Survey Work Research Articles

Computational intelligence paradigms for automata based secured energy efficient routing in wireless sensor network - A technical survey

Wireless Sensor Network (WSN) has been deployed in several areas of interest for controlling the region, automation of mundane tasks due to features such as smart sensor nodes, low cost, and small-scale factors. Earlier, the sensory units were costly and deficient in the computational and communicational capabilities which were overcome by sensing, processing, storing, and forwarding the data powered by a battery. There predominates diverse applications which affects the low-cost solutions of WSNs in numerous specialties such as observing patients in health care, target exposure, and tracking purposes, examining the atmosphere and climate, home applications, contributing protection for vehicular networks Owing to the diversity of the applications of Wireless Sensor Network, it needs to impose varying design, implementation, and performance requirements on the Wireless Sensor Network to have deep knowledge about the characteristics of WSNs. The pervasiveness of designing and optimizing WSN appeared to be a surplus to several application fields which influenced countless researchers to pay attention to several issues such as routing, mobility of nodes, coverage, and security. In recent years, designing of WSN becomes the leading domain for many researchers. A WSN is bounded with a collection of devices that are associated in the network to communicate the information collected from the field through the wireless links that have been established in the network. The data thus collected is transmitted through multiple nodes and also, the data is communicated to other networks through the gateway. During the design and deployment of WSNs, more attention is required at various levels like routing, coverage, and security. A complete system could be designed so that it could resolve the problems such as energy exhaustion, network lifetime, throughput, end-to-end time, routing, and intrusion detection could also monitor and keep control of the network environment. Therefore, this proposed technical research survey work has been carried out by devising an automaton system that can learn, monitor and control the dynamic behaviour of the network environment as well as can obtain an optimal route using Computational Intelligence Techniques. Besides, it detects the malicious activities that occur in the network using Hybrid Intrusion Detection System (IDS) model to enhance the throughput, lifetime of the network, utilization of the energy, end-to-end delay, accuracy, detection rate, computational time and recall rate.

Hurricane Kay (September 2022) Impacts Rocky Shores in the Loreto Area of Baja California Sur, Mexico

This project follows a tradition of survey work undertaken to appraise physical and biological damage in the aftermath of hurricane-strength winds and waves at a given locality where conditions were well documented prior to the arrival of a particular storm. The locality is the 12 m limestone terrace at Arroyo Blanco on the eastern shores of Isla del Carmen in Baja California Sur, Mexico. A study undertaken in February 2018 established that the surface of the terrace is covered by a coastal boulder deposit that features large slabs of limestone pealed from the outer edge by strong surf attributed to storms of hurricane intensity but unknown date. The largest slabs tend to be rectilinear in shape vulnerable to dislodgement along horizonal bedding planes and weaknesses in vertical joints. These blocks are sufficiently large and weigh enough that movement by humans without necessary mechanical equipment would be impossible. Hurricane Kay, rated as a Category 2 storm, struck the island on 8 September 2022 and an effort was made to visit the area for reconnaissance and detailed survey work soon afterwards. Although a Category 2 storm lacked the energy to remobilize the largest limestone slabs on the terrace, it was found that the storm was sufficient to disturb the adjacent seabed and redeposit as many as 44 sea fans onto the terrace by overwash; the sea fans belonged to the species Pacifigorgia adamsi. Moreover, a species of land plant common to the limestone terrace is the Gulf Star Violet (Stenotis mucronate); it suffered significant desiccation and death due to saltwater exposure. The occurrence of large potholes on the limestone terrace represents a style of physical erosion previously undocumented at the locality and rarely seen elsewhere on rocky shores.

