Camera Technique Research Articles

Advanced additive manufacturing of self-healing composites: Exploiting shape memory alloys for autonomous restoration under mixed-mode loading

Applying Additive Manufacturing (AM) techniques has facilitated the production of innovative self-healing structures that can acclimate to environmental fluctuations by considering their damage response. This paper introduces a novel approach for fabricating AM composites reinforced with Shape Memory Alloys (SMAs) and possessing self-healing capabilities. The self-healing performance of the composites is assessed by subjecting undamaged and repaired samples to mixed mode I/II loading conditions using pre-cracked Semi-Circular Bending (SCB) specimens. Supplementary parameters that impact the self-healing process, including varied pre-strain levels of 1%, 2%, and 4.3% for SMA wires, are investigated. The outcomes of these pre-strain levels are subsequently compared to the repair scenario in the absence of SMAs. The transferred healing agent volume to the damaged region and the remaining crack opening is quantified using a thermography camera and image processing techniques. The study’s results demonstrate that self-healing can be achieved through strategic considerations of pre-strain levels in SMA strings and loading modes. Furthermore, the study suggests that neglecting such concerns may potentially have deleterious effects on layered samples' load-bearing capacity. The proposed methodology holds great promise for producing self-healing 3D-printed composite specimens in the laboratory and scaling them up to real-world applications.

Diagnostic accuracy for CZT gamma camera compared to conventional gamma camera technique with myocardial perfusion single-photon emission computed tomography: Assessment of myocardial infarction and function

BackgroundThe solid-state cadmium-zinc-telluride (CZT) gamma camera for myocardial perfusion single-photon emission computed tomography (MPS) has theoretical advantages compared to the conventional gamma camera technique. This includes more sensitive detectors and better energy resolution. We aimed to explore the diagnostic performance of gated MPS with a CZT gamma camera compared to a conventional gamma camera for detection of myocardial infarct (MI) and assessment of left ventricular (LV) volumes and ejection fraction (LVEF), using cardiac magnetic resonance (CMR) as the reference method. MethodsSeventy-three patients (26% female) with known or suspected chronic coronary syndrome were examined with gated MPS using both a CZT gamma camera and a conventional gamma camera as well as with CMR. Presence and extent of MI on MPS and late gadolinium enhancement (LGE) CMR was evaluated. For LV volumes, LVEF and LV mass, gated MPS images and cine CMR images were evaluated. ResultsMI was found in 42 patients on CMR. The overall sensitivity, specificity, positive and negative predictive values for the CZT and the conventional gamma camera were the same (67%, 100%, 100% and 69%). For infarct size > 3% on CMR, the sensitivity was 82% for the CZT and 73% for the conventional gamma camera, respectively. LV volumes were significantly underestimated by MPS compared to CMR (P ≤ .002 for all measures). The underestimation was slightly less pronounced for the CZT compared to the conventional gamma camera (2-10 mL, P ≤ .03 for all measures). For LVEF, however, accuracy was high for both gamma cameras. ConclusionDifferences between a CZT and a conventional gamma camera for detection of MI and assessment of LV volumes and LVEF are small and do not appear to be clinically significant.

CINEMATOGRAPHY IN GABRIELE MUCCINO’S THE PURSUIT OF HAPPINESS (2006)

This study aimed to study cinematography elements presented in Gabriele Muccino’s The Pursuit of Happiness (2006). To analyse the object of the research, it used cinematography theory by Blain Brown. The study used descriptive qualitative research design. Drama genre is one of the biggest and popular genre in the movie industry, since it shares some empathy, hopes, aspirations, dreams and fears (Editors, 2018). It focused on analysing the dramatic aspect through cinematography using Gabriele Muccino’s The Pursuit of Happiness (2006) movie. The study found that many cinematography elements in Gabriele Muccino’s The Pursuit of Happiness (2006) are proven using dramatic aspect from both lighting and camera technique. In conclusion, the movie shows a drama genre movie which has cinematography elements that need to be added to deliver the emotion of the story and to increase dramatic elements in the movie. Keywords: cinematography, genre, drama

