Journal of Mechanical Engineering, Automation and Control Systems
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Höegh LNG and Altera Infrastructure is scaling up large scale CCS infrastructure
Get PDFIn a joint initiative, called “Stella Maris CCS” Altera Infrastructure and Höegh LNG are working together to provide cost efficient floating Carbon Capture and Storage infrastructure solutions for a global market, not limited to size or geographical location. Valuable infrastructure experience is brought together; with FPSO (Floating Production, Storage and Offloading) and Dynamically Positioned Shuttle Tankers from Altera and FSRU’s (Floating Storage Regasification Unit) from Höegh. We intend to continue to build on our heritage and experience, using our combined skills to contribute to carbon emission reduction around globe. With the “Stella Maris CCS” project, we will essentially be doing what we are doing today, only in reverse. Our solution, initiated in 2019 as the first of its kind, will offer a large-scale floating infrastructure for collection, transport, and injection of CO2 into subsea reservoirs/aquifers. Our infrastructure concept consists of 2-3 Carbon Collection Storage Units (CCSU) to aggregate volumes at different key locations, 3-4 CO2 Shuttle Carriers and one Floating Storage and Injection Unit, the total amount of CO2 injected with these assets can reach up to 10 million tons per year. In order to realize large scale CCS, the unit costs must come down, and the barriers for emitting industries to invest in capture plants must be lowered. With Stella Maris we are addressing these hurdles. The larger ship design enables carrying volumes of CO2 at low pressure and will allow for greater economies of scale in the absence of a pipeline which places less limitations on distance to reservoir and ultimate flow capacity. Having a centralized conditioning of CO2 in a CCSO hub allows more flexibility for on-site capture design from multiple onshore industrial emission sources with shared port access. To defray high logistics cost in e.g. the Baltic region, a hub and spoke transportation approach enables collection in smaller parcels, milk-run gathering and conditioning for large scale transfer for storage in an offshore subsea reservoir on the Norwegian Continental shelf
Corporeal-composition indicators, and physiological alterations in dental eruption
Get PDFWorldwide, obesity leads to major diseases in adults. Infants are affected as well, particularly because of growth and development issues. In this article we describe cases of early dental eruption in overweight and obese children, almost 1 year earlier than expected. The relations and mechanisms that cause these alterations remain to be determined
Experimental investigation of bi-modular material coating to enhance damping
Get PDFHard coatings can be used to increase damping when applied on the surface of the components of turbomachinery. This can be effective to reduce the resonant vibration level of components working in a high cycle fatigue environment due to the extremely high operational speed. This paper discusses the experimental investigation of a bi-modular material hard coating to enhance damping in structural steel elements. Firstly, a hard coating (Al2O3+MgO) is applied on AISI 304L stainless steel substrate by plasma spraying. After that, a layer of chrome is deposited by chrome plating. Dynamic responses of both coated and uncoated samples are measured. The damping ratio of the test specimen is extracted from the time response by the logarithmic decrement method. Improved damping capacity of the coated steel sample is observed and is mainly attributed to the thin coating of chrome on the steel structure. The natural frequency of coated specimen showed 8 to 10 % improvement, the forced response showed a 30 to 35 % decrement in displacement, the damping ratio showed a 200 % increment, and the time of decaying showed a 20 % decrement. The results of the present study provide new ideas for the development of high-damping structural elements
Bifurcation analysis of fractional duffing system based on improved short memory principle method
Get PDFIn this paper, the dynamic characteristics of fractional Duffing system are analyzed and studied by using the improved short memory principle method. This method has small amount of calculation and high precision, and can effectively improve the problem of large amount of calculation caused by the memory of fractional order. The influence of frequency change on the dynamic performance of the fractional Duffing system is studied using nonlinear dynamic analysis methods, such as Phase Portrait, Poincare Map and Bifurcation Diagram. Moreover, the dynamic behaviour of the fractional Duffing system when the fractional order and excitation amplitude changes are investigated. The analysis shows that when the excitation frequency changes from 0.43 to 1.22, the bifurcation diagram contains four periodic and three chaotic motion regions. Periodic motion windows are found in the three chaotic motion regions. It is confirmed that the frequency and amplitude of the external excitation and the fractional order of damping have a greater impact on system dynamics. Thus, attention shall be paid to the design and analysis of system dynamics
Greensand project – transport and offshore storage of CO2 in Denmark – status, outlook and challenges
