scholarly journals Shape Reconstruction Processes for Interventional Application Devices: State of the Art, Progress, and Future Directions

2021 ◽  
Vol 8 ◽  
Author(s):  
Sujit Kumar Sahu ◽  
Canberk Sozer ◽  
Benoit Rosa ◽  
Izadyar Tamadon ◽  
Pierre Renaud ◽  
...  
Keyword(s):  
Electromagnetic Interference ◽  
Imaging Techniques ◽  
Poor Response ◽  
Shape Reconstruction ◽  
Alternative Methods ◽  
Small Scale ◽  
Reconstruction Process ◽  
Advantages And Disadvantages ◽  
Reconstruction Methods ◽  
Kinematic Models

Soft and continuum robots are transforming medical interventions thanks to their flexibility, miniaturization, and multidirectional movement abilities. Although flexibility enables reaching targets in unstructured and dynamic environments, it also creates challenges for control, especially due to interactions with the anatomy. Thus, in recent years lots of efforts have been devoted for the development of shape reconstruction methods, with the advancement of different kinematic models, sensors, and imaging techniques. These methods can increase the performance of the control action as well as provide the tip position of robotic manipulators relative to the anatomy. Each method, however, has its advantages and disadvantages and can be worthwhile in different situations. For example, electromagnetic (EM) and Fiber Bragg Grating (FBG) sensor-based shape reconstruction methods can be used in small-scale robots due to their advantages thanks to miniaturization, fast response, and high sensitivity. Yet, the problem of electromagnetic interference in the case of EM sensors, and poor response to high strains in the case of FBG sensors need to be considered. To help the reader make a suitable choice, this paper presents a review of recent progress on shape reconstruction methods, based on a systematic literature search, excluding pure kinematic models. Methods are classified into two categories. First, sensor-based techniques are presented that discuss the use of various sensors such as FBG, EM, and passive stretchable sensors for reconstructing the shape of the robots. Second, imaging-based methods are discussed that utilize images from different imaging systems such as fluoroscopy, endoscopy cameras, and ultrasound for the shape reconstruction process. The applicability, benefits, and limitations of each method are discussed. Finally, the paper draws some future promising directions for the enhancement of the shape reconstruction methods by discussing open questions and alternative methods.

scholarly journals 3D RECONSTRUCTION FROM MULTI-VIEW MEDICAL X-RAY IMAGES – REVIEW AND EVALUATION OF EXISTING METHODS

2015 ◽  
Vol XL-1-W5 ◽  
pp. 319-326 ◽  
Author(s):  
S. Hosseinian ◽  
H. Arefi
Keyword(s):  
3D Reconstruction ◽  
Imaging Techniques ◽  
Weight Bearing ◽  
Computer Assisted Surgery ◽  
3D Models ◽  
Alternative Methods ◽  
Computer Assisted ◽  
X Ray ◽  
Advantages And Disadvantages ◽  
Reconstruction Methods

The 3D concept is extremely important in clinical studies of human body. Accurate 3D models of bony structures are currently required in clinical routine for diagnosis, patient follow-up, surgical planning, computer assisted surgery and biomechanical applications. However, 3D conventional medical imaging techniques such as computed tomography (CT) scan and magnetic resonance imaging (MRI) have serious limitations such as using in non-weight-bearing positions, costs and high radiation dose(for CT). Therefore, 3D reconstruction methods from biplanar X-ray images have been taken into consideration as reliable alternative methods in order to achieve accurate 3D models with low dose radiation in weight-bearing positions. Different methods have been offered for 3D reconstruction from X-ray images using photogrammetry which should be assessed. In this paper, after demonstrating the principles of 3D reconstruction from X-ray images, different existing methods of 3D reconstruction of bony structures from radiographs are classified and evaluated with various metrics and their advantages and disadvantages are mentioned. Finally, a comparison has been done on the presented methods with respect to several metrics such as accuracy, reconstruction time and their applications. With regards to the research, each method has several advantages and disadvantages which should be considered for a specific application.

