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Self-localization and pose registration are required for sound operation of next generation autonomous vehicles under uncertain environments. Thus, precise localization and mapping are crucial tasks in odometry, planning and other downstream processing. In order to reduce information loss in preprocessing, we propose leveraging LiDAR-based localization and mapping (LOAM) with point cloud-based deep learning instead of convolutional neural network (CNN) based methods that require cylindrical projection. The normal distribution transform (NDT) algorithm is then used to refine the former coarse pose estimation from the deep learning model. The results demonstrate that the proposed method is comparable in performance to recent benchmark studies. We also explore the possibility of using Product Quantization to improve NDT internal neighborhood searching by using high-level features as fingerprints.

Plants respond to their environment through adaptations; for example, earthworms that create heterogeneity can lead to local adaptation of roots. This research identifies a mechanism to explain plant responses to earthworms and how these mechanisms are related. Our results show that tillage intensity has a negative effect on earthworms and root volume. The mean root volume and earthworm biomass under conventional tillage were lower than in reduced tillage and no-tillage. The root volume and the root diameter in the field with residues were higher than in the field without residues, while the root length density and earthworm biomass in the field with residues were lower than in the field without residues. This study demonstrates that the mean of the root length density and biomass of the earthworms were higher in sandy loam than in loam. Therefore, sand content had a positive effect on root length density (R2 = 0.72, p < 0.01) and earthworm biomass (R2 = 0.74, p < 0.01). Earthworm biomass had a positive effect on root volume (R2 = 0.54, p < 0.05) and length density (R2 = 0.88, p < 0.01). This confirms our hypothesis on the effect of earthworms on root systems.

The purpose of this work was to investigate the effect of the burning environment on the properties and phase composition of clinker-based ceramic specimens made from loam with diatomite and bentonite clay in order to develop technological parameters for the manufacture of clinker products. The main raw material used for the experiments was local fusible loam from the Almaty deposit, which is the basis for the production of 75 and 100 grade ceramic bricks. Diatomite from Utesai deposit (Aktobe region) and highly plastic bentonite clay from Darbazin deposit (Turkestan region) were used as additives. Loam and bentonite clay were applied after grinding and sieving through a 1 mm sieve. Diatomite was applied after grinding and milling until it had completely passed through a 0.315 mm sieve. The raw materials are mixed after dosing, and then water is added in the amount required until a pliable mass is obtained. To investigate the properties of the products, standard cylinder samples were prepared with a diameter of 50 mm and a height of 50 mm. The cylinder samples were pressed on a hydraulic press at a pressure of 2–4 kN. The samples were dried in a desiccator at 95–100 °C for 2 h. After drying, the products were burning in a muffle kiln. The analysis of the properties of the burned products showed that the optimum ratio in the ceramic mixture of loam and diatomite to loam and bentonite clay is 85%:15%. After burning in a slightly oxidising environment at 1170 °C, the ceramic specimens correspond to Class 2 for the medium-density and compressive strength grades M 400 and M 500 (GOST 530-2012 (Government standard). X-ray diffractometric analysis showed that the products contain augite, quartz and anorthite as crystalline phases, with the former predominating. After burning in a reducing atmosphere, at 1170 °C, the properties of the samples have higher values compared to the samples burning in a weakly oxidising atmosphere. The resulting properties, according to the regulations, are characteristic of clinker bricks (DIN V 105-1 (technical requirements for clinker façade bricks). After burning in a reducing environment, the phase composition of the products changes qualitatively; in addition to augite and quartz, albite, diopside, orthoclase and haematite are present in the samples.

The relevance of the work is due to the need to expand the raw material base of the construction industry and develop an effective technology for the disposal of waste from water treatment plants. The purpose of the work was to establish the features of the phase composition and structure of loam ceramics and incinerated sewage sludge ash. The work used differential thermal and X-ray phase analysis, electron microscopy. It has been established that the enrichment of loam by the addition of ash from the incineration of domestic sewage sludge (DSS) ensures the connection of aggregates and individual particles into a single system reinforced with anorthite crystals. In this case, an increase in the amount of the anorthite phase and the mechanical strength of ceramics occurs with an increase in the proportion of ash from the incineration of DSS in the charge to more than 20 %. It is shown that the structure of ceramics made from loam with the addition of ash from the combustion of DSS is characterized by a spatial frame, which is a kind of a matrix that combines filler particles according to the "core-shell" type, and an increase in the number of reserve pores, which favorably affects the frost resistance of ceramics.