CAGE16-5 Cruise Report: ROV-based Geological and Biological Investigations of Methane Seeps at Prins Karls Forland, Storfjordrenna Pingos and Bjørnøyrenna Craters

The cruise was an activity in of the Centre of Excellence for Gas Hydrate, Environment and Climate (CAGE) at UiT – The Arctic University of Norway. The overall aim of the cruise was to utilize the NTNU/AMOS SK30k ROV for seafloor mapping and targeted sample collection at selected CAGE sites, focusing on methane seepage areas west and south of Svalbard. More specific objectives of the cruise were to: Use an ROV-mounted multibeam system to acquire very high resolution (10cm) seabed bathymetry in areas of methane seepsConduct detailed visual seabed surveys for habitat mapping and photomosaicking at specific seep featuresCollect seabed samples of authigenic carbontate crusts, sediments, microbes, foraminifera and macro organisms associated with methane seeps from the ROV, and complimented with more traditional sampling methodsContinue time series investigations of water column measurements of methane concentrations, and of methane oxidizing microbes in the seawaterNet sampling for planktic forams at seeps Sampling activities were designed with a multi-disciplinary approach, with research groups from all CAGE work packages working together in the same locations to develop a holistic understanding of the geological, oceanographic and biological components at key methane seep sites. This cruise prioritized the acquisition of information for mapping seabed features and habitat characterizations (e.g. photomosaicking, visual information) combined with in-situ site sampling using ROV technologies, and complimented by our ‘traditional’ technologies (e.g. CTD, net, and coring devices). With these objectives in mind, the strategy for each of the selected locations is to first carry out visual survey work to acquire framework measurements and data to be of use for all groups within CAGE, followed by a consolidated sampling plan to satisfy the needs of individual researchers for sample material The cruise may be known as: CAGE16_5

A new species of planthopper in the genus Haplaxius (Hemiptera: Fulgoroidea: Cixiidae) from disturbed submontane rainforest in Jamaica

Haplaxius is a large genus of cixiid planthopper found in the New World. The genus is of particular interest due to the ability of H. crudus to transmit the phytoplasmas for lethal decline in various palm species, primarily in the Caribbean and Florida, U.S.A. During recent vector survey work in Jamaica, a specimen was collected at Castleton Botanic Garden and determined to be a new species of Haplaxius. The novel taxon is herein described, Haplaxius fornicus sp. n., and corresponding DNA sequence data is provided for the barcoding region of the cytochrome c oxidase subunit I (COI) gene, 18S rRNA gene, and histone 3 (H3) gene. An updated phylogeny of the genus is provided with currently available taxa demonstrating additional support for the placement of H. fornicus sp. n. in Haplaxius.

Handling, Processing and Composition of Cow Milk Under Two Traditional Farming Systems in Kebribeyah District of Fafan Zone, Somali Regional State, Ethiopia

The aim of this study was to assess handling, processing & chemical composition of cow milk in Kebribeyah district. The study had a survey and laboratory works. For the survey study, two production systems namely pastoral and agro-pastoral were considered. From each production system, two kebeles were selected purposively based on accessibility and potential of cow milk production. One hundred twenty households were randomly selected from purposively selected kebeles. For the laboratory part, forty samples of cow milk were analysed for chemical composition. The overall average lactation length and daily milk off-take of cow in this study were 256 days and 2.06 litres, respectively. None of the respondents washed the udder of the cow and only 6.7% of the pastoralists and 20% agro-pastoralists wash their hands before milking. Milk handling equipment were mainly plastic materials. Acacia ethaica, B. minimifolia, Blanites galabra and Solanum carense were the most commonly used smoking plant species in the area. The majority of the respondents (85.8%) produced traditional butter (Subag) and few households (10%) produced sour milk (Ciir), while very few (4.2%) households produced traditional cheese (Burcad). However, milk processing in the area is limited to wet season; when there is abundance of fodder. The average values of total solids, fat, protein, lactose and ash were 13.19%, 4.67%, 3.45%, 5.18% and 0.72%, respectively. However, significance differences (P<0.05) were found between pastoral and ago-pastoral production systems in terms of total solids, fat, and protein. The chemical properties of milk samples obtained from pastoral and agro-pastoral areas were within the acceptable standard levels settled by different scholars. In general, milk producers should also be supported with strong extension service by way of introducing improved dairy technologies, improved milk handling and processing equipments. Furthermore, there is a need for further investigations on composition with various farming systems.

