3D Scanning Techniques Research Articles

Study on mechanical properties and failure mechanism of hard rock with stiff discontinuities based on 3D printing

To examine the influence of stiff discontinuities with different angles and roughness on the stability of deep hard rock engineering, RLSD is created through the integration of 3D scanning, digital modeling, and 3D printing. The specimen's composition truly reflects the mineral components of the original rock. The impact of angle and roughness on the strength, deformation, and failure characteristics of RLSD is explored by uniaxial tests. The failure process and mechanism of specimens under the influence of stiff discontinuity feature are investigated through the integration of DIC, AE, and SEM test. The study results demonstrate that achieving highly similar specimen of hard rock containing stiff discontinuities with different angles and roughness is attainable by utilizing rock-like materials based on original rock mineral components and employing a combination of 3D scanning and 3D printing techniques. The peak strength, peak strain and elastic modulus of RLSD increase with the increase of JRC, and there is a V-shaped trend of“decrease first and then increase” with the increase of angle. The failure mode of RLSD shows the change rule of tension failure - tension-shear composite failure - shear failure - tension-shear composite failure - tension failure with the increase of angle. At angles of 60° and 75°, a sudden increase in hit and energy of AE feature is observed in RLSD, resulting in brittle failure. The cumulative energy exhibits a positive correlation with JRC. Based on the test results, an empirical estimation formula is established for the uniaxial compressive strength of RLSD, considering the influence of angle and JRC. The research results can provide reference for estimating the strength of surrounding rock in deep underground engineering as well as disaster prevention and control.

Study on Mechanical Model for Postpeak Shear Behavior of Rock Joints Based on Degradation Characteristics of the 3D Morphology

The 3D morphology of the joint surface significantly influences the shear behavior of the jointrock. Constant normal load (CNL) direct shear tests with different shear displacement were conducted to understand the shear stress changing with joint roughness and damage degree during shear. The rough joint specimens were prepared using 3D scanning and printing techniques, and shear tests with different normal stresses and shear displacements were performed. Four different parameters and the damaged area quantitatively described by the image binarization and box dimension were calculated and compared to study the roughness evolution of joint surfaces. The experimental results demonstrated that the roughness parameter and shear stress decrease and approach constant values with increasing shear displacement. A JRC degradation model was presented based on regression analyses to evaluate the JRC values of rock joints under various displacements to replace it in the JRC–JCS model. Additionally, a new postshear behavior modeling was proposed for rock joints based on surface degradation characteristics under various initial joint roughness coefficients (JRC0) and normal stress. The stress–displacement curves resulting from the proposed modified model work well in predicting the postpeak stress–displacement curve, which can prove the effectiveness of the postpeak shear behavior modeling.

Experimental Investigation on the Influence of Strength Grade on the Surface Fractal Dimension of Concrete under Sulfuric Acid Attack

The corrosion of alkaline concrete materials exposed to a sulfuric acid environment is becoming more and more prevalent, and its damage assessment is becoming more and more imperative. This study aims to describe the corroded surfaces of concrete with different strength grades (C30, C50, C80) in sulfuric acid environments in terms of their three-dimensional fractal dimension. Three kinds of concrete with varying strength grades, namely C30, C50, and C80, were immersed in a sulfuric acid solution with pH ≈ 0.85 for four distinct corrosion durations, specifically 0, 28, 56, and 165 days, in accelerated corrosion tests. The 3D laser scanning technique was utilized to capture the 3D coordinates of the surface points of the concrete cylinder before and after corrosion. The fractal dimension of concrete’s uneven surface before and after corrosion was computed via the cube covering method, and the mass loss of the concrete specimen was also obtained. The outcomes demonstrate that the three-dimensional fractal dimension provides a new method for characterizing the degree of corrosion deterioration of concrete samples affected by sulfuric acid via laser scanning technology. From the perspective of the appearance, mass loss, and fractal dimension of a rough surface in the sulfuric acid environment at a pH level of approximately 0.85, the degree of the corrosion deterioration of concrete is ranked from high to low as C80 > C50 > C30. These fractal dimensions of the concrete’s corroded surfaces with various strength grades increase rapidly in the initial period. However, as the corrosion time progresses, the growth rate of the corroded surface fractal dimension gradually decelerates and tends towards stability, which accords with the law of exponential function. The widespread belief is that the higher the strength grade of concrete, the better its durability; however, this pattern varies in sulfuric acid corrosive environments. Therefore, based on this research, it is recommended that in extremely acidic environments (i.e., very low pH), more attention should be paid to high-strength grades of concrete.