Agricultural environment mapping is the premise of the autonomous navigation of agricultural robots. Due to the undulating terrain and chaotic environment, it is challenging to accurately map the environmental maize field using existing LOAM (LiDAR odometry and mapping) methods. This paper proposes a LOAM method based on maize stalk semantic features for 6-DOF (degrees of freedom) pose estimation and field mapping with agricultural robots operating in a dynamic environment. The piecewise plane fitting method filters the ground points for the complex farmland terrain. To eliminate the unstable factors in the environment, we introduce the semantic information of maize plants into the feature extraction. The regional growth method segments the maize stalk instances, the instances are parameterized to a line model, and the optimization method calculates the pose transformation. Finally, the mapping method corrects the drift error of the odometry and outputs the maize field map. This paper compares our method with the GICP and LOAM methods. The trajectory relative errors of our method are 0.88%, 0.96%, and 2.12%, respectively, better than other methods. At the same time, the map drawn by our method has less ghosting and clearer plant edges. The results show that our method is more robust and accurate than other methods due to the introduction of semantic information in the environment. The mapping of corn fields can be further used in precision agriculture.

Experimental research of weak bases reinforced by vertical soil-cement elements are discribed in this article. Tray research of weak clay bases and bases with percent of reinforcement from 2,1% to 7,1% under strip stamp were conduct. As a result of the experiment settlements for each of soil base models were obtained. Characteristic curves of the influence of the reinforcement percentage on the bearing capacity, deformability are given, character of settlements of the investigated soil mass in time at step-increasing loading are shown. It was found that depending on the percentage of reinforcement the critical pressures increased linearly and the values of settlement at critical pressures were determined increased with the base reinforcement percentage. Empirical dependencies were obtained to determine the critical pressures depending on the percentage of reinforcement for the investigated soil conditions. In conclusion, the effectiveness of reinforcing the base of the strip foundations by vertical soil-cement elements was proved.

Disease complex of carrot (Daucus carota L.) involving root knot nematode Meloidogyne incognita and two fungi Alternaria dauci and Rhizoctonia solani were studied in three soil types. More plant growth, chlorophyll, carotenoid and proline contents were found in carrot grown in fly ash mix soil than plants grown in sand mix soil and loamy soil. Inoculation of M. incognita, R. solani, and A. dauci reduced plant growth, chlorophyll and carotenoid but increased proline contents. Inoculation of M. incognita 20 days prior to a fungal pathogen caused a greater reduction in plant growth, chlorophyll and carotenoid than fungal pathogen was inoculated prior. Inoculation of A. dauci prior to R. solani or vice versa had a similar effect on plant growth, chlorophyll, and carotenoid. Nematode multiplication and galling was higher in plants grown in sand mix soil followed by loamy soil and fly ash mix soil. Both fungi had adverse effects on galling and nematode multiplication. Blight disease index caused by A. dauci was 3 and crown rot index by R. solani was also recorded 3. These disease indices were 5 when pathogens were inoculated in combinations.

A comparative agronomical experiment was conducted at research station/ Department of Horticulture and Landscape/ College of Agriculture/ Tikrit University, to study the effect of two different soil textures (loam and silt loam) on growth and yield of six varieties of okra. The two soil textures were analyzed for pH, nitrogen, organic matter, phosphorous, Ca, K, Mg etc. at the Central Laboratory of Soil Science and Water Resource Department, College of Agriculture, Tikrit University. Six okra varieties of okra were used in this experiment (i. e., Clamson, Hussainawia, Sultani, Btra, Clemson and Clemson spinless). The experiment was carried out with a Randomized Complete Block Design with Split plot arrangement with four replicates. Data were recorded for plant height, stem diameter, branches number on main stem, total number of branches, pod length, pod diameter, pod weight, pods number, yield per plant and percentage of dry matter in pod. Results indicated that plant height, branches number on main stem, pod weight, pod number and yield per plant produced in Loam soil were significantly higher (P ≤ 0.05) than those produced in Silt loam soil. Irrespective of soil texture, the stem diameter, branches number on main stem and total branches produced in Btra variety, whereas, pod diameter, pod weight, pod number and pod yield per plant produced in Hussainawia variety were significantly higher (P ≤ 0.05) than those produced in other varieties. But, pod length did not differ significantly (P ≤ 0.05) between six varieties. It can be concluded from the present findings that Btra and Hussainawia cultivars may be produced in different soil..