Survey on Exact kNN Queries over High-Dimensional Data Space.

k nearest neighbours (kNN) queries are fundamental in many applications, ranging from data mining, recommendation system and Internet of Things, to Industry 4.0 framework applications. In mining, specifically, it can be used for the classification of human activities, iterative closest point registration and pattern recognition and has also been helpful for intrusion detection systems and fault detection. Due to the importance of kNN queries, many algorithms have been proposed in the literature, for both static and dynamic data. In this paper, we focus on exact kNN queries and present a comprehensive survey of exact kNN queries. In particular, we study two fundamental types of exact kNN queries: the kNN Search queries and the kNN Join queries. Our survey focuses on exact approaches over high-dimensional data space, which covers 20 kNN Search methods and 9 kNN Join methods. To the best of our knowledge, this is the first work of a comprehensive survey of exact kNN queries over high-dimensional datasets. We specifically categorise the algorithms based on indexing strategies, data and space partitioning strategies, clustering techniques and the computing paradigm. We provide useful insights for the evolution of approaches based on the various categorisation factors, as well as the possibility of further expansion. Lastly, we discuss some open challenges and future research directions.

INFILTRATION AND COLMATATION DYNAMICS ON PHYSICAL MODELS STUDY BY INFILTRATION BASINS AT ARTIFICIAL GROUNDWATER RECHARGE

The problem of the growing shortage of water resources in the world, including in the territory of South-East Kazakhstan, due to global warming and aggravated by long distances to natural sources of good quality water, requires the combined use of surface water and groundwater from local aquifers to supply the local population with high-quality drinking water. The application of methods of artificial groundwater spreading can be an effective way only if positive characteristics of soil and soil parameters of the aeration zone and productive aquifers are obtained in the processes of infiltration and colmatation, which are one of the decisive indicators for ensuring productivity and duration of operation of infiltration basins in the given mode. This work presents the main results of complex field studies of the processes of infiltration and colmatation in infiltration mini-basins at pilot sites within the Aksu, Lepsy and Koksu river valleys, taken as typical for the territory of South-Eastern Kazakhstan, which most needs to increase the water supply of rural population settlements and remote pastures. These studies were supplemented by a detailed assessment of the water-physical, hydrodynamic and filtration properties of the overburden and the upper layers of the aquifer. The new data showed that the infiltration rate varied from 15 m/day at the beginning to 0.75 m/day at the end and remained practically unchanged by the end of the experiment. This was largely facilitated by the values of the heterogeneity coefficient of the granulometric composition of all the examined soils obtained during the studies, which did not exceed 3.0 due to the uniform distribution of coarse fractions and a small proportion of loams and sandy loams. Approximately one month after the start of the tests, a colmatation layer began to be generated at the bottom of the mini-ponds, the thickness of which by the end of the test reached from 3 mm for clay silt to 6 mm for silty clay. However, as studies have shown, the generation of a colmatation layer due to the settling of suspended particles of surface water did not significantly impact on the infiltration processes, as evidenced by the rated values of specific flow rates, which in the final period of time ranged from 0.86 to 0.75-0.80 m3/day per square meter of reduced infiltration surface. Thus, the generated positive results of field studies can serve as a factual basis for design, and can also be recommended and accepted as design indicators both at the stage of a feasibility study and at the stage of detailed design of artificial groundwater spreading systems without additional labor-intensive and costly survey works, and the approved methodology for their implementation will be useful when conducting similar studies in other regions.

