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| 1 | Optimal Control of Nonlinear Inverted Pendulum System Using PID Controller and LQR: Performance Analysis Without and With Disturbance Input显示文摘Linear quadratic regulator(LQR) and proportional-integral-derivative(PID) control methods, which are generally used for control of linear dynamical systems, are used in this paper to control the nonlinear dynamical system. LQR is one of the optimal control techniques, which takes into account the states of the dynamical system and control input to make the optimal control decisions.The nonlinear system states are fed to LQR which is designed using a linear state-space model. This is simple as well as robust. The inverted pendulum, a highly nonlinear unstable system, is used as a benchmark for implementing the control methods. Here the control objective is to control the system such that the cart reaches a desired position and the inverted pendulum stabilizes in the upright position. In this paper, the modeling and simulation for optimal control design of nonlinear inverted pendulum-cart dynamic system using PID controller and LQR have been presented for both cases of without and with disturbance input. The Matlab-Simulink models have been developed for simulation and performance analysis of the control schemes. The simulation results justify the comparative advantage of LQR control method. | Lal Bahadur Prasad Barjeev Tyagi Hari Om Gupta | 2014 | International Journal of Automation and computing2014，11，6： | 32 |
| 2 | Serum uric acid level in newly diagnosed essential hypertension in a Nepalese population:A hospital based cross sectional study显示文摘Objective:To develop the missing link between hyperuricemia and hypertension.Methods:The study was conducted in Department of Biochemistry in collaboration with Nephrology Unit of Internal Medicine Department.Hypertension was defined according to blood pressure readings by definitions of the Seventh Report of the Joint National Committee.Totally 205newly diagnosed and untreated essential hypertensive cases and age-sex matched nonnotensive controls were enrolled in the study.The potential confounding factors of hyperuricemia and hypertension in both cases and controls were controlled.Uric acid levels in all participants were analyzed.Results:Renal function between newly diagnosed hypertensive cases and nonnotensive healthy controls were adjusted.The mean serum uric acid observed in newly diagnosed hypertensive cases and in nonnotensive healthy controls were(290.05±87.03)μmol/L and(245.24±09.38)μmol/L respectively.A total of 59(28.8%)participants of cases and 28(13.7%)participants of controls had hyperuricemia(odds ratio 2.555(95%CI:1.549-4.213),P<0.00l).Conclusions:The mean serum uric acid leveb and number of hyperuricemic subjects were found to be significantly higher in cases when compared to controls. | Bibek Poudel Binod Kumar Yadav Arun Kumar Bharat Jha Kanak Bahadur Raut | 2014 | Asian Pacific Journal of Tropical Biomedicine2014，4，1： | 10 |
| 3 | Integrated Bi2O3 nanostructure modified with Au nanoparticles for enhanced photocatalytic activity under visible light irradiation显示文摘An integrated Bi_2O_3(i-Bi_2O_3) nanostructure with a particle size 10 nm inducing agglomerated structure were synthesized by dissolving bismuth nitrate pentahydrate in diethylene glycol at 180 ℃ with post heat treatment.The prepared i-Bi_2O_3 nanostructures were employed for the construction of Au/i-Bi_2O_3 composite system and characterized by X-ray diffraction pattern,UV-visible diffuse reflectance spectroscopy(DRS),and transmission electron microscopy,X-ray photoemission spectroscopy(XPS) and Energy dispersive X-ray spectroscopy(EDS).The i-Bi_2O_3 nanostructure and Au/i-Bi_2O_3 composite system were found to exhibit high photocatalytic activity than commercial Bi_2O_3 in decomposing salicylic acid under visible light irradiation.The high catalytic activity of i-Bi_2O_3 nanostructure was deduced to be caused by charge separation facilitated by electron hopping between the particles within the integrated structure and space-charge separation between i-Bi_2O_3 and Au.The charge separation behavior in i-Bi_2O_3 nanostructure was further bolstered by comparing the measured.OH radical produced in the solution with i-Bi_2O_3 nanostructure,commercial Bi_2O_3 and Au/i-Bi_2O_3 composite which readily react with 1,4-terephthalic acid(TA) inducing 2-hydroxy terephthalic acid(TAOH) that shows unique fluorescence peak at 426 nm.The space-charge separation between i-Bi_2O_3 and An was confirmed by measuring the electron spin resonance(ESR) spectra. | Hankwon Lim Sher Bahadur Rawal | 2017 | Progress in Natural Science:Materials International2017，27，3： | 5 |
