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The REMO Ocean Data Assimilation System into HYCOM(RODAS_H):General Description and Preliminary Results

Atmospheric and Oceanic Science Letters 2014年第5期7卷 464-470页

作者： Clemente Augusto Souza TANAJURA Alex Novaes SANTANA Davi MIGNAC Leonardo Nascimento LIMA konstantin BELYAEV XIE Ji-Ping Physics Institute Federal University of Bahia (UFBA) Salvador 40170-280 Brazil Oceanographic Modeling and Observation Network (REMO) Center for Research in Geophysics and Geology Federal University of Bahia (UFBA) Salvador 40170-280 Brazil Ocean Sciences Department University of California Santa Cruz (UCSC) USA Graduate Program in Geophysics Federal University of Bahia (UFBA) Salvador Brazil Shirshov Institute of Oceanology Russian Academy of Sciences (SHIRSHOV/RAS) Moscow Russia Institute of Atmospheric Physics(IAP) Chinese Academy of Sciences (CAS)

The first version of the Brazilian Oceano- graphic Modeling and Observation Network （REMO） ocean data assimilation system into the Hybrid Coordi- nate Ocean Model （HYCOM）（RODAS H） has recently been constructed for research and operational purposes. The system is based on a multivariate Ensemble Optimal Interpolation （EnOI） scheme and considers the high fre- quency variability of the model error co-variance matrix. The EnOl can assimilate sea surface temperature （SST）, satellite along-track and gridded sea level anomalies （SLA）, and vertical profiles of temperature （T） and salinity （S） from Argo. The first observing system experiment was carried out over the Atlantic Ocean （78°S-50°N, 100°W-20°E） with HYCOM forced with atmospheric reanalysis from 1 January to 30 June 2010. Five integra- tions were performed, including the control run without assimilation. In the other four, different observations were assimilated： SST only （A SST）; Argo T-S profiles only （AArgo）; along-track SLA only （A_SLA）; and all data employed in the previous runs （A_All）. The A_SST, A_Argo, and A_SLA runs were very effective in improv- ing the representation of the assimilated variables, but they had relatively little impact on the variables that were not assimilated. In particular, only the assimilation of S was able to reduce the deviation of S with respect to ob- servations. Overall, the A_All run produced a good analy- sis by reducing the deviation of SST, T, and S with respect to the control run by 39%, 18%, and 30%, respectively, and by increasing the correlation of SLA by 81%.

关键词： ocean data assimilation ensemble optimalinterpolation observing system experiment HYCOM Atlantic Ocean

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A Direct Effective Viscosity Approach for Modeling and Simulating Bingham Fluids with the Cumulant Lattice Boltzmann Method

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Open Journal of Fluid Dynamics 2021年第1期11卷 34-54页

作者： Martin Geier konstantin Kutscher Manfred Krafczyk Institute for Computational Modeling in Civil Engineering TU Braunschweig Braunschweig Germany

Modeling of fluids with complex rheology in the lattice Boltzmann method (LBM) is typically realized through the introduction of an effective viscosity. For fluids with a yield stress behavior, such as so-called Bingham fluids, the effective viscosity has a singularity for low shear rates and may become negative. This is typically avoided by regularization such as Papanastasiou’s method. Here we argue that the effective viscosity model can be re-interpreted as a generalized equilibrium in which no violation of the stability constraint is observed. We implement a Bingham fluid model in a three-dimensional cumulant lattice Boltzmann framework and compare the direct analytic effective viscosity/generalized equilibrium method to the iterative approach first introduced by Vikhansky which avoids the singularity in viscosity that can arise in the analytic method. We find that both methods obtain similar results at coarse resolutions. However, at higher resolutions the accuracy of the regularized method levels off while the accuracy of the direct method continuously improves. We find that the accuracy of the proposed direct method is not limited by the singularity in viscosity indicating that a regularization is not strictly necessary.