Hero Shots: The Hero Myth as a Visual Frame in American Television Coverage of Lance Armstrong

A camera technique known among sports broadcasters as a “hero shot” is used to capture the moment the athlete has successfully completed the task that seals or celebrates a victory. However, the “hero shot” and its components have not been examined in a scholarly setting. The current study aims to build a theoretical understanding of the “hero shot” as a visual frame that conveys hero mythology. The authors used the hero mythology literature and Brooklyn College's film department film glossary to determine which distance, angles, content, and means were most often used to capture heroic imagery of former American professional cyclist Lance Armstrong. This was done through a content analysis of 927 individual shots of Armstrong, aired between 1999 and 2010. Results suggest that low-angle and long shots were most commonly used for “hero shots.” However, the prominence of three-shots suggests the importance of other actors in contextualizing the hero.

K-POP IDOL STANDARD DAN PRAKTIK KOMODIFIKASI PEKERJA DALAM VIDEO CLIP “IU-CELEBRITY”

K-pop idols are demanded by agencies and fans based on beauty standards, ideal bodies, how to dress, and self-image. This study aims to describe the forms of K-pop idol standards and the practice of commodifying workers in the video clip “IU – Celebrity.” The Political Economy Theory of Communication from Vincent Mosco is used to see the practice of commodification, using John Fiske's Semiotics analysis method. The results of this study, on: (1) the level of reality, a k-pop idol is required to meet the ideal standards based on the agency as well as fan's wants; (2) representation level, signs at the reality level are transmitted into representational codes such as camera techniques, angles, transitions, video editing, location sets, sound, to special fx; (3) ideological level, it is found that there are capitalistic practices through the commodification of workers towards k-pop idols by the agency in the form of regulating appearance standards, clothing, privacy, and social relations of k-pop idols. This is done by the agency in order to maintain their idol image in accordance with the wishes of fans.

Thermal oxidation and compressive failure behavior of ZrSi2–B4C modified phenolic resin-based composite

Phenolic resin-based ablative materials have gained significant attention in the aerospace sector in recent years. In this study, TGA-DSC, FT-IR, XRD and XPS were employed to the thermal stability and phase transformation of the ZrSi2–B4C modified quartz fiber/boron containing phenolic resin (QF/BPR) composite. The compressive failure behavior of the composite at 600–1200 °C was studied through SEM and high-speed camera techniques. The results indicated that the compression strength of the composite decreased to a minimum at 600 °C and increased at 800–1200 °C. The composite exhibited different failure modes at different temperature: shear fracture at room temperature (RT), debonding of the fiber bundles at 600 °C, fiber buckling and fiber shear fracture at 800 °C, fiber buckling and delamination at 1000–1200 °C. The improvement in thermal stability of composite was primarily attributed to the formation of ZrO2, SiO2 and B2O3, which covered the fiber and effectively transmitted the load, leading to an enhanced strength of the interface between the fiber and resin.

Interactivity and Ecomedia in the Digital Age

Interactivity is a fundamental aspect of contemporary digital media and communication, playing a crucial role in the synergistic relationship between filmic representation and video games. This paper examines the interplay between Jeta Amata's eco-film Black November and the video game Niger Delta Commando, focusing on the narratives, themes, and imaginary worlds that define their relationship. In the context of Nigeria's Niger Delta challenges, these media forms provide alternative approaches for addressing environmental issues while maintaining relevance and competing for attention in the entertainment landscape. Nigeria's rapidly growing video game industry holds significant potential for entertainment and economic development. This study acknowledges the integral part played by film in influencing the development of video games, as both mediums share aspects such as camera techniques, narrative structures, visual representation technologies, special effects, and thematic concerns. In this case, Niger Delta Commando allows players to determine the narrative through interactivity, offering a unique and innovative way to address the Niger Delta's environmental challenges. Adopting a dual analytical and descriptive methodology, this paper explores the interrelatedness of the narratives linking Black November and Niger Delta Commando, reconciling leading arguments in ecomedia, and assessing the Nigerian narrative's notions of interactivity, immersion, and environment. The analysis also considers the environmental impacts of media product life cycles and addresses the differential experiences of affected populations. The eco-film Black November is recreated in the interactive video game medium Niger Delta Commando, emphasizing the military action storyline and visual style reminiscent of the Niger Delta region's activist struggles. However, the video game primarily adopts an action-thriller plot without addressing the underlying factors contributing to violence in the region or the environmental degradation detailed in Black November. Media products, including films and video games, have demonstrated their utility as tools for engaging with and analyzing human concerns. With video games becoming increasingly popular and accepted as an artistic medium, adaptations like Niger Delta Commando can provide more immersive representations of environmental issues. The paper proposes that future video games addressing the Niger Delta region should feature complex and nuanced intersections reflecting the region's ecological challenges, moving beyond violence and towards a more constructive engagement with the environment.