| 4 | Improved photocatalytic degradation of organic dye using Ag3PO4/MoS2 nanocomposite显示文摘 | Madhulika SHARMA Pranab Kishore MOHAPATRA Dhirendra BAHADUR | 2017 | Frontiers of Materials Science2017，11，4： | 4 |
| 5 | Effects of Annealing Temperature on the Structural,Optical,and Electrical Properties of ZnO Thin Films Grown on n-Si<100>Substrates by the Sol–Gel Spin Coating Method显示文摘The effects of annealing temperature on the sol–gel-derived ZnO thin films deposited on n-Sh100 i substrates by sol–gel spin coating method have been studied in this paper.The structural,optical,and electrical properties of ZnO thin films annealed at 450,550,and 650 °C in the Ar gas atmosphere have been investigated in a systematic way.The XRD analysis shows a polycrystalline nature of the films at all three annealing temperatures.Further,the crystallite size is observed to be increased with the annealing temperature,whereas the positions of various peaks in the XRD spectra are found to be red-shifted with the temperature.The surface morphology studied through the scanning electron microscopy measurements shows a uniform distribution of ZnO nanoparticles over the entire Si substrates of enhanced grain sizes with the annealing temperature.Optical properties investigated by photoluminescence spectroscopy shows an optical band gap varying in the range of 3.28–3.15 eV as annealing temperature is increased from 450 to 650 °C,respectively.The fourpoint probe measurement shows a decrease in resistivity from 2:1 10 2to 8:1 10 4X cm with the increased temperature from 450 to 650 °C.The study could be useful for studying the sol–gel-derived ZnO thin film-based devices for various electronic,optoelectronic,and gas sensing applications. | Aniruddh Bahadur Yadav Amritanshu Pandey S.Jit | 2014 | Acta Metallurgica Sinica(English Letters)2014，27，4： | 4 |
| 6 | Factors Affecting Adoption of Improved Rice Varieties among Rural Farm Households in Central Nepal显示文摘The use of improved high yielding crop varieties is an important avenue for reducing hunger and food insecurity in developing countries. Using cross-sectional data obtained from a survey conducted during 2013 crop season, we performed a probit model(plot-level analysis) to determine the probability of adopting new improved rice varieties(NIRVs) by smallholder farmers particularly from two main agro-ecological regions(hills and tropical plain terai regions) of Central Nepal. The results revealed that education, extension services and seed access play significant roles in adoption decisions.Additionally, farm and field characteristic variables such as farm size, endowment of favorable land type(e.g. lowlands), and animal power(e.g. oxen) are the key factors influencing the probability of adopting NIRVs. The results showed that technology specific variables(e.g. yield potential and acceptability) are significant for explaining adoption behavior, implying that it is important to take farmers' preferences to varietal characteristics into consideration in the design of a research and development program. Given the significant role played by extension and access related variables, increased emphasis on information dissemination, field demonstration, and farmers' participatory research and training programs to popularize new rice varieties and enhance their adoption rate are required. This also suggests that policy intervention should be made on improving the educational status of farming households, and developing programs on varietal package of rice seed which offer farmers a variety of choices among the appropriate pools of germplasm. Such programs ultimately help farmers develop more profit-oriented behavior which are necessary to enhance adoption rate, production and food security in the long run. | Raju GHIMIRE HUANG Wen-chi Rudra Bahadur SHRESTHA | 2015 | Rice science2015，22，1： | 4 |
| 7 | Amount and temperature effects responsible for precipitation isotope variation in the southern slope of Himalayas显示文摘Seasonal variation of stable isotopes in precipitation of Kathmandu Valley on the southern slope of Himalaya was carried out to understand the controlling mechanism of amount and temperature effect on the basis of one year stable isotope data from 2010 to 2011. Highly depleted isotope values in major rainy period are obtained just after the onset of precipitation in summer, which accounts for 'amount effect' due to saturation isotopic compositions in high moisture condition, whereas, the higher values in winter are indicative to regional vapors (temperature effect) recycling of various sources. An