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Effects of clump spacing on nutrient distrib.tion and root activity of Dendrocalamus strictus in the humid region of Kerala,peninsular India

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Journal of Forestry Research 2017年第6期28卷 1133-1144页

作者： b. H. Kittur K. Sudhakara b. mohan Kumar T. K. Kunhamu P. Sureshkumar Department of Silviculture and Agroforestry College of Forestry Kerala Agricultural UniversityVellanikkara Thrissur Kerala 680656 India School of Ecology and Environment Studies Nalanda University Rajgir District Nalanda Bihar 803116 India Department of Soil Science and Agricultural Chemistry Radio-tracer Laboratory College of Horticulture Kerala Agricultural University Vellanikkara ThrissurKerala 680656 India

The humid agroclimatic conditions of Kerala,India permit the cultivation of an array of b.mb.o species of which Dendrocalamus strictus Roxb.(Nees.) is an important one on account of its high growth rate and multiple uses. Stand density, a potential tool in controlling the productivity of woody ecosystems, its effect on growth and root distrib.tion patterns may provide a b.tter understanding of productivity optimization especially when b.mb.o-b.sed intercropping options are *** attrib.tes of 7-year-old b.mb.o(D. strictus) stands managed at variab.e spacing(4×4 m, 6×6 m, 8×8 m,10×10 m, 12×12 m) were studied. Functional root activity among b.mb.o clumps were also studied using a radio tracer soil injection method in which the radio isotopeP was applied to soil at varying depths and lateral distances from the clump. Results indicate that spacing exerts a profound influence on growth of b.mb.o. Widely spaced b.mb.o exhib.ted higher clump diameters and crown widths while clump heights were b.tter under closer spacing. Clump height was 30% lower and Db. 52%higher at the widest spacing(12×12 m) compared to the closest spacing(4×4 m). With increasing soil depth and lateral distance, root activity decreased significantly. Root activity near the clump b.se was highest(809 counts per minute, cpm; 50 cm depth and 50 cm lateral distance) at 4×4 m. Tracer study further showed wider distrib.tion of root activity with increase in clump spacing. It may b. concluded that the intensive foraging zone of b.mb.o is within a 50-cm radius around the clump irrespective of spacing. N, P and K content in the upper 20 cm was 2197,21, and 203 kg/ha respectively for the closely spaced b.mb.o(4×4 m) which were significantly higher than corresponding nutrient content at wider spacings. Ab.ut 50% of N, P and K were present within the 0–20 cm soil layer, which decreased drastically b.yond the 20 cm *** results suggest that stand management practices through planting density regula

关键词： b.mb.o Clump spacing Functional root activity Radio tracer 32P Soil nutrients

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Delay Analysis Techniques Comparison

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Journal of Civil Engineering and Architecture 2011年第8期5卷 740-747页

作者： Khalid S. AI-Gahtani Satish b. mohan Department of Civil Engineering King Saud University Riyadh Saudi Arabia Department of Civil Structural ＆ Environmental Engineering State University of New York at Buffalo NY USA

Many techniques have b.en used in the courts to demonstrate the criticalities of a delay event on the project schedule. At this time, there is no standard method to analyze a delay claim. This paper first introduced a fictional case study that has most types of delay and acceleration events that might b. faced on a real project. The case study is applied to all current techniques of delay claims that have b.en identified from previous studies. The comparison uses the delay claim issues as criteria to evaluate all the delay claim techniques from the case study results. The case study result and discussion demonstrate that the Day-b.-Day technique satisfies all the desired criteria while other techniques lack some.

关键词： Construction scheduling claim delay CPM.

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Effect of Slow Cooling in Reducing Pore Size in a Sintered Powder Metallurgical 6061Aluminium Alloy

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Materials Sciences and Applications 2011年第7期2卷 870-877页

作者： S. Solay Anand b. mohan T. R. Parthasarathy 不详

The usage of powder metallurgy aluminium compacts in lieu of ferrous components in automotives helps to lower vehicle weight. The major drawb.ck in the commercially availab.e press sintered aluminium alloy is porosity which is mainly dependent on the powder metallurgical process parameters such as compaction pressure, sintering temperature and cooling rate after sintering. In this paper the effect of particle size and furnace controlled cooling after sintering on porosity level and micro hardness of an elemental 6061 aluminium alloy has b.en investigated. Aluminium particle sizes of 20 μm and 150 μm were used. The elemental 6061 aluminium alloy powders are warm compacted at 175 MPa. After sintering for ab.ut one hour at 600°C, the aluminium compacts were furnace cooled at the rate of 1°C /min to different temperatures of 500°C, 400°C, 300°C and 200?C. When the cooling temperature after sintering inside the furnace is effected at various temperatures from 600°C to 200°C, for a precipitate hardened aluminium compacts with aluminium particle size of 20 μm, the porosity level reduced b. 26% and that for aluminium particle size of 150μm, the porosity level reduced b. 23%. Marked improvement in micro hardness value is also ob.erved correspondingly.

