Search results for: single skin curtain wall

Authors: Masoud Mahdavi, Mojtaba Farzaneh Moghadam

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The seismic forces caused by the waves created in the depths of the earth during the earthquake hit the structure and cause the building to vibrate. Creating large seismic forces will cause low-strength sections in the structure to suffer extensive surface damage. The use of new steel shear walls in steel structures has caused the strength of the building and its main members (columns) to increase due to the reduction and depreciation of seismic forces during earthquakes. In the present study, an attempt was made to evaluate a type of steel shear wall that has regular holes in the inner sheet by modeling the finite element model with Abacus software. The shear wall of the steel plate, measuring 6000 × 3000 mm (one floor) and 3 mm thickness, was modeled with four different pores with a cross-sectional area. The shear wall was dynamically subjected to a time history of 5 seconds by three accelerators, El Centro, Imperial Valley and Kobe. The results showed that increasing the distance between the geometric center of the hole and the geometric center of the inner plate in the steel shear wall (increasing the R_CS index) caused the total maximum acceleration to be transferred from the perimeter of the hole to horizontal and vertical beams. The results also show that there is no direct relationship between R_CS index and total acceleration in steel shear wall and R_CS index is separate from the peak ground acceleration value of earthquake.

Keywords: hollow steel plate shear wall, time history analysis, finite element method, abaqus software

Procedia PDF Downloads 102

Authors: Mahmoud Roushdy, Mohamed El Naggar, Ahmed Yehia Abdelaziz

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Anchored sheet pile has been used worldwide as front quay walls for decades. With the increase in vessel drafts and weights, those sheet pile walls need to be upgraded by increasing the depth of the dredging line in front of the wall. A system has recently been used to increase the depth in front of the wall by installing a separated platform supported on a deep foundation (so called Relieving Platform) behind the sheet pile wall. The platform is structurally separated from the front wall. This paper presents a numerical investigation utilizing finite element analysis on the behavior of separated relieve platforms installed within existing anchored sheet pile quay walls. The investigation was done in two steps: a verification step followed by a parametric study. In the verification step, the numerical model was verified based on field measurements performed by others. The validated model was extended within the parametric study to a series of models with different backfill soils, separation gap width, and number of pile rows supporting the platform. The results of the numerical investigation show that using stiff clay as backfill soil (neglecting consolidation) gives better performance for the front wall and the first pile row adjacent to sandy backfills. The degree of compaction of the sandy backfill slightly increases lateral deformations but reduces bending moment acting on pile rows, while the effect is minor on the front wall. In addition, the increase in the separation gap width gradually increases bending moments on the front wall regardless of the backfill soil type, while this effect is reversed on pile rows (gradually decrease). Finally, the paper studies the possibility of reducing the number of pile rows along with the separation to take advantage of the positive separation effect on piles.

Keywords: anchored sheet pile, relieving platform, separation gap, upgrade quay wall

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Authors: N. H. Hamid, N. M. Mohamed, S. A. Anuar

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Precast residential houses are normally constructed in Malaysia using precast shear-key wall panel and precast wall panel are designed using BS8110 where there is no provision for earthquake. However, the safety of this house under moderate and strong earthquake is still questionable. Consequently, the full-scale of residential house are designed, constructed, tested and analyzed under in-plane lateral cyclic loading. Hysteresis loops are plotted based on the experimental work and compared with modeling of hysteresis loops using HYSTERES in RUAUMOKO 2D program. Modified Takeda hysteresis model is chosen to behave a similar pattern with experimental work. This program will display the earthquake excitations, spectral displacements, pseudo spectral acceleration, and deformation shape of the structure. It can be concluded that this building is suffering severe cracks and damage under moderate and severe earthquake.

Keywords: precast shear-key, hysteresis loops, spectral displacements, deformation shape

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Authors: Sunghyun Kim, Hong-Gun Park

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In the performance-based design (PBD), by using the nonlinear dynamic analysis (NDA), the actual performance of the structure is evaluated. Unlike frame structures, in the wall structures, base shear force which is resulted from the NDA, is greatly amplified than that from the elastic analysis. This shear amplifying effect causes repeated designs which make designer difficult to apply the PBD. Therefore, in this paper, factors which affect shear amplification were studied. For the 20-story wall model, the NDA was performed. From the analysis results, the base shear amplification factor was proposed.