关键词： Lattice Boltzmann Method Bingham Fluids Generalized Equilibrium

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Improving the Energy Performance of a High-Pressure Hydraulic Turbine by Researching the Flow in the Flow Part

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Journal of Power and Energy Engineering 2022年第4期10卷 27-37页

作者： konstantin Mironov Yuliia Oleksenko Aminjon Gulakhmadov Department of Hydraulic Machines named after Academician G.F. Proskura National Technical University “Kharkiv Polytechnic Institute” Kharkiv Ukraine Ministry of Energy and Water Resources of the Republic of Tajikistan Dushanbe Tajikistan Research Center for Ecology and Environment of Central Asia Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China Institute of Water Problems Hydropower and Ecology of the National Academy of Sciences of Tajikistan Dushanbe Tajikistan

In this study, the goal is to increase the efficiency of a high-pressure hydraulic turbine. The goal is achieved by numerical flow simulation using CFX-TASCflow. This approach reduces costs and time compared to the experimental approach and allows for improving the turbine productivity and its design. The analysis of energy losses in the flow part of the turbine Fr500, as well as the analysis of the influence of the opening of the guide vanes on changes in energy losses. The results showed that the greatest losses occur in the guide vane 3.02% based on the two-dimensional model and 2.5% based on the 3D model, which significantly affects the efficiency. The analysis was carried out using programs for calculating fluid flow in two-dimensional and three-dimensional formulations. With the help of the study, the main energy problem is solved—increasing efficiency.

关键词： Francis Turbine Efficiency Spiral Case Runner Guide Vane Draft Tube

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GIS-Approach to Estimate Ground Transport Accessibility of Forest Resources (Case Study: Novosibirsk Region, Siberian Federal District, Russia)

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Journal of Geographic Information System 2020年第5期12卷 451-469页

作者： Ekaterina Podolskaia Dmitriy Ershov konstantin Kovganko Laboratory of Forest Ecosystems Monitoring Center for Forest Ecology and Productivity Russian Academy of Sciences Moscow Russia

In the big forest countries, there is an actual challenge of accessing the forests for their resources, operational wildfire management, and economic estimations for various purposes. In Russia, there are two ways to access the forests: by air and by ground means. The first way is quite expensive for any country. The second one is less expensive but has the spatial planning challenges to create access routes by existing public roads and forest glades. Regional authorities and firefighting departments are paying attention to the access by ground means, but there is a certain room to improve their management and cooperation methods on a limited budget. These tasks could be solved by GIS-technologies in a more operational manner to automate the routes’ construction especially during the fire season. We used combined geoinformation technology (developed previously) and satellite product, namely vegetation map from Moderate Resolution Imaging Spectroradiometer (MODIS) to estimate how accessible any forest area is when moving by public roads and forest glades from a fire station as a starting point. These stations are the main centers to fight the forest fires within the territory of ground protection zones in Russia and we have considered them as the logistic centers to manage the forest resources also. Transport model was created in two variants: no-barriers and barriers-based (forestries). By using these two models we have shown two different scenarios of action. The key area was Novosibirsk Region located in the Siberian Federal District, Russia. We have created a series of maps to show the transport accessibility of forest areas from the fire stations. Estimation of “located” pixels or forest areas accessible from the fire stations for the key area is about 66% - 83%;the most accessible forest type is mixed forests. The number of inaccessible pixels has been increased by more than two times in barriers scenario. Technology can be used for different thematic data sour

关键词： Ground Accessibility GIS Barriers Forest Resources Forestry Fire Station MODIS

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Comparison of pulse-modulated and continuous operation modes of a radio-frequency inductive ion source

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Plasma Science and Technology 2023年第2期25卷 131-145页

作者： Ilya ZADIRIEV Elena KRALKINA konstantin VAVILIN Alexander NIKONOV Georgy SHVIDKIY Physical Electronics Department Faculty of PhysicsLomonosov Moscow State UniversityMoscow 119991Russia

