Unique Design Research Articles

Bearing Fault Diagnosis Method Based on Adversarial Transfer Learning for Imbalanced Samples of Portal Crane Drive Motor

Due to their unique structural design, portal cranes have been extensively utilized in bulk cargo and container terminals. The bearing fault of their drive motors is a critical issue that significantly impacts their operational efficiency. Moreover, the problem of imbalanced fault samples has a more pronounced influence on the application of novel fault diagnosis methods. To address this, the paper presents a new method called bidirectional gated recurrent domain adversarial transfer learning (BRDATL), specifically designed for imbalanced samples from portal cranes’ drive motor bearings. Initially, a bidirectional gated recurrent unit (Bi-GRU) is used as a feature extractor within the network to comprehensively extract features from both source and target domains. Building on this, a new Correlation Maximum Mean Discrepancy (CAMMD) method, integrating both Correlation Alignment (CORAL) and Maximum Mean Discrepancy (MMD), is proposed to guide the feature generator in providing domain-invariant features. Considering the real-time data characteristics of portal crane drive motor bearings, we adjusted the CWRU and XJTU-SY bearing datasets and conducted comparative experiments. The experimental results show that the accuracy of the proposed method is up to 99.5%, which is obviously higher than other methods. The presented fault diagnosis model provides a practical and theoretical framework for diagnosing faults in portal cranes’ field operation environments.

Skin‐Like Transparent, High Resilience, Low Hysteresis, Fatigue‐Resistant Cellulose‐Based Eutectogel for Self‐Powered E‐Skin and Human–Machine Interaction

AbstractArtificial electronic skin (E‐skin), a class of promising materials mimicking the physical‐chemical and sensory performance of the human skin, has gained extensive interest in the field of human health‐monitoring and robotic skins. However, developing E‐skin simultaneously achieving high resilience, hysteresis‐free, and absent external power is always a formidable challenge. Herein, a liquid‐free eutectic gel‐based self‐powered E‐skin with high resilience, fatigue resistance, and conductivity is prepared by introducing hydroxypropyl cellulose (HPC) into metal salt‐based deep eutectic solvents (MDES). The unique structural design of cellulose‐anchored permanent entangled poly(acrylic acid) (PAA) chain, in combination with rapid broken/reconstruction of the dense dynamic sacrificial bonds, realizes the fabrication of high‐elastic E‐skin with negligible hysteresis. This further demonstrates the promising practical application of the cellulose‐based eutectogel with high transmittance (92%), high conductivity (36.6 mS m−1), and high resilience (98.1%), and excellent environment stability in robust triboelectric nanogenerator for energy harvesting and high resilience, self‐powered E‐skin for human health‐caring and human‐machine interaction.

Understanding the Continuance Intention of College Students toward New E-Learning Spaces Based on an Integrated Model of the TAM and TTF

The emergence of educational video platforms has led to microlearning resources becoming increasingly mainstream. These platforms offer unique ecosystems and resource designs that better cater to the needs of learners. In this study, we examined the technology acceptance model (TAM) and task-technology fit (TTF) theory and conducted an empirical analysis of user satisfaction with new online learning spaces. We learned that perceived usefulness, perceived ease of use, and task-technology fit had significantly impacted user satisfaction, with these three factors collectively contributing to 78.2% of the variance in user satisfaction. Additionally, user satisfaction and task-technology fit significantly influenced the continuance intentions of users toward using these spaces, with both factors contributing to 66.7% of the variance in continuance intention. Overall, our findings revealed that the future development of new online learning spaces should consider the task requirements of learners and improve the platforms accordingly.

Coumarin-Conjugated Macromolecular Probe for Sequential Stimuli-Mediated Activation.

