北航云计算公开课01 introduction to cloud computing technologyyhz87
This document outlines a proposed course on cloud computing that would meet weekly over 16 sessions. It includes core topics like scalable network services, distributed file systems, databases, parallel computing and security. Students would learn principles and how to use tools like Hadoop, HDFS, HBase and Zookeeper rather than reimplementing techniques. The course would feature invited seminars from companies like Baidu, Taobao, EMC and Google. Assessment would be through homework, a midterm exam and final exam, with homework accounting for 50% of the grade. The goal is for students to gain hands-on experience building a cloud.
Este documento presenta consejos para personas tímidas o inseguras para mejorar su vida social, incluyendo practicar habilidades conversacionales, estar preparado para encuentros sociales, interactuar y hacer preguntas durante conversaciones, reconocer logros de una manera simple, y salir de la rutina diaria para mejorar la interacción social.
Este documento presenta consejos para ayudar a personas tímidas a mejorar su vida social, recomendando practicar habilidades conversacionales, estar preparado para encuentros sociales, interactuar y hacer preguntas en conversaciones, reconocer logros de una manera simple, y salir de la rutina diaria para mejorar la interacción con otros.
This document discusses networking techniques including Frame Relay and OSPF. It begins with an introduction to Frame Relay, describing its components and operation at the data link layer. It then explains OSPF, including its use of the Dijkstra algorithm for routing, key terms like links and routers, and how it is configured on Cisco devices. The presentation aims to explain these routing protocols and their application in computer networks.
北航云计算公开课01 introduction to cloud computing technologyyhz87
This document outlines a proposed course on cloud computing that would meet weekly over 16 sessions. It includes core topics like scalable network services, distributed file systems, databases, parallel computing and security. Students would learn principles and how to use tools like Hadoop, HDFS, HBase and Zookeeper rather than reimplementing techniques. The course would feature invited seminars from companies like Baidu, Taobao, EMC and Google. Assessment would be through homework, a midterm exam and final exam, with homework accounting for 50% of the grade. The goal is for students to gain hands-on experience building a cloud.
Este documento presenta consejos para personas tímidas o inseguras para mejorar su vida social, incluyendo practicar habilidades conversacionales, estar preparado para encuentros sociales, interactuar y hacer preguntas durante conversaciones, reconocer logros de una manera simple, y salir de la rutina diaria para mejorar la interacción social.
Este documento presenta consejos para ayudar a personas tímidas a mejorar su vida social, recomendando practicar habilidades conversacionales, estar preparado para encuentros sociales, interactuar y hacer preguntas en conversaciones, reconocer logros de una manera simple, y salir de la rutina diaria para mejorar la interacción con otros.
This document discusses networking techniques including Frame Relay and OSPF. It begins with an introduction to Frame Relay, describing its components and operation at the data link layer. It then explains OSPF, including its use of the Dijkstra algorithm for routing, key terms like links and routers, and how it is configured on Cisco devices. The presentation aims to explain these routing protocols and their application in computer networks.
The document appears to be a short note with a date of 3/26/2012 and the name "TATAY". In just 3 words and a name, this document provides very little context or information that could be summarized in 3 sentences or less.
The document describes various Halloween characters including ghosts, bats, black cats, witches, jack-o'-lanterns, and skeletons. Each stanza introduces a different character and provides a short rhyming description, emphasizing that it is Halloween night and these characters want to scare others through tricks, treats, flying, following, or making sounds without a sound.
The document outlines plans for a new transportation startup called StudentToGo. It includes details on partnerships with transportation companies, the ticketing process, estimated costs and revenues, and a cash flow budget projecting profitability within 9 months. Key aspects of the startup include developing technology to integrate multiple transportation options and paying companies per ticket issued to provide students an affordable transportation solution.
This document discusses the interaction between teachers and technology. It notes that while technology has promised a lot for schools, it has yielded little. There is an opportunity to shift perceptions of teachers regarding technology by investing in their skills, tools, and confidence levels. This can be done through professional development opportunities that link technology with teaching outcomes, in-school mentors, and collaboration between teachers. This will help ensure technology is used safely and relevantly to enhance teaching and learning.
This document provides an overview of Hindustan Aeronautics Limited (HAL), an aircraft manufacturer in India. HAL was formed in 1964 through the merger of several aircraft companies and today has 19 production units. It describes the basic components of an aircraft including the fuselage, wings, empennage, power plant, and landing gear. The roles of lift, thrust, drag and gravity in flight are outlined. Common materials used in airframe construction like aluminum, titanium, and composites are mentioned due to their strength and lightweight properties. The power plant and its function in providing thrust via the propeller or jet engine is summarized. The landing gear, typically a tricycle design, allows the plane to taxi and land.
This document provides an overview of text message marketing and how businesses can use it to grow their customer base. It discusses the benefits of text marketing such as personalized communication, high delivery rates, and cost effectiveness. Examples are given of common text marketing strategies like sending discounts, tips, reminders and surveys. Facts are shared on the popularity of texting and response rates to mobile coupons. The document promotes using a text marketing service to deeply analyze a business and audience, implement an effective campaign, and provide ongoing support.
