scholarly journals Specificity of the seismic material obtained in complex seismo geological conditions (swamp zone)

2019 ◽  
Author(s):  
А.А. Левицкий ◽  
А.В. Рудаков ◽  
М.С. Левицкая
Keyword(s):  
Negative Impact ◽  
Seismic Source ◽  
Integrated Approach ◽  
Seismic Exploration ◽  
Near Surface ◽  
Factors Affecting ◽  
Geological Conditions ◽  
Seismic Recording ◽  
Surface Section

Основная цель работы – описание новых технических и методологических средств, используемых АО «Южморгеология» при проведении полевых сейсморазведочных работ МОГТ 3D в лиманно-плавневых зонах Славянского района Краснодарского края в 2014-2015 гг. Представлены основные результаты опытных работ, обоснован выбор параметров съемки и их влияние на качество сейсмической записи: заглубление пневмоисточников BOLT 2200LL-BHS, количество накоплений возбуждения и необходимая глубина погружения датчиков регистраторов. В качестве датчиков регистраторов использовались маршфоны «СВГ-6», которые задавливались с помощью металлического шеста с креплением на конце на глубину 1,0–2,5 м до достижения уверенного контакта с твердой поверхностью (плотный грунт, глинистая подошва), снижая негативное влияние шумов (микросейсм) от корневой системы камышей (рис. 2А, В). Группирование «СВГ-6» шестью последовательно соединенными геофонами (GS-20DX) увеличило чувствительность датчика к слабым сигналам, возбуждаемым, в слабо консолидированной толще, а его прочная конструкция и металлическая проушина, позволила извлекать маршфон из скважины, полностью заполненной водой и шламом.  Приведены основные свойства верхней части разреза (ВЧР) исследуемой площади по данным бурения с кратким описанием литологической характеристика разреза до глубины 10 м. Показаны сейсмограммы, полученные на одном участке в разных сейсмогеологических условиях. Выявлена зависимость распределения значений среднеквадратичных амплитуд и доминантных частот по площади от поверхностных условий возбуждения и приема колебаний. Данная зависимость также прослеживается на предварительных временных разрезах. Были проанализированы основные факторы, влияющие на качество получаемого сейсмического материала. На основе проведенного исследования авторами обосновывается необходимость использования комплексного подхода к анализу качества сейсмических данных при работах в сложных сейсмогеологических условиях. В качестве вывода приведены основные рекомендации к проведению сейсморазведочных работ в лиманно-плавневых зонах. The main objective of the work is the description of new technical and methodological tools used by Yuzhmorgeologiya JSC when conducting CDP 3D field seismic surveys in the estuaries of the Slavyansk district of the Krasnodar Region in 2014-2015. The main results of the experimental work are presented; the choice of survey parameters and their impact on the quality of the seismic recording is validated: digging-in of the seismic source points BOLT 2200LL-BHS, the number of excitation accumulations and the required depth of recorder sensors. Geophones “SVG-6” were used as sensors of the recorders, which were crushed with a metal pole with a fastening at the end to a depth of 1.0–2.5 m until steady contact with a solid surface (dense soil, clay base) was achieved, reducing the negative impact noise (microseism) from the root system of reeds (Fig. 2A, B). Grouping the SVG-6 with six consecutive geophones (GS-20DX) increased the sensitivity of the equipment to weak signals being excited in a weakly consolidated layer, and its robust design and metal eye, made it possible to extract the geophone from a well completely filled with water and sludge. The basic properties of the upper part of the section (near-surface section) of the studied area are given according to the drilling data with a brief description of the lithological characteristics of the section to a depth of 10 m. Seismograms obtained at one site in different seismic and geological conditions are shown. The dependence of the distribution of values of root-mean-square amplitudes and dominant frequencies over the area on the surface conditions of excitation and reception of vibrations is revealed. This dependence is also observed in the preliminary time sections. The main factors affecting the quality of the obtained seismic material were analyzed. Based on the present study, the authors validate the need for the use of an integrated approach to analyzing the quality of seismic data when working under complex seismic and geological conditions. As a conclusion, the main recommendations for seismic exploration in the estuaries are presented.

scholarly journals A cross-sectional audit of distress in patients undergoing adjuvant therapy or follow-up in central nervous system malignancies

2018 ◽  
Vol 6 (4) ◽  
pp. 305-310
Author(s):  
Vijay M Patil ◽  
Mridul Malhotra ◽  
Raees Tonse ◽  
Jayita Deodhar ◽  
Arun Chandrasekharan ◽  
...  
Keyword(s):  
Adjuvant Chemotherapy ◽  
Negative Impact ◽  
Distress Screening ◽  
Cross Sectional ◽  
Factors Affecting ◽  
Distress Score ◽  
High Distress ◽  
Cancer Network