Building Surface Defect Detection Using Machine Learning and 3D Scanning Techniques in the Construction Domain

The rapid growth of the real estate market has led to the appearance of more and more residential areas and large apartment buildings that need to be managed and maintained by a single real estate developer or company. This scientific article details the development of a novel method for inspecting buildings in a semi-automated manner, thereby reducing the time needed to assess the requirements for the maintenance of a building. This paper focuses on the development of an application which has the purpose of detecting imperfections in a range of building sections using a combination of machine learning techniques and 3D scanning methodologies. This research focuses on the design and development of a machine learning-based application that utilizes the Python programming language and the PyTorch library; it builds on the team′s previous study, in which they investigated the possibility of applying their expertise in creating construction-related applications for real-life situations. Using the Zed camera system, real-life pictures of various building components were used, along with stock images when needed, to train an artificial intelligence model that could identify surface damage or defects such as cracks and differentiate between naturally occurring elements such as shadows or stains. One of the goals is to develop an application that can identify defects in real time while using readily available tools in order to ensure a practical and affordable solution. The findings of this study have the potential to greatly enhance the availability of defect detection procedures in the construction sector, which will result in better building maintenance and structural integrity.

OPTIMIZATION OF VR APPLICATION IN TEXTURING CULTURAL HERITAGE

Abstract. The research question underlying this short essay refers to the possibility of realizing through a well-established workflow a high level of immersivity in the VR representation of Cultural Heritage to be used as a working tool by architects and renovators as well as heritage scholars. At present active or passive 3D scanning techniques are a known reality where the choice of data acquisition system depends both on the final purpose and characteristics of the object to be surveyed. With the maturity achieved in point cloud acquisition, post processing phases and the development of BIM-based systems, the model has given the possibility to become a repository of information related to the existing, to be used for maintenance or renovation processes. If the model can represent the existing with a certain level of detail, it can be assumed that a differentiated Level of Immersivity can be organized depending on the specific needs it intends to fulfil. In the context of renovation or preservation of Cultural Heritage, the potential offered by VR becomes more interesting when it can provide a realistic portrait not only of the geometry, but also of the materiality and state of preservation of the buildings. This research opens new possibilities to develop tools to aid designers and renovators in degradation analysis, intervention projects, and scheduled maintenance. The research question starts analyzing the possibility of creating photorealistic immersive environments that are easy to access, organized based on surveys of existing heritage buildings using specific datasets.

A LIVING LAB APPROACH FOR CONCURRENT 3D DOCUMENTATION OF AN ARCHITECTURAL RENOVATION PROJECT – A SHOWCASE OF GUNSAN CIVIC CULTURAL CENTER

Abstract. This paper explores the integration of 3D documentation within a living lab framework for the renovation of the Gunsan Civic Cultural Center. The study emphasizes the importance of architectural renovation in contemporary sustainability and social resilience, highlighting the unique challenges of adapting existing structures. Our approach combines advanced 3D scanning techniques, such as drone filming, photogrammetry, LiDAR scanning, and hybrid modeling, with the living lab methodology, enabling real-world experimentation and stakeholder engagement. Our showcase on the Gunsan Civic Cultural Center illustrates the practical application of these techniques in material reuse and cultural performance planning, emphasizing community participation and collaborative decision-making. The living lab approach, central to our methodology, fosters dynamic interaction among architects, builders, community members, and local authorities, enhancing communication and project outcomes. This study contributes to the field by showcasing how concurrent 3D documentation in a living lab setting can revitalize heritage sites, ensuring their sustainable future while actively involving the community. The lessons and discussions drawn from this project highlight the potential of this approach in broader architectural and urban development contexts.