Keywords: performance based design, shear amplification factor, nonlinear dynamic analysis, RC shear wall

Procedia PDF Downloads 378

Authors: Ahmed A. Khamis, Sherif A. Ibrahim, Mahmoud El Khatieb, Mohamed A. Barakat

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Parametric design is an icon of the modern architectural that facilitate taking complex design decisions counting on altering various design parameters. Double skin facades are one of the parametric applications for using parametric designs. This paper opts to enhance different daylight parameters of a selected case study office building in Cairo using parametric double skin facade. First, the design and optimization process executed utilizing Grasshopper parametric design software which is a plugin in rhino. The daylighting performance of the base case building model was compared with the one used the double façade showing an enhancement in daylighting performance indicators like glare and task illuminance in the modified model, execution drawings are made for the optimized design to be executed through Revit, followed by computerized digital fabrication stages of the designed model with various scales to reach the final design decisions using Simplify 3D for mock-up digital fabrication

Keywords: parametric design, double skin facades, digital fabrication, grasshopper, simplify 3D

Procedia PDF Downloads 118

Authors: Amin Eslami, Jafar Bolouri Bazaz

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Under active stress conditions, a rigid cantilever retaining wall tends to rotate about a pivot point located within the embedded depth of the wall. For purely granular and cohesive soils, a methodology was previously reported called minimization of moment ratio to determine the location of the pivot point of rotation. The usage of this new methodology is to estimate the rotational stability safety factor. Moreover, the degree of improvement required in a backfill to get a desired safety factor can be estimated by the concept of the shear strength demand. In this article, the accuracy of this method for another type of cantilever walls called Contiguous Bored Pile (CBP) retaining wall is evaluated by using physical modeling technique. Based on observations, the results of moment ratio minimization method are in good agreement with the results of the carried out physical modeling.

Keywords: cantilever retaining wall, physical modeling, minimization of moment ratio method, pivot point

Procedia PDF Downloads 331

Authors: Ashwin Bala, K. Panthalaraja Kumaran, S. Prithviraj, R. Pradeep, J. Udhayakumar, S. Ajith

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In this paper, studies have been carried out for an in-house design of a waste heat recovery system for effectively utilizing the domestic air conditioner heat energy for producing hot water. Theoretical studies have been carried to optimizing the flow rate for getting maximum output with a minimum size of the heater. Critical diameter, wall thickness, and total length of the water pipeline have been estimated from the conventional heat transfer model. Several combinations of pipeline shapes viz., spiral, coil, zigzag wound through the radiator has been attempted and accordingly shape has been optimized using heat transfer analyses. The initial condition is declared based on the water flow rate and temperature. Through the parametric analytical studies we have conjectured that water flow rate, temperature difference between incoming water and radiator skin temperature, pipe material, radiator material, geometry of the water pipe viz., length, diameter, and wall thickness are having bearing on the lucrative design of a waste heat recovery system for air conditioners. Results generated through the numerical studies have been validated using an in-house waste heat recovery system for air conditioners.

Keywords: air conditioner design, energy conversion system, radiator design for energy recovery systems, waste heat recovery system

Procedia PDF Downloads 357

Authors: Marcin Jakiel, Maria Kurek, Karolina Gutkowska, Sylwia Sanakiewicz, Dominika Stolarczyk, Jakub Batko, Rafał Jakiel, Mateusz K. Hołda

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The geometry of RVOT is extremely complicated. It is an irregular block with an ellipsoidal cross-section, whose dimensions decrease toward the pulmonary valve and measure 33.82 (IQR 30,51-39,36), 28.82 (IQR 26,11-32,22), 27.95 ± 4,11 for width [mm] and 33.41 ± 6,14, 26.99 ± 4,41, 26.91 ± 4,00 [mm] for depth, in the basal, middle and subpulmonary parts, respectively. In a sagittal section view, the RVOT heads upward and slightly backward. Its anterior perimeter has an average length of 41.96 mm and inclines to the transverse plane at an angle of 50.77° (IQR 46,53°-58,70°). In the posterior region, the RVOT is shorter (18.17mm) and flexes anteriorly. Therefore, the slope of the upper part of the rear wall to the transverse plane is an acute angle (open toward the rear) of 44,58° (IQR 37,30°-51,25°), while in the lower part it is an angle close to a right angle of 94,30°±15,44°. In addition, the thickness of the RVOT wall in the diastolic phase, at the posterior perimeter at the base, in the middle of the length and subpulmonary measure 3,80 mm ± 0,88 mm, 3,56 mm ± 0,73 mm, 3,56 mm ± 0,65 mm, respectively. In frontal cross-section, the RVOT rises on the interventricular septum, which makes it possible to distinguish the septal and supraseptal parts on its left periphery. The angles (facing the vertices to the right) of the inclination of these parts to the transverse plane are 75.5° (IQR 66,44°-81,11°) and 107.01° (IQR 99,09 – 115,23°), respectively, which allows us to conclude that the direction of the RVOT long axis changes from left to right. The above analysis shows that there is no single RVOT axis. Two axes can be distinguished, the one for the upper RVOT being more backward and leftward. The aforementioned forward deflection of the posterior wall and the RVOT's elevation over the interventricular septum, suggest that access to the subpulmonary region may be difficult. It should be emphasized that this area is often the target for ablation of ventricular arrhythmias. The small thickness of the RVOT posterior wall, with its difficult geometry, may favor its perforation into the pericardium or ascending aorta.

