Brownian motions on shape and size-and-shape spaces

1994 ◽  
Vol 31 (1) ◽  
pp. 101-113 ◽  
Author(s):  
Huiling Le
Keyword(s):  
Dual Problem ◽  
Heat Kernels ◽  
Brownian Motions ◽  
Shape Spaces ◽  
Size And Shape ◽  
Shape And Size

The diffusions on the shape and size-and-shape spaces induced by brownian motions on the pre-size-and-shape spaces have been investigated in several papers (cf.). We here address the dual problem: the character of the diffusions on the pre-shape and pre-size-and-shape spaces which induce brownian motions on the shape and size-and-shape spaces. In particular we show that the shape and size-and-shape spaces for k labelled points in ℝm are stochastically complete if k > m and obtain the heat kernels of certain diffusions which induce brownian motions on the size-and-shape spaces.

Brownian motions on shape and size-and-shape spaces

1994 ◽  
Vol 31 (01) ◽  
pp. 101-113 ◽  
Author(s):  
Huiling Le
Keyword(s):  
Dual Problem ◽  
Heat Kernels ◽  
Brownian Motions ◽  
Shape Spaces ◽  
Size And Shape ◽  
Shape And Size

The diffusions on the shape and size-and-shape spaces induced by brownian motions on the pre-size-and-shape spaces have been investigated in several papers (cf.). We here address the dual problem: the character of the diffusions on the pre-shape and pre-size-and-shape spaces which induce brownian motions on the shape and size-and-shape spaces. In particular we show that the shape and size-and-shape spaces for k labelled points in ℝ m are stochastically complete if k > m and obtain the heat kernels of certain diffusions which induce brownian motions on the size-and-shape spaces.

Cooling Rates of Brake Drums and Discs

1965 ◽  
Vol 180 (1) ◽  
pp. 191-205 ◽  
Author(s):  
T.P. Newcomb ◽  
N. Millner
Keyword(s):  
Cooling Rate ◽  
Air Flow ◽  
Vehicle Speed ◽  
Uniform Temperature ◽  
Cooling Rates ◽  
Size And Shape ◽  
Slip Ring ◽  
Disc Brakes ◽  
Shape And Size ◽  
Time Plot

An investigation has been made of the rates of cooling of vehicle brake drums and discs. Thermocouples were inserted in the drums and discs and in the wheel hubs and their outputs fed via slip ring units to meters mounted inside the vehicle. The drums or discs were heated to a uniform temperature of 300°-400°C by drag braking and the rate at which they cooled measured while the vehicle was driven at constant speed. Measurements were made at various speeds in the range 0 to 90 mile/h. From the log (temperature) against time plot a cooling coefficient bv was determined. It is shown that at a vehicle speed v the quantity bv can be expressed in the form bv = b0 +Kv0·8 where b0 represents the loss of heat to the hub and K is a constant depending on the size and shape of the drum or disc. Values of these constants have been determined on a variety of cars having discs and drums varying from 7 in to 11 in diameter and on a lorry fitted with 16·75 in diameter drums. Cooling rates are shown to depend on shape and size of the disc or drum. Results show that the cooling rates of front brakes are about 20 per cent higher than the rear brakes and that front discs cool about 25 per cent more quickly than the corresponding drum size recommended for the same vehicle. The cooling rate of front discs did not change when wire wheels were fitted instead of solid wheels. Ventilated discs and solid discs were also compared. The effect of fitting dust shields on disc brakes is shown to reduce the cooling rates by about 30 per cent. The effect of otherwise disturbing the air flow was studied.