3D Morphological Scanning and Environmental Correlates of Bufo gargarizans in the Yellow River Basin

Morphology plays a crucial role in understanding the intricacies of biological forms. Traditional morphometric methods, focusing on one- or two-dimensional geometric levels, often fall short of accurately capturing the three-dimensional (3D) structure of organisms. The advent of 3D scanning techniques has revolutionized the study of organismal morphology, enabling comprehensive and accurate measurements. This study employs a 3D structured light scanning system to analyze the morphological variations in the Chinese toad (Bufo gargarizans Cantor, 1842) along the Yellow River Basin. The 3D digital model obtained from the scan was used to calculate various morphological parameters including body surface area, volume, fractal dimensions, and limb size. The research explores geographic variability patterns and identifies environmental drivers affecting the 3D phenotypic variation of B. gargarizans. Results reveal a bimodal pattern of variation in the toad population, with higher elevations exhibiting smaller body sizes, greater appendage proportions, and more complex body structures. Linear regression analyses highlight the influence of elevation and annual mean temperature on the morphological variation of B. gargarizans, with elevation playing a significant role. This study underscores the significance of 3D morphometric analysis in unraveling the intricacies of organismal morphology and understanding the adaptive strategies of species in diverse environments.

The Importance of Virtual Reality in the Conservation of Cultural Heritage: An Examination of the Penataran Temple Case Study in Blitar Regency, East Java

Introduction: Visualization of digital archives and applications play a crucial role in preserving cultural heritage. Utilizing efficient 3D scanning, modeling, and deep learning-based reconstruction techniques enables the revelation of hidden parts of Penataran Temple Sample in Blitar Regency, East Java. This research emphasizes the utilization of virtual reality (VR) systems as digital repositories for Penataran Temple Example, facilitating in-depth exploration of this cultural asset. The importance of applications such as guided tours, computer-aided design, and geographic information systems increases in the examination of cultural heritage, offering a deeper and more comprehensive understanding of the preserved cultural wealth. Methods: The methodology used in this research includes photogrammetry, accurate photogrammetric assessment, and the utilization of deep learning. Information obtained from these three avenues is combined to construct a three-dimensional Point cloud, serving as the foundation for the digital repository of Penataran Temple Sample. Virtual reality (VR) platforms enable individuals to observe the temple through both first-person and aerial perspectives, featuring customizable interfaces within the virtual reality setting. Results: The research activities are dedicated to creating a digital repository for Penataran Temple Sample located in Blitar Regency, East Java using 3D Point cloud data. Data acquisition of Point cloud for comprehensive coverage of temple structures and hidden reliefs is achieved through the application of advanced photogrammetric measurements and deep learning technology. A virtual reality (VR) system is developed to offer deep visualization capabilities, including first-person perspectives and aerial views, fostering a profound understanding of the cultural significance and architectural design of the temple. To enhance the realism of the VR experience and enable mapping functions, a 3D simulation engine is incorporated. The utilization of the first-person perspective allows detailed virtual exploration and collision detection, while aerial views contribute to a comprehensive understanding of the temple architecture. Discussion: The digital archive system of Penataran Temple Sample leverages Virtual Reality (VR) technology to integrate 3D Point cloud data from various sources. This system facilitates both first-person perspectives and aerial perspectives, allowing comprehensive examination and in-depth understanding of the temple architectural layout. Accurate 3D data generation is achieved through the utilization of Unmanned Aerial Vehicles (UAVs), photogrammetry technology, and deep learning techniques. Conclusion: The investigation focuses on the utilization of VR technology as a digital repository at Penataran Temple Sample, employing 3D Point cloud methodology. Its primary aim is to provide engaging visual encounters and comprehensive understanding of the architectural complex. Furthermore, this research will encompass detailed 3D measurements and the creation of high-precision VR renderings of the complete temple structures. Additionally, there are opportunities to design VR applications for remote utilization and to produce stereoscopic perspectives through holographic means. The anticipation is that VR will play a significant role in the preservation and interpretation of the heritage of Penataran Temple Sampled in Blitar Regency, East Java, while also demonstrating potential for diverse applications across various platforms and settings.

Normal Reorientation for Scene Consistency.