Keywords: angle, geometry, operation access, position, RVOT, shape

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Authors: H. Barati, M. Wu, A. Kharicha, A. Ludwig

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A transient model for nozzle clogging has been developed and successfully validated against a laboratory experiment. Key steps of clogging are considered: transport of particles by turbulent flow towards the nozzle wall; interactions between fluid flow and nozzle wall, and the adhesion of the particle on the wall; the growth of the clog layer and its interaction with the flow. The current paper is to investigate the mesh (size and type) sensitivity of the model in both two and three dimensions. It is found that the algorithm for clog growth alone excluding the flow effect is insensitive to the mesh type and size, but the calculation including flow becomes sensitive to the mesh quality. The use of 2D meshes leads to overestimation of the clog growth because the 3D nature of flow in the boundary layer cannot be properly solved by 2D calculation. 3D simulation with tetrahedron mesh can also lead to an error estimation of the clog growth. A mesh-independent result can be achieved with hexahedral mesh, or at least with triangular prism (inflation layer) for near-wall regions.

Keywords: clogging, continuous casting, inclusion, simulation, submerged entry nozzle

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Authors: Yazid Alkraimeen

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Precise prediction of dielectric stresses and high voltages of power transformers require the accurate calculation of frequency-dependent parameters. A lack of accuracy can result in severe damages to transformer windings. Transient conditions is stuided by digital computers, which require the implementation of accurate models. This paper analyzes the computation of frequency-dependent skin and proximity losses included in the transformer winding model, using analytical equations and Finite Element Method (FEM). A modified formula to calculate the proximity and the skin losses is presented. The results of the frequency-dependent parameter calculations are verified using the Finite Element Method. The time-domain transient voltages are obtained using Numerical Inverse Laplace Transform. The results show that the classical formula for proximity losses is overestimating the transient voltages when compared with the results obtained from the modified method on a simple transformer geometry.

Keywords: fast front transients, proximity losses, transformer winding modeling, skin losses

Procedia PDF Downloads 139

Authors: Daniela F. Maluf, Fernanda Roters, Luma C. F. Silva

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The goal of this work is to report the main dermatological alterations occurring during pregnancy and actual cosmetic protocols available and recommended for safe use. Throughout pregnancy, woman's body undergoes many transformations such as hormonal changes and weight gain. These alterations can result in undesirable skin aspects that end up affecting the future mother's life. The main complaints of pregnant women involve melasma advent, varicose veins, edema, and natural skin aging. Even if most of the time is recommended to wait for the birth to use cosmetics, there are some alternatives to prevent and to treat these alterations during pregnancy. For all these cases, there is a need to update information about safety and efficacy of new actives and technologies in cosmetic products. The purpose of this study was to conduct a literature review about the main skin alterations during pregnancy and actual recommended treatments, according to the current legislation.

Keywords: pregnancy, cosmetic, treatment, physiological changes

Procedia PDF Downloads 364

Authors: Kritin K. Verma, Brian L. Ransdell

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White patches are a symptom of vitiligo, a chronic autoimmune dermatological condition that causes a loss of pigmentation in the skin. Vitiligo can cause issues of self-esteem and quality of life while also progressing the development of other autoimmune diseases. Current treatments in allopathy and homeopathy exist; some treatments have been found to be toxic, whereas others have been helpful. Allopathy has seemed to offer several treatment plans, such as phototherapy, skin lightening preparations, immunosuppressive drugs, combined modality therapy, and steroid medications to improve vitiligo. This presentation will review the FDA-approved topical cream, Opzelura, a JAK inhibitor, and its effects on limiting vitiligo progression. Meanwhile, other non-conventional methods, such as Arsenic Sulphuratum Flavum used in homeopathy, will be debunked based on current literature. Most treatments still serve to arrest progression and induce skin repigmentation. Treatment plans may differ between patients due to depigmentation location on the skin. Since there is no gold standard plan for treating patients with vitiligo, the oral presentation will review all topical and systemic pharmacological therapies that fight the depigmentation of the skin and categorize their validity from a systematic review of the literature. Since treatment plans are limited in nature, all treatment methods will be mentioned and an attempt will be made to make a golden standard treatment process for these patients.

Keywords: vitiligo, phototherapy, immunosuppressive drugs, skin lightening preparations, combined modality therapy, arsenic sulphuratum flavum, homeopathy, allopathy, golden standard, Opzelura

Procedia PDF Downloads 86

Authors: Pratistha Shrestha

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Background: Acrochordons (Skin tags) are common benign skin tumors usually occurring on the neck and major flexors of older people. These range in size from 1 mm to 1cm in diameter and are skin-colored or brownish. A possible association with diabetes mellitus has been suggested in previous studies, but the result is not conclusive. Objective: The aim of this study was to find out the association of diabetes mellitus with acrochordons. Material and Methods: One hundred and two patients were selected for the study. Among them, 51 (males–23 and females–28) with acrochordons were taken as cases, and 51 with other dermatologic diseases after matching age and sex were taken as controls. The patients were selected from OPD of the Department of Dermatology and Venereology in Universal College of Medical Sciences–Teaching Hospital (UCMS-TH). Blood glucose levels, including both fasting plasma glucose and 2-hour post-glucose load, were determined for both case and control and compared. Results: Patients with acrochordons had a significantly higher frequency of diabetes than the control group (p < 0.001). A total of 48.5% and 40% of patients with acrochordons having diabetes were obese and overweight, respectively. Conclusion: There is an increased risk of diabetes mellitus in patients with acrochordons. With regard to the importance of early diagnosis of diabetes, it is recommended a high level of suspicion for diabetes mellitus in patients with acrochordons.