Synthesis and characterization of size- and shape-controlled silver nanoparticles

2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Suparna Mukherji ◽  
Sharda Bharti ◽  
Gauri Shukla ◽  
Soumyo Mukherji
Keyword(s):  
Silver Nanoparticles ◽  
Nucleation And Growth ◽  
Detailed Review ◽  
Size And Shape ◽  
Physical Chemical ◽  
Application Potential ◽  
Shape Controlled ◽  
Synthesis Routes ◽  
Shape And Size

Abstract Silver nanoparticles (AgNPs) have application potential in diverse areas ranging from wound healing to catalysis and sensing. The possibility for optimizing the physical, chemical and optical properties for an application by tailoring the shape and size of silver nanoparticles has motived much research on methods for synthesis of size- and shape-controlled AgNPs. The shape and size of AgNPs are reported to vary depending on choice of the Ag precursor salt, reducing agent, stabilizing agent and on the synthesis technique used. This chapter provides a detailed review on various synthesis approaches that may be used for synthesis of AgNPs of desired size and shape. Silver nanoparticles may be synthesized using diverse routes, including, physical, chemical, photochemical, biological and microwave -based techniques. Synthesis of AgNPs of diverse shapes, such as, nanospheres, nanorods, nanobars, nanoprisms, decahedral nanoparticles and triangular bipyramids is also discussed for chemical-, photochemical- and microwave-based synthesis routes. The choice of chemicals used for reduction and stabilization of nanoparticles is found to influence their shape and size significantly. A discussion on the mechanism of synthesis of AgNPs through nucleation and growth processes is discussed for AgNPs of varying shape and sizes so as to provide an insight on the various synthesis routes. Techniques, such as, electron microscopy, spectroscopy, and crystallography that can be used for characterizing the AgNPs formed in terms of their shape, sizes, crystal structure and chemical composition are also discussed in this chapter. Graphical Abstract:

scholarly journals Sexual size and shape dimorphism in Brachydesmus troglobius Daday, 1889 (Diplopoda, Polydesmida)

ZooKeys ◽  
2020 ◽  
Vol 930 ◽  
pp. 75-88
Author(s):  
Vukica Vujić ◽  
Luka Lučić ◽  
Sofija Pavković-Lučić ◽  
Bojan Ilić ◽  
Zvezdana Jovanović ◽  
...  
Keyword(s):  
Geometric Morphometrics ◽  
Morphological Trait ◽  
Trait Variation ◽  
Size Dimorphism ◽  
Size And Shape ◽  
Shape And Size

Until now, morphological trait variation has been investigated in several millipede species using geometric morphometrics. The present study is the first attempt to explore sexual shape and size dimorphism (SShD and SSD) of morphological structures in Polydesmida. We here analyse antennal, head, and leg SShD and SSD in Brachydesmus troglobius Daday, 1889. Our results show that SSD exists in all of the analysed structures, while SShD is present only in the legs. In comparison with females, males possess longer and wider legs, as well as longer antennae and a shorter head. Contrary to previous findings in some Julida, in B. troglobiusSSD of the antennae and legs varies more than SShD in these morphological structures.

scholarly journals Ukuran dan bentuk lengkung gigi rahang bawah pada orang Papua

e-GIGI ◽  
2016 ◽  
Vol 4 (2) ◽  
Author(s):  
Yoddy G. Saputra ◽  
P. S. Anindita ◽  
Damajanty H.C. Pangemanan
Keyword(s):  
Dental Arch ◽  
Cross Sectional ◽  
Orang Asli ◽  
Purposive Sampling ◽  
Size And Shape ◽  
Key Factor ◽  
Average Size ◽  
Transversal Width ◽  
The Right ◽  
Shape And Size