With the remarkable progress of 3D scanning technique, the captured indoor scenes appear increasingly in last decade. Generating orientation-consistent normals for indoor point clouds is a fundamental and important task. The existing orientation rectification methods pay more attention to object-level targets with connected surface. However, it is challenging to compute consistent surface orientation for real scanned indoor point clouds. In this paper, we analyze the causes of this difficulty and propose a new normal reorienting framework for indoor scene consistency, namely NRSC. It first estimates normals for an indoor point cloud and extracts all the connected regions. We then design and construct an abstract orientation bridging tree (OBT) to organize the extracted regions in a hierarchical way. For all node regions, NRSC iteratively implements a set of orientation propagations to generate locally orientation-consistent regions. Moreover, we define an auxiliary viewpoint set for each pairwise parent-child node regions and introduce a voting mechanism to rectify the region orientation of child node according to its parent. After processing all the child node regions along OBT, we finally eliminate the orientation inconsistencies between related regions. Multi-groups of experimental results on both fused indoor scenes and single-view-scenes show that our method generates globally consistent orientation for indoor point clouds.

Three-Dimensional Imaging in Agriculture: Challenges and Advancements in the Phenotyping of Japanese Quinces in Latvia

This study presents an innovative approach to fruit measurement using 3D imaging, focusing on Japanese quince (Chaenomeles japonica) cultivated in Latvia. The research consisted of two phases: manual measurements of fruit parameters (length and width) using a calliper and 3D imaging using an algorithm based on k-nearest neighbors (k-NN), the ingeniously designed “Imaginary Square” method, and object projection analysis. Our results revealed discrepancies between manual measurements and 3D imaging data, highlighting challenges in the precision and accuracy of 3D imaging techniques. The study identified two primary constraints: variability in fruit positioning on the scanning platform and difficulties in distinguishing individual fruits in close proximity. These limitations underscore the need for improved algorithmic capabilities to handle diverse spatial orientations and proximities. Our findings emphasize the importance of refining 3D scanning techniques for better reliability and accuracy in agricultural applications. Enhancements in image processing, depth perception algorithms, and machine learning models are crucial for effective implementation in diverse agricultural scenarios. This research not only contributes to the scientific understanding of 3D imaging in horticulture but also underscores its potential and limitations in advancing sustainable and productive farming practices.

Comparison of Traditional Impression and 3D Ear Scanning Techniques, Earmold Comfort, and Audiology Clinical Implications: A Pilot Study.

This study investigated clinical aspects of the traditional ear impression and 3D ear scanning techniques. Adult earmold-users and non-users participated in this study. The earmold-users also participated in the earmold comfort comparison study by wearing earmolds from both techniques, one set a week according to a randomized sequence. Multiple clinical aspects of both techniques according to the participants and audiology professionals were recorded. Results revealed a preference for the 3D-scanning technique, which was perceived as more comfortable although both techniques were perceived as safe. Although the earmolds might have issues from both techniques, there was no significant difference in the perception of earmolds. Experience with the specific technique can affect the responses from the professionals. Compared to the traditional technique, 3D-scans had higher fixed but less variable costs and procedure times. A special clinical case was included and indicated that 3D-scans could be an option for specific patients. This study led to a better understanding of the two techniques clinically. With increasing involvement of new technology and more young professionals joining the profession of audiology, 3D ear scanning could be a viable consideration for audiology practices.

Establishing Allometric Equation based on 3D Scanning Technique - Non-destructive Sampling Method

Establishing Allometric Equation based on 3D Scanning Technique - Non-destructive Sampling Method

Leveraging Additive Manufacturing and Reverse Engineering for Circular Economy-Driven Remanufacturing of Hydraulic Drive System Components

In response to the imperative of sustainability and resource efficiency, this article introduces an innovative framework for the remanufacture of hydraulic drive system components, firmly rooted in the tenets of the circular economy. This method mixes cutting-edge additive manufacturing technologies, meticulous 3D scanning techniques, and the rigorous discipline of reverse engineering to rebuild active elements within hydraulic drive systems. Fundamental to this framework is a resolute commitment to the repurposing of non-defective components, fostering a closed-loop system that systematically curtails waste generation and significantly diminishes the environmental footprint associated with hydraulic drive system maintenance. This article presents a meticulous examination of the remanufacturing process for a flowmeter, elucidating the intricate integration of additive manufacturing technology and the precision of 3D scanning to restore a previously damaged rotor. Through this interdisciplinary approach, we aim to elucidate the manner in which contemporary engineering practices can be harnessed to catalyze circularity, enhance resource efficiency, and increase sustainability within industrial operations. By demonstrating the efficacy of additive manufacturing and reverse engineering in hydraulic system remanufacturing, this article contributes significantly to the discourse on sustainable engineering methodologies, underlining their pivotal role in shaping a more environmentally conscientious, circular economy.

