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Water ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 162
Author(s):  
Feihe Kong ◽  
Wenjin Xu ◽  
Ruichen Mao ◽  
Dong Liang

The groundwater-dependent ecosystem in the Gnangara region is confronted with great threats due to the decline in groundwater level since the 1970s. The aim of this study is to apply multiple trend analysis methods at 351 monitoring bores to detect the trends in groundwater level using spatial, temporal and Hydrograph Analysis: Rainfall and Time Trend models, which were applied to evaluate the impacts of rainfall on the groundwater level in the Gnangara region, Western Australia. In the period of 1977–2017, the groundwater level decreased from the Gnangara’s edge to the central-north area, with a maximum trend magnitude of −0.28 m/year. The groundwater level in 1998–2017 exhibited an increasing trend in December–March and a decreasing trend in April–November with the exception of September when compared to 1978–1997. The rainfall + time model based on the cumulative annual residual rainfall technique with a one-month lag during 1990–2017 was determined as the best model. Rainfall had great impacts on the groundwater level in central Gnangara, with the highest impact coefficient being 0.00473, and the impacts reduced gradually from the central area to the boundary region. Other factors such as pine plantation, the topography and landforms, the Tamala Limestone formation, and aquifer groundwater abstraction also had important influences on the groundwater level.


Author(s):  
Xiangyu Zheng ◽  
Christina Deacon ◽  
Abigail J King ◽  
Daniel R Machin

Many individuals in industrialized societies consume a high salt, western diet, however, the effects of this diet on microcirculatory properties and glycocalyx barrier function are unknown. Young genetically heterogeneous male and female mice underwent 12 weeks of normal chow diet (NC), NC diet with 4% salt (NC4%), western diet (WD), or WD with 4% salt (WD4%). Microcirculatory properties and glycocalyx barrier function were evaluated in the mesenteric microcirculation using an intravital microscope equipped with an automated capture and analysis system. Total microvascular density summed across 4-25 μm microvessel segment diameters was lower in NC4% compared to NC and WD (P<0.05). Perfused boundary region (PBR), a marker of glycocalyx barrier function, averaged across 4-25 μm microvessel segment diameters was similar between NC and NC4%, as well as between WD and WD4% (P>0.05). PBR was lower in WD and WD4% compared to NC and NC4% (P<0.05), indicating augmented glycocalyx barrier function in WD and WD4%. There were strong, inverse relationships between PBR and adiposity and blood glucose (r=-0.44 to -0.61, P<0.05). In summary, NC4% induces deleterious effects on microvascular density, whereas WD augments glycocalyx barrier function. Interestingly, the combination of high salt, western diet in WD4% resulted in lower total microvascular density like NC4% and augmented glycocalyx barrier function like WD. These data suggest distinct microcirculatory adaptations to high salt and western diets that coincide when these diets are combined in young genetically heterogeneous male and female mice.


2022 ◽  
Author(s):  
Hao Mou ◽  
Yi-Zhou Jin ◽  
Juan Yang ◽  
Xu Xia ◽  
Yu-Liang Fu

Abstract Through diagnosing plasma density and calculating the intensity of microwave electric field, four 10cm electron cyclotron resonance (ECR) ion sources with different magnetic field structures are studied to reveal the inside interaction between plasma, magnetic field and microwave electric field. From the diagnosing result it can be found that the plasma density distribution is controlled by the plasma generation and electron loss volumes associated with magnetic field and microwave power level. Based on the cold plasma hypothesis and diagnosing result, the microwave electric field intensity distribution in the plasma is calculated. The result shows that the plasma will significantly change the distribution of microwave electric field intensity to form a bow shape. From the boundary region of the shape to the center, the electric field intensity varies from higher to lower and the diagnosed density inversely changes. If the bow and its inside lower electric field intensity region is close to the screen grid, the performance of ion beam extracting will be better. The study can provide useful information for the creating of 10cm ECR ion source and understanding its mechanism.