GIS AND GPS-BASED MAPPING OF SOIL PROPERTIES IN SUGARCANE GROWING AREAS OF SNJ SUGAR FACTORY ZONE, ANDHRA PRADESH

A survey work was conducted to assess the soil fertility status of sugarcane growing soils of SNJ sugar factory zone, Andhra Pradesh. Two hundred seventeen (217) soil samples were collected at a depth of 0-15 cm from nine mandals (Palasamudram, Veduru Kuppam, Penumuru, Rompicherla, Pileru, Pulicherla, Chinnagottigallu, Erravaripalem and Chandragiri) and analyzed for physicochemical and chemical properties. Geo reference coordinates (Latitude and Longitude) also noted at sampling sites. The results revealed that 38% of soils were neutral in reaction (pH 6.5-7.0), 10% were slightly acidic and 33% of soils were slightly alkaline in reaction. All soils had non saline nature. 80% of soils were low in organic carbon (OC) content and 20% of soils had medium in OC content. Available nitrogen in 93% of collected soils was low (< 280 kg ha-1). Available phosphorus in these sugarcane growing soils ranged from 26 to 114 kg ha-1 with a mean of 57.07 kg ha-1. Available potassium levels varied between 197 and 521 kg ha-1 (medium to high) with a mean of 347 kg ha-1. The soils have available sulphur ranged from 2.6 to 15.6 mg kg-1. 74% of soils were showed deficient in available sulphur. Digital soil maps for pH, EC, OC, available nitrogen, phosphorus, potassium and sulphur prepared by using GIS approach. Soil nutrient index for OC, available nitrogen, phosphorus, potassium and sulphur was 1, 1, 2, 2.31 and 1, respectively

Трансполярная магистраль в освоении северо-западной части Западной Сибири (к 75-летию с начала строительства)

The article is based on the materials identified in seven collections of archives of Tyumen Oblast, the use of a number of published documents, the memoirs of the prospector Aleksandr Pobozhiy. The aim of the work is to show the extremely important significance of the Transpolar Railway in various areas of territory development. In connection with this aim, the main research attention is focused on the influence of the railway, which had different names in different periods of time (Vorkuta-Salekhard, Polar Railway, Chum-Salekhard-Igarka), on the economic development of the region. The influence was manifested both during the construction period and after its completion. The author used historical genetic and historical comparative research methods. The historical genetic method was used for the analysis of the causes of the phenomena that developed during the construction period, including the reasons for the termination of the railway's construction. The historical comparative method was used for the general analysis of the processes that developed in the north of Tyumen Oblast. These processes were considered in the context of the territory's economic development. The phenomena in the Arctic zones of the region in the conditions of modern and previous stages of development were compared. The author's main conclusions are the following. The Transpolar Railway entailed a large-scale scientific study of the vast territory of Yamalo-Nenets National Okrug, caused the development of railway, aviation, sea, river transport and transport communications with the center of the country; influenced the growth of the population and its qualitative characteristics. The built telephone and telegraph line provided stable communication with different regions of the country. Regarding the reasons for the termination of the construction of the road, the author came to the conclusion that they were related to the geological features of the section connecting the right and left wings of the railway - the Nadym-Pur-Taz interfluve. The features of this site led to the need for construction conservation. Due to the peculiar political processes in the country (the consequences of Stalin's death, Beria's execution, the liquidation of the GULAG system), the construction was transferred from the conservation stage to the completion stage. The launched study of the features of the territory of the Nadym-Pur-Taz interfluve prepared the main result of the design and survey work on the railway, which consisted in the transition to its geological study. The author also came to the conclusion that, without making it public, the road was used in the geological, gas, transport, urban development of the territory of Yamalo-Nenets Okrug.

About the choice of the test method to clarify the actual working scheme of the beam

This article discusses the problem of determining the actual scheme of a precast reinforced concrete frame of a building when performing engineering surveys. The method of connecting precast reinforced concrete structures in industrial buildings with heavy equipment plays an important role in assessing the stress state of building structures. It is not always possible to perform the opening of nodes in the conditions of existing production, since this requires stopping technological processes or dismantling equipment. The article discusses the possibilities of static and dynamic tests for the study of support units in precast reinforced concrete structures during engineering surveys. The possibilities of static and dynamic test methods are considered, as well as the advantages and disadvantages of these methods when evaluating support units in precast reinforced concrete structures of buildings and structures during surveys. As an example for the study, the case of determining the current structural scheme of a precast reinforced concrete floor using dynamic tests is considered. The article analyzes previous studies on the use of the dynamic method in determining the actual scheme of existing reinforced concrete structures of an industrial building. The results of theoretical studies and their comparison with experimental results are presented. The general conclusions based on the results of the study are formulated, and recommendations are given on the choice of a method of testing structures for cases of establishing a structural scheme of precast reinforced concrete crossbars in operated industrial buildings during survey work.