Get PDFThe Greensand project includes, beside from safe and efficient geological offshore CO2 storage, offshore transport by ship and/or pipeline of CO2 from key side onshore facilities established to capture, liquefy, onshore transport and temporarily store the CO2 before offloading to storage site. The Greensand project builds on the usage of the offshore Siri complex sandstone reservoirs no longer in use for oil and gas production. The storage sites, offloading and injection systems and transportation means are currently being technically matured. The target is to be able to offer customers safe and reliable transport and storage services from the start of 2026. Currently meanwhile maturing a technical concept, commercial and regulatory activities are ongoing in parallel. The Greensand partners INEOS Energy and Wintershall Dea have also decided to perform an offshore pilot test of injecting liquified CO2 into a particular reservoir serving as candidate for future long terms storage of CO2. Along the pilot testing offshore project, material testing and deployment of monitoring techniques are being matured. The Pilot testing offshore planned to take place late 2022 with a 3-months duration
Skull base flexion and its influence on chewing
Get PDFSkull base asymmetries can occur in the intrauterine period, manifesting from birth as craniofacial asymmetries and should be investigated both in the maxilla and mandible and in the craniofacial region, as they are related to the base of the skull. The objective of this study was to explain that treatment using Craniofacial Biodynamics (CFBD) enables symmetrical craniofacial growth, being recommended from three to six years of age, when the processes of skull base remodeling cease. This study was based on exploratory bibliographic research, aiming at a better understanding of the concepts presented in this therapeutic approach, to verify the influence that such concepts exert on treatment through CFBD. It was evidenced in this research that these asymmetries may be corrected, or even minimized through the CFBD, which relates the ontogenetic development of the skull base with orofacial development
Treatment of vertical problems with jaw functional orthopedics based on scientific evidence. Part 1: anterior open bite
Get PDFThe vertical problems of the stomatognathic system that alter the overbite, either by increasing in the deep bite (DB) or decreasing in the anterior open bite (AOB), are among the great challenges of the dentofacial corrections in the treatment and the retention and stability protocols. It is always good to report that a correct diagnosis is fundamental in the choice of treatment protocol and that skeletal involvement, be it hyper divergence in case of open bite or hypo divergence in case of deep bite, aggravates the problem and as a rule tends to increase treatment and containment time. In this paper the state of art of AOB treatment with Jaw Functional Orthopedics (JFO) will be discussed. It should be emphasized that JFO has a unique diagnostic tool for changes in vertical growth of the face, the Articular Compass, developed by Simões. Studies show that the use of treatment protocols developed by Simões, the SNs (SN2, SN3, SN6) act in the increase of overbite efficiently (P= 0.003) in cases of open bite. This is weak evidence, due to the design of the study, but with promising results, so Randomized Clinical Trials are needed to investigate if these results are replicable
Functional orthopedic device type Sn20 – a therapeutic resource in the control of chronic temporomandibular dysfunction – case report
Get PDFThe literature indicates that patients with a history of Temporomandibular Disorder (TMD), who experience sudden occlusal changes, may worsen their parafunctional habits and develop TMD again. In this sense, the aim of this study is to present a clinical case of recurrent chronic TMD after oral rehabilitation (increase of vertical dimension in all teeth) using Simões Network 20 (SN20) functional orthopedic appliance as one of the resources therapies. The patient was female, 62 years old, and complained of disabling pain, anxiety symptoms, hypervigilant and history of TMD. The patient reported failure of other treatment modalities, including use of the smooth stabilizer device. The diagnosis was chronic TMD – primary osteoarthritis of the temporomandibular joint and related myofascial pain and orofacial migraine. Treatment included physical measurements, instructions, peripheral and central medication, AOF type SN20 (night use). After three months of therapy, the patient showed significant improvement with complete pain reduction. The use of the AOF SN20 together with conservative measures represents a valuable therapeutic modality for patients with chronic TMD
The influence of the truss bar on the dynamic behavior of a Warren truss by changing the modulus of elasticity
Get PDFThe paper presents the natural frequencies shift of a Warren truss with seven elements in the case that members of the structure are weakened by considering that the modulus of elasticity with a lower value. Taking into consideration that the slenderness ratio has a constant value and the transverse section of the truss bars is changed, the relative frequency shift for the first seven vibration mode were calculated by using the values obtained from numerical modal analysis. The conclusions reveal the fact from the dynamic behavior of the structure it can be obtained templates to identify the weakened truss bar of the structure
Modal analysis of a milling dynamometer considered as 1DOF system
Get PDFA force transducer-based plate dynamometer for milling force measurements is presented in this paper. The main components of the designed dynamometer were described, and experimental modal analysis was carried out while considering the dynamometer as a 1DOF system. The values of the main components of the 1DOF systems such as mass, damping coefficient, and equivalent stiffness were identified, and the natural frequency for rings and dynamometer was calculated. The calculated natural frequencies of components were found in reacceptance FRF, obtained by modal analysis done with an impact hammer. A MATLAB simulation was done to validate the system using the transfer function based on the modal test