Protein bioconjugation has emerged as one of the most valuable tools for the development of protein-based biochemical assays. Here, we report a fluorescent macromolecular material, RF16_Halo, in which the coumarin derivative RF16 is specifically conjugated onto HaloTag protein to achieve a dual-stimuli-mediated fluorescence response. RF16 is first obtained by installing a H2O2-sensitive boron cage onto the C7 hydroxy moiety of the coumarin fluorophore with a HaloTag ligand attaching to the pH-labile 1,3-dioxane moiety. Upon stimulation, RF16_Halo exhibits a sequential fluorescence response to H2O2/pH at both liquid and solid interfaces. The fluorescence of the RF16_Halo-based protein film increases linearly toward H2O2 with a higher sensitivity when compared with that of RF16. Subsequently, the H2O2-cleaved RF16_Halo presents a pH-dependent fluorescence decrease under acidic conditions. Such a stimulus-responsive fluorescence "off-on-off" multimode enables RF16_Halo to be applied as a sequential logic circuit. In addition, we evaluate the fluorescence labeling ability of RF16 to intracellular IRE1_Halo protein and demonstrate that RF16 containing the HaloTag ligand could be precisely retained in cells to track IRE1_Halo protein. Hence, we provide a unique structural design strategy to construct a fluorescence dual-responsive macromolecular probe for information encryption and protein tracking in cells.

Quantum modelling of multi-directional fused-ring electron acceptors for organic photovoltaics

Multi-directional fused-ring electron acceptors (FREAs) feature a fused-ring backbone that extends in multiple directions through bridging and acceptor units. This unique structural design imparts several advantageous properties, like increased light absorption, precise energy level adjustments, improved electron mobility, reduced energy loss, and enhanced efficiency in organic photovoltaic (OPV) devices. In this study, we designed seven novel multi-directional FREAs and conducted a comprehensive computational analysis using Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT). The designed molecules feature a benzotrithienopyrrole central core connected to a π-bridge acceptor, either benzothiadiazole or benzotriazole, and three varying terminal acceptors, including malononitrile, 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile, and 2-(3-methyl-4-oxothiazolidin-2-ylidene)malononitrile. Our investigation encompassed the evaluation of geometry, frontier molecular orbitals (FMOs), optical properties, density of states (DOS), charge mobilities, dipole moment, global reactivity descriptors, molecular electrostatic potential (MEP), transition density matrix (TDM), and OPV device-related parameters. The results revealed significant potential of the designed molecules as FREAs for OPVs, thus highlighting their suitability for further experimental exploration.

Forward Security with Crash Recovery for Secure Logs

Logging is a key mechanism in the security of computer systems. Beyond supporting important forward security properties, it is critical that logging withstands both failures and intentional tampering to prevent subtle attacks leaving the system in an inconsistent state with inconclusive evidence. We propose new techniques combining forward security with crash recovery for secure log data storage. As the support of specifically forward integrity and the online nature of logging prevent the use of conventional coding, we propose and analyze a coding scheme resolving these unique design constraints. Specifically, our coding enables forward integrity, online encoding, and most importantly a constant number of operations per encoding. It adds a new log item by 𝖷𝖮𝖱 ing it to k cells of a table. If up to a certain threshold of cells is modified by the adversary, or lost due to a crash, we still guarantee recovery of all stored log items. The main advantage of the coding scheme is its efficiency and compatibility with forward integrity. The key contribution of the paper is the use of spectral graph theory techniques to prove that k is constant in the number n of all log items ever stored and small in practice, e.g., k = 5. Moreover, we prove that to cope with up to \(\sqrt {n}\) modified or lost log items, storage expansion is constant in n and small in practice. For k = 5, the size of the table is only 12% more than the simple concatenation of all n items. We propose and evaluate original techniques to scale the computation cost of recovery to several GBytes of security logs. We instantiate our scheme into an abstract data structure which allows to either detect adversarial modifications to log items or treat modifications like data loss in a system crash. The data structure can recover lost log items, thereby effectively reverting adversarial modifications.