Geospatial Tools for Determining Visitor Carrying Capacity in Tourist Streets and Public Spaces of Historic Centres

This paper presents a methodology for using geospatial tools to enact efficient tourism planning and management in streets and other public spaces in historic centres. The study uses 3D laser scanning, GIS, and spatial data processing techniques to analyse the visitor carrying capacity of streets near cultural attractions. The methodology was tested on Miguelete Street in València (Spain), next to the Cathedral. The results show that these digital tools are efficient and accurate for the spatial analysis of visitor carrying capacity studies.

Analysis of mesoscopic mechanical dynamic characteristics of ballast bed with under sleeper pads

The meso-dynamical behaviour of a high-speed rail ballast bed with under sleeper pads (USPs) was studied. The geometrically irregular refined discrete element model of the ballast particles was constructed using 3D scanning techniques, and the 3D dynamic model of the rail–sleeper–ballast bed was constructed using the coupled discrete element method–multi-flexible-body dynamics (DEM–MFBD) approach. We analyse the meso-mechanical dynamics of the ballast bed with USPs under dynamic load on a train and verify the correctness of the model in laboratory tests. It is shown that the deformation of the USPs increases the contact area between the sleeper and the ballast particles, and subsequently the number of contacts between them. As the depth of the granular ballast bed increases, the contact area becomes larger, and the contact force between the ballast particles gradually decreases. Under the action of the elastic USPs, the contact forces between ballast particles are reduced and the overall vibration level of the ballast bed can be reduced. The settlement of the granular ballast bed occurs mainly at the shallow position of the sleeper bottom, and the installation of the elastic USPs can be effective in reducing the stress on the ballast particles and the settlement of the ballast bed.

Trajectory reconstruction of a wingtip segment separated from an aircraft using CFD simulation

Reconstructing the trajectory of the disintegrated component in an aircraft using numerical methods is anticipated to be a valuable technology for air crash investigation. The motion of separated objects in the air is significantly influenced by aerodynamic loads, making it necessary to employ computational fluid dynamics to estimate the forces and moments acting on the objects. To address the limitations of current methods, a multi-zone dynamic mesh method was utilized and validated via a store separation case, demonstrating good consistency with wind tunnel data. Since the trajectory of the wingtip is highly dependent on the center of gravity and mass properties, a predictive-level finite element model was developed using 3D scanning and reverse engineering techniques. Trajectories of the wingtip for a Tu-154M under various initial conditions were reconstructed, revealing nonlinear variations over time. By comparing the predicted crash position with the actual one, it is possible to ascertain the aircraft's condition at the moment when the wingtip separated.

Testing, analysis and design of wire and arc additively manufactured steel bolted connections

Capitalizing on Wire and Arc Additive Manufacturing (WAAM), 3D printed steel has shown significant potential in manufacturing large-scale steel structural elements in the construction industry. Due to the intrinsic difference in material properties, the mechanical performance of WAAM steel connections requires further investigation. In this paper, a total number of 24 WAAM steel coupon specimens with three different print layer orientations and 36 WAAM single-shear bolted connection specimens with one bolt of different design configurations were fabricated, dimensionally measured with 3D scanning technique, and tested under monotonic tension. The failure modes and ultimate capacities of the bolted connections were analysed, focusing on the print layer orientations of the WAAM steel plates. The current codified design provisions and design approaches proposed in the literature for steel structures were further evaluated by comparing the failure modes and ultimate capacities of the bolted connection specimens. This research shows that specimens with different print layer orientations present anisotropy phenomena in the coupon tests and bolted connection tests with differences of up to 10% and 20%, respectively. The relatively accurate predictions of the ultimate capacity of the WAAM steel bolted connection specimens following the current steel design standards are significantly compromised by predicting the incorrect failure modes, which could be attributed to the influence of anisotropic material properties of the WAAM steel plates and the failure modes of tilt-bearing and the end-splitting not being considered in current design provisions. This research conducted systematic experimental investigations focusing on the material properties of WAAM steel and the structural behaviours of WAAM single-shear bolted connections, which could potentially promote the application of WAAM technology in construction industry.