Abstract Background Unaddressed high distress leads to noncompliance with treatment, negatively affects quality of life, and may also have a negative impact on the prognosis of cancer patients. Patients with brain tumors have higher levels of distress than the general population and hence we hypothesize that even routine visits during adjuvant treatment or follow-up are likely to be stressful. This analysis was performed to identify the incidence of distress and factors affecting it. Methods This was an audit of 84 consecutive patients seen in an adult neuro-medical oncology outpatient department who were either receiving adjuvant chemotherapy or were on follow-up. Distress screening with the National Comprehensive Cancer Network (NCCN) distress thermometer was performed. Patients in whom distress was scored as 4 or above were considered as having high distress. Descriptive statistics and logistic regression analysis were performed to identify factors affecting distress. Results The median age of the cohort was 40 years (interquartile range, 28.3 to 50 years). Actionable distress defined as a distress score of 4 or more was seen in 52 patients (61.9%, 95% CI 51.2% to 71.5%). Presence of physical deficit (odds ratio [OR] = 3.412, P = .020) and treatment under the private category (OR = 5.273, P = .003) had higher odds of having high distress. Conclusion A high proportion of brain tumor patients either on adjuvant chemotherapy or on follow-up have high distress levels that need to be addressed even during follow-up.

Transmission-based near-surface deconvolution

Geophysics ◽  
2020 ◽  
Vol 85 (2) ◽  
pp. V169-V181 ◽  
Author(s):  
Daniele Colombo ◽  
Diego Rovetta ◽  
Ernesto Sandoval-Curiel ◽  
Apostolos Kontakis
Keyword(s):  
Seismic Data ◽  
Reservoir Characterization ◽  
Complex Structure ◽  
Seismic Source ◽  
Time Lapse ◽  
Near Surface ◽  
Early Arrival ◽  
Seismic Recording ◽  
Exploration Area ◽  
Scalar Amplitude

We have developed a new framework for performing surface-consistent amplitude balancing and deconvolution of the near-surface attenuation response. Both approaches rely on the early arrival waveform of a seismic recording, which corresponds to the refracted or, more generally speaking, to the transmitted energy from a seismic source. The method adapts standard surface-consistent amplitude compensation and deconvolution to the domain of refracted/transmitted waves. A sorting domain specific for refracted energy is extended to the analysis of amplitude ratios of each trace versus a reference average trace to identify amplitude residuals that are inverted for surface consistency. The residual values are either calculated as a single scalar value for each trace or as a function of frequency to build a surface-consistent deconvolution operator. The derived operators are then applied to the data to obtain scalar amplitude balancing or amplitude balancing with spectral shaping. The derivation of the operators around the transmitted early arrival waveforms allows for deterministically decoupling the near-surface attenuation response from the remaining seismic data. The developed method is fully automatic and does not require preprocessing of the data. As such, it qualifies as a standard preprocessing tool to be applied at the early stages of seismic processing. Applications of the developed method are provided for a case in a complex, structure-controlled wadi, for a seismic time-lapse [Formula: see text] land monitoring case, and for an exploration area with high dunes and sabkhas producing large frequency-dependent anomalous amplitude responses. The new development provides an effective tool to enable better reservoir characterization and monitoring with land seismic data.

scholarly journals CHARACTERISTICS OF KEY FACTORS AFFECTING THE QUALITY OF FIXATION AND DURABILITY OF THE FUNCTIONING OF ARTIFICIAL CROWNS

2019 ◽  
Vol 7 (4) ◽  
pp. 329-335
Author(s):  
N. O. Gevkaluk ◽  
V. R. Machogan
Keyword(s):  
Dental Treatment ◽  
Negative Impact ◽  
Negative Influence ◽  
Key Factors ◽  
Factors Affecting ◽  
Periodontal Tissues ◽  
Literary Sources ◽  
Correct Ratio ◽  
Analytical Review