Robotic Heller's myotomy using the new Hugo™ RAS system: first worldwide report.

Achalasia is a rare disorder of the esophagus characterized by motor dysfunction in the esophagus and relaxation failure of the lower esophageal sphincter (LES). Currently, surgical myotomy procedures are considered the standard of care. Robotic Heller's myotomy (RHM) with fundoplication has been gaining popularity due to documented advantages in the precision of myotomy as well as avoiding the potential reflux following per-oral endoscopic myotomy (POEM). To the best of our knowledge, RHM has thus far has been performed exclusively by the da Vinci surgical system. The new Hugo RAS™ system offers a unique modular design and an open console which offers better maneuverability and docking options. In this study, we present the first worldwide series of patients undergoing RHM using the new Hugo RAS™ platform. Our objective is to propose optimal operating configuration and setup to fully harness the advantages of the unique modular design of this system. Ten consecutive achalasia patients underwent Robotic Heller's myotomy (RHM) with the Hugo RAS™ system. We prospectively collected patient data, including demographics, comorbidities, ASA class, Eckardt scores, pre-operative manometric data, and EndoFlip parameters. Additionally, we recorded the docking and total operative times. Between December 2022 and August 2023, 10 patients underwent RHM with the Hugo™ RAS system. Patients had a median age of 42.5 years, 60% were female, and mean BMI was 23.2. Fifty percent had achalasia type 2 and 50% type 1. The median pre-operative integrated relaxation pressure (IRP) was 24.9. Median docking time was 10 min and overall operative time was 129.5 min. All patients, except one with acute coronary syndrome, had an uneventful peri-operative course and were discharged on post-operative day 2. The Hugo™ RAS system is well designed for robotic Heller myotomy. The operative and clinical results are similar to the currently used robotic system; however, the modular design of the system has some differences. These translate to better docking angles and maneuverability as well as console surgeon's ergonomics. Further experience is needed to explore the advantages of the system's modular design and function.

Honeycomb substrate carbon and nitrogen-doped coated carbon synergistically boost SnS/ZnS for efficient lithium storage

Metal sulfide has become an important anode electrode material for lithium-ion batteries due to its high theoretical specific capacity and low cost. In this work, nano-SnS/ZnS grown on a honeycomb substrate carbon were coated with nitrogen-doped carbon (EG@SnS@ZnS@N-C) by solvothermal and in situ thermal decomposition/sulfide reactions. Honeycomb carbon with good electrical conductivity and mechanical mechanism is loaded with SnS and ZnS with synergistic effects, combined with nitrogen-doped porous carbon with enhanced ion transport. These unique designs enable EG@SnS@ZnS@N-C to exhibit excellent lithium storage performance with a specific capacity of 880 mAh/g at 0.1 A/g and capacity retention of 98% after 100 cycles.

Evaluating the potential of wind and solar energy in achieving zero energy ratings in residential homes: A Nottingham case study

This research explores the potential for reducing reliance on fossil fuels through the combined utilisation of photovoltaic energy and local Vertical Axis Wind Turbines (VAWTs). In urban settings, VAWTs offer advantages such as lower noise emissions, independence from wind direction, operational efficiency at both low and high wind speeds, and enhanced stability due to their unique helical blade design. These characteristics make VAWTs a suitable and effective option for generating sustainable energy in urban environments. A Vertical Axis Wind Turbine (VAWT) will be virtually introduced to 2050 Homes Development in Nottingham, a cluster of 27 houses configured to use a micro–Low Temperature District Heating (LTDH) network.This paper investigates the possibility to move 2050 Homes scheme into zero energy level by using Quite Revolution (QR6) helical blade VAWT along with photovoltaic energy generation. The preliminary results show that two QR6 VAWT can bring the 27 terrace homes from the 2050 Homes scheme into zero energy class performance.