abrupt depletion of isotope values in mid-June, indicates the onset date of monsoon precipitation, by the replacement of winter air mass with southern monsoon. Thus, precipitation isotopes are a tool revealing the onset date of summer monsoon and temporal features of variability, in local and regional monsoons precipitations. A comparison of long term monthly values of δ 18 O, temperature, and precipitation with GNIP δ 18 O data shows the temporal variations of stable isotopes are mostly controlled by amount and temperature effects. During summer monsoon, the amount effects are stronger for high values of precipitation (R=0.7) and altitude effect appears for low moisture in late rainy season, thus from December to June (winter to pre-monsoon) the controlling features of isotopes remains under the temperature effect. A temporal rate of temperature effect is derived as 0.04‰ per year which indicates a dry signal of atmospheric condition and a temperature relation δ 18 O=(0.371±0.08)T+(0.156±0.05) is obtained from this analysis. The meteoric water lines of Kathmandu before and after monsoon onset of 2011, are found as δD=(4.36±0.3)δ 18 O+(15.66±1.2) and δD=(6.91±0.2)δ 18 O (7.92±2.26) from lab samples result, and δD=9.2δ 18 O+11.725 and δD=8.53δ 18 O+16.65 from GNIP data, which lacks the consistency both for slopes and intercepts values for the study period. The mean lapse rate values of δ 18 O and δD from GNIP data are obtained as 0.002‰/m and 0.015 ‰/m, which indicate the altitudinal effects in regional precipitation of the southern slope of Himalayas. This study estimates new stable isotopes data in recent precipitation using simple methodology which can be important for regional precipitation monitoring systems, environmental change and paleo-climatic studies. | Tek Bahadur Chhetri TanDong Yao LiDe Tian XinPing Zhang | 2013 | Research in Cold and Arid Regions2013，5，2： | 3 |
| 8 | Application of soft computing techniques for shallow foundation reliability in geotechnical engineering显示文摘This research focuses on the application of three soft computing techniques including Minimax Probability Machine Regression(MPMR),Particle Swarm Optimization based Artificial Neural Network(ANN-PSO)and Particle Swarm Optimization based Adaptive Network Fuzzy Inference System(ANFIS-PSO)to study the shallow foundation reliability based on settlement criteria.Soil is a heterogeneous medium and the involvement of its attributes for geotechnical behaviour in soil-foundation system makes the prediction of settlement of shallow a complex engineering problem.This study explores the feasibility of soft computing techniques against the deterministic approach.The settlement of shallow foundation depends on the parametersγ(unit weight),e0(void ratio)and CC(compression index).These soil parameters are taken as input variables while the settlement of shallow foundation as output.To assess the performance of models,different performance indices i.e.RMSE,VAF,R^2,Bias Factor,MAPE,LMI,U(95),RSR,NS,RPD,etc.were used.From the analysis of results,it was found that MPMR model outperformed PSO-ANFIS and PSO-ANN.Therefore,MPMR can be used as a reliable soft computing technique for non-linear problems for settlement of shallow foundations on soils. | Rahul Ray Deepak Kumar Pijush Samui Lal Bahadur Roy A.T.C.Goh Wengang Zhang | 2021 | Geoscience Frontiers2021，12，1： | 3 |
| 9 | The wear of filled polytetrafluoroethylene 显示文摘 | Bahadur S Tabor D | 1984 | Wear1984，94，1： | 2 |
| 10 | Hydrochemistry and sediment characteristics of polar periglacial lacustrine environments on Fisher Island and Broknes Peninsula,East Antarctica显示文摘Fisher Island and Broknes Peninsula in the Larsemann Hills constitute part of a polar lowland periglacial environment between marine and glacial ecosystems.The landscape is characterized by gently rolling hills and broad valleys interspersed with lakes formed in glacially scoured basins.We analyzed the physicochemical parameters and the ionic constituents of water samples from 10 lakes in each of these two locations.Our results showed considerable differences between the two regions and demonstrated the influence of lithology and processes including weathering,evaporation,and atmospheric precipitation.All major cations and anions in the lake waters showed positive correlations indicating balanced ionic concentrations.Unconsolidated sediments were sparsely distributed and scattered over glacial deposits,valley fills,and occasional moraine ridges.The type and rate of sedimentation was mainly controlled by surface run-off and aeolian influx.The sediment samples from lake beds and the catchment area on Fisher Island were