Introduction. Odontopreparation is an integral step in orthopedic dental treatment with non-removable orthopedic constructions. Correctly performed this stage in the treatment of artificial crowns is a guarantee of the quality of orthopedic treatment. Ensuring a stable geometry of the stump, a ledge of sufficient width on the abutment and the absence of defects on its surface, the clarity of the preparation margin and the correct ratio with marginal periodontal tissues are the most significant criteria for the quality of the intervention. In addition, the quality of the odontopreparation of the orthopedic profile is influenced by the clarity of adherence to the selected algorithm of preparation and the properties of the rotary tool used. The available literature data indicate numerous deviations in the practice of dentistry from the recommended methodology of odontopreparation, which can be explained by the relatively high frequency of complications of treatment with non-removable orthopedic structures. The purpose of the article is to analyze the key factors affecting the quality of fixation and the durability of the functioning of artificial crowns, based on an assessment of the basic principles of odontopreparation for this type of orthopedic structures and the reaction of periodontal tissues based on an analytical review of the literature. Materials and methods. The article presents the data of the literature review on the main factors that are of great importance as the fixation and durability of the functioning of artificial crowns on the stumps of dissected teeth while observing step-by-step odontopreparation algorithms with provision of proper functional and desired aesthetic requirements without negative influence on the condition of the tissue. Conclusion. Based on the analysis of literary sources, it was concluded that the key factors affecting the quality of the formation of the tooth stump to be prosthetized, subject to step-by-step odontoperational algorithms with the creation of conditions for high-quality fixation and durability of the functioning of the artificial crown, ensuring the proper functional and desired aesthetic requirements without negative impact periodontal tissues can significantly reduce the manifestation of unwanted complications, and as a result to increase the effectiveness of prosthetics with artificial crowns.

scholarly journals FACTORS OF INFLUENCE ON THE DEVELOPMENT OF HOTEL AND RESTAURANT BUSINESS IN UKRAINE

2019 ◽  
pp. 58-67
Author(s):  
Andriy Kulyk
Keyword(s):  
Negative Impact ◽  
International Markets ◽  
Tourism Industry ◽  
Quality Of Services ◽  
Factors Affecting ◽  
Business Results ◽  
Methods Of Evaluation ◽  
Tourism Services ◽  
Logical Result

Introduction. Since tourism in Ukraine in recent years has been turning into a dynamic and profitable sector of economic activity, the substantiation and search for ways to improve the quality of services in it is of particular relevance. Access to international markets for tourism services enhances interest and actualizes the study of factors affecting the quality of tourism services in Ukraine. Largely, the implementation of the task of substantiating ways to improve the quality of tourism services in general depends on the activities of the respective hotel and restaurant business institutions and their functional interaction. Methods. Empirical methods and questionnaires were used to establish and identify factors affecting the quality of services in the hotel and restaurant business. The method of abstraction and generalization was used in the study, which allowed us to draw conclusions regarding the prospects and ways to improve the quality of services in the Ukrainian hotel and restaurant business. Results. A study of the factors affecting the quality of services in the hotel and restaurant business allowed them to be classified, to identify the level of influence, to offer ways and measures to smooth out the negative and increase positive trends in this area. The development of a position on possible ways to overcome the negative impact of various factors on the quality of services in the hotel and restaurant business was the logical result of a scientific search, including through the phased implementation of measures to smooth or eliminate each of them. Discussions. The proposals worked out will make it possible to improve the quality of services in the hotel and restaurant business in Ukraine. In the future, more in-depth research is needed on how to develop the composition of hotel and restaurant services, methods of evaluation and quality control, the use of positive foreign experience on these issues, as well as finding ways to improve the use of computers and communications possible technologies in the tourism industry. Keywords: quality, service, tourism, hotel and restaurant business, tourism entities, organization, improvement.

NEW AND FUTURE DEVELOPMENTS IN SEISMIC EXPLORATION

1982 ◽  
Vol 22 (1) ◽  
pp. 200
Author(s):  
Carl H. Savit
Keyword(s):  
Seismic Reflection ◽  
Seismic Source ◽  
Velocity Estimation ◽  
Seismic Exploration ◽  
Bright Spot ◽  
S Wave ◽  
Near Surface ◽  
The Earth ◽  
Surface Materials ◽  
Receiver Arrays