Keywords: acrochordons, diabetes mellitus, obesity, skin tags

Procedia PDF Downloads 155

Authors: Mandy W. M. Chan, Samantha Y. N. Shek, Chi K. Yeung, Taro Kono, Henry H. L. Chan

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Fractional radiofrequency devices have shown to improve skin texture such as smoothness, rhytides, brightness as well as atrophic acne scars by increasing dermal thickness, dermal collagen content and dermal fibrillin content. The objective of the study is to assess the efficacy and adverse effects of this device on Asian patients with skin textural changes. In this study, 20 Chinese patients (ranging from 21-60 years old) with irregularities of skin texture, rhytides and acne scars were recruited. Patients received six treatments at 2-4 week intervals. Treatment was initiated with maximum energy tolerated and was adjustable during treatment if patients felt excessive discomfort. A total of two passes were delivered at each session. Physician assessment and standardized photographs were taken at baseline, all treatment visits and at one, two, and six month after final treatment. As a result, 17 patients were recruited and completed the study according to the study protocol. One patient withdrew after the first treatment due to reaction to local anesthesia and two patients were lost to follow-up. At six months follow-up, 71% of the patients were satisfied and 24% were very satisfied, while treatment physician reported various degrees of improvement based on the global assessment scale in 60% of the subjects. Anticipated side effects including erythema, edema, pinpoint bleeding, scabs formation and flare of acne were recorded, but there were no serious adverse effects noted. Conclude up, the use of fractional radiofrequency improves skin texture and appears to be safe in Asian patients. No long-term serious adverse effect was noted.

Keywords: Asian, fractional radiogrequency, skin, texture

Procedia PDF Downloads 145

Authors: Elif Tugce Aksun Tumerkan, Umran Cansu, Gokhan Boran, Fatih Ozogul

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Gelatin is a mixture of peptides obtained from collagen by partial thermal hydrolysis. It is an important and useful biopolymer that is used in the food, pharmacy, and photography products. Generally, gelatins are sourced from pig skin and bones, beef bone and hide, but within the last decade, using alternative gelatin resources has attracted some interest. In this study, functional properties of gelatin extracted from seafood and poultry by-products were evaluated. For this purpose, skins of skipjack tuna (Katsuwonus pelamis) and frog (Rana esculata) were used as seafood by-products and chicken skin as poultry by-product as raw material for gelatin extraction. Following the extraction of gelatin, all samples were lyophilized and stored in plastic bags at room temperature. For comparing gelatins obtained; chemical composition, common quality parameters including bloom value, gel strength, and viscosity in addition to some others like melting and gelling temperatures, hydroxyproline content, and colorimetric parameters were determined. The results showed that the highest protein content obtained in frog gelatin with 90.1% and the highest hydroxyproline content was in chicken gelatin with 7.6% value. Frog gelatin showed a significantly higher (P < 0.05) melting point (42.7°C) compared to that of fish (29.7°C) and chicken (29.7°C) gelatins. The bloom value of gelatin from frog skin was found higher (363 g) than chicken and fish gelatins (352 and 336 g, respectively) (P < 0.05). While fish gelatin had higher lightness (L*) value (92.64) compared to chicken and frog gelatins, redness/greenness (a*) value was significantly higher in frog skin gelatin. Based on the results obtained, it can be concluded that skins of different animals with high commercial value may be utilized as alternative sources to produce gelatin with high yield and desirable functional properties. Functional and quality analysis of gelatin from frog, chicken, and tuna skin showed by-product of poultry and seafood can be used as an alternative gelatine source to mammalian gelatine. The functional properties, including bloom strength, melting points, and viscosity of gelatin from frog skin were more admirable than that of the chicken and tuna skin. Among gelatin groups, significant characteristic differences such as gel strength and physicochemical properties were observed based on not only raw material but also the extraction method.