IMAGE BASED 3D FACE RECONSTRUCTION: A SURVEY

2009 ◽  
Vol 09 (02) ◽  
pp. 217-250 ◽  
Author(s):  
GEORGIOS STYLIANOU ◽  
ANDREAS LANITIS
Keyword(s):  
3D Reconstruction ◽  
Feature Detection ◽  
Low Cost ◽  
Reconstruction Algorithms ◽  
3D Face Reconstruction ◽  
Reconstruction Process ◽  
3D Face ◽  
Advantages And Disadvantages ◽  
Face Reconstruction ◽  
Reconstruction Methods

The use of 3D data in face image processing applications has received considerable attention during the last few years. A major issue for the implementation of 3D face processing systems is the accurate and real time acquisition of 3D faces using low cost equipment. In this paper we provide a survey of 3D reconstruction methods used for generating the 3D appearance of a face using either a single or multiple 2D images captured with ordinary equipment such as digital cameras and camcorders. In this context we discuss various issues pertaining to the general problem of 3D face reconstruction such as the existence of suitable 3D face databases, correspondence of 3D faces, feature detection, deformable 3D models and typical assumptions used during the reconstruction process. Different approaches to the problem of 3D reconstruction are presented and for each category the most important advantages and disadvantages are outlined. In particular we describe example-based methods, stereo methods, video-based methods and silhouette-based methods. The issue of performance evaluation of 3D face reconstruction algorithms, the state of the art and future trends are also discussed.

Design process for serious activities inspired by play and games: a problem solving with a board game from disengamement and gamification processes (Preprint)

2020 ◽  
Author(s):  
Stéphane Goria ◽  
Louise Dupet ◽  
Maëva Négroni ◽  
Gabriel Sega ◽  
Philippe Arnoux ◽  
...  
Keyword(s):  
Cancer Detection ◽  
Serious Games ◽  
Diagnostic Method ◽  
Scientific Literature ◽  
Imaging Techniques ◽  
Point Of View ◽  
Board Game ◽  
Advantages And Disadvantages ◽  
Design Result

BACKGROUND most serious games and other game-based tools are designed as digital games or escape games. They are designed for learning or sometimes in the field of medicine as an aid to care. However, they can also be seen as an aid to research, in our case, to evaluate the advantages and disadvantages of imaging techniques for cancer detection. OBJECTIVE we present a case study of action research on the design of a serious board game intended to consider the advantages and weaknesses of a diagnostic method in a different ways. The goal was to better understand the principles of designing a tool using game or play. METHODS we explicitly implemented another process than gamification to develop a structure reminiscent of the game to highlight the strengths and weaknesses of different imaging techniques from the point of view of the respondents (in this case specialists not directly involved in the project). Based on this feedback and the scientific literature on this subject, we detail the main categories of games and games developed for serious use in order to understand their differences. Concerning the cancer research part to which game contributes, our method is based on questions asked to experts and practitioners of this specialty. RESULTS an expert point of view translation tool in the form of a game has been realized to apprehend a research in a different way. CONCLUSIONS we show with the help of a diagram, some possible design paths leading to this type of design result including two hidden dimensions to consider (the awareness of the game or play by the "player" and his role as a contributor or recipient).

scholarly journals Computational Geometry-Based Surface Reconstruction for Volume Estimation: A Case Study on Magnitude-Frequency Relations for a LiDAR-Derived Rockfall Inventory

2021 ◽  
Vol 10 (3) ◽  
pp. 157
Author(s):  
Paul-Mark DiFrancesco ◽  
David A. Bonneau ◽  
D. Jean Hutchinson
Keyword(s):  
Computational Geometry ◽  
Surface Reconstruction ◽  
Power Law ◽  
Point Cloud ◽  
Point Clouds ◽  
Volume Estimation ◽  
Estimation Methods ◽  
Small Scale ◽  
Reconstruction Methods ◽  
3D Volume

Key to the quantification of rockfall hazard is an understanding of its magnitude-frequency behaviour. Remote sensing has allowed for the accurate observation of rockfall activity, with methods being developed for digitally assembling the monitored occurrences into a rockfall database. A prevalent challenge is the quantification of rockfall volume, whilst fully considering the 3D information stored in each of the extracted rockfall point clouds. Surface reconstruction is utilized to construct a 3D digital surface representation, allowing for an estimation of the volume of space that a point cloud occupies. Given various point cloud imperfections, it is difficult for methods to generate digital surface representations of rockfall with detailed geometry and correct topology. In this study, we tested four different computational geometry-based surface reconstruction methods on a database comprised of 3668 rockfalls. The database was derived from a 5-year LiDAR monitoring campaign of an active rock slope in interior British Columbia, Canada. Each method resulted in a different magnitude-frequency distribution of rockfall. The implications of 3D volume estimation were demonstrated utilizing surface mesh visualization, cumulative magnitude-frequency plots, power-law fitting, and projected annual frequencies of rockfall occurrence. The 3D volume estimation methods caused a notable shift in the magnitude-frequency relations, while the power-law scaling parameters remained relatively similar. We determined that the optimal 3D volume calculation approach is a hybrid methodology comprised of the Power Crust reconstruction and the Alpha Solid reconstruction. The Alpha Solid approach is to be used on small-scale point clouds, characterized with high curvatures relative to their sampling density, which challenge the Power Crust sampling assumptions.