Computer Vision System for Facial Palsy Detection

Facial palsy (FP) is a disorder that affects the seventh facial nerve, which makes the patient unable to control facial movements and expressions with other vital activities. It affects one side of the face, and it is usually diagnosed by the asymmetry of the two sides of the face through visual inspection by a doctor. However, the visual inspection is human-based, which is prone to errors because the doctor is exposed to omission due to fatigue and work stress. Therefore, it is important to develop a new method for detecting FP through artificial intelligence and use a more accurate computerized system to reduce the effort and cost of patients and increase the accuracy of diagnosis. This work aims to establish a safe, useful and high-accuracy diagnostic system for FP that can be used by the patient and proposes to detect FP using a digital camera and deep learning techniques automatically. The system could be used by the patient himself at home without needing to visit the hospital. The proposed system trained 570 images, including 200 images of FP palsy. The proposed FP system achieved an accuracy of 98%. This confirms the effectiveness of the proposed system and makes it an efficient medical examination tool for detecting FP.

Analisis Semiotika John Fiske terhadap Representasi Kedekatan Emosional Orang Tua dan Anak Dalam Film “Pulang”

Emotional closeness is fundamental in a harmonious family which is often implemented with interaction between parents and children, but interaction is not always the main thing but behavior, habits, touch or physical contact also greatly affect emotional closeness. This study aims to explore the form of emotional closeness that is formed between parents and children in the film ‘Pulang’, the theme of the film is family conflict which focuses on Pras (Ringgo Agus) and Rindu (Ziva Magnolya) during their trip to Jogjakarta. By using John Fiske's semiotic analysis with its three levels, the research results can be presented in the form of a representation of emotional closeness at the level of reality which is confirmed through dynamic interactions, freedom of expression and gestures as a form of care and affection. The level representation highlighted in the camera technique (shots) has shown signs at the level of reality as evidenced by the interactions between the characters. The ideological level found is Liberalism which is applied in parenting, education and early child development by parents in influencing emotional closeness. Then the form of emotional closeness that is formed is a secure attachment pattern that constructs a high emotional reality closeness to the characters Pras and Rindu.
 Keywords: Emotional Closeness; Interaction; Semiotic; Liberalism

Mixed mode I/II fracture behavior and surface morphology of hard rock under dynamic loading

To investigate the dynamic mixed mode I/II fracture properties of hard rock, split-Hopkinson pressure bar (SHPB) was utilized to conduct dynamic fracture tests on cracked straight through Brazilian disc (CSTBD) diorite specimens with different mode mixities. The dynamic fracture load and fracture toughness for different crack angles or mode mixities were determined. The dynamic fracture process and crack mouth opening displacement (CMOD) of CSTBD specimens were monitored by high-speed camera and digital image correlation (DIC) technique, and the fractal and morphology characteristics of fracture surfaces were further analyzed using laser 3D scanner and scanning electron microscope (SEM). The test results indicate that the dynamic CMOD behavior is interrelated closely to the force acting on the crack surface, and the allowable CMOD corresponding to the dynamic peak load decreases with increasing crack angle. In addition, the stress-based and strain-based fracture criteria were introduced to analyze the mixed mode fracture mechanism of diorite. It is found that the GMTS criterion with small fracture process zone (FPZ) size and the EMTSN criterion have the best prediction effect for fracture toughness and crack initiation angle respectively. Observation results show that the macro fracture trajectories of primary cracks and secondary cracks are controlled by the prefabricated crack angle, while the variation in mode mixity has little impact on the meso-roughness and micro-morphology of the fracture surface. The fracture surface of CSTBD diorite specimen under dynamic load exhibits the SEM morphology features of mixed tensile-shear cracks.

