeability, high activity of catalase and superoxide dismutase, and more integrated chloroplast and mitochondria in primed seeds. We demonstrate that the critical water content, required for priming-induced benefits for germination vigor, is a relative unit with respect to the duration of priming and the rate of water absorption. Seed priming is a co-ordinately regulated mechanism for controlling germination capacity of seeds by modifying the permeability characteristics of biological membranes and enzyme activity. This study helps to enhance our understanding on the potential of seed priming for synchronized germination and early seedling establishment in the field and beneficial for the resource poor farming community for better return of their limited financial/farm resources under variable environmental/field conditions.

Representation of fundamental solution and vibration of waves in photothermoelastic under MGTE model

Rajneesh Kumar,Nidhi Sharma,Supriya Chopra,Anil K. Vashishth Techno-Press 2023 Ocean systems engineering Vol.13 No.2

In this paper, Moore-Gibson-Thompson theory of thermoelasticity is considered to investigate the fundamental solution and vibration of plane wave in an isotropic photothermoelastic solid. The governing equations are made dimensionless for further investigation. The dimensionless equations are expressed in terms of elementary functions by assuming time harmonic variation of the field variables (displacement, temperature distribution and carrier density distribution). Fundamental solutions are constructed for the system of equations for steady oscillation. Also some preliminary properties of the solution are explored. In the second part, the vibration of plane waves are examined by expressing the governing equation for two dimensional case. It is found that for the non-trivial solution of the equation yield that there exist three longitudinal waves which advance with the distinct speed, and one transverse wave which is free from thermal and carrier density response. The impact of various models (i)Moore-Gibson-Thomson thermoelastic (MGTE)(2019), (ii) Lord and Shulman's (LS)(1967) , (iii) Green and Naghdi type-II(GN-II)(1993) and (iv) Green and Naghdi type-III(GN-III)(1992) on the attributes of waves i.e., phase velocity, attenuation coefficient, specific loss and penetration depth are elaborated by plotting various figures of physical quantities. Various particular cases of interest are also deduced from the present investigations. The results obtained can be used to delineate various semiconductor elements during the coupled thermal, plasma and elastic wave and also find the application in the material and engineering sciences.

Effects of stiffness on reflection and transmission of micropolar thermoelastic waves at the interface between an elastic and micropolar generalized thermoelastic solid

Kumar, Rajneesh,Sharma, Nidhi,Ram, Paras Techno-Press 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.31 No.2

The reflection and transmission of micropolar thermoelastic plane waves at the interface between an elastic solid and micropolar generalized thermoelastic solid is discussed. The interface boundary conditions obtained contain interface stiffness (normal stiffness and transverse stiffness). The expressions for the reflection and transmission coefficients which are the ratios of the amplitudes of reflected and transmitted waves to the amplitude of incident waves are obtained for normal force stiffness, transverse force stiffness and welded contact. Numerical calculations have been performed for amplitude ratios of various reflected and transmitted waves. The variations of amplitude ratios with angle of incident wave have been depicted graphically. It is found that the amplitude ratios of reflected and transmitted waves are affected by the stiffness, micropolarity and thermal distribution of the media.

Photothermoelastic interactions under Moore-Gibson-Thompson thermoelasticity

Kumar, Rajneesh,Sharma, Nidhi,Chopra, Supriya Techno-Press 2022 Coupled systems mechanics Vol.11 No.5

In the present work, a new photothermoelastic model based on Moore-Gibson-Thompson theory has been constructed. The governing equationsfor orthotropic photothermoelastic plate are simplified for two-dimension model. Laplace and Fourier transforms are employed after converting the system of equations into dimensionless form. The problem is examined due to various specified sources. Moving normal force, ramp type thermal source and carrier density periodic loading are taken to explore the application of the assumed model. Various field quantities like displacements, stresses, temperature distribution and carrier density distribution are obtained in the transformed domain. The problem is validated by numerical computation for a given material and numerical obtained results are depicted in form of graphs to show the impact of varioustheories of thermoelasticity along with impact of moving velocity, ramp type and periodic loading parameters. Some special cases are also explored. The results obtained in this paper can be used to design various semiconductor elements during the coupled thermal, plasma and elastic wave and otherfieldsin thematerialscience, physical engineering.

Cervical Cancer Screening: Knowledge, Attitude and Practices among Nursing Staff in a Tertiary Level Teaching Institution of Rural India

Shekhar, Shashank,Sharma, Chanderdeep,Thakur, Sita,Raina, Nidhi Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.6

Background: Assessment of the nursing staff knowledge, attitude and practices about cervical cancer screening in a tertiary care teaching institute of rural India. Materials and Methods: A cross sectional, descriptive, interview-based survey was conducted with a pretested questionnaire among 262 staff nurses of a tertiary care teaching and research institute. Results: In this study 77% respondents knew that Pap smear is used for detection of cervical cancer, but less than half knew that Pap smear can detect even precancerous lesions of cervix. Only 23.4% knew human papilloma virus infection as a risk factor. Only 26.7% of the respondents were judged as having adequate knowledge based on scores allotted for questions evaluating knowledge about cervical cancer and screening. Only 17 (7%) of the staff nurses had themselves been screened by Pap smear, while 85% had never taken a Pap smear of a patient. Adequate knowledge of cervical cancer and screening, higher parity and age >30 years were significantly associated with self screening for cervical cancer. Most nurese held a view that Pap test is a doctor procedure, and nearly 90% of nurses had never referred a patient for Pap testing. Conclusions: The majority of nursing staff in rural India may have inadequate knowledge about cervical cancer screening, and their attitude and practices towards cervical cancer screening could not be termed positive.

ANN Based Direct Modeling of Permanent Magnet DC Tachogenerator Sensor

Ashu Gautam,Nidhi Sharma 보안공학연구지원센터 2015 International Journal of Hybrid Information Techno Vol.8 No.10

Non-linearity coupled by all of the sensors and transducers gives set to either difficulties for direct digital readout, on-chip interface, testing, calibration and control. Also, the performance of a transducer is affected adversely by variations in working environments over them. Under the sovereignty of ANN based transducer modeling, the use of single layer ANN has been proposed in two separate studies with quite affluent results. The first existing model is based on the architecture of an adaptive linear (ADALINE) network trained with Widrow-Hoff’s learning algorithm. The other is based on the concept of Functional Link Artificial Neural Network (FLANN) designed on the architecture of a single layer linear ANN trained with Gradient-descent with momentum based learning algorithm. To have an optimal solution, it is proposed to amalgamate the direct model of the transducers using the concept of a Polynomial-ANN trained with BFGS Quasi-Newton Learning algorithm. The proposed Polynomial-ANN oriented transducer model is implemented based on the topology of a single-layer feed-forward back-propagation network. The proposed transducer modeling technique provides an extremely fast convergence speed with increased accuracy for the assessment of static input-output characteristics of the transducers and also for the solution of linearizing the non-linear transducers.