This study aimed to identify the composition of ceramic mass for the manufacture of bricks with improved properties based on local loam using diatomite and bentonite clay. For the experiments, loam from the Almaty deposit (Kazakhstan) was applied as the primary product, and used for the production of ceramic bricks with grades of 75 and 100. Diatomite from the Zhalpak and Utesai deposits and highly plastic bentonite clay from the Darbazin deposit (Kazakhstan) were used as additives. An analysis of the properties of the burned products demonstrated that supplementation with diatomite and bentonite in the loam lowers the average density and increases the compressive strength of samples burned at 1000 and 1100 °C. Herewith, the optimal amount of diatomite and bentonite clay to add is 15%, with a fractional composition of 0.315–0.16 mm and less than 1 mm, respectively. It was established that the optimal additions of diatomite and bentonite clay to loam make it possible to obtain after burning at 1170 °C samples of ceramic products corresponding to the 2nd class in terms of the average density and compressive strength grades M 400 and M 500.

Domestication of biennial Lepidium campestre L. offers possibilities for more varied crop rotations in cold regions, with increased crop cover during winter. In the first winter after sowing, L. campestre can reduce nitrogen (N) leaching before harvesting in the second year. In this system no soil tillage is needed during the first year, unlike in systems with annual crops. A three-year leaching study on loam soil in southern Sweden revealed significantly (p

Walls of wet loam, used in earthen houses, generally experience more shrinkage which results in cracks and less compressive strength. This paper presents a technique of producing loam masonry blocks that are compacted in drained state during casting process in order to minimize shrinkage. For this purpose, loam masonry blocks were cast and compacted at a pressure of 6 MPa and then dried in shade by covering them in plastic sheet. The results show that linear shrinkage of 2% occurred which is smaller when compared to un-compacted wet loam walls. This implies that the loam masonry blocks compacted in drained state is expected to perform better than un-compacted wet loam walls.

The problem of developing a new generalized strength (plasticity)condition is applied to soils of anisotropic, in particular a transversal - isotropic (trans - structural) structure. This condition is derived by generalizing the known Coulomb - Moore plasticity condition σc for two directions: along the layers parallel and crosswise to layers, that is, for the perpendicular directions to the layers, relative to the isotropy plane for the transtropic soil, systematized for the first time by A.K. Bugrov and A.I. Golubev. It is proposed to analyze the possibility of generalizing the conditions of plasticity (strength) in the principal stresses σ1 and σ2, as well as on the values of the critical principal stress σ1c and σ2c, proposed and developed in due time for soils of the isotropic structure N.A. Tsytovich and N.S. Bulychev. Following the approach of W. Witke, who proposed to apply such a criterion to rocks of an orthotropic structure, the formulated criterion is proposed, which allows to determine the moment of the onset of plastic destruction of anisotropic soil and the direction of its further spread from the initial point. The table contains critical values of anisotropic soil in two orthogonal directions of the coordinate axes, calculated with the help of the proposed new criterion, which allows us to solve a new class of problems of fracture mechanics.

The effect of nanosized additives on the strength properties of ceramics based on fusible brick loam of the Klyuchischenskoye deposit has been studied. In general, all nanosized additives selected for the study had a positive effect on the strength properties of ceramics. The greatest increase in strength, when using nanosized silica ash Laksil 30, was 70 %, in relation to the control sample. When using silica ash, an increase in the content of the amorphous phase in the shard after firing is noted against the background of a decrease in its porosity, which causes an increase in strength characteristics. The nature of the destruction of the samples also differed. The destruction of the control sample was accompanied by the formation and gradual opening of cracks. The destruction of the modified samples was more fragile in comparison with the control. Thus, the effectiveness of nanosized additives on the strength properties of ceramics is shown.