Keywords: chicken skin, fish skin, food industry, frog skin, gel strength

Procedia PDF Downloads 163

Authors: Minakshi Mainaji Sonawane, Bharti W. Gawali, Sudhir Mendhekar, Ramesh R. Manza

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People's lives and health are severely impacted by skin diseases. A new study proposes an effective method for identifying the different forms of skin diseases. Image denoising is a technique for improving image quality after it has been harmed by noise. The proposed technique is based on the usage of the wavelet transform. Wavelet transform is the best method for analyzing the image due to the ability to split the image into the sub-band, which has been used to estimate the noise ratio at the noisy image. According to experimental results, the proposed method presents the best values for MSE, PSNR, and Entropy for denoised images. we can found in Also, by using different types of wavelet transform filters is make the proposed approach can obtain the best results 23.13, 20.08, 50.7 for the image denoising process

Keywords: MSE, PSNR, entropy, Gaussian filter, DWT

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Authors: Kavitha A.S., L.Govindaraju

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Reinforced earth walls offer excellent solution to many problems associated with earth retaining structures especially under seismic conditions. Use of cohesive soils as backfill material reduces the cost of reinforced soil walls if proper drainage measures are taken. This paper presents a numerical study on the application of a new technique called sandwich technique in reinforced earth walls. In this technique, a thin layer of granular soil is placed above and below the reinforcement layer to initiate interface friction and the remaining portion of the backfill is filled up using the existing insitu cohesive soil. A 6 m high reinforced earth wall has been analysed as a two-dimensional plane strain finite element model. Three types of reinforcing elements such as geotextile, geogrid and metallic strips were used. The horizontal wall displacements and the tensile loads in the reinforcement were used as the criteria to evaluate the results at the end of construction and dynamic excitation phases. Also to verify the effectiveness of sandwich layer on the performance of the wall, the thickness of sand fill surrounding the reinforcement was varied. At the end of construction stage it is found that the wall with sandwich type backfill yielded lower displacements when compared to the wall with cohesive soil as backfill. Also with sandwich backfill, the reinforcement loads reduced substantially when compared to the wall with cohesive soil as backfill. Further, it is found that sandwich technique as backfill and geogrid as reinforcement is a good combination to reduce the deformations of geosynthetic reinforced walls during seismic loading.

Keywords: geogrid, geotextile, reinforced earth, sandwich technique

Procedia PDF Downloads 287

Authors: Anja I. Petrov, Milica B. Veljković, Marija M. Ćorović, Ana D. Milivojević, Milica B. Simović, Katarina M. Banjanac, Dejan I. Bezbradica

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One of the fundamental requirements for overall human well-being is a stable and balanced microbiome. Aside from the microorganisms that reside within the body, a large number of microorganisms, especially bacteria, swarming the human skin is in homeostasis with the host and represents a skin microbiota. Even though the immune system of the skin is capable of distinguishing between commensal and potentially harmful transient bacteria, the cutaneous microbial balance can be disrupted under certain circumstances. In that case, a reduction in the skin microbiota diversity, as well as changes in metabolic activity, results in dermal infections and inflammation. Probiotics and prebiotics have the potential to play a significant role in the treatment of these skin disorders. The most common resident bacteria found on the skin, Staphylococcus epidermidis, can act as a potential skin probiotic, contributing to the protection of healthy skin from pathogen colonization, such as Staphylococcus aureus, which is related to atopic dermatitis exacerbation. However, as it is difficult to meet regulations in cosmetic products, another therapy approach could be topical prebiotic supplementation of the skin microbiota. In recent research, polyphenols are attracting scientists' interest as biomolecules with possible prebiotic effects on the skin microbiota. This research aimed to determine how herbal extracts rich in different polyphenolic compounds (lemon balm, St. John's wort, coltsfoot, pine needle, and yarrow) affected the growth of S. epidermidis and S. aureus. The first part of the study involved screening plants to determine if they could be regarded as probable candidates to be skin prebiotics. The effect of each plant on bacterial growth was examined by supplementing the nutrient medium with their extracts and comparing it with control samples (without extract). The results obtained after 24 h of incubation showed that all tested extracts influenced the growth of the examined bacteria to some extent. Since lemon balm and St. John's wort extracts displayed bactericidal activity against S. epidermidis, whereas coltsfoot inhibited both bacteria equally, they were not explored further. On the other hand, pine needles and yarrow extract led to an increase in S. epidermidis/S. aureus ratio, making them prospective candidates to be used as skin prebiotics. By examining the prebiotic effect of two extracts at different concentrations, it was revealed that, in the case of yarrow, 0.1% of extract dry matter in the fermentation medium was optimal, while for the pine needle extract, a concentration of 0.05% was preferred, since it selectively stimulated S. epidermidis growth and inhibited S. aureus proliferation. Additionally, the total polyphenols and flavonoid content of the two extracts were determined, revealing different concentrations and polyphenol profiles. Since yarrow and pine extracts affected the growth of skin bacteria in a dose-dependent manner, by carefully selecting the quantities of these extracts, and thus polyphenols content, it is possible to achieve desirable alterations of skin microbiota composition, which may be suitable for the treatment of atopic dermatitis.

