Digitally interpreting traditional folk crafts

The cultural heritage preservation requires that objects persist throughout time to continue to communicate an intended meaning. The necessity of computer-based preservation and interpretation of traditional folk crafts is validated by the decreasing number of masters, fading technologies, and crafts losing economic ground. We present a long-term applied research project on the development of a mathematical basis, software tools, and technology for application of desktop or personal fabrication using compact, cheap, and environmentally friendly fabrication devices, including '3D printers', in traditional crafts. We illustrate the properties of this new modeling and fabrication system using several case studies involving the digital capture of traditional objects and craft patterns, which we also reuse in modern designs. The test application areas for the development are traditional crafts from different cultural backgrounds, namely Japanese lacquer ware and Norwegian carvings. Our project includes modeling existing artifacts, Web presentations of the models, automation of the models fabrication, and the experimental manufacturing of new designs and forms

An effective and efficient testing methodology for correctness testing for file recovery tools

We hereby develop an effective and efficient testing methodology for correctness testing for file recovery tools across different file systems. We assume that the tool tester is familiar with the formats of common file types and has the ability to use the tools correctly. Our methodology first derives a testing plan to minimize the number of runs required to identify the differences in tools with respect to correctness. We also present a case study on correctness testing for file carving tools, which allows us to confirm that the number of necessary testing runs is bounded and our results are statistically sound. <br /

Development of a micro-extruder with vibration mode for microencapsulation of human keratinocytes in calcium alginate

Microencapsulation is a promising technique to form microtissues. The existing cell microencapsulation technologies that involved extrusion and vibration are designed with complex systems and required the use of high energy. A micro-extruder with an inclusion of simple vibrator that has the commercial value for creating a 3D cell model has been developed in this work. This system encapsulates human keratinocytes (HaCaT) in calcium alginate and the size of the microcapsules is controllable in the range of 500-800 µm by varying the flow rates of the extruded solution and frequency of the vibrator motor ( I 0-63 Hz). At 0.13 ml/min of flow rate and vibration rate of 26.4 Hz, approximately 40 ± IO pieces of the alginate microcapsules in a size 632.14 ± I 0.35 µm were produced. Approximately I 00 µm suspension of cells at different cells densities of 1.55 x I 05 cells/ml and 1.37 x I 07 cells/ml were encapsulated for investigation of microtissues formation. Fourier transform infrared spectroscopy (FTIR) analysis showed the different functional groups and chemistry contents of the calcium alginate with and without the inclusion of HaCaT cells in comparison to the monolayers of HaCaT cells. From Field Emission Scanning Electron Microscope (FESEM) imaging, calcium alginate microcapsules were characterised by spherical shape and homogenous surface morphology. Via the nuclei staining, the distance between cells was found reduced as the incubation period increased. This indicated that the cells merged into microtissues with good cell-cell adhesions. After 15 days of culture, the cells were still viable as indicated by the fluorescence green expression of calcein­acetoxymethyl. Replating experiment indicated that the cells from the microtissues were able to migrate and has the tendency to form monolayer of cells on the culture flask. The system was successfully developed and applied to encapsulate cells to produce 3D microtissues

Development of a micro-extruder with vibration mode for microencapsulation of human keratinocytes in calcium alginate

Microencapsulation is a promising technique to form microtissues. The existing cell microencapsulation technologies that involved extrusion and vibration are designed with complex systems and required the use of high energy. A micro-extruder with an inclusion of simple vibrator that has the commercial value for creating a 3D cell model has been developed in this work. This system encapsulates human keratinocytes (HaCaT) in calcium alginate and the size of the microcapsules is controllable in the range of 500-800 µm by varying the flow rates of the extruded solution and frequency of the vibrator motor ( I 0-63 Hz). At 0.13 ml/min of flow rate and vibration rate of 26.4 Hz, approximately 40 ± IO pieces of the alginate microcapsules in a size 632.14 ± I 0.35 µm were produced. Approximately I 00 µm suspension of cells at different cells densities of 1.55 x I 05 cells/ml and 1.37 x I 07 cells/ml were encapsulated for investigation of microtissues formation. Fourier transform infrared spectroscopy (FTIR) analysis showed the different functional groups and chemistry contents of the calcium alginate with and without the inclusion of HaCaT cells in comparison to the monolayers of HaCaT cells. From Field Emission Scanning Electron Microscope (FESEM) imaging, calcium alginate microcapsules were characterised by spherical shape and homogenous surface morphology. Via the nuclei staining, the distance between cells was found reduced as the incubation period increased. This indicated that the cells merged into microtissues with good cell-cell adhesions. After 15 days of culture, the cells were still viable as indicated by the fluorescence green expression of calcein­acetoxymethyl. Replating experiment indicated that the cells from the microtissues were able to migrate and has the tendency to form monolayer of cells on the culture flask. The system was successfully developed and applied to encapsulate cells to produce 3D microtissues

