Ground Segmentation Algorithm of Lidar Point Cloud Based on Ray-Ransac

Aiming at the problems of poor segmentation effect, low efficiency and poor robustness of the Ransac ground segmentation algorithm, this paper proposes a radar segmentation algorithm based on Ray-Ransac. This algorithm combines the structural characteristics of three-dimensional lidar and uses ray segmentation to generate the original seed point set. The random sampling of Ransac algorithm is limited to the original seed point set, which reduces the probability that Ransac algorithm extracts outliers and reduces the calculation. The Ransac algorithm is used to modify the ground model parameters so that the algorithm can adapt to the undulating roads. The standard deviation of the distance from the point to the plane model is used as the distance threshold, and the allowable error range of the actual point cloud data is considered to effectively eliminate the abnormal points and error points. The algorithm was tested on the simulation platform and the test vehicle. The experimental results show that the lidar point cloud ground segmentation algorithm proposed in this paper takes an average of 5.784 milliseconds per frame, which has fast speed and good precision. It can adapt to uneven road surface and has high robustness.

The density of planting mini-tubers on the yield of the first field generation of original seed potatoes

Цель исследований – изучение влияния густоты посадки мини-клубней на урожайность первого полевого поколения различных сортов картофеля. Исследования проведены в 2018–2019 годах в питомнике первого полевого поколения в условиях защищенного грунта ФГБОУ ВО «Алтайский государственный университет» (АлтГУ). Объект исследований – сорта картофеля Любава, Кемеровчанин, Тулеевский. Мини-клубни этих сортов были выращены на гидропонной установке лаборатории биотехнологии растений АлтГУ для дальнейшей посадки в теплицы. В 2018 году мини-клубни высаживались в контейнеры объемом 50 л, плотность посадки – 6,8 шт/м2. В 2019 году мини-клубни были высажены в гряды теплицы, плотность посадки – 5,0 шт/м2. Грунт теплицы состоял из смеси торфов, агроперлита, основных элементов питания (N, P, K). При контейнерном способе посадки (6,8 шт. мини-клубней на 1 м2) изучаемые сорта сформировали практически одинаковое количество клубней на куст: Любава – 7,85 шт., Кемеровчанин – 6,83 шт., Тулеевский – 7,05 шт. Сорт Любава (9,35 шт/куст) характеризовался максимальным числом клубней с одного растения при выращивании на грядах (густота посадки 5,0 шт/м2). Максимальный показатель средней массы клубней с 1 растения при густоте посадки 6,8 шт/м2 был у сорта Любава (687,74 г), минимальный – у сорта Тулеевский (593,86 г); показатель продуктивности растений сорта Кемеровчанин был равен 642,48 г. При выращивании мини-клубней на грядах наибольшая средняя масса клубней с одного растения получена у сортов Кемеровчанин (1178,13 г) и Любава (1008,25 г). Наибольшая урожайность первого полевого поколения при густоте посадки 6,8 шт/м2получена у сорта Любава (4,68 кг/м2), при густоте посадки 5,0 шт/м2 – у сорта Кемеровчанин (5,98 кг/м2). Количество семенной фракции исследуемых сортов на 1 м2в 2018 году составило 82,75–87,00%, в 2019 году – 41,75–53,25%. The aim of the research is to study the influence of the planting density of mini-tubers on the yield of the first field generation of various potato varieties. The research was carried out in 2018–2019 in the nursery of the first field generation in the conditions of protected soil of the FSBEI HO Altai State Agrarian University (ASAU). The objects of research were potato varieties Lyubava, Kemerovochanin, Tuleevsky. Mini-tubers of these varieties were grown on a hydroponic installation of the plant biotechnology laboratory of the ASAU for further planting in greenhouses. In 2018, mini-tubers were planted in containers with a volume of 50 liters, stocking density 6,8 pieces per 1 m2. In 2019, mini-tubers were planted in greenhouse ridges, planting density 5,0 pieces per 1 m2. The greenhouse soil consisted of a mixture of peat, agroperlite and basic nutrients (N, P, K). With the container planting method (6,8 pieces of mini-tubers per 1 m2), the studied varieties formed almost the same number of tubers per bush: Lyubava – 7,85 pieces, Kemerovochanin – 6,83 pieces, Tuleyevsky – 7,05 pieces. Variety Lyubava (9,35 pieces/bush) was characterized by the maximum number of tubers from 1 plant when grown on ridges (planting density 5,0 pieces per 1 m2). The maximum indicator of the average mass of tubers from 1 plant at a planting density of 6,8 pieces per 1 m2 was formed in the variety Lyubava (687,74 g), the minimum in the variety Tuleevsky (593,86 g); the productivity index of plants of the Kemerovochanin variety was 642,48 g. When growing mini-tubers on the ridges, the largest average mass of tubers per plant was obtained in the varieties Kemerovochanin (1178,13 g), Lyubava (1008,25 g). The highest yield of the first field generation with a planting density of 6,8 pieces/m2 was obtained for the variety Lyubava (4,68 kg/m2), with a planting density of 5,0 pieces/m2 – for the variety Kemerovchanin (5,98 kg/m2). The amount of seed fraction of the studied varieties per 1 m2in 2018 was 82,75–87,00%, in 2019–41,75–53,25%.

