mechanical methods
Recently Published Documents


TOTAL DOCUMENTS

881
(FIVE YEARS 241)

H-INDEX

44
(FIVE YEARS 6)

Author(s):  
Brahim Jabir ◽  
Noureddine Falih

<span>In precision farming, identifying weeds is an essential first step in planning an integrated pest management program in cereals. By knowing the species present, we can learn about the types of herbicides to use to control them, especially in non-weeding crops where mechanical methods that are not effective (tillage, hand weeding, and hoeing and mowing). Therefore, using the deep learning based on convolutional neural network (CNN) will help to automatically identify weeds and then an intelligent system comes to achieve a localized spraying of the herbicides avoiding their large-scale use, preserving the environment. In this article we propose a smart system based on object detection models, implemented on a Raspberry, seek to identify the presence of relevant objects (weeds) in an area (wheat crop) in real time and classify those objects for decision support including spot spray with a chosen herbicide in accordance to the weed detected.</span>


Fire ◽  
2022 ◽  
Vol 5 (1) ◽  
pp. 7
Author(s):  
Leonel J. R. Nunes ◽  
Catarina I. R. Meireles ◽  
Carlos J. Pinto Gomes ◽  
Nuno M. C. Almeida Ribeiro

Invasive species are an environmental problem affecting worldwide ecosystems. In the case of Acacia dealbata Link., the negative impacts affect the productivity of the forests due to the competition established with native species while contributing to a significant increment in the available fuel load, increasing the risk of fire. In Portugal, chemical and mechanical methods are mostly used in the control of these species. However, the costs are often unsustainable in the medium term, being abandoned before completing the tasks, allowing the recovery of the invasive species. The establishment of value chains for the biomass resulting from these actions was pointed out by several authors as a solution for the sustainability of the control process, as it contributes to reducing costs. However, the problems in quantifying the biomass availability make it challenging to organize and optimize these actions. This work, which started from a dendrometrical analysis carried out in stands of A. dealbata, created a model to assess woody biomass availability. The model proved to be statistically significant for stands with trees younger than 20 years old. However, the amount of data collected and the configuration of the settlements analyzed do not allow extrapolation of the model presented to older settlements.


2022 ◽  
Vol 8 ◽  
pp. 205951312110478
Author(s):  
H Eray Copcu

Background Regenerative medicine is the fastest developing branch of plastic surgery in recent times. Adipose tissue is one of the largest and most important sources in the body for stromal cells. Although mechanical isolation methods are both very popular and have many advantages, they still have no accepted protocols. Objective We developed new protocols called indication-based protocols (IPs) for standardization and new techniques called mechanical stromal-cell transfer (MEST) by using ultra-sharp blades and dilution of adipose tissue with different solutions (saline, Ringer and 5% Dextrose) Methods & material: In order to obtain the desired physical structure (liquid, gel, solid) and the desired volume, four different types of IPs have been defined. Adipose tissue was prediluted with different solutions using 10 or 20 cc injectors in IPs 1 and 2, while condensed adipose tissue was used directly in IPs 3 and 4. Results In MEST, stromal cells were obtained from 100 mL of condensed fat using different IPs with 92% mean viability and cell counts of 26.80–91.90 × 106. Stromal cells can be obtained in the desired form and number of cells by using four different IPs. Conclusion Isolation of stromal cells by cutting fat with sharp blades will prevent the death of fat tissue and stromal cells and will allow high viability and cell count with our new technique. Predilution with different solutions: Diluting the condensed adipose tissue with the desired solutions (saline, Ringer or 5% Dextrose) before the adinizing process will provide even more stromal cells. Lay Summary Obtaining regenerative stromal cells from adipose tissue can be done by two methods: Enzymatic and mechanical. Mechanical methods have many advantages. Although mechanical stromal cell extraction from adipose tissue is very popular and many techniques have been described, there are still no accepted protocols, definition for the end product, and no consensus on the status of the stromal cells. In this study, stromal cells were obtained mechanically by using ultra-sharp blade systems, without exposing adipose tissue to blunt trauma. Thus, a higher number of cells and higher viability could be obtained. An “Indication based” protocol has been defined for the first time in order to obtain the desired number and status (solid, semi-solid, liquid) end product. Diluting the condensed adipose tissue with the desired solutions (saline, Ringer or 5% Dextrose) before the adinizing process will provide even more stromal cells. This will provide an opportunity for clinicians to obtain and apply a stromal cell solution for different indications in different anatomical regions.