scholarly journals In Vivo Imaging of Biodegradable Implants and Related Tissue Biomarkers

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2348
Author(s):  
Leon Riehakainen ◽  
Chiara Cavallini ◽  
Paolo Armanetti ◽  
Daniele Panetta ◽  
Davide Caramella ◽  
...  
Keyword(s):  
Imaging Modality ◽  
Imaging Techniques ◽  
Special Focus ◽  
Tissue Remodelling ◽  
Biodegradable Implant ◽  
Advantages And Disadvantages ◽  
Non Invasive ◽  
Positron Emission ◽  
Longitudinal Imaging

Non-invasive longitudinal imaging of osseointegration of bone implants is essential to ensure a comprehensive, physical and biochemical understanding of the processes related to a successful implant integration and its long-term clinical outcome. This study critically reviews the present imaging techniques that may play a role to assess the initial stability, bone quality and quantity, associated tissue remodelling dependent on implanted material, implantation site (surrounding tissues and placement depth), and biomarkers that may be targeted. An updated list of biodegradable implant materials that have been reported in the literature, from metal, polymer and ceramic categories, is provided with reference to the use of specific imaging modalities (computed tomography, positron emission tomography, ultrasound, photoacoustic and magnetic resonance imaging) suitable for longitudinal and non-invasive imaging in humans. The advantages and disadvantages of the single imaging modality are discussed with a special focus on preclinical imaging for biodegradable implant research. Indeed, the investigation of a new implant commonly requires histological examination, which is invasive and does not allow longitudinal studies, thus requiring a large number of animals for preclinical testing. For this reason, an update of the multimodal and multi-parametric imaging capabilities will be here presented with a specific focus on modern biomaterial research.

Approaches to motion control intellectualization of a mobile robot

2021 ◽  
Author(s):  
Stepan A. Lapshinov ◽  
Vadim A. Shakhnov ◽  
Anton V. Yudin
Keyword(s):  
Mobile Robot ◽  
Motion Control ◽  
Control Device ◽  
Alternative Methods ◽  
Design Solution ◽  
Movement Direction ◽  
Software Complex ◽  
Advantages And Disadvantages ◽  
Drive Control ◽  
Omni Wheel

The paper considers the principles of intelligent motion control of mobile robots using the example of omni-wheel modules. The proposed design solution uses components of movement intelligence in any direction, receiving commands from a human operator or above a standing automatic control device, consisting of an angle of movement direction and the required distance of movement. This paper presents an embodiment of using omni-wheels to move a mobile robot over a flat surface. Features of device and application of drive with three omni-wheels in comparison with differential drive are considered. Kinematics, basic principles of motion control formation, hardware and software complex for its implementation are described. There were revealed two alternative methods of organization of drive control in conditions of shortage of low-level hardware resources on the basis of 8-bit microcontroller, their advantages and disadvantages have been analyzed. Process support and materials have been presented that allows realizing the competitive advantages of development while minimizing the cost of components. Features of mobile robot travel route development have been mentioned on the example of competitive practice.

Accuracy of Failure Criteria Commonly Used for Ship Collision Simulations

2018 ◽  
Author(s):  
R. Villavicencio ◽  
Bin Liu ◽  
Kun Liu
Keyword(s):  
Finite Element ◽  
Failure Criteria ◽  
Small Scale ◽  
Finite Element Models ◽  
Impact Loads ◽  
Large Scatter ◽  
Element Analysis ◽  
Advantages And Disadvantages ◽  
Ship Collision ◽  
Double Hull

The paper summarises observations of the fracture response of small-scale double hull specimens subjected to quasi-static impact loads by means of simulations of the respective experiments. The collision scenarios are used to evaluate the discretisation of the finite element models, and the energy-responses given by various failure criteria commonly selected for collision assessments. Nine double hull specimens are considered in the analysis so that to discuss the advantages and disadvantages of the different failure criterion selected for the comparison. Since a large scatter is observed from the numerical results, a discussion on the reliability of finite element analysis is also provided based on the present study and other research works found in the literature.

scholarly journals Opportunities and Questions: A Short Report on Rubric Assessments in Asia and the Middle East

2019 ◽  
Author(s):  
Ronnie Goodwin
Keyword(s):  
Middle East ◽  
Assessment Tool ◽  
Relevant Literature ◽  
Alternative Methods ◽  
Learning Theories ◽  
Short Report ◽  
Rating Systems ◽  
Self Assessment ◽  
Advantages And Disadvantages ◽  
The Impact