Influence of Growing Medium on the Parameters and Yield Capacity of the Mini Tuber Potato of the Charoite Variety

The creation of original seed grains of the Charoite variety, healed of pathogenic infections of various etiologies, was carried out through reproduction of the certified meristematic material of the microplants class. Mini tubers microplants were grown in 5.5 liter vessels on a “Agrobalt S” soil (control) mixed with peat and supplemented with 10% and 20% (of the volume) of the “ORVI” substrate. The use of the substrate “ORVI” mixed with peat and “Agrobalt S” soil positively influenced the growth, development and formation of tubers. The appliance of 10% of the “ORVI” substrate significantly increased the quantitative yield of mini tubers by 17% and the weight of tubers by 12.3%. The increase in the total number of mini tubers was due to the increase in tuber fraction from 10 to 30 mm. The appliance of a 20% “ORVI” substrate also led to an increase in the total number and mass of mini tubers. According to the EIA results, the mini tubers grown from microplants did not contain any latent viral infection. Tests on the seeds did not reveal symptoms of fungal diseases. Keywords: breed, potatoes, mini tubers, mass of tubers, peat fertilizer, substrate

Design Requirements Substantiation for an Automated Planting Unit for Potato Minitubers

The authors showed that the transition to the technology of virus-free minitubers mass production changed the machines requirements for planting original seed potatoes.(Research purpose) To develop a technological scheme and substantiate the design parameters of the planting apparatus of an automatic planter of potato minitubers.(Materials and methods) The development was based on an elevator-type planting apparatus. The authors decided to create a spoon design with the ability to grip and move into the guide casing one minituber in each spoon, eliminating the minitubers jumping from one spoon to another or pinching them when moving along the guiding casing to the furrow bottom. The diameters of the lower guide and upper drive rollers were theoretically substantiated in order to exclude the influence of the planting tubers sizes difference on the uniformity of their submitting into the furrow.(Results and discussion) The authors determined the minimum permissible elevator belt speed, which depended on the distance between the spoons on the elevator belt and the planting unit speed. The size of the upper driving reel diameter was justified from the condition that the spoon unfolded 180 degrees in at least 1.5 seconds, which ensured a tuber smooth transition to the back side of the spoon.(Conclusions) The authors developed a technological scheme of an automatic planting elevator type device for planting potato minitubers with a working speed of 6-9 kilometers per hour. It was found that the upper driving reel diameter was not less than 44 centimeters, and the lower guide roller diameter was not more than 12 centimeters. They showed that the double-sided design of scooping spoons with the possibility of installing replaceable bowls in them would ensure a high-quality planting of not only minitubers, but also subsequent reproductions of seed and ware potatoes with a tuber mass of 5-80 grams.