Abstract: Mandibular size and shape are important information especially in terms to figure out the right diagnosis and the type of treatment a patient should have. Human mandible is a key factor for occlusion adjustment, meanwhile maxilla is following the mandible’s position. Several studies show that the stability of mandibular shape and size determines the success of one’s treatment. Each ethnic group has a particular skeletal pattern as well as shape and size of mandible. This study was aimed to obtain the average size and shape of mandibles among local Papuans. This was a descriptive observational study with a cross-sectional design. Samples were obtained by using purposive sampling method. There were 35 local Papuans aged 18-25 years as subjects. Data were obtained by molding the subject’s mandible, therefore, each subject produced a study model. The study model was measured in sagittal (length) and transversal (width) views based on Raberin method. The results showed that the average lengths of local Papuans’ mandibular size in sagittal view (L31, L61, and L71 in a row) were 6.143; 26.463; and 43.743 mm meanwhile the average widths of local Papuans’ mandibular size (L33, L66, and L77 in a row) were 30.857; 50.971; and 60.971 mm. The mandibular shape of most local Papuans was mid shape (45.8%) meanwhile the least shape of them was pointed (5.7%)Keywords: dental arch size, dental arch shape, mandibular, local Papuan Abstrak: Ukuran dan bentuk lengkung gigi rahang bawah sangat diperlukan dalam menentukan diagnosis dan rencana perawatan yang tepat dalam bidang ortodontik karena rahang bawah merupakan faktor stabilitas oklusi, sedangkan rahang atas menyesuaikan pada rahang bawah. Beberapa peneliti menyatakan bahwa kestabilan bentuk dan ukuran lengkung gigi rahang bawah merupakan faktor stabilitas dari hasil perawatan. Setiap kelompok etnik cenderung memiliki pola skeletal dan ukuran lengkung gigi rahang bawah yang berbeda. Penelitian ini bertujuan untuk mengetahui rerata ukuran dan bentuk lengkung gigi rahang bawah pada orang Papua. Jenis penelitian yaitu deskriptif observasional dengan desain potong lintang. Subjek penelitian ini sebanyak 35 orang Papua berusia 18-25 tahun diperoleh dengan menggunakan teknik purposive sampling. Pengambilan data dalam penelitian dilakukan dengan mencetak rahang bawah setiap subjek penelitian dan didapatkan hasil cetakan berupa model studi. Model studi yang diperoleh diukur dalam arah sagital (panjang) dan transversal (lebar) berdasarkan metode Raberin. Hasil pengukurun diperoleh rerata panjang lengkung gigi rahang bawah pada orang Papua dalam arah sagital (yaitu L31, L61, L71) berturut-turut 6,143; 26,463; dan 43,743 mm, sedangkan rerata lebar lengkung gigi dalam arah transversal (yaitu L33, L66, L77) berturut-turut 30,857; 50,971; dan 60,971 mm. Bentuk lengkung gigi rahang bawah pada orang asli Papua paling banyak yaitu bentuk mid (45,8%) dan yang paling sedikit berbentuk pointed (5,7%). Kata kunci: ukuran lengkung gigi, bentuk lengkung gigi, rahang bawah, orang asli Papua

Two new genera of long clawed Isohypsibioidea Guil, Jørgensen & Kristensen, 2019

Zootaxa ◽  
2020 ◽  
Vol 4729 (2) ◽  
pp. 293-299 ◽  
Author(s):  
ŁUKASZ KACZMAREK ◽  
TOMASZ BARTYLAK ◽  
MILENA ROSZKOWSKA
Keyword(s):  
Genetic Data ◽  
Lateral View ◽  
New Genera ◽  
Size And Shape ◽  
Pharyngeal Apparatus ◽  
Shape And Size

Two new eutardigrade genera Vladimirobius gen. nov. and Weglarskobius gen. nov. are erected for the species Grevenius irregibilis (Biserov, 1992) and Isohypsibius altai Kaczmarek & Michalczyk, 2006a, respectively. They are characterized by strongly modified claws, bucco-pharyngeal apparatus of the Isohypsibius variant, pharyngeal apophyses, and placoids present. The primary branches of internal claws of Vladimirobius gen. nov. are wide in lateral view and have very prominent gibbosity-like projections, whereas primary branches of external claws are thin and extremely long. In Weglarskobius gen. nov. claws IV are similar in shape and size, but the primary branches are extremely long, and thin. Moreover, claws on legs I–III vary greatly in size and shape in Weglarskobius gen. nov. Such supposed autapomorphies fully justify erection of the two new genera, even if the genetic data are presently unavailable. 

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