Pharmaceutics ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 92
Author(s):  
Bryan J. Mathis ◽  
Misa Kusumoto ◽  
Alexander Zaboronok ◽  
Yuji Hiramatsu

Asthma is a life-altering, chronic disease of heterogenous origin that features a complex interplay of immune and environmental signaling. Although very little progress has been made in prevention, diverse types of medications and delivery systems, including nanoscale systems, have been or are currently being developed to control airway inflammation and prevent exacerbations and fibrosis. These medications are delivered through mechanical methods, with various inhalers (with benefits and drawbacks) existing, and new types offering some variety in delivery. Of particular interest is the progress being made in nanosized materials for efficient penetration into the epithelial mucus layer and delivery into the deepest parts of the lungs. Liposomes, nanoparticles, and extracellular vesicles, both natural and synthetic, have been explored in animal models of asthma and have produced promising results. This review will summarize and synthesize the latest developments in both macro-(inhaler) and micro-sized delivery systems for the purpose of treating asthma patients.


2021 ◽  
Vol 10 (24) ◽  
pp. 5944
Author(s):  
Alicja Jurecka ◽  
Maciej Papież ◽  
Paulina Skucińska ◽  
Artur Gądek

The term “soft tissue therapy” (STT) refers to mechanical methods of treatment involving passive kneading, pressing and stretching of pathologically tense tissues in supporting the process of recovery after surgery or trauma to the musculoskeletal system. The objective of this study was to review current scientific reports evaluating the effectiveness of the use of STT in patients with diseases or after surgical procedures of the knee joint. A systematic search of the popular scientific databases PubMed, Scopus and Embase was performed from inception to 15 October 2021. Eight articles met eligibility criteria and were included in the review. Six papers were related to disorders of the knee joint, while the remaining two studies were related to dysfunctions associated with the conditions after surgical intervention. The findings presented confirmed the effectiveness of STT in orthopaedic patients who showed an increase in lower limb functional parameters. The research has shown that the use of various methods of STT has a significant impact on increasing muscle activity and flexibility as well as increasing the range of motion in the knee joint. The physiotherapeutic methods used had a significant impact on reducing pain and increasing physical function and quality of life. The techniques used reduced the time to descend stairs in patients with knee osteoarthritis. This review summarises the effectiveness of STT as an important form of treatment for orthopaedic patients with various knee joint dysfunctions.


2021 ◽  
Vol 6 (2(62)) ◽  
pp. 47-52
Author(s):  
Igor Nevliudov ◽  
Dmytro Yanushkevych ◽  
Leonid Ivanov

The object of research is robotic military complexes used in the system of humanitarian demining. This work aims to study the requirements for robotic military complexes (including manipulators that are sucked into them) and to develop proposals for their use in humanitarian demining. The research is based on the application of a functional approach to the construction of models for the formation of requirements for robotic military complexes (RMC), which are sucked into the system of humanitarian demining. It is established that the creation of RMC requires a significant study of the core of the most important technologies that are needed to create the entire range of promising RMC. Thus the standard sample RMC can be presented in the form of set of functionally connected elements: the basic carrier, the mobile platform, the specialized hinged/built-in equipment in the form of a set of removable modules of useful (target) purpose, means of maintenance and service used at preparation for application and technical operation robot. The composition of specialized equipment is set based on the functional purpose of the RMC. The classification of RMC is given, which provides for their division into three categories: the first generation – controlled devices, the second generation – semi-autonomous devices and the third generation – autonomous devices. The analysis of modern RMC which are developed in Ukraine and the advanced countries of the world and the analysis of structure of components of system of humanitarian demining is carried out. It is established that the organization of the humanitarian demining system with the use of RMC should include of explosive objects (EO) reconnaissance, search, marking, their identification and direct demining. Unmasking signs of EO, as well as modern methods and detectors of EO detection are considered. One of the new promising methods of mine detection is parametric. However, in real application, the most promising is the use of a combination of electromagnetic, optical and mechanical methods. The application of the proposed approaches will increase the efficiency of humanitarian demining and reduce human losses in its implementation.


2021 ◽  
Vol 13 (12) ◽  
pp. 168781402110670
Author(s):  
Yanxiang Chen ◽  
Zuxing Zhao ◽  
Euiyoul Kim ◽  
Haiyang Liu ◽  
Juan Xu ◽  
...  