This qualitative short report considers the viability of the use of rubrics or alternative methods to assess writing in Asia and the Middle East. The background of learning theories, assessment types, and self-assessment literature provides a foundation for further discussion of the appropriate use of rubrics, including the prioritization of criterion, the quality of scoring, the impact of organizational features on scoring, the influence of bias, and the best application of rubric assessment. Relevant points for further study are identified, such as differentiation in research between generalized analytical rating systems and rubric assessment with specific, empirical criterion. The contradictory research regarding the advantages and disadvantages of rubric assessment in comparison with holistic assessment are of particular and crucial interest for global pedagogy. Many of the reviewed Western articles excluded Asian perspectives- except for China- and thus present a limited understanding of social and educational compatibility with new assessments and rubric assessments in particular. The discussion identifies patterns and points of contention and seeks to explore viewpoints rather than limit the scope of inquiry and consideration thus noting that relevant literature suggests that with appropriate teacher training, teachers may appropriately use rubrics as a formative assessment tool for writing in Asia and the Middle East.

scholarly journals The Triumph of Large-Scale Agriculture and Its Socioeconomic Impact

2018 ◽  
Vol 43 (2) ◽  
pp. 95-106
Author(s):  
András Schlett ◽  
Judit Beke
Keyword(s):  
Rural Areas ◽  
Large Scale ◽  
Socioeconomic Impact ◽  
Small Scale ◽  
Production Methods ◽  
Advantages And Disadvantages ◽  
Key Drivers

Large-scale farming that utilizes industrial methods to intensify production is becoming more significant worldwide. This study explores this phenomenon and sheds light on its consequences. Contingency factors serve as key drivers when determining the advantages and disadvantages of both large-scale and small-scale farming. Significant shifts in agro-production methods have fundamentally altered ownership and production structures in agriculture and had a disastrous impact on the livelihoods of people living in rural areas.

scholarly journals THE EFFECT OF FERTILIZER SUBSIDY ON PADDY PRODUCTION OF SMALL SCALE FARMERS: SPECIAL REFERENCE IN POLONNARUWA DISTRICTIN SRI LANKA

2019 ◽  
Vol 1 (1) ◽  
pp. 33-44
Author(s):  
M B Ranathilaka ◽  
I.A.J Imbulana Arachchi
Keyword(s):  
Sri Lanka ◽  
Education Level ◽  
Living Condition ◽  
Alternative Methods ◽  
Small Scale ◽  
Sri Lankan ◽  
Paddy Farmers ◽  
Small Scale Farmers ◽  
Paddy Cultivation ◽  
Paddy Yield

Paddy cultivation is major part in rural agriculture sector in Sri Lanka. Majority of rural sector paddy farmers are small-scale producers. According to available data paddy production sector provides livelihood opportunities for large numbers of rural population, provide rice requirement of the nation, provide inputs to other industrial sector etc.To enhance small-scale farmers living condition as well as paddy production, Sri Lankan government promotes paddy farmers to use more fertilizer for their paddy cultivation activities. Therefore, Sri Lankan government provides subsidized fertilizer to enhance both paddy production and paddy yield per acre. Last few decades paddy production and paddy yield per acre data show continues increasing trend. At the same time government expenditure on fertilizer also becomes heavy burden to national budget. There are arguments for and against to fertilizer subsidy program and its practice. This study attempts to study the effect of fertilizer subsidy on paddy production and living condition of small-scale farmers in Polonnaruwa district in Sri Lanka. The data are used to estimate an econometric model to find the relationship between paddy productivity, fertilizer subsidy, agricultural infrastructure facilities and farmers education level. The data were collected from Bubula and Raja-elagama villages in Higurakgoda divisional secretariat in Polonnaruwa district. Structured questioner was used to collect the data from 150 farmers. The results show that there is significant relationship between paddy production and dependent variables named fertilizer subsidy, agricultural infrastructure facilities and farmers education level. Especially fertilizer subsidy and paddy productivity is significant at 5 per cent level and R2 was 0.68. This result shows that government main objective of fertilizer subsidy that improves paddy productivity has been fulfilled. At the same time, household income from paddy has also increased and it has affected their livelihoods. But poor agricultural infrastructural facilities have mitigated farmers’ income. Research results and some empirical evidence have concluded that it is important to find alternative methods to select suitable and needy farmers who are eligible to get fertilizer subsidy because conducting methods of distributing have made many kinds of effects on the efficiency of resource utilization, equity of income distribution as well as government budget. Agricultural infrastructure facilities are very important for making fertilizer subsidy programs more meaningful and to have a significant effect on enhancing paddy farmers’ living conditions.

Sign in / Sign up

Export Citation Format

Share Document