immature and poorly to very poorly sorted,consisting of gravelly sand with negligible silt and finer fractions.Sediments had a polymodal grain size distribution with the two major populations lying between-2 and-1 phi and between 0 and 1.5 phi.The sediments were lithic arenite to arkosic in composition and the microtextures imprinted over quartz grains were dominated by mechanical textures resulting from several stages of glacial crushing and grinding.The presence of deep dissolution cavities,cryptocrystalline precipitation,and euhedral crystal growth signified the effect of chemical activity after the deposition of grains in the lacustrine environment. | Rajesh Asthana Prakash Kumar Shrivastava Hari Bahadur Srivastava Mirza Javed Beg Pradeep Kumar | 2013 | Advances in Polar Science2013，24，4： | 2 |
| 11 | Influence of loading and heating processes on elastic and geomechanical properties of eclogites and granulites显示文摘Increased knowledge of the elastic and geomechnical properties of rocks is important for numerous engineering and geoscience applications(e.g. petroleum geoscience, underground waste repositories,geothermal energy, earthquake studies, and hydrocarbon exploration). To assess the effect of pressure and temperature on seismic velocities and their anisotropy, laboratory experiments were conducted on metamorphic rocks. P-(V_p) and S-wave(V_s) velocities were determined on cubic samples of granulites and eclogites with an edge length of 43 mm in a triaxial multianvil apparatus using the ultrasonic pulse emission technique in dependence of changes in pressure and temperature. At successive isotropic pressure states up to 600 MPa and temperatures up to 600 ℃, measurements were performed related to the sample coordinates given by the three principal fabric directions(x, y, z) representing the foliation(xy-plane), the normal to the foliation(z-direction), and the lineation direction(x-direction). Progressive volumetric strain was logged by the discrete piston displacements. Cumulative errors in V_p and V_s are estimated to be <1%. Microcrack closure significantly contributes to the increase in seismic velocities and decrease in anisotropies for pressures up to 200-250 MPa. Characteristic P-wave anisotropies of about 10% are obtained for eclogite and 3-4% in a strongly retrogressed eclogite as well as granulites. The wave velocities were used to calculate the geomechanical properties(e.g. density, Poisson's ratio, volumetric strain, and elastic moduli) at different pressure and temperature conditions. These results contribute to the reliable estimate of geomechanical properties of rocks. | Hem Bahadur Motra Sascha Zertani | 2018 | Journal of Rock Mechanics and Geotechnical Engineering2018，10，1： | 2 |
| 12 | Species Richness, Diversity and Density of Understory Vegetation along Disturbance Gradients in the Himalayan Conifer Forest显示文摘We investigated whether species richness, diversity and density of understory herbaceous plants differed along logging(gap) and grazing(primarily by cattle) disturbance gradients, and sought to identify drivers of richness, diversity and density of understory vegetation of logged sites. A factorial experiment was conducted in the mixed conifer forest of Gidakom in Western Bhutan. Levels of the logging treatment included small(0.15 – 0.24 ha), medium(0.25 – 0.35 ha) and large(0.36 – 1.31 ha) gaps. The grazing treatment included grazed(primarily by cattle) and ungrazed(where herbivores were excluded by a fence) plots nested within each gap. Data were collected from 12 gaps(4 replicates at each level of logging) using the point intercept method. Shannon Weaver Diversity and Margalef's indices were used to estimate species diversity and describe species richness, respectively. Soil samples were analyzed for pH and nutrients. The interaction effect of logging and grazing was significant(p≤0.001) only on species diversity. Relative to ungrazed areas, species diversity was significantly higher(0.01≤p≤0.05) in medium grazed gaps. Under grazed conditions, soil P was negatively correlated with gap size and species diversity. While species diversity was positivelycorrelated(0.01≤p≤0.05) with soil N in grazed plots species richness was positively correlated(0.001≤p≤0.01) with soil N in ungrazed plots. Relative density of Yushania microphylla and Carex nubigena were higher under ungrazed conditions. Our study suggests that the combined effect of cattle grazing and logging results in higher species diversity of understory vegetation in medium and grazed gaps in mixed conifer forests of Bhutan,whereas increase or decrease in relative density of major species is determined primarily by the independent effects of grazing and logging. From management perspective, forest managers must refrain from creating large gaps to avoid loss of nutrients(mainly P and N), which may eventually affect tree regeneration. Managers intending to maintain understory vegetation diversity must consider the combined effects of grazing and logging, ensuring low to moderate grazing pressure. | Kesang WANGCHUK András DARABANT Prem Bahadur RAI Maria WURZINGER Werner ZOLLITSCH Georg GRATZER | 2014 | Journal of Mountain Science2014，11，5： | 2 |