As wheels are important components of train operation, diagnosing and predicting wheel faults are essential to ensure the reliability of rail transit. Currently, the existing studies always separately deal with two main types of wheel faults, namely wheel radius difference and wheel flat, even though they are both reflected by wheel radius changes. Moreover, traditional diagnostic methods, such as mechanical methods or a combination of data analysis methods, have limited abilities to efficiently extract data features. Deep learning models have become useful tools to automatically learn features from raw vibration signals. However, research on improving the feature-learning capabilities of models under noise interference to yield higher wheel diagnostic accuracies has not yet been conducted. In this paper, a unified training framework with the same model architecture and loss function is established for two homologous wheel faults. After selecting deep residual networks (ResNets) as the backbone network to build the model, we add the squeeze and excitation (SE) module based on a multichannel attention mechanism to the backbone network to learn the global relationships among feature channels. Then the influence of noise interference features is reduced while the extraction of useful information features is enhanced, leading to the improved feature-learning ability of ResNet. To further obtain effective feature representation using the model, we introduce supervised contrastive loss (SCL) on the basis of ResNet + SE to enlarge the feature distances of different fault classes through a comparison between positive and negative examples under label supervision to obtain a better class differentiation and higher diagnostic accuracy. We also complete a regression task to predict the fault degrees of wheel radius difference and wheel flat without changing the network architecture. The extensive experimental results show that the proposed model has a high accuracy in diagnosing and predicting two types of wheel faults.


2021 ◽  
Vol 0 (12) ◽  
pp. 13-16
Author(s):  
E. A. Kosenko ◽  
◽  
D. K. Zakorsky ◽  
A. Du ◽  
N.K. Podchuvalova ◽  
...  

The chemical and mechanical methods of preparing metal surfaces before gluing have been examined. The strength test results for shear of adhesive bonds of aluminum and steel samples, the surfaces of which were prepared by grinding, shot-blasting with copper slag and chemical treatment in aqueous solutions of acids before gluing. The best results for shear strength of adhesive bonds are observed for samples whose surfaces were subjected to shot blasting with a copper slag, the worst ones are after chemical method of preparing in aqueous solutions of acids.


2021 ◽  
Vol 15 (4) ◽  
pp. 1619-1628
Author(s):  
Mberdoum Memti Nguinambaye ◽  
Ngam-Asra Nadjioroum ◽  
Otchom Boy Brahim

Cette étude s’inscrit dans le contexte de la valorisation des espèces végétales spontanées ayant des valeurs  nutritives et économiques afin de contribuer à leur domestication. Cette étude a consisté à tester les capacités germinatives des graines de l’Ampelocissus multistriata par les procédés physiques, chimiques et mécaniques d’une part et tester l’aptitude au bouturage des tiges feuillées, des tiges feuillées avec des racines tubéreuses d’autre part. Pour cela, une surface de 400 m2 a été délimitée au sein de la Faculté des Sciences Exactes et  Appliquées de l’Université de N’Djamena pour les deux tests. Par ailleurs, les procédés physiques, chimiques et mécaniques ont été menés à l’Université de Ouagadougou. Les résultats obtenus, ont montré que les tiges feuillées n’ont pas bouturé. Par contre, les tiges feuillées munies des racines tubéreuses ont bouturé à 73,23 %. En ce qui concerne la germination des graines, tous les procédés des traitements physiques, chimiques et mécaniques n’ont pas pu lever la dormance de ces graines. Leurs téguments, très durs, n’ont pas été scarifiés et cela n’a pas permis à l’eau et l’oxygène d’y entrer pour que les graines puissent germer. Seules, les graines ayant séjourné dans le tube digestif des animaux et qui ont été scarifiées par les enzymes intestinales et les sucs digestifs ont toutes germé. Il s’agit d’une endozoochorie. La connaissance des modalités de la propagation par les graines ou par les boutures peut apporter une importante contribution à la conservation de la diversité végétale, à la domestication et à la valorisation de cette plante.   English title: Germinative capacity of seeds and aptitude for cutting of stems, tuberous roots of the species Ampelocissus multistriata (Baker) Planch This study is part of the context of valuing spontaneous plant species with nutritional and economic values in order to contribute to their domestication. This study consisted in testing the germination capacities of the seeds of Ampelocissus multistriata by physical, chemical and mechanical methods on the one hand and testing the aptitude for cuttings of leafy stems, leafy stems with tuberous roots on the other hand. For this, an area of 400 m2 has been defined within the Faculty of Exact and Applied Sciences of the University of N’Djamena for the two tests. In addition, the physical, chemical and mechanical processes were carried out at the University of Ouagadougou. The results obtained showed that the leafy stems did not cuttings. In contrast, the leafy stems with tuberous roots cut at 73.23%. Regarding seed germination, not all physical, chemical and mechanical treatment processes were able to break the dormancy of these seeds. Their very hard seed coats were not scarified, and this did not allow water and oxygen to enter them for the seeds to germinate. Only the seeds which have stayed in the digestive tract of animals and which have been scarified by intestinal enzymes and digestive juices have all germinated. It is an endozoochory. Knowing the methods of propagation by seeds or cuttings can make an important contribution to the conservation of plant diversity, to the domestication and enhancement of this plant.


Sign in / Sign up

Export Citation Format

Share Document