Геологические исследования вдоль Кругобайкальской железной дороги, выполненные в конце XIX–начале XX вв.

The survey work, construction and operation of the railroad from Irkutsk along the southern shore of Lake Baikal were accompanied by detailed geological studies. During several field seasons during the surveys all projected directions of the railroad were studied. As a result, it was recommended to build a railroad from the source of Angara to Mysovoye village along the shore of Lake Baikal. But the results turned out to be too optimistic. During the development of rocky slopes from the source of Angara to Kultuk, intensive rockfalls began, which continued during the operation of the line, which caused new surveys of the entire section. In the vicinity of Mysovoye village, the identified ancient landslides caused additional study of the geological structure of the area and drainage works.

Analysis of Tsunami Traveling Ionospheric Disturbances Due to Tsunami Using The GNSS-TEC Method

The Global Navigation Satellite System (GNSS) is a navigation satellite system that provides information on the position and speed of 3D objects on the earth’s surface. GNSS is increasingly being used in the field of survey and mapping work because of its high measurement accuracy, and its use can be done anywhere and anytime. The working principle of GNSS is to transmit digital data from satellites to receivers on the earth’s surface. The digital data is carried by a carrier microwave called the L-band. In the propagation path, the carrier microwave will pass through the ionosphere and troposphere. The collection of electrons contained in the ionosphere layer and the wet & dry components in the troposphere can disrupt the wave propagation path to be slower. This slow propagation will cause the accuracy of the results obtained during the measurement to be more inaccurate. The delayed wave data can obtain the Total Electron Content (TEC) value in the ionosphere layer. TEC is a value that represents the electron density in 1m2 in the ionosphere. The vertical movement of the land surface and seawater can suddenly cause acoustic waves that propagate towards the ionosphere layer, which causes the electron density to decompose. These disorders are known as Traveling Ionospheric Disturbances (TID). In this study, we studied the characteristics of the change in electron density in the ionosphere caused by the tsunami. The tsunami observed was a tsunami in the territory of Indonesia due to the eruption of Mount Tonga on January 15, 2022. The change in electron density was calculated from the significant difference in the TEC value during the tsunami propagation time. The calculation of the change in the TEC value is called the TEC reduction. TEC reduction is obtained by calculating the TEC value, calculated with the reference value of the polynomial curve. The result of the TEC reduction, which has a change in value at the same time as the tsunami is coming, is most likely the TID of the tsunami.

Ocena wpływu budowy obwodnicy miasta Tomaszowa Lubelskiego na strukturę przestrzenną obszarów wiejskich

In recent years, the road network in Poland has undergone significant development, meeting the objective of creating a coherent network of roads to ensure the efficient functioning of passenger and freight transport. Linear investments, such as the construction of motorways, expressways or bypasses, are an important element that improves the safety and comfort of the life of residents, and has a significant impact on the economic and regional progress. In addition to the undoubted benefits of constructing a bypass, its possible negative impact on the surrounding agricultural and forest areas should be emphasised. Poor planning and construction of the bypass itself, without prior programming of survey and management works, can lead to disturbances in the spatial structure of neighbouring villages. This study attempts to analyse and evaluate the impact of the construction of the Tomaszów Lubelski bypass on the spatial structure of rural areas located in the eastern part of Tomaszów County (Lubelskie Voivodeship), which is a 9.58 km long section of the S17 Warsaw – Hrebenne expressway. The study undertook a detailed analysis of only those factors that adversely affect the spatial structure of rural areas. On the basis of research on the subject, factors affecting and significantly changing the spatial structure of rural areas were identified, which allowed to formulate final conclusions regarding the problem of realising linear investments in relation to shaping the space of rural areas.