Present research in reflection seismic prospecting is proceeding with three major goals.Intensive work is being done on the problem of obtaining useful reflections beneath complex near-surface materials. Such near-surface materials distort both the down-going and reflected wavefronts to an extent that deep reflections either cannot be distinguished or are so distorted as to conceal their true shapes. Current research seeks methods for obtaining enough information about near-surface irregularities to construct a model upon which to base a wavefront correction.The second major goal is to improve the resolution of the seismic reflection process. Resolution is lost because high frequencies are often weak in seismic sources and are severely attenuated by the earth, by receiver arrays, and by most processing steps. Seismic bandwidth can be increased by improving the high frequency output of the seismic source to compensate for attentuation in the earth, by reducing the size of receiver arrays, and by drastically reducing the inaccuracies of conventional processing algorithms.The third line of investigation seeks to increase the amount of information extracted from the seismic signal. The first step in this direction was the bright-spot technique, in which qualitative information on seismic reflection amplitudes was used to identify hydrocarbon deposits. Interval velocity estimation was a natural result of moving from a qualitative to a quantitative analysis of amplitudes. In theory, with a combination of P and S wave reflection data, virtually all elastic properties of subsurface rocks could be extracted from the data.In the more distant future, computers could handle complex interpretation tasks and make drilling decisions.The principal barrier to rapid implementation of virtually all of the new techniques is inadequate computer power. Despite the explosive growth of the power of computers, mainframe manufacturers have been unable to satisfy the even more rapidly increasing demands of geophysicists. Innovative processing techniques and specialized computer equipment will be essential to continuing rapid progress in geophysical exploration.

ANALYSIS AND IMPROVEMENT OF SEISMIC EXPLORATION METHODS IN EASTERN SIBERIA

2021 ◽  
pp. 56-73
Author(s):  
A. S. Еfimov ◽  
◽  
E. V. Mosyagin ◽  
Keyword(s):  
Information Content ◽  
Complex Salt ◽  
Middle Part ◽  
Thin Layers ◽  
Seismic Survey ◽  
Seismic Exploration ◽  
Eastern Siberia ◽  
Multiple Reflections ◽  
Near Surface ◽  
Surface Section

Many enterprises and authors have often addressed the problem of increasing the efficiency of seismic exploration (geological constructions and forecasting) at the prospecting stage in the Siberian Platform (SP) throughout the entire period of oil prospecting in Eastern Siberia. This is confirmed by numerous publications and production reports. Unfortunately, it should be admitted that there is still no cardinal progress in solving this problem. The reasons for the low information content of geophysical materials for the SP conditions in these publications are substantiated and set out in great detail. This is both a sharply dissected relief, and small-block models of the near-surface section, and an energy dissipation in rudaceous pyroclastic rocks of the Triassic, background of reverberation, near-surface waves formed by thin layers of traps in near-surface section, local velocity anomalies in the middle part of the section, background and interference of partially multiple reflections, complex salt tectonics, blocking and tesselation of secondary changes in Riphean rocks, forming tesselation of seismoacoustic properties. These are the main, in authors’ opinion, reasons reducing reliability of the geological section forecast based on seismic data. Some of them are removed using a complex of geophysical data. But tie, backbone on seismic horizons lies also at the heart of integration. Therefore, increasing the information content of seismic survey in regard to fixing the reflecting boundaries based on selection and substantiation, field observation systems and technologies is the most important issue in the problem under discussion.

Applicability and performance of seismic sources in clay

2021 ◽  
Author(s):  
Britta Wawerzinek ◽  
Stefan Lüth ◽  
Roman Esefelder ◽  
Rüdiger Giese ◽  
Charlotte M. Krawczyk
Keyword(s):  
Seismic Exploration ◽  
Opalinus Clay ◽  
Seismic Sources ◽  
Vibration Source ◽  
Wave Reflections ◽  
Near Surface ◽  
Geological Conditions ◽  
Reflection Imaging ◽  
And Performance ◽  
The Impact

<p><span>Since clay formations are heterogeneous and anisotropic, their seismic characterization at the meso scale is challenging. To tackle this problem, experiments using different seismic sources were undertaken in the Mont Terri Underground Rock Laboratory (URL). The first experiment was carried out using impact and vibroseis sources which were particularly designed for seismic exploration in the underground. The second experiment was conducted using an ELVIS vibration source (Polom et al. 2011) which was mainly designed for near-surface investigations on roads or in open terrain. </span></p><p><span>The first experiment focused on the applicability and performance of the modular underground system (Borm & Giese 2003) in clay. It demonstrates the successful application of impact and vibroseis source in Opalinus clay. The impact source generates signals with high signal-to-noise ratios and strong lower frequencies (above 100 Hz). Due to that, the impact source is preferred for applications at large offsets. In contrast the vibroseis source has more control of the frequency generation and is able to excite higher frequencies (up to 12 kHz) than the impact source. Therefore, the vibroseis source is preferred for high-resolution applications at near offsets. <br></span><span>Both sources are also suitable for clay characterization and reflection imaging. Travel time analyses resulted in average P- and S-wave velocities that show a clear azimuthal dependence. The carbonate-rich sandy and the sandy facies are characterized by faster velocities than the shaly facies which is stronger anisotropic than the sandy facies. Our findings are in good agreement with seismic velocities and anisotropy determined by Schuster et al. (2017), Popp & Salzer (2007) and Siegesmund et al. (2014). Although the sparse acquisition geometry was not optimal for reflection imaging of the geological conditions around the URL, later arriving shear wave reflections could be extracted from the impact data. A 3D migration focuses these reflections at a distance of ~50 m at the transition from the lower sandy facies to the upper shaly facies.</span></p><p><span>The second experiment of our pilot survey focused on seismic reflection measurements using near-surface equipment to evaluate its applicability in </span><span>URLs. Since the ELVIS source was combined with the 3-C geophones of the main experiment, the acquisition geometry was not optimal to image settings beneath the URL. The acquired ELVIS data were dominated by strong surface waves. After their removal, surface wave reflections appeared which</span><span> mainly map the structural elements of the URL. The test measurements confirmed a general applicability of ELVIS in the tunnel, however it also indicates the need to improve the acquisition geometry.</span></p>