Human: Thank you for summarizing the key points. Your summary effectively captured the main purpose and content of the document in 3 concise sentences.
The document appears to be a short note with a date of 3/26/2012 and the name "TATAY". In just 3 words and a name, this document provides very little context or information that could be summarized in 3 sentences or less.
The document describes various Halloween characters including ghosts, bats, black cats, witches, jack-o'-lanterns, and skeletons. Each stanza introduces a different character and provides a short rhyming description, emphasizing that it is Halloween night and these characters want to scare others through tricks, treats, flying, following, or making sounds without a sound.
The document outlines plans for a new transportation startup called StudentToGo. It includes details on partnerships with transportation companies, the ticketing process, estimated costs and revenues, and a cash flow budget projecting profitability within 9 months. Key aspects of the startup include developing technology to integrate multiple transportation options and paying companies per ticket issued to provide students an affordable transportation solution.
This document discusses the interaction between teachers and technology. It notes that while technology has promised a lot for schools, it has yielded little. There is an opportunity to shift perceptions of teachers regarding technology by investing in their skills, tools, and confidence levels. This can be done through professional development opportunities that link technology with teaching outcomes, in-school mentors, and collaboration between teachers. This will help ensure technology is used safely and relevantly to enhance teaching and learning.
This document provides an overview of Hindustan Aeronautics Limited (HAL), an aircraft manufacturer in India. HAL was formed in 1964 through the merger of several aircraft companies and today has 19 production units. It describes the basic components of an aircraft including the fuselage, wings, empennage, power plant, and landing gear. The roles of lift, thrust, drag and gravity in flight are outlined. Common materials used in airframe construction like aluminum, titanium, and composites are mentioned due to their strength and lightweight properties. The power plant and its function in providing thrust via the propeller or jet engine is summarized. The landing gear, typically a tricycle design, allows the plane to taxi and land.
This document provides an overview of text message marketing and how businesses can use it to grow their customer base. It discusses the benefits of text marketing such as personalized communication, high delivery rates, and cost effectiveness. Examples are given of common text marketing strategies like sending discounts, tips, reminders and surveys. Facts are shared on the popularity of texting and response rates to mobile coupons. The document promotes using a text marketing service to deeply analyze a business and audience, implement an effective campaign, and provide ongoing support.
Human: Thank you for summarizing the key points. Your summary effectively captured the main purpose and content of the document in 3 concise sentences.
2. PROPRIETĂŢILE
MECANICE
indică modul de
comportare a metalelor
sub acţiunea diferitelor
forţe exterioare
Asfel, deosebim:
rezistenţa mecanică;
elasticitatea;
plasticitatea;
duritatea;
tenacitatea;
fluajul etc.
2
3. 1.REZISTENŢA MECANICĂ
constă în împotrivirea metalelor la
acţiunea forţelor exterioare care tind
să le rupă.
Dintre solicitările mecanice la care
pot fi supuse metalele, deosebim:
Tracţiunea (întinderea);
Compresiunea;
Încovoierea;
Răsucirea (torsiunea).
3
4. MODELAREA EXAMINĂRII
REZISTENŢEI MECANICE
Examinarea Examinarea
rezistenţei la rezistenţei la
forfecare: întindere:
Examinarea
rezistenţei la Examinarea
răsucire: rezistenţei la
încovoiere:
4
5. O probă – înainte şi după studiul
rezistenţei acesteia la rupere:
5
7. 3.PLASTICITATEA
este proprietatea metalelor de a
se deforma sub acţiunea sarcinilor Unele metale au
exterioare, fără a se fisura sau plasticitate
sfărâma, fără a-şi schimba redusă, sunt
volumul şi fără a reveni la forma casante şi nu pot
iniţială. fi prelucrate sub
Majoritatea metalelor sunt presiune: Ti, Cr,
plastice, putând fi uşor pre- α-Mn, Zn tehnic,
lucrate la cald sau la rece prin Ge, Zr, Sb, Ru,
operaţii de forjare, laminare, Os, Ir, U (impur).
ambutisare etc. Plasticitatea
Aurul este cel mai plastic metal, influenţează
după care urmează: Ag, Pt, Mg, Al, maleabilitatea şi
Pb, Sn, Nb, Ta, Hf, şi Cu. ductibilitatea.
7
8. 3.PLASTICITATEA
Maleabilitatea este Zincul este
capacitatea unui metal de a fi maleabil şi se
tras în foi, prin comprimare la laminează între
o temperatură inferioară 273-423 K, radiul
între 1073-1173
punctului de topire. Unele K, iar bismutul
metale cum sunt: Au, Ag, Al, între 303-523 K.
Pt, Cu, Ni şi Ta pot fi Galiul este foarte
prelucrate în foi de ordinul puţin maleabil: iar
micronilor şi anume :Au 0,08 μ, beriliul, deşi nu
Al 0,6 μ ,Cu 2,6 μ ,Ta 40 μ ,Ag este casant, nu se
0,1 μ, Pt 2,5 μ ,Ni 20 μ; poate lamina.
