area and perimeter
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2021 ◽  
Vol 40 (3) ◽  
pp. 115-125
Author(s):  
Leo Theodon ◽  
Tatyana Eremina ◽  
Kassem Dia ◽  
Fabrice Lamadie ◽  
Jean-Charles Pinoli ◽  
...  

This paper presents a new method for estimating the parameters of a stochastic geometric model for multiphase flow image processing using local measures. Local measures differ from global measures in that they are only based on a small part of a binary image and consequently provide different information of certain properties such as area and perimeter. Since local measures have been shown to be helpful in estimating the typical grain elongation ratio of a homogeneous Boolean model, the objective of this study was to use these local measures to statistically infer the parameters of a more complex non-Boolean model from a sample of observations. An optimization algorithm is used to minimize a cost function based on the likelihood of a probability densityof local measurements. The performance of the model is analysed using numerical experiments and real observations. The errors relative to real images of most of the properties of the model-generated images are less than 2%. The covariance and particle size distribution are also calculated and compared.


Foods ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2787
Author(s):  
Marta Igual ◽  
Maria Simona Chiş ◽  
Adriana Păucean ◽  
Dan Cristian Vodnar ◽  
Sevastița Muste ◽  
...  

Serious issues and challenges of the world’s population are represented by dwindling natural food resources and the scale-up of sustainable food manufacturing. Therefore, the valorization of co-products from the food industry represents new methods for food development. The principal goal of the study was to capitalize rose hip (Rosa canina) co-product powder in extrudates, highlighting its influence on extrusion parameters, physicochemical, and nutritional characteristics. The water absorption index, swelling index, and hygroscopicity increased with the rose hip co-product addition. Furthermore, water solubility index, expansion index, porosity, image parameters (area and perimeter) of the extrudates decreased. Lycopene, β-Carotene, Zea-esters, and lutein were the main carotenoids identified in the extrudates; whereas Catechin, Di-gallic acid, Procyanidin dimmer 1, Procyanidin dimmer 2, and Isorhamnetin-glucuronide were the main flavonoids. Strong Pearson correlations were identified between carotenoids, total flavonoids, vitamin C, total folate, and antioxidant activity. Valorization of the Rosa canina powder co-product led to value-added products—corn extrudates—rich in bioactive compounds.


2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Hatem H. Allam ◽  
Alsufiany Muhsen ◽  
Mosfer A. Al-walah ◽  
Abdulmajeed N. Alotaibi ◽  
Shayek S. Alotaibi ◽  
...  

Background. Obesity contributes to the acquired flatfoot deformity which in turn impairs balance. Aim. The purpose of the current study was to compare the effect of plyometric exercises with flatfoot corrective exercises on balance, foot posture, and functional mobility in obese children with a flexible flatfoot. Methods. Forty-seven children participated in the study. Their age ranged from 7 to 11 years. Participants were randomly divided into 3 groups: experimental group I (EGI), experimental group II (EGII), and the control group (CG). The EGI received plyometric exercises and the EGII received corrective exercises, 2 sessions weekly for 10 weeks. The control group did not perform any planned physical activities. The Prokin system was used to assess balance, the timed up and go test (TUG) was used to assess functional mobility, and the navicular drop test (NDT) was used to assess foot posture. Results. EGI showed significant improvement in all balance parameters, foot posture, and TUG. EGII showed improvement in the ellipse area and perimeter in addition to foot posture and TUG. Conclusion. Plyometric exercises and foot correction exercises had a positive effect on foot posture, balance, and functional mobility in obese children with flatfeet.


2021 ◽  
Author(s):  
Jenna Watson

Frontal sinus radiographs are frequently used to identify human remains. However, the method of visually comparing antemortem (AM) to postmortem (PM) cranial radiographs has been criticized for being a subjective approach that relies on practitioner experience, training, and judgment rather than on objective, quantifiable procedures with published error rates. The objective of this study was to explore the use of ArcMap and its spatial analysis tool, Similarity Search, as a quantifiable, reliable, and reproducible method for identifying frontal sinus matches from cranial radiographs. Using cranial radiographs of 100 individuals from the William M. Bass DonatedSkeletal Collection, the frontal sinuses were digitized to create two-dimensional polygons. Similarity Search was evaluated on its ability to identify the correct AM radiograph using three variables: the number of scallops and the area and perimeter values of the polygons. Using all three variables, Similarity Search correctly identified the true match AM polygon in 58% of the male groups and in 62% of the female groups. These results indicate that ArcMap can be used with frontal sinus radiographs. However, further analysis of the three variables revealed that scallop number did not provide sufficient information about frontal sinus shape to increase the accuracy of Similarity Search, and area and perimeter only captured the size of the frontal sinus polygons, not shape. This research is a first step in developing a user-friendly, quantifiable frontal sinus comparison method for the purpose of positive identification.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jie Xu ◽  
Vassili Savinov ◽  
Eric Plum

AbstractOptical nonlinearities of matter are often associated with the response of individual atoms. Here, using a toy oscillator model, we show that in the confined geometry of a two-dimensional dielectric nanoparticle a collective nonlinear response of the atomic array can arise from the Coulomb interactions of the bound optical electrons, even if the individual atoms exhibit no nonlinearity. We determine the multipole contributions to the nonlinear response of nanoparticles and demonstrate that the odd order and even order nonlinear electric dipole moments scale with the area and perimeter of the nanoparticle, respectively.