scholarly journals Determinants of Farm Productivity in Flood Prone area: A Study in Dhemaji District of Assam

2019 ◽  
Author(s):  
Bhargab Das ◽  
Debakshi Bora
Keyword(s):  
Negative Impact ◽  
Secondary Data ◽  
Least Square ◽  
Factors Affecting ◽  
Farm Productivity ◽  
Prone Area ◽  
On Farm ◽  
The Impact ◽  
Sand Deposition

Floods have threatened the agricultural productivity in Assam every year. Quality of soil, which is one of the important factors, that determines the production and income of farm, has been damaged by flood. Various study and secondary data reveal that deposition of sand due to flood has negative impact on farm productivity. This paper tries to investigate the impact of flood induced sand deposition and other factors on farm productivity in Dhemaji district, one of the mostly flood effected area of Assam. The study is based on primary survey which included 10 flood effected villages and 276 agricultural plots for testing the quality of soil. After testing the soil quality, the paper attempts to establish the relationship between quality of soil and paddy productivity. To identify the factors affecting the productivity of the paddy and estimate the damage due to flood induced sand deposition, the study used regression models by taking productivity of paddy as dependent variable. The regression model is estimated using Ordinary Least Square (OLS) method. In order to ensure the validity of OLS results, this study also tested a Tobit model. Results of the paper revealed that sand deposition created huge damage to the paddy fields and poor agricultural outcomes from the degraded lands were forcing people to look for other livelihood and opportunities.

scholarly journals IMPACT OF CONCRETE QUALITY WORKS ON CONCRETE STRENGTH OF MONOLITHIC CONSTRUCTIONS

2020 ◽  
pp. 51-58
Author(s):  
I. Zharikov ◽  
A. Laketich ◽  
N. Laketich
Keyword(s):  
Negative Impact ◽  
Concrete Strength ◽  
Experimental Studies ◽  
Control Measures ◽  
Structural Safety ◽  
Destructive Testing ◽  
Design Strength ◽  
Near Surface ◽  
Non Destructive

the production of concrete works in the construction of monolithic frames of buildings and structures is associated with a large number of technological operations and the corresponding dependence of the quality of the products obtained from the culture of construction production and the level of its control. In many cases, concreting is carried out with some deviations from the technical regulations governing the preparation and laying of the concrete mix, which has a negative impact on the consumer characteristics of the structure, first of all, on strength. It is known that the most common methods of industrial control of the quality of concrete work are destructive tests of concrete samples laid in control cubes together with the constructed structure and non-destructive testing of concrete of the strength that has gained strength. However, even qualitatively and timely carried out control measures do not guarantee the achievement of design-controlled design strength throughout the volume, since control cubes are prepared for testing under ideal conditions of laying and concrete set of strength not observed in the design, and non-destructive methods determine the strength of near-surface layers of concrete, which allows judging reliably the strength of the material throughout the volume of the structure. Especially these circumstances relate to the most massive and, at the same time, the most important for the structural safety of the whole building frame structures – monolithic foundation slabs. The difference between the actual strength of the slabs extracted from the slab during the production of the construction and technical expertise of concrete cores depends significantly on the depth of core extraction, while the design of the slab is always carried out on the assumption of an equal strength of the concrete along the depth of the structure, which is obviously the source of the potential limited availability of foundation plates and the cause of the appearance of numerous defects in the construction and operation of structures of the above-foundation part of the frame. The paper presents experimental studies of the authors to determine the actual difference in concrete strength from the depth of foundation slabs and quantifies it.

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