Mat Kilau Kebangkitan Pahlawan: A Cognitive Study Through Freytag’s Drama Structure

The popularity of film storylines that glorify heroes fighting for their nation has spread throughout Malaysia. This advancement has increased the income of the country's creative industry while also improving the talents of creative professionals. Due to the high level of competition, special effects, shooting techniques, and even storytelling processing are the primary factors employed in enhancing a film's success. Using Freytag's Pyramid, the film Mat Kilau is a case study to identify students' knowledge of the film's narrative and camera skills and techniques. Open-ended questionnaires were delivered to 37 students in free-form written responses to obtain a wealth of information about how the respondents think and relate to what they have learnt over the semester. The content analysis measures how often certain words, subjects, and ideas appear in a text. The approach turns qualitative input into quantitative data to draw accurate conclusions about what people thought of the movie. In this study, the data suggest that students pay more attention to sequences with many sound effects, different forms of camera tracking, and rapid shot changes. The selection of students who felt the best scene served as the film's Climax is observed.

Experimental and numerical simulation on the sliding process of roof rock blocks triggered by dynamic disturbance

With the excavation of underground opening, the roof rock block may fall under external dynamic disturbance. In this paper, the roof rock mass was simplified as a rock block system composed of trapezoidal rock blocks. A series of experiments and numerical simulations were performed to study the sliding process of the key block under the horizontal static clamping load and vertical impact disturbance. The propagation of stress wave in the block system were captured and analyzed by using high-speed camera and digital image correlation technique. The results reveal that a pendulum-type wave was generated due to the propagation and superposition of stress waves in the block system. Therefore, the governing mechanism of the sliding displacement of the key block was clarified based on the propagation of incident stress waves or pendulum-type waves. Meanwhile, it is found that the sliding distance of the key block decreases in a power function with the increasing friction coefficient, or decreases in a parabolic function with the increasing trapezoid internal angle. Finally, a case study on the roof block sliding of the roadway at a gold mine was conducted, and it is concluded that the sliding of the key block resulted from the coupled effects of “shear driving” and “low friction” driven by stress wave propagation, regardless of a single or multi-layer rock block system. These results may provide technical guideline for preventing rock-falling accidents caused by blasting disturbances in underground mining.

An optical flow-based method for condition-based maintenance and operational safety in autonomous cleaning robots

Autonomous professional cleaning robots are ubiquitous today, coexist with humans, and the demand continues to improve hygiene and productivity, especially in large indoor workplaces. Hence, a proper maintenance strategy is essential to monitor the robot’s health, assuring flawless operation and safety. Manual supervision and periodic maintenance are adopted in general, which is challenging to detect failures in advance, resulting in higher maintenance costs and operational hazards. Anomalous vibration due to system degradation or environmental factors is an early symptom of failure or potential threats. Hence, predicting the sources of such abnormal vibration will help prompt maintenance action or set a hazard-free environment. However, such condition-monitoring research studies are not common for indoor cleaning robots. To fill this gap, we proposed an automated Condition Monitoring (CM) system, predicting the abnormal vibration sources that will enhance Condition-based Maintenance (CbM) and Operational Safety. A novel vibration-based CM method is presented for mobile robots, suitable for indoor environments under typical illumination states, using a monocular camera and optical flow technique instead of their usual perception-related applications. The sources of abnormal vibration were classified as terrain, collision, loose assembly, and structural imbalance. We modelled vibration as sparse optical flow, and the change in optical flow vector displacement due to the robot’s vibration is derived from consecutive camera frames used as vibration data. A practical framework is developed adopting the One Dimensional Convolutional Neural Network (1D CNN) model to fit this vibration data and tested predicting the vibration source class with an average accuracy of 93.8%. In addition, a vibration source map (CbM map) is proposed by fusing the predicted class in the workplace environment map for real-time monitoring. The case studies conducted using our in-house-developed cleaning robot show that the proposed CM framework will help the maintenance team for CbM, operational safety, and select proper maintenance strategies.