Sedimentation and its effect on storage capacity in Naghlu reservoir

The Naghlu reservoir has been studied to determine the level of siltation and sedimentation characteristics in the reservoir bed. The study was fulfilled in two phases, i.e., field survey and laboratory work for determining the level of siltation and carrying out the grain size analyses of the collected sediment samples at 34 locations representing the whole reservoir area. The Naghlu Dam is a gravity dam which has been built to generate electricity. The dam was built on the Kabul River. Two main tributaries of the Kabul River, i.e., the Kabul and the Panjshir, feed the reservoir. The catchment area of Kabul and Panjshir tributaries feeding the Naghlu reservoir is around 26,000 km2. The reservoir’s surface area is around 15.5 square kilometers, and the volume is 550 million m3 at the normal operation level; the useful volume of the reservoir is around 380 million m3. Dam provides 100 MW of electricity for the surrounding areas, including Kabul and Jalalabad.

СОВЕРШЕНСТВОВАНИЕ МЕТОДИКИ ИСПОЛЬЗОВАНИЯ БПЛА В ИНЖЕНЕРНО- ГЕОЛОГИЧЕСКИХ ИЗЫСКАНИЯХ И ЕГО ЭКОНОМИЧЕСКОГО ОБОСНОВАНИЯ

In today’s world, where technology is developing at incredible speed, the company’s success largely depends on its ability to adapt to new conditions and use innovative approaches in its activities. One of these approaches is the introduction of new metodic and technologies that can significantly increase the efficiency of the company and bring it to a new level of development. An alternative type of shooting from unmanned aerial vehicles (UAVs) is becoming very effective. This is due to the low cost of drilling and the high automation and productivity of field work, which is achieved by creating a three-dimensional model and automated decryption of the territory. In this study, a technique has been proposed that allows decryption of elements using several orthophofuels made from different angles. The implementation of this methodology showed an increase in the quality of decryption, a reduction in labor and time costs, which ultimately had a positive effect on design, survey and construction work.

Оценка состояния подземных инженерных сооружений мелиоративной системы с помощью карт влажности, полученных на основе данных дистанционного зондирования земли беспилотным летательным аппаратом DJI Phantom 4 Multispectra

Reclamation system is a complex of engineering structures and devices that ensure the creation of the required water, air, thermal and nutrient regimes of soils. The composition of reclamation systems includes underground pipelines, drains, hydraulic structures that may fail and require repair, but it is impossible to detect a problem area without monitoring the area of the system by antediluvian methods or conducting survey work. The purpose of the work: to justify the use of soil moisture maps obtained by the DJI PHANTOM 4 MULTISPECTRA UAV to identify problem areas of the reclamation network or vice versa absence. Aerial photography was carried out in May 2021 on the treated section of the drainage and humidification network of the Yakhrom floodplain of the Moscow region. As a result of the survey, a digital relief model, an operational humidity map based on the calculated NDWI water index were obtained. The flight altitude of the quadcopter was 180 m above the earth’s surface, the pixel size of the image of the earth’s surface to be 7.9 cm. According to the results of aerial photography on the selected site, the absolute marks of the earth’s surface vary from 134.67 to 135.23. On average, the slope of the earth’s surface of the selected site is 0.002 in the direction from northwest to southeast. There are no pronounced microforms of relief moisture in the surface layer of the soil obtained in the field corresponds to the variety of color areas of the NDWI water indices highlighted on the operational humidity map. In the soil conditions of the studied area, the moisture content of the surface soil layer is logarithmic with the normalized difference water index NDWI. The correlation coefficient is 0.9 ± 0.06, which indicates a very high relationship between the studied indicators. Such a map can be used to identify problem areas of the reclamation network.