关键词： Powder Metallurgy Particle Size Cooling Rate Precipitation Hardening Porosity

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Novel phenanthrene/b.b.nzyl trimers from the tub.rs of b.etilla striata attenuate neuroinﬂammation via inhib.tion of NF-κb.signaling pathway

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Chinese Journal of Natural Medicines 2024年第5期22卷 441-454页

作者： SHAO Siyuan SUN mohan MA Xianjie JIANG Jianwei TIAN Jinying ZHANG Jianjun YE Fei LI Shuai State Key Lab.ratory of b.oactive Sub.tance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Five novel(9,10-dihydro)phenanthrene and b.b.nzyl trimers,as well as two previously identified b.phenanthrenes and b.b.nzyls,were isolated from the tub.rs of b.etilla *** structures were elucidated through comprehensive analyses of NMR and HRESIMS spectroscopic *** ab.olute configurations of these compounds were determined b. calculating rotational energy b.rriers and comparison of experimental and calculated ECD *** 5b.and 6 exhib.ted inhib.tory effects on LPS-induced NO production in b.-2 cells,with IC_(50) values of 12.59±0.40 and 15.59±0.83μmol·L^(-1),respectively.A mechanistic study suggested that these compounds may attenuate neuroinflammation b. reducing the activation of the AKT/Iκb.NF-κb.signaling ***,compounds 3a,6,and 7 demonstrated significant PTP1b.inhib.tory activities,with IC_(50) values of 1.52±0.34,1.39±0.11,and 1.78±0.01μmol·L^(-1),*** investigation revealed that compound 3a might inhib.t LPS-induced PTP1b.overexpression and NF-κb.activation,thereb. mitigating the neuroinflammatory response in b.-2 cells.

关键词： b.etilla striata Phenanthrene/b.b.nzyl trimer NO inhib.tion AKT/Iκb.NF-κb.signaling pathway PTP1b.inhib.tory effect

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实现RSA公开密钥密码体制的快速算法

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信息安全与通信保密 1987年第2期 81-82页

作者： S. b. mohan ,b. S. Adiga ,王晓呜

本文给出了由Rivest,Shamir,Adleman三人提出的公开密钥密码体制的快速算法。该算法以Schonhage、Strassen提出的快速整数乘法以及本文提出的迭代除法为基础。

关键词：公开密钥密码体制不对称密钥密码体制 RSA 快速算法

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Machine learning for predicting the outcome of terminal b.llistics events

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Defence Technology（防务技术） 2024年第1期31卷 14-26页

作者： Shannon Ryan Neeraj mohan Sushma Arun Kumar AV Julian b.rk Tahrima Hashem Santu Rana Svetha Venkatesh Applied Artificial Intelligence Institute(A2I2) Deakin University75 Pigdons RdWaurn PondsVIC3216Australia

Machine learning(ML) is well suited for the prediction of high-complexity,high-dimensional prob.ems such as those encountered in terminal *** evaluate the performance of four popular ML-b.sed regression models,extreme gradient b.osting(XGb.ost),artificial neural network(ANN),support vector regression(SVR),and Gaussian process regression(GP),on two common terminal b.llistics’ prob.ems:(a)predicting the V50b.llistic limit of monolithic metallic armour impacted b. small and medium calib.e projectiles and fragments,and(b. predicting the depth to which a projectile will penetrate a target of semi-infinite *** achieve this we utilise two datasets,each consisting of approximately 1000samples,collated from pub.ic release *** demonstrate that all four model types provide similarly excellent agreement when interpolating within the training data and diverge when extrapolating outside this *** extrapolation is not advisab.e for ML-b.sed regression models,for applications such as lethality/survivab.lity analysis,such capab.lity is *** circumvent this,we implement expert knowledge and physics-b.sed models via enforced monotonicity,as a Gaussian prior mean,and through a modified loss *** physics-informed models demonstrate improved performance over b.th classical physics-b.sed models and the b.sic ML regression models,providing an ab.lity to accurately fit experimental data when it is availab.e and then revert to the physics-b.sed model when *** resulting models demonstrate high levels of predictive accuracy over a very wide range of projectile types,target materials and thicknesses,and impact conditions significantly more diverse than that achievab.e from any existing analytical *** with numerical analysis tools such as finite element solvers the ML models run orders of magnitude *** provide some general guidelines throughout for the development,application,and reporting of ML models in terminal b.llist

关键词： Machine learning Artificial intelligence Physics-informed machine learning Terminal b.llistics Armour

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Simulation and experimentation of Propeller-Savonius turb.ne tested underwater surface

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CLEAN ENERGY 2024年第3期8卷 20-33页

作者： Wuryanti, Sri Sasono, Teguh Manunggal, b.mb.ng P. Mursanto, Wahyu b. Sugianto Politekn Negeri b.ndung Politeknik Negeri Bandung Bandung Indonesia Politekn Negeri Padang Dept Mech Engn Padang Indonesia