The effect of flaw geometry and infilling on crack initiation, propagation, and coalescence of a parallel flaw pair in marble

A series of uniaxial compression tests were conducted on unfilled or filled marble specimens with a parallel flaw pair to study the effect of the flaw geometry and infilling on the crack coalescence pattern. Special attention was paid to the crack initiation, propagation, and coalescence processes, which were traced by the CCD camera and digital image correlation (DIC) technique. The experimental results have shown that the appearance of the white patch and strain localization band precedes the initiation of macroscopic crack. The tensile crack evolves from a narrow strain band or white patches with clear boundaries, while the shear crack evolves from a wider strain band or white patch with blurry boundaries. The high-strength fillers suppress the initiation and propagation of the tensile cracks (i.e., T1, T2, and T3) and promote the appearance of the coplanar shear cracks and mixed tensile-shear cracks (i.e., M1, M2, and S1). The variation in the infilling condition leads to the difference in the fundamental crack types, hence resulting in different coalescence patterns for a given flaw geometry. For small rock bridge angles (i.e., β = 30°, 45°), no coalescence and indirect coalescence tends to occur between the open and gypsum-filled flaws, while shear coalescence is prone to occur between the cement- and resin-filled flaws. The coalescence patterns are dominated by the flaw geometry for medium rock bridge angles (i.e., β = 60°, 90°), but the crack coalescence stress and peak strength of specimens are greatly affected by the infilling conditions. For large rock bridge angle (i.e., β = 120°), the increase in the strength of the filler tends to generate straighter wing cracks for the tensile coalescence at the rock bridge and promotes the initiation of mixed tensile-shear cracks for additional coalescence outside the rock bridge.

Biomass Origin Waste as Activators of the Polyurethane Foaming Process

Rigid polyurethane foams (RPUFs) are characterized by their excellent viable properties; thus, these materials can be successfully used as thermal insulation materials. The main problem, the solution of which is partly indicated in this paper, is that the products for the synthesis of RPUFs are produced from petrochemicals. Due to this, the use of natural fillers in the form of waste biomass is introduced for the synthesis of RPUFs. The biodegradable biomass waste used in the RPUF production process plays multiple roles: it becomes an activator of the RPUF foaming process, improves selected properties of RPUF materials and reduces the production costs of insulating materials. The paper presents the results of the foaming process with the use of six different fillers: sunflower husk (SH), rice husk (RH), buckwheat husk (BH), sunflower husk ash (SHA), rice husk ash (RHA) and buckwheat husk ash (BHA). In all cases, composites of rigid polyurethane foam with 10 wt.% of filler were produced. New foams were compared with polyurethane materials without the addition of a modifier. Moreover, the paper presents the results of the fillers’ analysis used in the tests and the effects of the fillers’ addition as activators of the RPUF foaming process. Promising results were obtained for two of the fillers, BHA and SHA, as activators of the foaming process and confirmed by the volumetric results, where the named samples reached their maximum value in half the time compared to the remaining samples. In addition, the expansion rate for PU_10BHA was a maximum of approximately 11 cm3/s and PU_10SHA was a maximum of approximately 9 cm3/s, whereas the remaining samples showed this parameter at about 3 cm3/s. During the research, the scanning electron microscopy method and infrared camera technique were used.

Displacement and Extinction of Jet Diffusion Flame Exposed to Speaker-Generated Traveling Sound Waves

Acoustic flame suppression is a potential technology which does away with the need to carry fire-extinguishing media and does not cause secondary pollution. We herein reported an experimental study on the displacement and extinction of jet diffusion flames exposed to speaker-generated traveling sound waves with a frequency of 110–150 Hz and local sound pressure of 2–16 Pa. The simultaneous movement of the flame and fuel was captured using a high-speed camera and schlieren techniques. Results showed that the flame oscillation was dominated by induced wind produced by membrane vibrations instead of sound pressure, and this induced wind’s frequency was the same as that of sound waves. Moreover, the movement of unburned fuel and flame was not synchronous, which resulted in an interrupted fuel–flame cycle. Consequently, the flame was gradually suppressed and completely extinguished after several oscillation cycles. Finally, we determined the extinction criterion that when the dimensionless gap between the flame and the unburned fuel was greater than or equal to 7, the flame would be extinguished. Results clearly revealed the mechanism of acoustic fire extinguishing, which provided reference for the feasibility of acoustic fire-extinguishing applications.