Enhancing polarization maintenance and spectral filtering in negative curvature hollow-core fibers

A new design of polarization-maintaining and spectral filtering negative curvature hollow-core fiber tailored for the telecommunication bands in the near-infrared region is presented. The optical fiber, consisting of a six-tube silica structure, incorporates vertically nested tubes anchored radially by a pole structure. By contrast, standard nested tubes in the horizontal direction form the asymmetric fiber structure, which encounters birefringence. This unique fiber design not only preserves the polarization states of light but also exhibits frequency selective transmission exclusively in the vertical direction due to the pole structure. Through fiber design optimization, a transmission loss below 0.1 dB/km for spectrally filtered wavelengths is achieved, with birefringence on the order of 10−5 within the wavelength range of 1.45 µm to 1.60 µm. These results demonstrate significant improvements in terms of birefringence, distinct loss separation between horizontally and vertically polarized states, and a reduced number of spectrally filtered wavelengths compared to previously reported findings. The proposed fiber design holds untapped potential for applications requiring selective transmissions with specific polarization.

Energy Extraction System for the Superconductive Solenoid with Current 5100 A and Stored Energy 22 MJ

At the FAIR (Facility for Antiproton and Ion Research, Darmstadt, Germany) accelerator complex under construction, one of the key experiments is the PANDA experiment. The main field of the PANDA spectrometer is provided by a superconducting solenoid. The energy of the magnetic field stored in a superconducting solenoid reaches 22 MJ at an operating current of 5100 A. In the case of the transition of the superconducting cable used for the solenoid winding into a resistive state, the safe extraction of stored energy is required to protect the magnet. The energy extraction system proposed by the authors provides energy dissipation inside the external dump resistor, and not in the section of the superconducting cable that has passed into resistive state, while preventing its damage. The most critical elements of the energy extraction system are the current breaker, with the help of which the dump resistor is introduced into the power circuit of the superconducting solenoid, and the dump resistor itself. A modernized three-phase circuit breaker was chosen as current breaker. A unique design of the energy extraction system including dump resistor with a low parasitic inductance has been developed.

Subversion and PersistenceAnalysis of Balenciaga's Innovation Strategy

Balenciaga is a world-renowned luxury brand, and its unique design style and profound historical background make its position in fashion unshakable. However, like all innovators, Balenciagas design style is not always understood and accepted by people. This paper will discuss how Balenciaga maintains its influence in the world fashion through subversive innovation and continuous innovation, and analyze peoples different reactions to its innovative design. The author will deeply analyze and understand the history, design philosophy and specific works of Balenciaga. At the same time, we will combine personal observation and experience to evaluate its innovative way and influence. Balenciagas innovation is mainly manifested in subversive innovation and continuous innovation. It redefines fashion by breaking the tradition, while maintaining its unique brand identity and design concept. Although some of Balenciagas designs may be regarded as ugly in the eyes of the public, it is the embodiment of its innovative spirit and the source of its lasting influence in the fashion world.

Mental, physical, and social well-being and quality of life in healthy young adult twin pairs discordant and concordant for body mass index.