2021 ◽  
pp. 1-14
Author(s):  
Harish Garg ◽  
Sultan S. Alodhaibi ◽  
Hamiden Abd El-Wahed Khalifa

Rough set theory, introduced by Pawlak in 1981, is one of the important theories to express the vagueness not by means of membership but employing a boundary region of a set, i.e., an object is approximately determined based on some knowledge. In our real-life, there exists several parameters which impact simultaneously on each other and hence dealing with such different parameters and their conflictness create a multi-objective nonlinear programming problem (MONLPP). The objective of the paper is to deal with a MONLPP with rough parameters in the constraint set. The considered MONLPP with rough parameters are converted into the two-single objective problems namely, lower and upper approximate problems by using the weighted averaging and the ɛ- constraints methods and hence discussed their efficient solutions. The Karush-Kuhn-Tucker’s optimality conditions are applied to solve these two lower and upper approximate problems. In addition, the rough weights and the rough parameter ɛ are determined by the lower and upper the approximations corresponding each efficient solution. Finally, two numerical examples are considered to demonstrate the stated approach and discuss their advantages over the existing ones.


2021 ◽  
Vol 132 (1) ◽  
Author(s):  
S. M. Edwards ◽  
R. E. Hewitt

AbstractWe show that a new class of steady linear eigenmodes exist in the Falkner–Skan boundary layer, associated with an algebraically developing, thermally coupled three-dimensional perturbation that remains localised in the spanwise direction. The dominant mode has a weak temperature difference that decays (algebraically) downstream, but remains sufficient (for favourable pressure gradients that are below a critical level) to drive an algebraically growing disturbance in the velocity field. We determine the critical Prandtl number and pressure gradient parameter required for downstream algebraic growth. We also march the nonlinear boundary-region equations downstream, to demonstrate that growth of these modes eventually gives rise to streak-like structures of order-one aspect ratio in the cross-sectional plane. Furthermore, this downstream flow can ultimately become unstable to a two-dimensional Rayleigh instability at finite amplitudes.


2021 ◽  
Vol 8 (4) ◽  
pp. 2084-2094
Author(s):  
Vilat Sasax Mandala Putra Paryoko

Proportional Feature Rough Selector (PFRS) merupakan sebuah metode seleksi fitur yang dikembangkan berdasarkan Rough Set Theory (RST). Pengembangan ini dilakukan dengan merinci pembagian wilayah dalam set data menjadi beberapa bagian penting yaitu lower approximation, upper approximation dan boundary region. PFRS memanfaatkan boundary region untuk menemukan wilayah yang lebih kecil yaitu Member Section (MS) dan Non-Member Section (NMS). Namun PFRS masih hanya digunakan dalam seleksi fitur pada klasifikasi biner dengan tipe data teks. PFRS ini juga dikembangkan tanpa memperhatikan hubungan antar fitur, sehingga PFRS memiliki potensi untuk ditingkatkan dengan mempertimbangkan korelasi antar fitur dalam set data. Untuk itu, penelitian ini bertujuan untuk melakukan penyesuaian PFRS untuk bisa diterapkan pada klasifikasi multi-label dengan data campuran yakni data teks dan data bukan teks serta mempertimbangkan korelasi antar fitur untuk meningkatkan performa klasifikasi multi-label. Pengujian dilakukan pada set data publik yaitu 515k Hotel Reviews dan Netflix TV Shows. Set data ini diuji dengan menggunakan empat metode klasifikasi yaitu DT, KNN, NB dan SVM. Penelitian ini membandingkan penerapan seleksi fitur PFRS pada data multi-label dengan pengembangan PFRS yaitu dengan mempertimbangkan korelasi. Hasil penelitian menunjukkan bahwa penggunaan PFRS berhasil meningkatkan performa klasifikasi. Dengan mempertimbangkan korelasi, PFRS menghasilkan peningkatan akurasi hingga 23,76%. Pengembangan PFRS juga menunjukkan peningkatan kecepatan yang signifikan pada semua metode klasifikasi sehingga pengembangan PFRS dengan mempertimbangkan korelasi mampu memberikan kontribusi dalam meningkatkan performa klasifikasi.