Keywords: herbal extracts, polyphenols, skin microbiota, skin prebiotics

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Authors: G. Blugan, B. Jiang, J. Thornberry, P. Sturzenegger, U. Gonzenbach, M. Misson, D. Cartlidge, R. Stenerud, J. Kuebler

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Low-cost ceramic spheres were developed and manufactured from the engineering ceramic aluminium oxide. Hollow spheres of 50 mm diameter with a wall thickness of 0.5-1.0 mm were produced via an adapted slip casting technique. It was possible to produce the spheres with good repeatability and with no defects or failures in the spheres due to the manufacturing process. The spheres were developed specifically for use in buoyancy devices for deep-sea exploration conditions at depths of 3000 m below sea level. The spheres with a 1.0 mm wall thickness exhibit a buoyancy of over 54% while the spheres with a 0.5 mm wall thickness exhibit a buoyancy of over 73%. The mechanical performance of the spheres was confirmed by performing a hydraulic burst pressure test on individual spheres. With a safety factor of 3, all spheres with 1.0 mm wall thickness survived a hydraulic pressure of greater than 150 MPa which is equivalent to a depth of more than 5000 m below sea level. The spheres were then incorporated into a buoyancy module. These hollow aluminium oxide ceramic spheres offer an excellent possibility of deep-sea exploration to depths greater than the currently used technology.

Keywords: buoyancy, ceramic spheres, deep-sea, oil exploration

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Authors: Girum Tedla Assefa

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Background: Granulomatous mycosis fungoides is an extremely rare type of cutaneous T-cell lymphoma (<55 cases reported worldwide). Case report: A 36-year-old female presented with soft tissue atrophy of right lower limb (dermis + hypodermis) of 22 years and plaques over trunk of 3 years duration. Histological examination of a biopsy taken from the atrophied tissue showed a granulomatous reaction with epidermotropic atypical lymphocytes. However, in other areas there were only findings of conventional MF without granuloma. Conclusion: The diagnosis of a granulomatous mycosis fungoides depends exclusively on the histological demonstration of granulomas. Distinct clinical characteristics are not present. This case highlights the importance of thorough investigation of lipoatrophic skin changes in the adult to exclude underlying causes, including MF.

Keywords: cutaneous lymphoma, granulomatous skin lymphoma, mycoses fungoides, skin atrophy

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Authors: Junwon Seo, Bipin Adhikari, Euiseok Jeong

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This paper is intended to evaluate the structural performance of welded electronic road signs under various damage scenarios (DSs) using a finite element (FE) model calibrated with full-scale ultimate load testing results. The tested electronic road sign specimen was built with a back skin made of 5052 aluminum and two channels and a frame made of 6061 aluminum, where the back skin was connected to the frame by welding. The size of the tested specimen was 1.52 m long, 1.43 m wide, and 0.28 m deep. An actuator applied vertical loads at the center of the back skin of the specimen, resulting in a displacement of 158.7 mm and an ultimate load of 153.46 kN. Using these testing data, generation and calibration of a FE model of the tested specimen were executed in ABAQUS, indicating that the difference in the ultimate load between the calibrated model simulation and full-scale testing was only 3.32%. Then, six different DSs were simulated where the areas of the welded connection in the calibrated model were diminished for the DSs. It was found that the corners at the back skin-frame joint were prone to connection failure for all the DSs, and failure of the back skin-frame connection occurred remarkably from the distant edges.

Keywords: computational analysis, damage scenarios, electronic road signs, finite element, welded connections

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Authors: Nino Tsamalaidze

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Cold plasma is an ionized neutral gas with a temperature of 30-40 degrees, but the impact of HP includes not only gas, but also active molecules, charged particles, heat and UV radiation of low power The main goal of the technology we describe is to launch the natural function of skin regeneration and improve the metabolism inside, which leads to a huge effect of rejuvenation. In particular: eliminate fine mimic wrinkles; get rid of wrinkles around the mouth (purse-string wrinkles); reduce the overhang of the upper eyelid; eliminate bags under the eyes; provide a lifting effect on the oval of the face; reduce stretch marks; shrink pores; even out the skin, reduce the appearance of acne, scars; remove pigmentation. A clear indication of the major findings of the study is based on the current patients practice. The method is to use combination of cold plasma and liquid threats. The advantage of cold plasma is undoubtedly its efficiency, the result of its implementation can be compared with the result of a surgical facelift, despite the fact that the procedure is non-invasive and the risks are minimized. Another advantage is that the technique can be applied on the most sensitive skin of the face - these are the eyelids and the space around the eyes. Cold plasma is one of the few techniques that eliminates bags under the eyes and overhanging eyelids, while not violating the integrity of the tissues. In addition to rejuvenation and lifting effect, among the benefits of cold plasma is also getting rid of scars, kuperoze, stretch marks and other skin defects, plasma allows to get rid of acne, seborrhea, skin fungus and even heals ulcers. The cold plasma method makes it possible to achieve a result similar to blepharoplasty. Carried out on the skin of the eyelids, the procedure allows non-surgical correction of the eyelid line in 3-4 sessions. One of the undoubted advantages of this method is a short rehabilitation and rapid healing of the skin.