Signal coloration of young leaves of zucchini in the selection of plants with bi-colored fruit

Relevance. In accordance with the needs of the market, in 2008, a variety of zucchini Russian spaghetti with two-colored fruits was created. We faced difficulties in maintaining a high percentage of two-color forms in the variety population. To solve this problem, we studied the possibility of using markers of young zucchini leaves in the selection of forms with different fruit colors in technical ripeness.Material and conditions. The experience was started in 2005 to 2018 in the open ground on the basis of FSBSI FSVC. In the breeding nursery, research was conducted annually on 30 plants. The color of the fruit was taken into account only in the phase of technical ripeness. The best plants were propagated by incest. In the nursery breeding varieties of Russian spaghetti were sown by family. During 4 years in each family, at different stages of development, 50-100 plants were studied according to the color of the fruit and other economically useful characteristics.Results. For eleven years, incuchination and selection were carried out on two-color forms of zucchini Russian spaghetti to achieve homozygosity and, accordingly, to align the material with the color of the fruit. Some regularities of the influence of the number of integrirovanii on the color of the fruit has not been observed. Continuing to observe the plants, it was possible to establish a relationship between the color of the fruit in technical ripeness and the pattern on the lower (first) leaves. On plants with a marble pattern, the leaves were mostly green (reticulated); with yellow spots on the leaves – two-colored and with completely yellow leaves – yellow fruits. By selecting plants with yellow spots on the leaves in the early stages, in the phase of the 3-4-th real leaves, we were able to increase the percentage of plants with two-colored fruits in the population of the variety to 95.5-100%. All this greatly simplified the original seed production of zucchini Russian spaghetti.