Geology ◽  
2021 ◽  
Author(s):  
Jyotirmoy Paul ◽  
Attreyee Ghosh

Thick and highly viscous roots are the key to cratonic survival. Nevertheless, cratonic roots can be destroyed under certain geological scenarios. Eruption of mantle plumes underneath cratons can reduce root viscosity and thus make them more prone to deformation by mantle convection. It has been proposed that the Indian craton could have been thinned due to eruption of the Réunion plume underneath it at ca. 65 Ma. In this study, we constructed spherical time-dependent forward mantle convection models to investigate whether the Réunion plume eruption could have reduced the Indian craton thickness. Along with testing the effect of different strengths of craton and its surrounding asthenosphere, we examined the effect of temperature-dependent viscosity on craton deformation. Our results show that the plume-induced thermomechanical erosion could have reduced the Indian craton thickness by as much as ~130 km in the presence of temperature-dependent viscosity. We also find that the plume material could have lubricated the lithosphere-asthenosphere boundary region beneath the Indian plate. This could be a potential reason for acceleration of the Indian plate since 65 Ma.


2021 ◽  
Vol 932 ◽  
Author(s):  
Pierre Ricco ◽  
Claudia Alvarenga

The development and growth of unsteady three-dimensional vortical disturbances entrained in the entry region of a circular pipe is investigated by asymptotic and numerical methods for Reynolds numbers between $1000$ and $10\,000$ , based on the pipe radius and the bulk velocity. Near the pipe mouth, composite asymptotic solutions describe the dynamics of the oncoming disturbances, revealing how these disturbances are altered by the viscous layer attached to the pipe wall. The perturbation velocity profiles near the pipe mouth are employed as rigorous initial conditions for the boundary-region equations, which describe the flow in the limit of low frequency and large Reynolds number. The disturbance flow is initially primarily present within the base-flow boundary layer in the form of streamwise-elongated vortical structures, i.e. the streamwise velocity component displays an intense algebraic growth, while the cross-flow velocity components decay. Farther downstream the disturbance flow occupies the whole pipe, although the base flow is mostly inviscid in the core. The transient growth and subsequent viscous decay are confined in the entrance region, i.e. where the base flow has not reached the fully developed Poiseuille profile. Increasing the Reynolds number and decreasing the frequency causes more intense perturbations, whereas small azimuthal wavelengths and radial characteristic length scales intensify the viscous dissipation of the disturbance. The azimuthal wavelength that causes the maximum growth is found. The velocity profiles are compared successfully with available experimental data and the theoretical results are helpful to interpret the only direct numerical dataset of a disturbed pipe-entry flow.


2021 ◽  
Vol 2021 (12) ◽  
Author(s):  
Varun Gupta

Abstract We study classical M5 brane solutions in the probe limit in the AdS7× S4 background geometry that preserve the minimal amount of supersymmetry. These solutions describe the holography of codimension-2 defects in the 6d boundary dual $$ \mathcal{N} $$ N = (0, 2) supersymmetric gauge theories. The general solution is described in terms of holomorphic functions that satisfy a scaling condition. We show the behavior of the world-volume of a special class of BPS solutions near the AdS boundary region can be characterized by general equations, which describe it as intersections of the zeros of holomorphic functions in three complex variables with a 5-sphere.


2021 ◽  
Author(s):  
Nirmal Bisai ◽  
Santanu Banerjee ◽  
Stewart Zweben ◽  
Abhijit Sen

Abstract Abstract Anomalous plasma transport in the boundary region of a tokamak plasma is commonly associated with the formation and evolution of coherent density structures known as blobs. Recently, a theory for a universal mechanism of plasma blob formation has been put forward. It is based on a breaking process of a radially elongated streamer due to poloidal and radial velocity shears. The theory is well supported by two-dimensional and three-dimensional numerical simulation results but lacks experimental validation. In this work, we report the first ever experimental validation of this universal criterion by testing it against NSTX data on blobs obtained using the gas-puff imaging (GPI) diagnostic. It is found that the criterion is widely satisfied in most L-mode discharges and may explain the significantly larger number of blob events. We also validate the theoretical criterion against ADITYA Langmuir probe data taken in the scrape-off layer region.


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