Keywords: wrinkles, telangiectasia, pigmentation, pore closing

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Authors: Isabel Gouveia

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Antimicrobial textile materials may significantly reduce the risk of infections and because they are able to absorb substances from the skin and release therapeutic compounds to the skin, they can also find applications as complementary therapy of skin-diseases as part of standard management. Although functional textiles may be a promising area in skin disease/injury management, as part of standard management, few offer complementary treatment even though they are well known to reduce scratching and aiding emollient absorption, reducing infection, and alleviating pruritus. The reason for this may rely on the low quality of supporting evidence and negative effect that antimicrobial agents may exert on skin microbiome, as for example additional irritation of the vulnerable skin, and by causing resistant bacteria. Several antimicrobial agents have been tested in textiles: quaternary ammonium compounds, silver, polyhexamethylene-biguanides and triclosan have been used, with success. They have powerful bactericidal activity but the majority have a reduce spectrum of microbial inhibition and may cause skin irritation, ecotoxicity and bacteria resistance. Furthermore, the rising flow of strains resistant to last-resort antibiotics rekindles interest in alternative strategies. In this regard, new functional textiles incorporating highly specific antimicrobial agents towards pathogenic bacteria, are required. Recent research has been conducted on naturally occurring antimicrobials as novel alternatives to antibiotics. Conscious of this need our team firstly reported new approaches using L-cysteine and antimicrobial peptides (AMP). Briefly, we were able to develop different immobilization processes towards 6 Log Reduction against bacteria such as S. aureus and K. pneumoniae. Therefore, here we present several innovative antimicrobial textiles incorporating AMP and L-Cysteine which may open new avenues for the medical textiles market and biomaterials in general. Team references will be discussed as an overview and for comparison purposes in terms of potential therapeutic applications.

Keywords: Antimicrobials, Antimicrobial Textiles, Biomedical Textiles, Biomimetic surface functionalization

Procedia PDF Downloads 118

Authors: Viriyavudh Sim, SeungHyun Kim, JungKyu Choi, WooYoung Jung

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Glass Fiber Reinforced Polymer (GFRP) is a major evolution for energy dissipation when used as infill material for seismic retrofitting of steel frame, a basic PMC infill wall system consists of two GFRP laminates surrounding an infill of foam core. This paper presents numerical analysis in terms of buckling resistance of GFRP sandwich infill panels system under the influence of environment temperature and stacking sequence of laminate skin. Mode of failure under in-plane compression is studied by means of numerical analysis with ABAQUS platform. Parameters considered in this study are contact length between infill and frame, laminate stacking sequence of GFRP skin and variation of mechanical properties due to increment of temperature. The analysis is done with four cases of simple stacking sequence over a range of temperature. The result showed that both the effect of temperature and stacking sequence alter the performance of entire panel system. The rises of temperature resulted in the decrements of the panel’s strength. This is due to the polymeric nature of this material. Additionally, the contact length also displays the effect on the performance of infill panel. Furthermore, the laminate stiffness can be modified by orientation of laminate, which can increase the infill panel strength. Hence, optimal performance of the entire panel system can be obtained by comparing different cases of stacking sequence.

Keywords: buckling resistance, GFRP infill panel, stacking sequence, temperature dependent

Procedia PDF Downloads 374

Authors: Md. Imran H. Khan, T. Farrell, M. A. Karim

Abstract:

Highly porous and hygroscopic characteristics of pear make it complex to understand the cellular level water distribution. In pear tissue, water is mainly distributed in three different spaces namely, intercellular water, intracellular water, and cell wall water. Understanding of these three types of water in pear tissue is crucial for predicting actual heat and mass transfer during drying. Therefore, the aim of the present study was to investigate the proportion of intercellular water, intracellular water, and cell wall water inside the pear tissue. During this study, Green Anjou Pear was taken for the investigation. The experiment was performed using 1H-NMR- T2 relaxometry. Various types of water component were calculated by using multi-component fits of the T2 relaxation curves. The experimental result showed that in pear tissue 78-82% water exist in intracellular space; 12-16% water in intercellular space and only 2-4% water exist in the cell wall space. The investigated results quantify different types of water in plant-based food tissue. The highest proportion of water exists in intracellular spaces. It was also investigated that the physical properties of pear and the proportion of the different types of water has a strong relationship. Cell wall water depends on the proportion of solid in the sample tissue whereas free water depends on the porosity of the material.

