Buckling characteristics of sandwich conical shells with variable skin thickness

2021 ◽  
Author(s):  
M. Zarei ◽  
G. H. Rahimi
Keyword(s):  
Skin Thickness ◽  
Conical Shells

The Influence of Variable Shell Thickness On the Vibrational Behavior of Composite Sandwich Conical Shells with Geodesic Lattice Cores

2021 ◽  
pp. 2150168
Author(s):  
M. Zarei ◽  
G. H. Rahimi ◽  
M. Hemmatnezhad
Keyword(s):  
Orientation Angle ◽  
Shear Deformation Theory ◽  
Longitudinal Direction ◽  
Vertex Angle ◽  
Skin Thickness ◽  
Equivalent Stiffness ◽  
Power Series Method ◽  
Conical Shells ◽  
Vibrational Behavior ◽  
Lattice Core

This paper investigates the vibrational behavior of sandwich conical shells with geodesic lattice core and variable skin thicknesses using analytical and numerical approaches. The filament wound conical shell has been considered to have varying skin thickness along the longitudinal direction. The smeared stiffener approach has been used to obtain the equivalent stiffness parameters due to the geodesic lattice core via the force and moment analyses of a unit cell. Superimposing the stiffness contribution of the stiffeners with those due to the inner and outer skins, one can calculate the equivalent stiffness of the whole structure. The equations of motion have been formulated based on the first-order shear deformation theory. The power series method has been implemented for extracting the natural frequencies of vibration. To validate the analytical results, a 3-D finite element model has been provided which is then used to conduct an extensive parametric study. The comparisons indicate an acceptable agreement between the two approaches. Moreover, the effect of variable skin thickness on the natural frequency has been examined. Furthermore, the influences of skin lamination angle, semi-vertex angle of the cone and stiffeners orientation angle have been discussed. The obtained results can be used for future relevant researches.

A Follow-up Study of Skin Thickness in a Patient with Systemic Sclerosis Using an Ultrasound Apparatus.

1996 ◽  
Vol 58 (1) ◽  
pp. 29-31
Author(s):  
Hironobu URA ◽  
Hironobu IHN ◽  
Sakae HARADA ◽  
Tsutomu FURUYA ◽  
Michiro SHIMOZUMA ◽  
...  
Keyword(s):  
Systemic Sclerosis ◽  
Skin Thickness ◽  
Follow Up Study

Free vibration of pretwisted, cantilevered composite shallow conical shells

AIAA Journal ◽  
1997 ◽  
Vol 35 ◽  
pp. 327-333
Author(s):  
C. W. Lim ◽  
S. Kitipornchai ◽  
K. M. Liew
Keyword(s):  
Free Vibration ◽  
Conical Shells

Adaptive changes of the hair coat of the horses of zabaykalsky aborigenous breed

2019 ◽  
Vol 49 (4) ◽  
pp. 101-105 ◽  
Author(s):  
G. M. Shkyratova ◽  
B. Z. Bazaron ◽  
T. N. Khamiruev ◽  
S. M. Dashinimaev
Keyword(s):  
Seasonal Changes ◽  
Climatic Conditions ◽  
Skin Thickness ◽  
Summer Period ◽  
Hair Coat ◽  
Skin Fold ◽  
Winter Grazing ◽  
Shoulder Blade ◽  
Quantitative Indicators

The seasonal changes in the skin thickness and structure of the horses’ coat, as signs of adaptation to environmental factors, were studied. The experiment was carried out with the livestock kept in a herd using winter-grazing technology without additional feedings in the climatic conditions of the Trans-Baikal Territory. The objects of the research were adult mares of Zabaikalsky breed of horses of the same age, class and fatness. The studies were carried out in the middle of each season (May, July, October, February). The length of the coat was measured with a caliper, the coat itself with the determination of the ratio of hair (fl uffy hair, heterotype hair and coarse hair) and the thickness of the skin fold were measured in accordance with the approved methodological recommendations. The minimum skin thickness in winter was detected in mares on the back and shoulder blade – 4.3 and 4.4 mm, the maximum – on the side and thigh – 4.5 4.6 mm. When compared with the summer period, the increase on the side was 0.8 mm, whereas on the back, shoulder blade and thigh – 0.4 mm (p ≤ 0,001). In spring, thickening of the skin was noted within 0.1-0.3 mm in the same topographic areas, compared to autumn. The quantitative indicators of the coat changed depending on the season of the year. In winter, the coat contained more fl uffy hair (23.10%), and less coarse hair (68.24%), in summer there was a lower content of fl uffy hair (4.33%), but more coarse hair (94.01%.) Sharp seasonal changes were noted with regard to the length of the hair. The longest hair was found in winter and spring – 4.96 and 4.26 cm, whereas the shortest – in summer and autumn – 0.94 and 1.90 cm, respectively.