Experimental investigation on mode I fracture behavior of sandstone after grouting filling under three-point bending

The widespread presence of fissures in natural rock masses poses numerous challenges to the design and construction of rock engineering. As an effective reinforcement method, grouting filling is crucial for maintaining the safety and stability of underground engineering. In this study, a testing and monitoring system was established to perform three-point bending tests on sandstone specimens with a pre-notch after grouting filling utilizing high-definition cameras and the rock mechanics testing machine. Combined with the digital image correlation (DIC) method and 3D scanning technique, the influence of grouting filling type on the mechanical behavior and fracture characteristics of sandstones was investigated. Simultaneously, a novel approach for quantitatively determining crack initiation and propagation was proposed based on the maximum principal strain theory. The results indicated that the peak load of specimens all tends to rise with the increase of filling rate and filling material strength. The fracture toughness and nominal tensile strength initially ascend and then slightly decline when the filling rate goes up, whereas both grow continuously as the filling material strength improves. Increasing the filling rate and filling material strength can decrease the opening degree of the pre-notch and postpone the development of the fracture process zone (FPZ). The crack propagates steadily to a certain length before remarkably increasing as the load rises, while the FPZ length exhibits a growth trend from slow to rapid and subsequently to sluggish. Moreover, the grouting filling effect will also have a pronounced impact on the crack propagation path and fracture surface morphology.

Contribution of Lasergrammetry, Photogrammetry and Electrical Tomography for the Survey and 3D Representation of Caves: Case Study of the Cave of Kef El Baroud, Province of Benslimane, Morocco

The modeling of caves is constantly evolving and the classic modeling tools are giving way to new techniques that are more precise and more practical, indeed scientists are increasingly using 3D modeling to improve the representations of caves, in this study we have used lasergrammetry and photogrammetry which occupy an increasing place in the 3D representation of caves. Their simplicity favors their use for recording and modeling the parietal morphology of caves and the detailed representation of the complexity of Endokarst. As part of the geomorphological study of the Kef El Baroud Cave which is located in the province of Benslimane in Morocco, two modeling methods were carried out, it is a digital survey by lasergrammetry and by photogrammetry of the cave. and its parietal morphologies. The study was completed by a topographical survey with a DistoX rangefinder. The geophysical contribution by electrical tomography was also carried out. The 3D terrestrial laser scanning technique was performed by a LEICA RTC 345 scanner. These measurements made it possible to reconstruct the evolutionary stages of the paragenetic morphologies, and their relationships with the local geomorphology, and the structural elements. The field measurements were integrated into the morphometric analyzes of the digital models, which allowed a large number of observations.The surveys also made it possible to compare the results with those of the photogrammetry carried out by a reflex camera and a wide-angle lens with appropriate editing software.Lasergrammetry and its application have enabled us to precisely position within the point cloud all the details of the covered wall, and thus constitutes, alongside photogrammetry, an interesting means for the geomorphological study of the Caves. An electrical tomography study was coupled with the other measurements and made it possible not only to delimit the walls of the Cave according to the resistivity gradients but also to detect the very probable presence of fractured zones under the Cave which could constitute an aquifer.

Assessment Methods for Marginal and Internal Fit of Partial Crown Restorations: A Systematic Review.

Different methods are used for the analysis of marginal and internal fit of partial crowns, but not all of them are applicable for in vivo studies. The aim of this review is to search the available methods, described in the current literature, to assess marginal and internal fit in partial crowns. an electronic search was performed on Pubmed and Web of Science databases to find studies published from 1 January 2017 up to 2 March 2023, following PRISMA guidelines and Cochrane handbook for systematic reviews. The search strategy applied was: "(marginal) AND (fit OR gap OR adaptation OR discrepancy) AND (inlay OR onlay OR partial crown)". In vitro studies which evaluated marginal and internal fit on CAD CAM or 3D printed partial crowns were included in this review. Quality of the studies was assessed by using Quality Assessment Tool For In Vitro Studies (QUIN tool). 22 studies were included. Among conventional methods, direct view with microscope, indirect view on resin replicas, and silicone replica technique (SRT) were used. Considering new digital methods, micro-CT, SRT 3D and triple scan technique (TST) were applied. Among 2D methods, direct view technique is the most used marginal fit analysis. For a more comprehensive evaluation, a 3D digital analysis is suggested. SRT and indirect view are the only 2D methods available for in vivo analysis. A protocol for the application of TST for assessment in vivo is now available, but no studies are reported in literature yet.