The paper describes an experimental study of the characteristics of a pulse-modulated radiofrequency(RF)discharge sustained at low pressures,typical of the operating modes of RF gridded ion *** motivation for the study is the question of whether the RF pulsemodulated mode can increase the efficiency of the ion *** ion current values extracted from an RF inductive ion source operating in continuous and pulse-modulated modes were *** experimental data were also compared with the parameter calculations based on a0D numerical model of the *** measurements showed that the pulse-modulated operation mode of the RF ion source had a noticeable advantage when the power of the RF generator was 140 W or ***,as the generator power increased,the advantage was lost because the pulse-modulated operation mode,having a higher RF power instant value,entered the region of existence sooner than the continuous mode,where the ion production cost begins to grow with RF power.

关键词： discharge plasma radio frequency(RF) pulse electrons ions

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气体动力学方程系统的数值方法

气体动力学方程系统的数值方法

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作者： Bushuev konstantin 华东师范大学

学位级别：硕士

在现代科学和技术的许多领域中,许多问题涉及气体动力学方程组。气体动力学方程组的强烈的非线性使得数值方法成为求解方程组最有效和最通用的方法之一。本文将给出在拉格朗日坐标下对于一维气体动力学方程组系统的一类数值解法,同...

在现代科学和技术的许多领域中,许多问题涉及气体动力学方程组。气体动力学方程组的强烈的非线性使得数值方法成为求解方程组最有效和最通用的方法之一。本文将给出在拉格朗日坐标下对于一维气体动力学方程组系统的一类数值解法,同时给出几个数值算例。对气体动力学方程组的相关科学论文数量与日俱增,这个现象说明人们对于相关的科学计算领域的兴趣越来越浓厚。气体动力学方程组的数值解法目前仍是一个热门的数学研究分支。一维气体动力学方程的数值解的发展得益于文献[1],[2],[3],[4],[5]和[17],完整的概述也可以在[10]找到。一些气体动力学方程可以考虑拉格朗日方法（如爆炸的问题、气流的问题等）,所以许多的论文致力于构建拉格朗日变量的数值解法（[9],[16]）。对于一维问题,通常不只是考虑拉格朗日变量方法,也有使用拉格朗日质量坐标法（[17]）。然而拉格朗日质量坐标法对于高维问题只能用于圆柱或球对称的情况。许多有限差分方案的另一个缺点：算法仅适用于解是光滑的情况;在解不光滑处,采用的算法必须有所改变。这些问题的精确计算中,一个关键的问题是如何保证气体动力学方程组近似解在不连续处的实际逼近精度。克服困难的方法之一是在气体不连续的位置采用显格式（[4],[7]）。然而,虽然这种方法提供了必要的精度,但实现太过于复杂,特别是在多维的情况下,实际应用很难找到所有的不连续性（[1]）。另一种方法是使用同种的差分格式（[3],[14]）,其允许算法单独进行光滑解和间断解的计算。一个最基本的原则是由A. Tikhonov和A. A. Samarskiy提出的守恒型差分格式。[18]指出,在计算中,这一原则的违反可能会导致误差,这种误差即使网格细化也不会消失的。因此,目前只讨论守恒型的差分格式。然而,同种（尽管是守恒的）差分格式经常处理以下情况：控制方程的直接近似导致间断点附近的强烈振荡（s[17]）。一种常用的消除这个缺陷的方法是引入所谓的人工粘性的项（[15]）,即在带黏性和其它系数随网格细化而趋于零的耗散过程的近似解的差分方程中引入附加项。这种方法已经在用拉格朗日变量解决气体动力学问题中广泛应用（[8]）,因为拉格朗日坐标的广泛使用实际上在显式格式中分配了接触不连续性,只保留了如冲击波的不连续性,这有利于人工粘性系数的正确选择。在欧拉和欧拉-拉格朗日变量中,最重要的参数是耗散传播接触边界。因此,由于算法格式的高要求性和现有的算法的不足,对于气体动力学方程组会出现新的差分格式。本文所提出的算法在解的光滑区域具有二阶逼近精度,并同时具有单调性。有限差分格式建立在积分插值法上,所以差分格式自然满足原问题的守恒定律。算法在不做修改的情况下可以建立不同的解。它同样可推广用于n维的情况,并进一步得到拉格朗日变量和欧拉变量的解。