Author(s):  
Geoffrey B. Saxe ◽  
Amelia M. Farid

AbstractThis article uses a cultural-developmental framework to illuminate the interplay between collective and individual activity in the mathematical reasoning displayed in a university Masters level lesson on fractals. During whole class and small group discussions, eleven students, guided by an instructor, engage in inductive reasoning about the area and perimeter of the Sierpinski triangle, a unique mathematical object with zero area and infinite perimeter. As participants conceptualize and communicate about the Sierpinski problem, they unwittingly generate a linguistic register of action word forms (e.g., fencing, zooming) and object word forms (e.g., area, infinity) to serve Sierpinski-linked mathematical reasoning functions, a register that we document in the first analytic section of the article. In the second analytic section, we report a developmental analysis of microgenetic, ontogenetic, and sociogenetic shifts in the word forms constitutive of the register and their varied functions in participants’ activities. In the third analytic section, we provide a cultural analysis of the classroom’s collective practices, practices that enable and constrain participants’ constructions of form-function relations constituting the register. We examine the ways in which participants work to establish a common ground of talk in their communicative exchanges, exchanges supported by classroom norms for public displays of reasoning and active listening to one another’s ideas. We show that it is as participants work to establish a common ground that the register emerges and is reproduced and altered. We conclude by pointing to ways that the analytic framework can be extended to illuminate learning processes in other classroom settings.


Author(s):  
Т. С. Кривоногова ◽  
О. М. Гергет ◽  
В. А. Желев ◽  
Е. В. Голикова ◽  
Е. В. Михалев ◽  
...  

Перинатальная патология центральной нервной системы занимает ведущие позиции в структуре детской заболеваемости, что диктует необходимость поиска оптимальных подходов к ранней диагностике гипоксически-ишемических и травматических поражений центральной нервной системы, в том числе с использованием технологий математического моделирования. Цель работы состоит в создании и апробации математической модели дифференциальной диагностики гипоксически-ишемических и травматических поражений нервной системы у детей с использованием метода кариометрии. В исследование были включены 290 доношенных детей первого года жизни: первая группа сравнения включала 120 новорожденных с гипоксически-ишемическим поражением центральной нрвной системы, вторая – 120 новорожденных с ее травматическим поражением, контрольная группа включала 50 здоровых детей. Всем детям в возрасте 1, 3, 6, 9 месяцев и 1 года оценивались физическое и нервно-психическое развитие, двигательные функции по методу Л. Т. Журбы. На первом месяце жизни проводились нейросонография головного мозга, рентгенологическое обследование головы и шейного отдела позвоночника в двух проекциях. В возрасте 1, 3 и 6 месяцев выполнялось морфологическое исследование лимфоцитов (кариометрия). Для создания математической модели дифференциальной диагностики гипоксически-ишемических и травматических поражений нервной системы были взяты 12 показателей нейросонографии и 4 показателя морфологии лимфоцитов периферической капиллярной крови (площадь и периметр ядра, площадь и периметр клетки). В построении диагностической модели использовали самообучающуюся искусственную нейронную сеть, работа которой воспроизведена при помощи созданного программного приложения. Исследование показало, что полученная нами модель проста в использовании, экономит время на постановку диагноза, обладает высокой степенью распознавания: специфичность модели – 89,2%, чувствительность 92%. Perinatal pathology of the Central nervous system (CNS) occupies a leading position in the structure of childhood morbidity, which dictates the need to find optimal approaches to the early diagnosis of hypoxic-ischemic and traumatic CNS lesions, including using mathematical modeling technologies. Objective: to create and test a mathematical model for differential diagnosis of hypoxic-ischemic and traumatic lesions of the nervous system in children using the karyometry method. The study included 290 full-term infants of the first year of life: the first comparison group included 120 newborns with hypoxic – ischemic CNS damage, the second group-120 newborns with traumatic CNS damage, the control group included 50 healthy children. All children aged 1, 3, 6, 9 months and 1 year were evaluated for physical and neuropsychic development, motor functions according to the method of L. T. Zhurba. In the first month of life, neurosonography of the brain, x-ray examination of the head and cervical spine in two projections were performed. Morphological examination of lymphocytes (karyometry) was performed at the ages of 1, 3 and 6 months. To create a mathematical model for differential diagnosis of hypoxic-ischemic and traumatic lesions of the nervous system, 12 indicators of neurosonography and 4 indicators of peripheral capillary blood lymphocyte morphology (area and perimeter of the nucleus, area and perimeter of the cell) were taken. A self-learning artificial neural network was used in the construction of the diagnostic model, the operation of which was reproduced using the created software application. The study showed that the model we obtained is easy to use, saves time for diagnosis, and has a high degree of recognition: the model specificity is 89,2%, and the sensitivity is 92%.