Because of the potential threat for development of plants, resulting from the occurrence of too high cobalt contents in soil environment, a study was undertaken aiming to determine the effect of increasing soil contamination with cobalt (0, 20, 40, 80, 160, 320 mg · kg-¹ of soil), following the application of neutralising substances (farmyard manure, loam, charcoal, zeolite and calcium oxide), on the soil pH, hydrolytic acidity, total exchangeable bases, cation exchange capacity and the base saturation. In the series without neutralising substances added, soil contamination with the highest doses of cobalt resulted in a decrease in pH, in the total exchangeable bases, in the cation exchange capacity, and in the base saturation, and in an increase in the soil hydrolytic acidity. Of the applied neutralising substances, farmyard manure and particular calcium oxide had the greatest effect on the analysed soil properties. The application of the substances resulted in an increase in the soil pH, in the base exchange capacity, in the cation exchange capacity and in the base saturation and also in a decrease in the soil hydrolytic acidity. The other substances had no, or a small, effect on the studied soil properties.

The effects of different temperatures (20 °C, 25 °C, 30 °C, 35 °C and photoperiod 26 °C/21 °C), types of soil (sand and loam) and soil herbicides (oxyfluorfen, terbuthylazine and mesotrione) on seed germination percentage, germination rate, as well as seedling length and weight of common milkweed (Asclepias syriaca L.) were examined. Over a period of ten days, germinated seeds were counted daily, and seedling length and weight were measured on the final day and germination rate calculated. The results indicated that temperature was the factor that significantly affected the percentage of germinated seeds of common milkweed, seedling length and germination rate, while it had less influence on seedling weight. The results showed that the alternating day/night temperature of 26 °C/21 °C also had a significant impact as the percentage of germinated seeds was the highest at that temperature on both soil types (sand: 71.3%; loam: 61.3%). Data regarding the herbicides tested (oxyfluorfen, terbuthylazine and mesotrione) showed decreasing germination percentage and seedling length with increasing herbicide concentrations on both soil types. Their effect was weakest on seedling weight. Tested herbicides are usable in control of common milkweed at the stages of germination and early establishment.

Currently, a worldwide dynamic rise of interest in using soil as a construction material can be observed. This trend is evident in the rapid rise of the amount of standards that deal with soil techniques. In 2012 the number of standards was larger by one third than five years prior. To create a full standardization of the rammed earth technique it is necessary to take into account the diversity of used soil and stabilizing additives. The proportion of the components, the process of element production and the research methods must also be made uniform. The article describes the results of research on the compressive strength of rammed earth samples that differed from each other with regards to the type of loam used for the mixture and the amount of the stabilizer. The stabilizer used was Portland cement CEM I 42.5R. The research and the analysis of the results were based on foreign publications, the New Zealand standard NZS 4298:1998, the American Standard NMAC14.7.4 and archival Polish Standards from the 1960’s that dealt with earth material.

Sorption-desorption processes govern the movement of all chemicals including pesticides in soils. The present investigation was undertaken to study the sorption-desorption of imidacloprid, using a batch method, on soils of five different location of India. Sorption data were fitted to Freundlich isotherm. The log K value was the highest for loam type soil (1.830) and the lowest for clay type soil (1.661). The value of 1/n was the maximum for silt loam soil (0.909) but minimum for loam soil (0.723). Simple correlation analysis indicated that among soil properties only electrical conductivity showed a higher but marginally non-significant negative correlation with log K (r = -0.826) indicating that higher concentration of solutes solutes are conducive to low sorption capacity of soil. The desorption data conformed to two surfaces Freundlich desorption isotherm. The values of 1/n1' corresponding to easily desorbed fraction of imidacloprid showed significant negative correlation with soil pH (r = -0.886, significant at p ≤0.05) but significant positive correlation with clay content (r = 0.980, significant at p ≤0.01). The desorption index for easily desorbed fraction of imidacloprid (n1’/n) also had significant negative correlation with soil pH (r = 0.953, significant at p ≤0.05). From cumulative desorption data, it appeared that bioavailability of imidacloprid would be lower in neutral soil than acidic or alkaline soils.