Evaluasi Keragaan Beberapa Hibrida Semangka Koleksi Balai Penelitian Tanaman Buah Tropika

2019 ◽  
Vol 15 (2) ◽  
pp. 101-105
Author(s):  
Makful Makful ◽  
Kuswandi Kuswandi ◽  
Sahlan Sahlan ◽  
Mega Andini
Keyword(s):  
Skin Color ◽  
Sweet Taste ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Hybrid Breeding ◽  
Skin Thickness ◽  
Tropical Fruit ◽  
Total Soluble Solids ◽  
Soluble Solid ◽  
High Yielding Varieties

Hybrid breeding of watermelon has led to the formation of high-yielding varieties. The objectives of the research were to determine the performance of hybrid watermelon of the Indonesian Tropical Fruit Research Institute (ITFRI) collection and to evaluate the superiority of each hybrid. The research has been conducted at Sumani Experimental Garden, ITFRI, Solok, West Sumatera, from April to July 2016. The material used consisted of 19 cross combinations. The data from this descriptive study were presented in the form of averages and pictures. The results showed that the hybrids that were tested showed diversity in size, fruit skin color, flesh color, skin thickness and fruit sweetness. Hybrids with three excellent characters, i.e. medium fruit weight, high total soluble solids (TSS) value, and moderate rind thickness, were not yet obtained. Hybrids that had the superiority in term of sweet taste and shelf life were BT1 × SGP, BT4 × BT4P, BT5 × BT4, BT6 × SGP and SGP × BT6. Keywords: hybrid, performance, total soluble solids, watermelon   ABSTRAK Pemuliaan hibrida pada semangka mengarah kepada pembentukan varietas berdaya hasil tinggi. Penelitian bertujuan untuk mengetahui keragaan hibrida semangka koleksi Balitbu Tropika dan untuk mengevaluasi keunggulan masing-masing hibrida Penelitian dilaksanakan di Kebun Percobaan Sumani, Balitbu Tropika, Solok, Sumatera Barat, dari bulan April sampai dengan Juli 2016. Materi yang digunakan terdiri dari 19 kombinasi persilangan. Data hasil penelitian deskriptif ini ditampilkan dalam bentuk rataan dan gambar. Hasil penelitian menunjukkan bahwa hibrida yang diuji memiliki keragaman dalam ukuran, warna kulit buah, warna daging buah, ketebalan kulit buah dan kemanisan. Belum ditemukan hibrida yang memiliki tiga karakter unggul, yang terdiri dari bobot buah sedang, total padatan terlarut (total soluble solid) tinggi, dan kulit buah agak tebal. Hibrida yang memiliki keunggulan berupa rasa manis dan tahan simpan adalah BT1 × SGP, BT4 × BT4P, BT5 × BT4, BT6 × SGP dan SGP × BT6. Kata kunci: hibrida, keragaan, semangka, total padatan terlarut

EFFICIENT METHOD OF CALCULATING LAYERED CONICAL SHELLS WITH LAGRANGE MULTIGRID ELEMENTS USE

2018 ◽  
Vol 19 (3) ◽  
pp. 423-431
Author(s):  
G. I. Rastorguev ◽  
◽  
A. N. Grishanov ◽  
А. D. Matveev ◽  
◽  
...  
Keyword(s):  
Efficient Method ◽  
Conical Shells

Immunomodulatory Effect of Andrographis paniculata during Lead Induced Toxicity in Broilers

2016 ◽  
Vol 12 (2) ◽  
Author(s):  
R. S. Ingole ◽  
A. S. Chandewar ◽  
M. V. Joshi ◽  
Madhuri Hedau ◽  
S W Hajare ◽  
...  
Keyword(s):  
Lead Acetate ◽  
Lead Toxicity ◽  
Andrographis Paniculata ◽  
Immunomodulatory Effect ◽  
Bursa Of Fabricius ◽  
Control Group ◽  
Skin Thickness ◽  
Broiler Chicks ◽  
Commercial Diet ◽  
Ameliorative Effect

The effect of dietary lead exposure on immunomodulation of broilers and possible ameliorative effect of Andrographis paniculata were studied. One hundred broiler chicks were randomly divided into five equal groups of 20 each. Group T0 served as control while group T1, T2, T3 and T4 birds were provided commercial diet with lead acetate at the dose of 300 ppm in feed. Powder of dry leaves of Andrographis paniculata was mixed in the feed of group T2, T3 and T4 chicks at the dose of 2 gm, 3 gm and 4 gm/kg of feed respectively and fed for 4 weeks. Significant decrease in HI titres in T1 group and significant increase in T4 group suggested increased haemagglutination titre (HI) response. The maximum skin thickness and diameter on 24th and 48th hours was observed in control group birds (T0) and was comparable with T4 group. Microscopically spleen, thymus and bursa of fabricius revealed increase in lymphoid population in birds fed lead acetate along with Andrographis paniculata compared to T1 group. We concluded that Andrographis paniculata has immunomodulatory effect during lead toxicity in broilers.

scholarly journals P151 Self-assessment of scleroderma skin thickness: development and evaluation of the PASTUL questionnaire