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Mathematical Programming Method as a Means of Calibration of NIR Analyzers

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Journal of Chemistry and Chemical Engineering 2012年第8期6卷 692-697页

作者： Ilya Skutin konstantin Zharinov Maria Sushkova Department of Chemical Engineering Control St. Petersburg State Institute of Technology St. Petersburg 190013 Russia Lumex Ltd. St. Petersburg 192029 Russia

In addition to the conventional methods of the calibration model construction, such as PCR （principal components regression） and PLS （partial least-squares）, a MPM （mathematical programming method） is developed and proposed for practical use in NIR analyses of agricultural and food products. The proposed method involves the mathematical programming techniques to seek the regression coefficients for the calibration model calculation. It is based on the optimization theory used for finding the extremum of the objective function in the given domain of a vector space and employs the method of the complementarity problems solving. The MPM algorithm is described in detail. The MPM was tested on an InfraLUM FT-10 NIR analyzer of Lumex company with samples of dry milk （for fat）, corn （for protein） and rye flour （for moisture）. The obtained results show that the MPM can be used for constructing multivariate calibrations with the qualitative characteristics superior over those of the classical PCR and PLS methods of analysis.

关键词： Chemometrics multivariate calibration mathematical programming simplex table method.

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A Novel Method of Fruit Raw Material Reprocessing

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Engineering（科研） 2010年第12期2卷 962-968页

作者： Alexander A. Emelyanov konstantin A. Emelyanov 不详

We introduced a method of deep resources-economy reprocessing of fruit raw material. Based on the raw material fractionation at decreased temperatures the method results in the production of bioactive food stuffs, which are dry juice and refuse and natural water. The method includes the production of directly extracted juice and pulp refuse, juice evaporation in vacuum with the production of concentrate and natural water, and air drying the concentrate and the refuse. The method is realized for garden strawberry and cucurbit pulp. The mass concentration of solid in the fractions of cucurbit pulp is defined and the specific weight of the fractions are defined. It is shown that the solid of the cucurbit pulp is uniformly allocated between the fractions and amounts 34% for the dry juice, 31% for the dry refuse, and 35% for the natural water. Food and biological values of the cucurbit pulp fractions are determined. It is determined that the cucurbit includes silicium, nickel, and chromium. Silicium is contained only in dry fractions;nickel is present everywhere;chromium is discovered only in the natural water. Food and biological values of the cucurbit pulp are defined and their allocation between the fractions is determined. Separate components concentrations of the solid considerably differ between the fractions. Thus, two thirds of pulp protein is concentrated in the dry juice and a third is concentrated in the refuse. The natural water contains up to 90% of fat and sugar, from a half to two thirds of B-group vitamins, and the bulk of the mineral substances (K, Na, Ca, Mg, S, Co, Cu, Ni, Cr, and Zn), which concentration composes from 73% for potassium up to 100% for chromium.

关键词： Fruit Raw Material Vacuum Evaporation Air Drying Bioactive Fractions Dry Juice Dry Pulp Refuse Nature Fruit Water

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Lingual lymph nodes:Anatomy,clinical considerations,and oncological significance

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World Journal of Clinical Oncology 2020年第6期11卷 337-347页

作者： Shalva R Gvetadze konstantin D Ilkaev Central Research Institute of Dentistry and Maxillofacial Surgery Moscow 119991Russia Blokhin National Medical Research Center of Oncology Moscow 115478Russia