Monitoring of original seed potatoes by method of field trial of samples

В статье рассмотрены результаты сравнительных испытаний сортообразцов оригинального семенного картофеля методом грунтового контроля. Испытательный участок грунтового контроля расположен на экспериментальной базе «Коренево» ФГБНУ «Федеральный исследовательский центр картофеля имени А.Г. Лорха» (Московская область) на дерново-подзолистой супесчаной почве. Предшественник – занятый пар (сидеральные культуры). Минеральные удобрения (азофоска с добавлением калимагнезии) вносили в дозах N90H90K135при нарезке гребней. Испытания сортообразцов проводили поделяночно на двух параллельных рядках по 50 клубней в каждом при схеме посадки 75×30 см, площадь делянки – 25 м2. В сезонах 2019–2020 годов было оценено 247 сортообразцов оригинального семенного картофеля с целью детальной проверки на соответствие нормативным допускам стандартных требований, касающихся их сортовой идентичности, наличия или отсутствия сортовых примесей и растений, пораженных вирусными и бактериальными болезнями, передающимися через семенной материал. По совокупности сортоотличительных признаков растения, стебля, листа и соцветия выявлено наличие растений с отклонениями типичности сортовых признаков в семи сортообразцах, включая мини-клубни (1 образец), первое полевое поколение из мини-клубней (5 образцов) и супер-суперэлиту (1 образец). На основе более детального изучения, в трех образцах первого полевого поколения из мини-клубней растения с отклоняющимися признаками были идентифицированы как примесь другого сорта. Превышение установленных допусков стандарта по вирусным болезням (YВК) выявлено у 80 сортообразцов, в том числе 17 образцах мини-клубней, 31 образце первого полевого поколения из мини-клубней и 38 образцах супер-суперэлиты. Растения с внешними признаками поражения бактериозами (контролируемыми допусками стандарта (черная ножка) не обнаружено. Показатели продуктивности растений и структуры урожая различались в зависимости от условий сезона, сроков созревания сортов и в основном соответствовали их сортовым характеристикам. Показатели продуктивности растений (масса клубней, г/куст) в зависимости от сорта, поколения и сезонных условий варьировали в диапазоне от 372 до 1055 г/куст. Наиболее высокие и стабильные по годам показатели по массе клубней отмечены у сортов Краса Мещеры, Гулливер, Садон, Фаворит, Метеор. The article considers the results of comparative tests of variety samples of original seed potatoes by the method of soil control. The soil control test on the experimental base Korenevo of the «Federal Research Center of Potatoes» (Moscow region) site is located on sod-podzolic sandy loam soil. The predecessor is a busy couple (green manure cultures). Mineral fertilizers (azofoska with the addition of potassium magnesium) were applied in doses of N90H90K135when cutting ridges. Testing of cultivars was carried out in plots on two parallel rows of 50 tubers each with a planting pattern of 75×30 cm, plot area – 25 m2. In 2019–2020 crop season comparative trials of seed potato samples where required out for detailed check of compliance with the normative tolerances of the standard requirements related to varietal identity and purity and, the level of viral and bacterial diseases transmitted through seed material 247 samples of original seed potatoes were evaluated to determine their varietal identity, the presence or absence of other varieties and plants affected by viral and bacterial diseases transmitted through seed material. By the totality of the varietal distinctive features of the plant, stem, leaf, inflorescence, the presence of plants with deviations in the typicality of varietal traits was revealed in 7 varieties, including mini-tubers (1 sample), the first field generation from mini-tubers (5 samples) and super-superquality (1 sample). On the basis of a more detailed study, in 3 samples of the first field generation from minitubers, plants with deviating traits were identified as an admixture of another variety. Exceeding the established tolerances of the standard for viral diseases (YВК) was detected in 80 samples, including 17 samples of mini-tubers, 31 samples of the first field generation from mini-tubers, and 38 samples of the super-superquality. Plants with external signs of bacteriosis infection (blackleg) controlled standard tolerances were not found. The indicators of plant productivity and the structure of the yield differed depending on the conditions of the season, the timing of ripening of varieties and basically corresponded to their varietal characteristics. Plant productivity indicators (tuber weight, g/bush), depending on the variety, generation and seasonal conditions, varied in the range from 372 to 1055 g/bush. The highest and most stable tuber weight indicators were observed in the varieties Krasa Meshchery, Gulliver, Sadon, Favorit, Meteor.

A comparative assessment: methods of growth of potato minitubers in summer greenhouses and in field under a covering material in the climate conditions of the Middle Volga region

The article presents the results of the comparison of two methods for potato minitubers cultivation, namely: in summer-type greenhouses and in field under a covering material in the climate conditions of the Middle Volga, Russia. This assessment was undertaken in the breeding and seed center of Agrostar LLC. The objective of the work is to assess the economic efficiency of both technologies for potato minitubers cultivation and justify the possibility of using the best of them for implementation in the original seed production. The micro-plants for the study were obtained from the biotechnological laboratories of the Samara Scientific Research Institute of Agricultural Sciences and the seedgrowing farm Tsirulev E.P., Samara region. The results obtained indicate that the most effective method of growth potato minitubers is in field under a covering material. This work was carried out as part of a comprehensive scientific and technical project “Development of breeding and seed production of potatoes in the Samara region”. Russian and Western European cultivars were used in the study.

Application of Defect Conversion Layer by Solution Growth for Reduction of TSDs in 4H-SiC Bulk Crystals by PVT Growth

We have developed the bulk growth technique to reduce threading screw dislocations (TSDs) by combining solution growth and PVT growth methods. More than 80 % of TSDs in original seed crystals were successfully converted to Frank defects on basal planes by the solution growth on 4° off C-face with Si-5at.% Ti solvent. After PVT growth on the as-grown surface of the conversion layer, TSDs in the original seed were successfully reduced. The presence of micrometer-size macrosteps in the initial stage of PVT growth is important to continue to propagate the converted Frank defects on basal planes during PVT bulk growth.