The relationship between obesity and mental health is complex and is moderated by the level of obesity, age, sex, and social and genetic factors. In the current study, we used a unique co-twin control design, with twin pairs discordant for body mass index (BMI), to control for shared genetic and environmental effects between obesity and several dimensions of mental health. We studied 74 monozygotic (MZ) twin pairs, of whom 36 were BMI-discordant (intra-pair difference in BMI ≥ 3 kg/m2), and 77 dizygotic (DZ) twin pairs (46 BMI-discordant). We assessed subjective health, especially mental health and mental well-being (depression, anxiety, self-esteem, health-related quality of life, life satisfaction, and social well-being) through questionnaires. Heavier MZ co-twins from BMI-discordant pairs had poorer general health (58.8±3.0 vs. 72.4±3.8, P = 0.001, FDR = 0.017 on a scale from 0 to 100 where higher scores indicate more positive results), physical functioning (90.3±1.1 vs. 95.5±2.2, P = 0.024, FDR = 0.122), energy levels (55.6±3.4 vs. 66.6±3.3, P = 0.013, FDR = 0.109), and emotional well-being (65.9±3.2 vs. 75.4±2.9, P = 0.031, FDR = 0.122), as well as a tendency for depressive symptoms (8.4±1.3 vs. 5.6±0.9, P = 0.071, FDR = 0.166) compared to their leaner co-twins. Heavier DZ co-twins had poorer total physical well-being (91.6±1.9 vs. 95.6±1.0, P = 0.035, FDR = 0.356) and more depressive symptoms (4.3±0.9 vs. 2.4±0.5, P = 0.016, FDR = 0.345 on a scale from 0 to 63 where lower scores indicate fewer depressive symptoms) than their leaner co-twins. Association analyses, using all twin pairs, confirmed that higher BMI within pairs linked to general health, physical functioning and depressive symptoms. No association was found between BMI and anxiety, self-esteem, life satisfaction, or social well-being. In conclusion, this study underscores the notable association between elevated BMI and physical well-being and to a lesser extent between elevated BMI and depressive symptoms, while revealing no discernible connections with anxiety, self-esteem, life satisfaction, or social well-being.

Thermal management of an asymmetrical wavy microchannel heat sink via Ag/water nanofluid

The ever-increasing demand for electronic systems to enhance their performance and processing speed has exponentially increased their heat generation, especially those containing microstructures with reduced surface area. Tackling these complex thermal management challenges creates an urgent need to design and model compact efficient cooling systems. In this investigation, a unique design of a microchannel heat sink with sinusoidal and absolute sinusoidal wavy walls with/without nanofluid is proposed. Heat transfer enhancement and fluid flow characteristics are numerically investigated by developing a two-dimensional finite element model for Reynolds numbers 5, 100, and 500. The periodicity of the wavy section and the different volume fractions of silver nanoparticles ranging from 0 to 4% in water are further considered. The entropy generation is analyzed using the Bejan number. The findings revealed that while the entropy generation rises in the absolute sinusoidal channel, it has a better heat transfer performance by 10.3%, 15.8%, and 16.6% than a straight microchannel for the ascending Reynolds numbers. Interestingly, the channel's heat transfer and thermal efficiency decrease when an unnecessary number of sinusoidal periods are used. The thermal efficiency improves by 3.35% compared to the straight microchannel by employing only one absolute sinusoidal wavelength along the channel.

Engineering Kirigami Frameworks Toward Real-World Applications.

The surge in advanced manufacturing techniques has led to a paradigm shift in the realm of material design from developing completely new chemistry to tailoring geometry within existing materials. Kirigami, evolved from a traditional cultural and artistic craft of cutting and folding, has emerged as a powerful framework that endows simple 2D sheets with unique mechanical, thermal, optical, and acoustic properties, as well as shape-shifting capabilities. Given its flexibility, versatility, and ease of fabrication, there are significant efforts in developing kirigami algorithms to create various architectured materials for a wide range of applications. This review summarizes the fundamental mechanisms that govern the transformation of kirigami structures and elucidates how these mechanisms contribute to their distinctive properties, including high stretchability and adaptability, tunable surface topography, programmable shape morphing, and characteristics of bistability and multistability. It then highlights several promising applications enabled by the unique kirigami designs and concludes with an outlook on the future challenges and perspectives of kirigami-inspired metamaterials toward real-worldapplications.

Generation of Multiple Concentration Gradients Using a Two-Dimensional Pyramid Array.