Lingual lymph nodes are an inconstant group of in-transit nodes,which are located on the route of lymph drainage from the tongue mucosa to the regional nodes in neck levels I and *** is growing academic data on the metastatic spread of oral cancer,particularly regarding the spreading of oral tongue squamous cell carcinoma to lingual *** nodes are not currently included in diagnostic and treatment protocols for oral tongue *** information on surgical anatomy,clinical observations,means of detection,and prognostic value is *** obtained incidence of lingual nodes ranges from 8.6%to 30.2%.Incidence of lingual lymph node metastasis ranges from 1.3%to 17.1%.It is clear that lymph nodes that bear intervening tissues from the floor of the mouth should be removed to improve loco-regional *** resection volume,which is required for the surgical treatment of lingual node metastasis,cannot be implied to every tongue cancer *** these lesions significantly influence prognosis,special efforts of their detection must be ***,every tongue cancer patient must be investigated for the existence of lingual lymph node *** tracing methods,which are currently implied for sentinel lymph node biopsies,may improve the detection of lingual lymph nodes.

关键词： Lingual lymph node Sublingual lymph node Tongue cancer Regional metastasis Lymph drainage Head neck region En-bloc resection

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Chronic hepatitis C virus infection:Prevalence of extrahepatic manifestations and association with cryoglobulinemia in Bulgarian patients

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World Journal of Gastroenterology 2007年第48期13卷 6518-6528页

作者： Diana V Stefanova-Petrova Anelia H Tzvetanska Elisaveta J Naumova Anastasia P Mihailova Evgenii A Hadjiev Rumiana P Dikova Mircho I Vukov konstantin G Tchernev Department of Internal Diseases and Gastroenterology University Hospital Alexandrovska Viral Laboratory University Pediatric Hospital Central Laboratory of Immunology University Hospital Alexandrovska Department of Hematology University Hospital Alexandrovska Department of Pathology University Hospital Alexandrovka National Centre for Health Information

AIM: To assess the prevalence of extrahepatic manifestations in Bulgarian patients with chronic hepatitis C virus (HCV) infection and identify the clinical and biological manifestations associated with cryoglobulinemia. METHODS: The medical records of 136 chronically infected HCV patients were reviewed to assess the prevalence of extrahepatic manifestations. Association between cryoglobulin-positivity and other manifestations were identified using χ2 and Fisher’s exact test. Risk factors for the presence of extrahepatic manifestations were assessed by logistic regression analysis. RESULTS: Seventy six percent (104/136) of the patients had at least one extrahepatic manifestation. Clinical manifestations included fatigue (59.6%), kidney impairment (25.0%), type 2 diabetes (22.8%), paresthesia (19.9%), arthralgia (18.4%), palpable purpura (17.6%), lymphadenopathy (16.2%), pulmonary fi brosis (15.4%), thyroid dysfunction (14.7%), Raynaud’s phenomenon (11.8%), B-cell lymphoma (8.8%), sicca syndrome (6.6%), and lichen planus (5.9%). The biological manifestations included cryoglobulinproduction (37.5%), thrombocytopenia (31.6%), and autoantibodies: anti-nuclear (18.4%), anti-smooth muscle (16.9%), anti-neutrophil cytoplasm (13.2%) and anti-cardiolipin (8.8%). All extrahepatic manifestations showed an association with cryoglobulin-positivity, with the exception of thyroid dysfunction, sicca syndrome, and lichen planus. Risks factors for the presence of extrahepatic manifestations (univariate analysis) were: age ≥ 60 years, female gender, virus transmission by blood transfusions, longstanding infection (≥ 20 years), and extensive liver fi brosis. The most signifi cant risks factors (multivariate analysis) were longstanding infection and extensive liver fi brosis. CONCLUSION: We observed a high prevalence of extrahepatic manifestations in patients with chronic HCV infection. Most of these manifestations were associated with impaired lymphoproliferation and cryoglobulin produc

关键词： Hepatitis C Liver cirrhosis Extrahepatic manifestations

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