РЕТРОСПЕКТИВНЫЙ АНАЛИЗ ИХТИОФАУНЫ РЕКИ ТОМЬ В ПРЕДДВЕРИИ СТРОИТЕЛЬСТВА КРАПИВИНСКОГО ВОДОХРАНИЛИЩА

The resumption of design and survey work for the construction of the Krapivinsky Hydroelectric Power Plant on the Tom River has necessitated the assessment of the current state of its fish resources and called for making the prediction of their transformation in the event of the hydroelectric complex being put into operation. In the early 20th century, the Tom River was classified as a salmonid habitat. At that time, such valuable commercial species as the Siberian taimen Hucho taimen, blunt-snouted lenok Brachymystax tumensis , tugun Coregonus tugun, humpback whitefish Coregonus pidschian, Nickolsky’s grayling Thymallus nikolskyi , nelma Stenodus leucichthys nelma, muksun Coregonus muksun, and peled Coregonus peled were permanent residents. Sturgeons, such as the Siberian sturgeon Acipenser baerii and sterlet Acipenser ruthenus, were also abundant. Currently, out of these species, grayling, occasionally taimen and lenok are caught in the Tom River; the common roach Rutilus rutilus , European perch Perca fluviatilis, Siberian dace Leuciscus baicalensis and Eurasian ruffe Gymnocephalus cernuus comprise 95 % of all fish caught. If construction of the Krapivinsky Reservoir on the Tom River is completed and it is put into operation, a deep-water, slow-flowing “lake-type” water body will be created. The river bed will be blocked, so semi-anadromous fish species, many of which are listed in the Red Data Book-such as Siberian sturgeon, sterlet and nelma,-will disappear. A decrease in the abundance of grayling, taimen and lenok, already low in number, should also be expected. These fish species winter in the pits, some of them migrate to the Ob River, so, after passing the spillway, they will not be able to return upstream to the spawning grounds. The abundance of lake and lake-river species is expected to increase, among them the common roach, dace Leuciscus leuciscus , European perch, Prussian carp Carassius gibelio (introduced locally, subsequently self-dispersed), as well as common bleak Alburnus alburnus and sunbleak Leucaspius delineates (accidental invaders). In the future, it is possible to make an attempt to introduce peled to the upper basin of the Krapivinsky Reservoir. There is a prospective threat of the Chinese sleeper Perccottus glenii spreading in the upcoming reservoir, which can severely undermine its fish stocks.

Исследования геолога А.В. Львова на Кругобайкальской железной дороге

The article deals with the activities of geologist A.V. Lvov during the survey work of the Circum-Baikal railroad and at the beginning of operation of the Transbaikal railroad. A detailed survey of the outcrops formed during the construction of the railroad made it possible to refute the previously proposed conclusions of mining engineers and to give detailed recommendations on the protection of the railroad bed from rockfalls, both during construction and at the beginning of the operation of the railroad. Along with geological studies, work was done to determine the sources of water inflow into the most problematic tunnel on the railroad.

Performance evaluation of single and double-frequency low-cost GNSS receivers in static relative mode

The advancement of low-cost GNSS receivers with modern built-up characteristics has opened a new window to investigate the performance of various low-cost receivers with an outlook on their performance and suitability for varied geodetic purposes. The main objective of this study is to evaluate the positioning performance of single and double-frequency GNSS receivers in combination with geodetic antennas in static relative mode regarding Mexican regulations. The recorded observations were processed by a static relative method including the CORS station from the National Institute of Statistics and Geography in Mexico (INEGI). The results of the survey conducted at a distance of 4 and 33 km from CORS station show similar accuracy for all low-cost receivers. For low-cost GNSS receivers NEO-M8T, NEO-6T, and ZED-F9P the solutions that were obtained reached mm in horizontal precision using a geodetic grade antenna. Similarly, the ZED-F9P model was proved at a long distance from the CORS station and presents high precision. Regarding the vertical component, in all cases where the GGM10 model was included, the vertical component is not allowed to use for topography or geodetic works, however, the horizontal component where mm precision was achieved is allowed for different highly precision survey works.

Choice of land for linear and area objects of oilfield construction

The article discusses the work process on the selection of land plots for oilfield construction. The paper also describes the sequence of survey work necessary for approval the best variants of construction.