For the research of irrigation optimization and nitrate leaching it is important to know the short-term soil moisture variation during percolation episodes as well as its seasonal pattern. Dielectric soil moisture sensors Virrib (AMET - Consortium) and ThetaProbe ML2x (Delta-T) were used for this purpose over several years for measuring soil moisture content at hourly intervals in Valečov (49°38'40" N, 14°30'25" E, 461 m a.s.l.), Czech Republic, in a deep loamy Stagnosol soil underlain by weathered paragneiss. One-point field calibration was made each spring at the time of sensor installation over three (for Virribs) or two (for ThetaProbes) consecutive years by taking sensor readings and soil samples (at least one 100 cm3 core sample near to each sensor) in parallel. A supplementary check was then made in the laboratory by taking readings of individual sensors, inserted into pre-made loamy-sand mixtures with various moisture contents. During both the field calibration and the laboratory check, the readings were taken manually, using either the AMET hand-held meter or the EMS ModuLog datalogger. The results suggest that the average slope of the secondary Virrib calibration curve (defined as the plot of y = sensor readings in terms of moisture content vs. x = soil moisture content determined gravimetrically) is near to unity, but the offsets are quite large and vary from probe to probe. The axial zone of influence of the Virrib sensors is up to about 30 cm, as it follows from both laboratory and field observations. The results of the laboratory check of Virribs were biased, because the volume of the soil was not large enough and the soil had different dry bulk densities at different moisture contents. The field secondary calibration curve of ThetaProbes appears to be roughly linear, in contrast to the laboratory calibration curve, because of absence of very low moisture contents in the field. If the same calibration line is applied to several different depths, then its slope is statistically significantly lower then unity, due to the dependence of ThetaProbe readings on the soil bulk density. The overall accuracy of the sensors and its components due to different factors is estimated from the statistics of repeated measurements.

The present article describes changes in specific activities and fluctuations in the ratio of natural 40K and artificial 137Cs radionuclides in soil samples taken from different places of Lithuanian territory. The samples of soil have been selected from the districts polluted after the accident in Chernobyl nuclear plant performing nuclear testing operations. The study has established the main physical and chemical properties of soil samples and their impact on the concentration of 40K activities. 137Cs/40K specific activities in soil have been observed under the dry weight of the sample that varied from 0.0034 to 0.0240. The results of the study could be used for establishing and estimating 137Csand 40K transfer in the system “soil-plant”. Santrauka Straipsnyje nagrinėjama gamtinės (40K) ir dirbtinės (137Cs) kilmės radionuklidų savitųjų aktyvumų ir jų santykio kaita skirtinguose Lietuvos teritorijos dirvožemiuose. Dirvožemio mėginiai parinkti iš vietovių, kurios buvo labiau užterštos po Černobylio atominės elektrinės avarijos ir buvusių branduolinių bandymų. Tyrimo metu nustatytos pagrindinės fizinės cheminės dirvožemio savybės ir jų poveikis 40K aktyvumų koncentracijai. 137Csir 40K savitieji aktyvumai dirvožemyje tirti esant sausam mėginio svoriui. 137Cs savitieji aktyvumai sausame dirvožemyje svyravo nuo 1,1±1,0 iki 14,3±0,9 Bq/kg, o 40K savitieji aktyvumai – nuo 326±29 iki 740±15 Bq/kg. 137Csir 40K savitųjų aktyvumų santykis skirtingų vietovių dirvožemiuose kito nuo 0,0034 iki 0,0240 Bq/kg. Tyrimo rezultatai gali būti panaudoti, nustatant ir įvertinant 137Csir 40K pernašą sistemoje dirvožemis–augalai. Raktiniai žodžiai: 137Cs; 40K; savitasis aktyvumas; aktyvumų santykis; dirvožemis; priesmėlis; priemolis