Keywords: intracellular water, intercellular water, cell wall water, physical property, pear

Procedia PDF Downloads 253

Authors: Emin Z. Mahmud

Abstract:

This paper presents the observations from a series of shaking-table tests done on a 1:1 scaled confined masonry wall model, with opening for a door – specimens CMDuS (confined masonry wall with opening for a door before strengthening) and CMDS (confined masonry wall with opening for a door after strengthening). Frequency and stiffness changes before and after GFRP (Glass Fiber Reinforced Plastic) wall strengthening are analyzed. Definition of dynamic properties of the models was the first step of the experimental testing, which enabled acquiring important information about the achieved stiffness (natural frequencies) of the model. The natural frequency was defined in the Y direction of the model by applying resonant frequency search tests. It is important to mention that both specimens CMDuS and CMDS are subjected to the same effects. The tests are realized in the laboratory of the Institute of Earthquake Engineering and Engineering Seismology (IZIIS), Skopje. The specimens were examined separately on the shaking table, with uniaxial, in-plane excitation. After testing, samples were strengthened with GFRP and re-tested. The initial frequency of the undamaged model CMDuS is 13.55 Hz, while at the end of the testing, the frequency decreased to 6.38 Hz. This emphasizes the reduction of the initial stiffness of the model due to damage, especially in the masonry and tie-beam to tie-column connection. After strengthening of the damaged wall, the natural frequency increases to 10.89 Hz. This highlights the beneficial effect of the strengthening. After completion of dynamic testing at CMDS, the natural frequency is reduced to 6.66 Hz.

Keywords: behaviour of masonry structures, Eurocode, frequency, masonry, shaking table test, strengthening

Procedia PDF Downloads 130

Authors: G. Ravi Kiran, G. Radhakrishnamacharya

Abstract:

This paper investigates the effects of slip boundary condition and wall properties on the dispersion of a solute matter in peristaltic flow of an incompressible micropolar fluid through a porous medium. Long wavelength approximation, Taylor's limiting condition and dynamic boundary conditions at the flexible walls are used to obtain the average effective dispersion coefficient in the presence of combined homogeneous and heterogeneous chemical reactions. The effects of various pertinent parameters on the effective dispersion coefficient are discussed. It is observed that peristalsis enhances dispersion. It also increases with micropolar parameter, cross viscosity coefficient, Darcy number, slip parameter and wall parameters. Further, dispersion decreases with homogenous chemical reaction rate and heterogeneous chemical reaction rate.

Keywords: chemical reaction, dispersion, peristalsis, slip condition, wall properties

Procedia PDF Downloads 466

Authors: Ayat E. Ali, Christeen R. Aziz, Merna A. Helmy, Mohammed M. Malek, Sherif H. El-Gohary

Abstract:

Goal: Purpose of the project was to make a plastic surgery prediction by using pre-operative images for the plastic surgeries’ patients and to show this prediction on a screen to compare between the current case and the appearance after the surgery. Methods: To this aim, we implemented a software which used data from the internet for facial skin diseases, skin burns, pre-and post-images for plastic surgeries then the post- surgical prediction is done by using K-nearest neighbor (KNN). So we designed and fabricated a smart mirror divided into two parts a screen and a reflective mirror so patient's pre- and post-appearance will be showed at the same time. Results: We worked on some skin diseases like vitiligo, skin burns and wrinkles. We classified the three degrees of burns using KNN classifier with accuracy 60%. We also succeeded in segmenting the area of vitiligo. Our future work will include working on more skin diseases, classify them and give a prediction for the look after the surgery. Also we will go deeper into facial deformities and plastic surgeries like nose reshaping and face slim down. Conclusion: Our project will give a prediction relates strongly to the real look after surgery and decrease different diagnoses among doctors. Significance: The mirror may have broad societal appeal as it will make the distance between patient's satisfaction and the medical standards smaller.

Keywords: k-nearest neighbor (knn), face detection, vitiligo, bone deformity

Procedia PDF Downloads 163

Authors: Mohamed El-Sayed Mosaad

Abstract:

An analytic approach is obtained for the steady heat transfer problem of two fluid systems, in thermal communication via heat conduction across a solid wall separating them. The two free convection layers created on wall sides are assumed to be in parallel flow. Fluid-solid interface temperature on wall sides is not prescribed in analysis in advance; rather, determined from conjugate solution among other unknown parameters. The analysis highlights the main conjugation parameters controlling thermal interaction process of involved heat transfer modes. Heat transfer results of engineering importance are obtained.

Keywords: conjugate heat transfer, boundary layer, convection, thermal systems

Procedia PDF Downloads 379

Authors: Belmiloud Mohamed Amine, Sad Chemloul Nord-Eddine

Abstract:

In this study we investigated numerically heat transfer by mixed convection coupled to radiation in a square cavity; the upper horizontal wall is movable. The purpose of this study is to see the influence of the emissivity and the varying of the Richardson number on the variation of the average Nusselt number. The vertical walls of the cavity are differentially heated, the left wall is maintained at a uniform temperature higher than the right wall, and the two horizontal walls are adiabatic. The finite volume method is used for solving the dimensionless governing equations. Emissivity values used in this study are ranged between 0 and 1, the Richardson number in the range 0.1 to10. The Rayleigh number is fixed to Ra = 10000 and the Prandtl number is maintained constant Pr = 0.71. Streamlines, isothermal lines and the average Nusselt number are presented according to the surface emissivity. The results of this study show that the Richardson number and emissivity affect the average Nusselt number.

Keywords: mixed convection, square cavity, wall emissivity, lid-driven, numerical study

Procedia PDF Downloads 346