Concentration heterogeneity of diffusible reactants is a prevalent phenomenon in biochemical processes, requiring the generation of concentration gradients for the relevant experiments. In this study, we present a high-density pyramid array microfluidic network for the effective and precise generation of multiple concentration gradients. The complex gradient distribution in the 2D array can be adaptively adjusted by modulating the reactant velocities and concentrations at the inlets. In addition, the unique design of each reaction chamber and mixing block in the array ensures uniform concentrations within each chamber during dynamic changes, enabling large-scale reactions with low reactant volumes. Through detailed numerical simulation of mass transport within the complex microchannel networks, the proposed method allows researchers to determine the desired number of reaction chambers within a given concentration range based on experimental requirements and to quickly obtain the operating conditions with the help of machine learning-based prediction. The effectiveness in generating a multiple concentration gradient environment was further demonstrated by concentration-dependent calcium carbonate crystallization experiments. This device provides a highly efficient mixing and adaptable concentration platform that is well suited for high-throughput and multiplexed reactions.

Longitudinal AD biomarkers in monozygotic twins: genetic contribution to AD biomarker concentrations over time

AbstractBackgroundUnderstanding the earliest pathophysiological changes in Alzheimer’s disease (AD) is important for development of therapeutic intervention strategies. Studying genetically identical twins provides unique information on genetic and environmental influences on development of AD. Here we studied change in AD biomarkers amyloid β1‐42 (aβ42), amyloid β1‐40 (aβ40), phosphorylated tau181 (p‐tau) and total tau (t‐tau) in CSF over time in a cohort of older cognitively normal monozygotic twins and tested the genetic contribution to biomarker concentrations at baseline and to change of biomarker concentrations over time.MethodWe included 103 twins (npairs = 42) from the EMIF‐AD preclinAD study with 2‐4 repeated CSF sampling available across a time period of 4.47±2 years (mean±SD age: 68.8±7 years, 54 (52%) female). We measured aβ42, aβ40, p‐tau and t‐tau using the Lumipulse platform (Fujirebio Diagnostics, Inc.). We used linear mixed models to investigate change in biomarker concentrations over time. We used twin‐pair intraclass correlation (ICC) analysis to estimate the genetic contribution to biomarker concentrations at baseline and at repeated measurements, and to annual change in biomarker concentrations.ResultAt baseline, 25 (24%) individuals had an abnormal aβ42/aβ40 ratio, 27 (26%) abnormal p‐tau and 35 (34%) abnormal t‐tau, and at last measurement respectively 34 (33%), 38 (37%) and 45 (44%). Across the group, aβ42/aβ40 decreased (β±SE ‐0.001±0, p‐value<0.001), and p‐tau and t‐tau increased over time (respectively 1.37±0.3, p‐value<0.001; 6.58±2.3, p‐value = 0.004). Increases in p‐tau levels were most pronounced in amyloid positive individuals (2.72±0.38, p‐value<0.001) compared to amyloid negative individuals (0.65±0.24, p‐value = 0.007; p‐value interaction<0.001). At baseline, the genetic contribution to biomarker concentrations was lowest for t‐tau (ICC = 0.5, p<0.001) and highest for aβ40 (ICC = 0.79, p<0.001). ICC’s remained similar at repeated measurements (table 1). Annual changes of aβ40 and p‐tau showed significant twin‐pair correlations (resp. ICC’s: 0.58 and 0.42; p‐values <0.01; Figure 1), indicating a genetic contribution to change in these concentrations over time.ConclusionIn this sample of older cognitively normal monozygotic twins, we found that AD biomarkers became increasingly abnormal over time. Our unique twin design further indicates that these very early pathophysiological changes are under moderate to high genetic influence, which also indicates a role of environmental factors.