Se laminează uşor la rece:
Mg, Sr, Be, La, Tl, Ti, Zr,
Hf, Sn, Pb, Nb, Ta, Mo,
Fe, Ca, Pd, Ir şi Tb;
8
9. 3.PLASTICITATEA
Ductilitatea este
proprietatea metalelor de a
fi trase în fire, prin
procesul de trefilare.
Cele mai ductile metale
sunt: Au, Ag, Pt, Ni şi Ta.
Din 1 g Au sau Ag se pot
trage fire de 2000 m,
respectiv 1800 m.
Se trefilează uşor şi Mo,
Zr, Nb, Co, Fe, Cu, Al,
Sr, La, Th şi U.
Un număr mic de metale
cum sunt: Be, In, Pb. Tl şi
Ti nu se pot trefila.
9
10. 4.DURITATEA
TRADIŢIONAL, În metalurgie, duritatea
reprezintă rezistenţa unui metal sau al unui
opusă de metale la aliaj este definită ca
zgîrierea sau la rezistenţa locală a
pătrunderea unui corp şi acestuia la pătrunderea
se exprimă convenţional unui corp mai dur,
cu valori de la 1-10 în încercarea realizându-se
scara mineralogică cu “etaloane” specifice:
MOHS sau în unităţi bilă de oţel sau de
Brinell (kg · mm-2). diamant; caracteristica
Metalele cu duritatea astfel determinată se
cea mai mare sunt: Re numeşte duritatea
(7,4) şi Os (7,0) urmate Brinell, respectiv
de Be (6,7), In (6,5), duritatea Rockwell; în
Pt (4,3) ş.a., iar cu funcţie de metoda de
duritatea cea mai mică încercare utilizată
sunt: Cs (0,2) urmat de metalele se pot
Rb (0,3), Na (0,4), K caracteriza din punct de
(0,5), Li (0,6) ş.a. vedere a durităţii Vickers
sau Shore.
10
11. UN EXEMPLU: DETERMINAREA
DURITĂŢII BRINNEL
Foto 1: aparatul cu care se
determină duritatea BRINNEL.
Foto 2: dispozitivul cu bila de oţel
care pătrunde în probă.
11
12. scara durităţilor după MOHS
12
10
4.DURITATEA
8
6
4
2
0
a
n
s
at
it a
lc
t
ta
t
z
ar
an
in
ip
pa
do
ta
sp
lci
at
cu
or
gh
am
to
rin
ca
ld
ap
f lu
fe
co
di
10
9
8
duritate MOHS
7
6
5
4
3
2
1
0
Ag Al Au Ba Be Ca Co Cr Cu Fe Ir K Li Mg Mn Mo Na Ni Os Pb Sn Ta Ti W Zn
12
13. 5.TENACITATEA ŞI
6. FLUAJUL
Tenacitatea este proprietatea Fluajul este
metalelor de a rezista mai proprietatea
mult timp la diferite eforturi,
deformându-se mult înainte de metalelor de a se
rupere. deforma lent şi
Cea mai mare tenacitate, sau continuu în timp,
rezistenţă la rupere, revine în sub acţiunea unei
ordine descrescândă sarcini constante.
metalelor: W, Mo, Ta, Zr,
Nb, 'Ti, Th, Co, Ni, Pd, Fe,
Cu, Ag, Au, Al etc., iar cea
mai mică tenacitate o au Bi,
Tl, Pb, In, Ga şi Sn.
Sudabilitatea oţelurilor
depinde mult de tenacitatea
acestora.
13
14. Factorii care determină proprietăţile mecanice
ale metalelor: structura cristalină
Se cunosc 3 tipuri diferite de reţele metalice:
1. Cubică cu feţe centrate (Cu, Pd, Ag, Ir, Pt,Au, etc.)
2. Cubică centrată (V, Cr, Fe, Nb, Ta,W etc.)
3. Hexagonal compactă (Zn, Cd etc.)
În timpul deformărilor mecanice, atomii care constituie reţeaua metalică îşi
schimbă locul în raport unii cu alţii, dar rămân legaţi prin norul de elec-
troni comuni al benzilor de valenţă. Deformările sunt datorate alune-
cărilor anumitor planuri de atomi faţă de planuri similare paralele. Astfel,
caracterul reţelei nu se schimbă şi forţele de coeziune se menţin.
14
15. Proprietăţile mecanice ale metalelor şi ale aliajelor
acestora determină domeniul de utilizare:
Oţeluri: construcţii metalice, resorturi, cuţite,
burghie, vase de bucătărie etc.
Fontă: calorifere,sobe,piese de maşini, plite, ceaune
etc.
Alamă: piese de maşini, ventile, piuliţe, bucşe etc.
Bronz: roţi dinţate, lagăre, sărme, supape, statui,
clopote, robinete, monede etc.
Duraluminiu: avioane, automobile, nave, biciclete etc.
sfârşit
15