Embedded PZT aggregates for monitoring crack growth and predicting surface crack in reinforced concrete beam

This study proposed an approach to monitor the cracks growth process of reinforced concrete beam using embedded piezoelectric aggregates. The principle of stress waves propagation in concrete cracks was analyzed, and a damage index was introduced to estimate the crack damage degree in concrete structure on this basis. A stepwise loading was applied to the reinforced concrete beam, and it was divided into three areas according to the different force conditions. Moreover, the piezoelectric aggregates were fabricated, and four aggregates were embedded into the specimen to monitor its each area by active monitoring technique. The results of the experiment demonstrated that the proposed damage index could realize the dynamic monitoring and damage degree evaluation of the specimen. Furthermore, this index could forecast the occurrence of surface crack and warn the collapse of the structure in advance. The proposed method was also verified by high-speed camera and image processing technique.

A STUDY ON THE USAGE OF CAMERA TECHNIQUES FOR COMMUNICATION IN CINEMA (WITH SPECIAL REFERENCE TO MRINAL SEN’S BHUVAN SHOME)

Communication is one of the most important parts of human life. We cannot live without communicating with each other. There are many forms and mediums of communication among which cinema is considered one of the most important modes of communication. Not only this it also has the power to influence the mass and bring about some changes in the society. It has the power to shape the mind of people and give them a new direction in life. Films are made in many different spoken languages, but cinema has its own visual language as well. Camera techniques are one of them. A lot is conveyed through cameras in movies which at times even dialogues cannot convey. The camera is not just used to record the act done by the actors, but it is the bridge between the audience and the performers which helps to connect them to each other. Using camera techniques in a way which leaves a good and long impact over the mind of the audience is difficult and only good directors gave the capability of doing so. When we watch any movie, we are taken into the journey of characters by the director and camera plays the role of a vehicle which helps us to go on this journey. Thus, camera can be considered not just equipment but a tool for making the story telling process more interesting and the process of communication more impactful.

Experimental investigation of the microlayer and dry spot dynamic characteristics in a small channel flow boiling by laser interferometry method

It is well established that the microlayer beneath the bubble plays a pivotal effect in the heat transfer in nucleation boiling. However, experimental studies of microlayers in small channel flow boiling are scarce due to measurement difficulty. In this study, laser interferometry and high-speed camera techniques were used simultaneously to investigate the microlayer dynamic characteristics beneath boiling bubbles in a small channel. It is found that the microlayer's interference fringe is still not a complete "Newtonian ring" in small horizontal channels. The downstream of the bubble, the microlayer still shows a "wedge" structure, and the initial microlayer thickness distribution is similar to that of the pool boiling. The microlayer is not entirely evaporated, and the rewetting phenomenon occurs simultaneously with the evaporation of the microlayer. The newly dry spot area and the rewetting area show the characteristics of first increasing to a maximum and then decreasing.

Global hip-hop culture and the scopophilic spectacle of women in South African hip-hop music videos

In many hip-hop music videos, women’s value is reduced to sensuous display of sexuality. Asa result visual pleasure is created through the representation of women as eager and willingsexual objects. This article assesses the techniques and ways women are sexualised in SouthAfrican hip-hop music videos, and how their representation attempts to create visual pleasurefor those that consume these videos. Four critical elements are adopted from Laura Mulvey’sseminal theoretical discourse about the positioning of women in narrative cinema, to study thegender representation and sexual presentation of women in two popular South African hip-hopmusic videos. The analysis reveals that appealing to the male gaze, processes of objectification,gender division of labour and camera techniques are ways of presenting a sexualised spectacleof women for the visual pleasure of male characters and audiences of the videos.