Reduced pace of biological aging explains the association of diet with dementia: results from the Framingham Offspring Study

AbstractBackgroundSubstantial evidence supports the benefice of healthy diet for brain aging; however, the underlying pathways remain largely unknown. Leveraging a unique cohort design with assessment of long‐term dietary habits, DNA methylation data, and 10‐year follow‐up for dementia, we evaluated the mediating role of pace of biological aging on the relationship of diet with dementia. We investigated the specificity of this pathway for brain aging, as compared to overall aging, by investigating the same mediation for the risk of all‐cause mortality.MethodWe included 1,644 participants (≥60 years‐old) from the Framingham Offspring Cohort, who were free of dementia at baseline examination (exam 8 [2005‐2008]). We evaluated long‐term adherence to a Mediterranean diet (MeDi) by averaging dietary scores across four assessments (validated food frequency questionnaire at exams 5 [1991‐1995], 6 [1995‐1998], 7 [1998‐2001], and 8). Using DNA methylation data collected at baseline, we measured the pace of biological aging through the DunedinPACE epigenetic clock, which was the DNA methylation measure the most strongly associated with dementia in prior studies. Incidence of dementia and mortality was adjudicated from baseline until 2018 by expert committees. We performed mediation analyses to estimate the role of pace of biological aging on the relationship between diet and dementia or all‐cause mortality.ResultOver the follow‐up (maximum, 13.8 years), 140 (8.5%) participants developed dementia, and 471 (28.6%) died. Participants with a higher adherence to MeDi had a slower pace of biological aging, and lower risks of dementia and of all‐cause mortality (Figure). A faster pace of aging was associated with increased risks of dementia and mortality. Biological aging mediated 13% [95% CI, 0.06; 0.43] of the association between diet and dementia, and 43% [0.23; 1.08] of the association of diet with mortality.ConclusionPart of the association of healthier diet with lower risk of dementia is mediated by a slowing of global processes of biological aging. However, this pathway does not fully explain the association of diet and dementia and the proportion mediated was three times smaller than what was observed for mortality, suggesting that other mechanisms, especially brain‐specific mechanisms, need to be further described.

Indigenization of Buoy Components Using Additive Manufacturing Technique

The Ocean Observation Systems (OOS) group of the National Institute of Ocean Technology (NIOT) is involved in the design, development and sustenance of moored data buoys in the Indian Seas. The moored buoy systems deployed in the Northern Indian Ocean provide real-time, continuous observation of surface meteorological and oceanographic parameters which help in monitoring extreme weather events and natural disasters such as cyclones and tsunamis. Buoy components are of different sizes and shapes and are made of various materials, including metals and plastics. However, due to unique and critical design requirements, the development of deep-sea components faces hurdles caused by manufacturing limitations. The advent of additive manufacturing (AM) has met the demand for quickly producing parts. Due to the high pressure and low temperature conditions, it is extremely difficult to design and develop deep sea components. Consequently, High Impact Polystyrene (HIPS) material has been selected for the subsurface floats. The float is manufactured using the Fused Deposition Modeling (FDM) additive manufacturing technique in the Fabheads 1K FDM printer with pellet based extrusion method. These subsurface floats are used at a water depth of 500 m in NIOT buoy systems, with a working pressure of approximately 50 bar. Taking a factor of safety of two into account, the part is designed to withstand 100 bar. To assess the component's performance under deep-sea hydrostatic conditions, it underwent testing in the hyperbaric chamber test facility at NIOT. During the qualification process, the component successfully withstood the design pressure of 100 bar and imploded at 102 bar. This study is part of NIOT's ongoing efforts to indigenize deep-sea components using AM and assess its future prospects.

Methods for Improving the Quality of Forgings and Blanks Obtained by Forging through Intensifying Shear or Alternating Strain in the Bulk of Deformable Metal

The article presents methods for improving the quality of forgings and workpieces obtained by forging by intensifying shear or alternating strain in the bulk of the deformed metal. To increase the metal processing due to shear or alternating strain during forging, forging strikers are most often used, the feature of which is the geometric configuration that creates additional metal flows. Quite a lot of works from research teams from all over the world have been devoted to the problem of intensive metal processing during forging. In these publications, a number of new unique designs of strikers have been proposed and various route technologies have been considered, which can significantly increase the level of shear or alternating strain compared with the use of traditional forging tool designs.