| 13 | A Note on Quantiles in Large Samples显示文摘 | BAHADUR R R | 1966 | Annals of Mathematics and Statistics1966，，37： | 2 |
| 14 | Weight Loss During Radiotherapy for Head and Neck Malignancies: What Factors Impact It?显示文摘 | Anusheel Munshi Manish Bhushan Pandey Tarun Durga Kailash Chander Pandey Sudhir Bahadur Bidhu Kalyan Mohanti | 2003 | Nutrition and Cancer2003，，2： | 2 |
| 15 | Effect of nonionic surfactants in release media on accelerated in-vitro release profile of sirolimus eluting stents with biodegradable polymeric coating显示文摘It is a well-known fact that sirolimus(SRL) undergoes degradation process via hydrolysis in aqueous media, leading to incorrect assessment of drug amount and thus release characteristics of formulations.The main objective of the present study was to evaluate the effect of nonionic surfactants in media on invitro release profiles for sirolimus eluting stents(SES) coated with biodegradable polymeric matrix.Phosphate buffer and acetate buffer incorporating nonionic surfactants with varying concentrations were examined for adequate solubility and stability(by RP-HPLC). Good sink condition was achieved in phosphate buffer(at pH 4.0) with 1.0% Tween 20, 1.0% Brij 35% and 0.5% Brij 58. Hydrodynamic size(by DLS) and the micelle-water partition coefficient(P) with standard free energy of solubilization(ΔGs°) of drug were evaluated to get some understanding about the solubilization phenomena. About 80% of drug release during the period of 48 h was achieved in optimized drug release media which was 1.0% Tween20 in phosphate buffer pH 4.0. The obtained accelerated SRL release profile in optimized medium correlated well with the real time in-vitro release in phosphate buffer(pH 7.4). Surface morphology changes(by SEM), changes in gravimetric weights and molecular weight change(by GPC) were examined before and after drug release to understand the drug release mechanism which explains that the polymer did not undergo degradation during the drug release. | Ami Raval Pratap Bahadur Ankur Raval | 2018 | Journal of Pharmaceutical Analysis2018，8，1： | 2 |
| 16 | The development of transfer layers and their role in polymer tribology 显示文摘 | Shyam Bahadur | 2000 | Wear2000，245，12： | 2 |
| 17 | Effects of conservation measures on crop diversity and their implications for climate-resilient livelihoods: the case of Rupa Lake Watershed in Nepal显示文摘Agrobiodiversity conservation is vital for achieving sustainability, but empirical studies on the effects of different practices or measures on crop diversity are rare. This study aims to estimate the effects of raising conservation awareness(RCA),building diversity blocks(BDB), and their combination on crop diversity among 240 randomly selected households surrounding the Rupa Lake Watershed in Nepal. Based on descriptive analysis and multiple regression models, the results indicate that the two single measures had no significant effect on the numbers of crop species and varieties grown by households in 2018. However, the combination of RCA and BDB had a significantly positive effect on the number of crop varieties, especially for grain and vegetable crops. Considering that these crops are essential in the daily lives of local people, the results indicate that a strategy that combines both awareness raising and on-farm conservation measures can generate higher crop diversity and better serve the climate-resilient livelihoods of people in mountainous areas. | BAI Yun-li FU Chao THAPA Balaram RANA Ram Bahadur ZHANG Lin-xiu | 2022 | Journal of Mountain Science2022，19，4： | 2 |
| 18 | The effect of reinforcement and the synergism between CuS and carbon fiber on the wear of nylon显示文摘 | BAHADUR S FU Q GONG D | 1994 | Wear1994，178，12： | 1 |
| 19 | Pollen dimorphism in three heterostyled Rubiaceae显示文摘 | Bahadur B | 1968 | Rev Palaeobot Palynol1968，7，： | 1 |
| 20 | Efficient hydrogen peroxide decomposition on bimetallic Pt-Pd surfaces 显示文摘 | Hasnat M A Rahrnan M Maria Borhanuddin S M Siddiqua Ayesha Bahadur N M Karim M R | 2010 | Catalysis Communications2010，12，4： | 1 |
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