Indonesia's vast maritime territory offers a unique opportunity for harnessing the potential Energy of seawater currents. This study explores the effectiveness of a comb.ned Savonius and propeller-type turb.ne system. The Savonius turb.ne, known for its efficiency in capturing ocean currents due to its large sweep area, is comb.ned with a propeller-type turb.ne to enhance rotational speed and power generation. A novel approach is employed to induce turb.lence and optimize energy extraction, first channeling water through the propeller turb.ne and then into the Savonius turb.ne. A comprehensive investigation is conducted through simulations and experimental tests within a controlled tunnel environment. The study explores the performance of two-b.aded and three-b.aded Propeller-Savonius configurations at varying inlet water velocities (0.1, 0.3, 0.6 and 1.0 m/s). The simulation incorporates a turb.lence model with 5% intensity and a hydraulic diameter of 0.216 m. Results indicate that the proposed configuration achieves a maximum power output of 2.0293 W with an impressive efficiency of 63.339% in simulation. Concurrently, experimental testing yields a peak efficiency of 61.335% and turb.ne power of 0.3951 W. The findings demonstrate the feasib.lity of the comb.ned turb.ne system and highlight the importance of turb.lence in optimizing energy extraction from seawater currents. This research contrib.tes valuab.e insights into the design and performance of hyb.id turb.nes for harnessing oceanic Energy, emphasizing the potential for sustainab.e power generation in maritime regions. The methodology and results presented herein offer a foundation for further exploration and refinement of seawater current energy conversion technologies. The study comb.nes a Savonius turb.ne and a propeller turb.ne to enhance rotational speed and power generation. CFD simulations and experiments document performance at different water velocities. The findings show that this system is promisi

关键词： hydro-turb.ne propeller -Savonius renewab.e energy water WIND TURb.NE PERFORMANCE b.ADES CFD RATIO

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Comb.ning stochastic density functional theory with deep potential molecular dynamics to study warm dense matter

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Matter and Radiation at Extremes 2024年第1期9卷 44-57页

作者： Tao Chen Qianrui Liu Yu Liu Liang Sun mohan Chen HEDPS CAPTCollege of Engineering and School of PhysicsPeking UniversityBeijing 100871People’s Republic of China

In traditional finite-temperature Kohn–Sham density functional theory(KSDFT),the partial occupation of a large numb.r of high-energy KS eigenstates restricts the use of first-principles molecular dynamics methods at extremely high ***,stochastic density functional theory(SDFT)can overcome this ***,SDFT and the related mixed stochastic–deterministic density functional theory,b.sed on a plane-wave b.sis set,have b.en implemented in the first-principles electronic structure software Ab.CUS[*** and ***,***.b.106,125132(2022)].In this study,we comb.ne SDFT with the b.rn–Oppenheimer molecular dynamics method to investigate systems with temperatures ranging from a few tens of eV to 1000 ***,we train machine-learning-b.sed interatomic models using the SDFT data and employ these deep potential models to simulate large-scale systems with long ***,we compute and analyze the structural properties,dynamic properties,and transport coefficients of warm dense matter.

关键词： stochastic theory functional

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Solving the Three-Neutrino Prob.em as One of the Three-b.dy Prob.ems in Physics

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第1期10卷 197-227页

作者： Zoran b. Todorovic Faculty of Electrical Engineering Department of Physics University of Belgrade Belgrade Serbia

b. using the standard PMNS (Pontecorvo-Maki-Nakagawa-Sakata) mixing matrix and applying the rule for the sum of the oscillation prob.b.lities of three neutrinos, the equations of motion were derived in which the Dirac CP violating phase appeared as an unknown quantity. The equations of motion were separately derived for each of the three possib.e transitions for flavor-neutrino oscillations. Two roots of those equations were ob.ained in the form of two formulas for the Dirac CP violating phase with opposite signs. In the mathematical sense, the connection b.tween those formulas was estab.ished in order to maintain the continuous process of oscillation of three neutrinos. This made it possib.e to calculate the numerical value for the Dirac CP violating phase, the Jarlskog invariant and to write the general form of the PMNS mixing matrix in the final form in which all its elements are defined with explicit numerical values.

关键词： Ordinary Neutrino PMNS Matrix Dirac CPV Phase Jarlskog Invariant

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On the Numb.r of Primes in the Interval (x, 2x) b. an Elementary Method

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Advances in Pure Mathematics 2024年第1期14卷 16-29页

作者： Sudhindra b. Kittur Independent Researcher Mumbai India

An elementary formula to know the numb.r of primes in the interval (x, 2x) close to the exact figure for a fixed x is given here. A new elementary equation is derived (a relation b.tween prime numb.rs and composite numb.rs distrib.ted in the interval [1, 2x]). An elementary method to know the numb.r of primes in a given magnitude is suitab.y placed in the form of a general formula, and we have proved it. The general formula is applied to the terms of the equation, and a tactical simplification of the terms gives rise to an expression whose verification envisages scope for its further studies.

关键词： Prime Numb.rs Composite Numb.rs Expression Integers

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