Animals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2762
Author(s):  
Ippolito De Amicis ◽  
Jasmine Fusi ◽  
Giuseppe Marruchella ◽  
Maria T. Zedda ◽  
Andrea Mazzatenta ◽  
...  

This study investigated the postpartum (PP) uterine involution in nine multiparous Martina Franca jennies with at term, normal, and singleton foaling. Transrectal ultrasonography performed at Days 1, 3, 7, 14, 21, and 28 showed that the uterine tip diameters did not differ between the post-pregnant (PPH) and non-post-pregnant uterine horns (NPPH), whereas the diameter of the middle PPH was larger than the NPPH until Day 7 (p < 0.05). The diameter of the corpora-cornual junction resulted larger in the PPH than NPPH at Day 7 (p < 0.05). At Day 3, the microcaruncolae were not detected. Endometrial glands (GL) number increased, with the highest value on Day 28. Endometrial GL area and perimeter decreased (p < 0.001) from Day 1 to Day 28. Epithelial thickness increased from Days 1–3 to Day 7 (p < 0.001), and concurrently with the foal heat to Day 14 (p < 0.001), with a decrease at Days 21–28. A marked neutrophils reduction on Day 7 and eosinophil increase from the first three days to Days 7–14 was observed. The results suggest that, in Martina Franca jennies with normal foaling, the PP uterine involution can be considered complete on Day 14.


2021 ◽  
Vol 8 ◽  
Author(s):  
Chun Yan ◽  
Fan Li ◽  
Min Hou ◽  
Xiaoyuan Ye ◽  
Lishi Su ◽  
...  

Purpose: To investigate the involvement of peripapillary zone vascular abnormalities in Behcet's uveitis (BU) and associated visual dysfunction. We evaluated the retinal and choroidal microvascular features in both macular and peripapillary areas of BU patients to identify vascular abnormalities contributing to reduced best-corrected visual acuity (BCVA) using optical coherence tomography angiography (OCTA).Methods: A prospective, observational study was conducted in 24 eyes of 13 patients with BU and 24 eyes of 15 healthy participants as controls. They received a standard eye examination and were recorded by OCTA measurements of macular and peripapillary areas. The vascular densities of superficial capillary plexus (SCP) and deep capillary plexus (DCP), choroidal flow area, radial peripapillary capillary network (RPCN) density, foveal avascular zone (FAZ) area and perimeter, full retinal thickness (FRT), and peripapillary retinal nerve fiber layer thickness (pRNFLT) were measured.Correlations among microvascular, structural, and functional changes were assessed.Results: Our findings uncovered that the vascular density was significantly reduced in the peripapillary zone of BU eyes compared to healthy eyes, especially in the inferior subfield of the RPCN. The vascular densities of SCP and DCP quadrants within the macular zone had no significant difference between BU and control groups except for DCP density of the nasal parafoveal quadrant. Both FAZ area and perimeter were greater but without statistical significance in the BU group. Compared to healthy eyes, the choriocapillaris flow area was smaller while the FRT and pRNFLT were greater in the BU group. Notably, there was a significant correlation between the reduction in RPCN vascular density and decreased BCVA in BU patients.Conclusion: Based on OCTA, vascular changes associated with BU are more prominent in the peripapillary zone than those in the macular zone. The vascular density of the RPCN could serve as a sensitive indicator to monitoring BU pathogenic progression and treatment response using a non-invasively method of OCTA.


2021 ◽  
Vol 12 (3) ◽  
pp. 487-506
Author(s):  
Wanty Widjaja ◽  
Colleen Vale

One pedagogical approach to challenge a persistent misconception is to get students to test a conjecture whereby they are confronted with the misconception. A common misconception about a ‘direct linear relationship’ between area and perimeter is well-documented. In this study, Year 4-6 students were presented with a conjecture that a rectangle with a larger perimeter will always have a larger area. Eighty-two (82) students’ written responses from three elementary schools in Victoria, Australia were analyzed. The findings revealed that Year 4-6 students could find multiple examples to support the conjecture but they struggled to find counterexamples to refute the conjecture. The findings underscored the importance of developing elementary school students’ capacity to construct counterexamples and recognize that it is sufficient to offer one counterexample in refuting a conjecture about all cases. Implications for ­teaching practice to support investigating and testing a conjecture are discussed.


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