Rheumatology ◽  
2021 ◽  
Vol 60 (Supplement_1) ◽  
Author(s):  
Julia Spierings ◽  
Voon H Ong ◽  
Christopher P Denton
Keyword(s):  
Correlation Coefficient ◽  
Upper Limb ◽  
Content Validity ◽  
Health Assessment ◽  
Skin Thickness ◽  
Self Assessment ◽  
Skin Score ◽  
Modified Rodnan Skin Score ◽  
Physical Limitations ◽  
Test Retest Reliability

Abstract Background/Aims  Evaluation of skin is central to both clinical practice and trials in systemic sclerosis (SSc). This is generally done with the modified Rodnan Skin Score (mRSS). Remote consultations are now widely implemented in response to the COVID-19 pandemic, which has inevitably limited evaluation of skin. To monitor skin during this pandemic and to further explore ways to assess skin, we developed the PASTUL (Patient self-Assessment of Skin Thickness in Upper Limb) questionnaire. The aim of this study was to evaluate feasibility and validity of the PASTUL in SSc. Methods  The PASTUL questionnaire specifies a simple grading of skin as normal, mild, moderate, or severely thickened at eight sites of upper limb corresponding to mRSS. Assessed grades were converted to an integer scale [0, 1, 2, 3]. Detailed instructions for patients were provided. Scleroderma Skin PRO (SSPRO) and Scleroderma Health Assessment Disability Index (SHAQ-DI) were also completed. The mRSS was done in a selection of patients. Construct validity was evaluated by examining the correlation between PASTUL, mRSS, SSPRO and SHAQ-DI using Pearson’s correlation coefficient. Content validity was evaluated by scoring relevance, clarity and practical difficulty. Test-retest reliability was estimated using intraclass correlation coefficient (ICC). Results  In total, 107 patients were invited of which 83 (77.6%) completed the questionnaires. The mRSS was undertaken in 61 patients. The PASTUL was completed by patients (83.1%) or by a partner/friend (16.9%). Mean PASTUL score was 11 (SD 6), mean HAQ-DI 1.47 (SD 0.76) and mean SSPRO 49.8 (SD 26.6). PASTUL and SSPRO physical limitations correlated strongly (0.62, p < 0.001). Correlations between PASTUL and total SSPRO and mRSS upper limbs were moderate to weak (0.59, 0.50 and 0.32 respectively). Correlation between PASTUL and mRSS was stronger in lcSSc compared to dcSSc patients (0.61 vs 0.29) and when assessed by a partner/friend compared to patients themselves (0.98 vs 0.45). The PASTUL demonstrated excellent test-retest reliability (ICC of 0.92) and good content validity. P151 Table 1:Correlation of PASTUL score with other outcome measuresOutcome measurePearson's correlation coefficientP-valuemRSS0.48<0.001mRSS upper limbs0.50<0.001SHAQ-DI0.320.004VAS pain0.180.107VAS GI0.130.239VAS breathing0.130.236VAS RP0.090.406VAS DU0.090.466VAS limitations0.250.026SSPRO0.59<0.001SSPRO subdomain PE0.56<0.001SSPRO subdomain PL0.62<0.001SSPRO subdomain EE0.49<0.001SSPRO subdomain SE0.370.001DU, digital ulcers; EE, emotional effects; GI, gastrointestinal; HAQ-DI, Health Assessment Questionnaire Disability Index; mRSS, modified Rodnan skin score; PE, physical effects; PL, physical limitations; RP, Raynaud's phenomenon; SE, social effects Conclusion  Moderate and significant correlations of PASTUL scores with total SSPRO, physical limitation scores and mRSS support the usefulness of PASTUL as an outcome measure and indicates it’s potential for use in virtual clinical settings Disclosure  J. Spierings: None. V.H. Ong: None. C.P. Denton: None.

Formation of α clusters in dilute neutron-rich matter

Science ◽  
2021 ◽  
Vol 371 (6526) ◽  
pp. 260-264 ◽  
Author(s):  
Junki Tanaka ◽  
Zaihong Yang ◽  
Stefan Typel ◽  
Satoshi Adachi ◽  
Shiwei Bai ◽  
...  
Keyword(s):  
Cross Sections ◽  
Cluster Formation ◽  
Reaction Cross ◽  
Skin Thickness ◽  
Neutron Skin ◽  
Heavy Nuclei ◽  
Α Decay ◽  
Neutron Skin Thickness ◽  
Reaction Cross Sections ◽  
Α Particles

The surface of neutron-rich heavy nuclei, with a neutron skin created by excess neutrons, provides an important terrestrial model system to study dilute neutron-rich matter. By using quasi-free α cluster–knockout reactions, we obtained direct experimental evidence for the formation of α clusters at the surface of neutron-rich tin isotopes. The observed monotonous decrease of the reaction cross sections with increasing mass number, in excellent agreement with the theoretical prediction, implies a tight interplay between α-cluster formation and the neutron skin. This result, in turn, calls for a revision of the correlation between the neutron-skin thickness and the density dependence of the symmetry energy, which is essential for understanding neutron stars. Our result also provides a natural explanation for the origin of α particles in α decay.

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