Error Level Analysis Technique for Identifying JPEG Block Unique Signature for Digital Forensic Analysis

The popularity of unique image compression features of image files opens an interesting research analysis process, given that several digital forensics cases are related to diverse file types. Of interest has been fragmented file carving and recovery which forms a major aspect of digital forensics research on JPEG files. Whilst there exist several challenges, this paper focuses on the challenge of determining the co-existence of JPEG fragments within various file fragment types. Existing works have exhibited a high false-positive rate, therefore rendering the need for manual validation. This study develops a technique that can identify the unique signature of JPEG 8 × 8 blocks using the Error Level Analysis technique, implemented in MATLAB. The experimental result that was conducted with 21 images of JFIF format with 1008 blocks shows the efficacy of the proposed technique. Specifically, the initial results from the experiment show that JPEG 8 × 8 blocks have unique characteristics which can be leveraged for digital forensics. An investigator could, therefore, search for the unique characteristics to identify a JPEG fragment during a digital investigation process

Forensic Analysis of WhatsApp Messenger on Android Smartphones

We present the forensic analysis of the artifacts left on Android devices by \textit{WhatsApp Messenger}, the client of the WhatsApp instant messaging system. We provide a complete description of all the artifacts generated by WhatsApp Messenger, we discuss the decoding and the interpretation of each one of them, and we show how they can be correlated together to infer various types of information that cannot be obtained by considering each one of them in isolation. By using the results discussed in this paper, an analyst will be able to reconstruct the list of contacts and the chronology of the messages that have been exchanged by users. Furthermore, thanks to the correlation of multiple artifacts, (s)he will be able to infer information like when a specific contact has been added, to recover deleted contacts and their time of deletion, to determine which messages have been deleted, when these messages have been exchanged, and the users that exchanged them.Comment: (c)2014. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0

Usefulness of Augmented Reality as a Tool to Support Online Learning

The global crisis following the outbreak of the Covid-19 epidemic has had an impact on the teaching and learning process (PdP). The main problem with PdP during the Covid-19 epidemic was the limitation in conducting face-to-face activities in the classroom. Therefore, a learning aid is needed to enable PdP to run optimally even though there is no face-to-face interaction between teachers and students. The research contribution is to highlight the application of Augmented Reality to support distance learning in the Covid-19 epidemic situation, specializing in Wood Carving Art for the subject of Visual Arts Education Form 4. The AR Wood Carving Art mobile application uses the ADDIE design model based on five phases, namely Analysis, Design, Development, Implementation, and Testing. The AR Wood Carving Art mobile application is evaluated based on its usefulness. The AR Wood Carving Art mobile application was evaluated among 27 students from 4 of SMK Pasir Gudang (Johor, Malaysia) and registered to Visual Arts. Based on the result, 80% of respondents strongly agree that the AR Wood Craving Art mobile application help respondents be more effective. It helps users to be more productive and giving ideas to users to be creative and innovative. One hundred percent of respondents strongly agree that the AR Wood Craving Art mobile application makes things that users want to achieve easier to do, and the AR Wood Craving Art mobile application does what users want. Eighty percent of respondents strongly agree that the AR Wood Craving Art application is useful and the application saves time when users use it. Therefore, the AR Wood Craving Art application is effectively used in learning which makes users more productive, creative, and innovative. In addition, the AR Wood Craving Art mobile application makes it easy for users to understand wood carving topics in visual arts subjects, and users can carry out educational and teaching activities like in a classroom

Kemudahan Penggunaan Augmented Reality sebagai Alat Bantu Pembelajaran Online bagi Meningkatkan Kinerja dan Prestasi Siswa Dalam Seni Ukiran Kayu

Krisis global pasca merebaknya epidemi Covid-19 berdampak pada proses belajar mengajar (PdP). Masalah utama pdP selama epidemi Covid-19 adalah keterbatasan dalam melakukan kegiatan tatap muka di dalam kelas. Oleh karena itu, diperlukan bantuan pembelajaran agar PdP dapat berjalan optimal meskipun tidak ada interaksi tatap muka antara guru dan siswa. Penelitian ini menyoroti penerapan Augmented Reality untuk mendukung pembelajaran jarak jauh dalam situasi epidemi Covid-19, khususnya dalam topik seni ukiran kayu. Aplikasi selular AR Wood Carving Art menggunakan model desain ADDIE. Aplikasi seluler AR Wood Carving Art dievaluasi berdasarkan kegunaannya (ease of use). Berdasarkan hasil penelitian, responden menyetujui bahwa aplikasi selular AR Wood Craving Art berguna dan aplikasi menghemat waktu ketika pengguna menggunakannya sehingga aplikasi selular AR Wood Craving Art efektif digunakan dalam pembelajaran yang membuat pengguna lebih produktif, kreatif, dan inovatif