Breaking News
QUESTION 1 You have a hybrid Exchange Server 2016 organization. Some of the mailboxes in the research department are hosted on-premises. Other mailboxes in the research department are stored in Microsoft Office 365. You need to search the mailboxes in the research department for email messages that contain a specific keyword in the message body. What should you do? A. From the Exchange Online Exchange admin center, search the delivery reports. B. Form the on-premises Exchange center, search the delivery reports. C. From the Exchange Online Exchange admin SY0-401 exam center, create a new In-Place eDiscovery & Hold. D. From the Office 365 Compliance Center, create a new Compliance Search. E. From the on-premises Exchange admin center, create a new In-Place eDiscovery & Hold. Correct Answer: E QUESTION 2 You have an Exchange Server 2016 organization. You plan to enable Federated Sharing. You need to create a DNS record to store the Application Identifier (AppID) of the domain for the federated trust. Which type of record should you create? A. A B. CNAME C. SRV D. TXT Correct Answer: D QUESTION 3 Your company has an Exchange Server 2016 200-310 exam Organization. The organization has a four- node database availability group (DAG) that spans two data centers. Each data center is configured as a separate Active Directory site. The data centers connect to each other by using a high-speed WAN link. Each data center connects directly to the Internet and has a scoped Send connector configured. The company's public DNS zone contains one MX record. You need to ensure that if an Internet link becomes unavailable in one data center, email messages destined to external recipients can 400-101 exam be routed through the other data center. What should you do? A. Create an MX record in the internal DNS zone B. B. Clear the Scoped Send Connector check box C. Create a Receive connector in each data center. D. Clear the Proxy through Client Access server check box Correct Answer: AQUESTION 4 Your network contains a single Active Directory forest. The forest contains two sites named Site1 and Site2. You have an Exchange Server 2016 organization. The organization contains two servers in each site. You have a database availability group (DAG) that spans both sites. The file share witness is in Site1. If a power failure occurs at Site1, you plan to mount the databases in Site2. When the power is restored in Site1, you Cisco CCNP Security 300-207 exam SITCS need to prevent the databases from mounting in Site1. What should you do? A. Disable AutoReseed for the DAG. B. Implement an alternate file share witness. C. Configure Datacenter Activation Coordination (DAC) mode. D. Force a rediscovery of the EX200 exam network when the power is restored. Correct Answer: C QUESTION 5 A new company has the following: Two offices that connect to each other by using a low-latency WAN link In each office, a data center that is configured as a separate subnet Five hundred users in each office You plan to deploy Exchange Server 2016 to the network. You need to recommend which Active Directory deployment to use to support the Exchange Server 2016 deployment What is the best recommendation to achieve the goal? A. Deploy two forests that each contains one site and one site link. Deploy two domain controllers to each forest. In each forest configure one domain controller as a global catalog server B. Deploy one forest that contains one site and one site link. Deploy four domain controllers. Configure all of the domain controllers as global catalog servers. C. Deploy one forest that contains two sites and two site links. Deploy two domain controllers to each site in each site, configure one domain controller as a global catalog server D. Deploy one forest that contains two sites and one site link. Deploy two domain controllers to each site. Configure both domain controllers as global catalog servers Correct Answer: C QUESTION 6 How is the IBM Content Template Catalog delivered for installation? A. as an EXE file B. as a ZIP file of XML files C. as a Web Appli cati on Archive file D. as a Portal Application Archive file Correct Answer: D QUESTION 7 Your company has a data center. The data center contains a server that has Exchange Server 2016 and the Mailbox server role installed. Outlook 300-101 exam anywhere clients connect to the Mailbox server by using thename outlook.contoso.com. The company plans to open a second data center and to provision a database availability group (DAG) that spans both data centers. You need to ensure that Outlook Anywhere clients can connect if one of the data centers becomes unavailable. What should you add to DNS? A. one A record B. two TXT records C. two SRV records D. one MX record Correct Answer: A QUESTION 8 You have an Exchange Server 2016 EX300 exam organization. The organization contains a database availability group (DAG). You need to identify the number of transaction logs that are in replay queue. Which cmdlet should you use? A. Test-ServiceHealth B. Test-ReplicationHealth C. Get-DatabaseAvailabilityGroup D. Get-MailboxDatabaseCopyStatus Correct Answer: D QUESTION 9 All users access their email by using Microsoft Outlook 2013 From Performance Monitor, you discover that the MSExchange Database\I/O Database Reads Average Latency counter displays values that are higher than normal You need to identify the impact of the high counter values on user connections in the Exchange Server organization. What are two client connections 400-051 exam that will meet performance? A. Outlook on the web B. IMAP4 clients C. mobile devices using Exchange ActiveSync D. Outlook in Cached Exchange ModeE. Outlook in Online Mode Correct Answer: CE QUESTION 10 You work for a company named Litware, Inc. that hosts all email in Exchange Online. A user named User1 sends an email message to an Pass CISCO 300-115 exam - test questions external user User 1 discovers that the email message is delayed for two hours before being delivered. The external user sends you the message header of the delayed message You need to identify which host in the message path is responsible for the delivery delay. What should you do? A. Review the contents of the protocol logs. B. Search the message tracking logs. C. Search the delivery reports 200-355 exam for the message D. Review the contents of the application log E. Input the message header to the Exchange Remote Connectivity Analyzer Correct Answer: E QUESTION 11 You have an Exchange Server 2016 organization. The organization contains three Mailbox servers. The servers are configured as shown in the following table You have distribution group named Group1. Group1 contains three members. The members are configured as shown in the following table. You discover that when User1 sends email messages to Group1, all of the messages are delivered to EX02 first. You need to identify why the email messages sent to Group1 are sent to EX02 instead. What should you identify? A. EX02 is configured as an expansion server. B. The arbitration mailbox is hosted 300-320 exam on EX02.C. Site2 has universal group membership caching enabled. D. Site2 is configured as a hub site. Correct Answer: A
Home / Física / Lei de Fourier

Lei de Fourier

PUBLICIDADE

A lei de Fourier, como o próprio nome indica, foi estabelecida em 1811 pelo matemático e físico francês Jean Baptiste Joseph, mais conhecido por barão de Fourier. Este publicou uma teoria de propagação do calor, onde introduziu as séries trigonométricas (séries de Fourier).

A lei de Fourier constitui uma lei empírica, isto é, estabelecida a partir da experiência e descreve a teoria da condutibilidade calorífica em regimes de temperaturas estacionárias e variáveis e resolve diversos problemas: parede, barra, esfera, entre outros.

Considera-se uma barra maciça de um dado material, com secção reta constante de área A e comprimento l. Imagina-se ainda que a superfície lateral da barra está termicamente isolada, não havendo portanto trocas de calor com o exterior através dela.

A lei de Fourier permite quantificar a transmissão de calor entre os extremos da barra em regime permanente (estacionário), em função das dimensões da barra, das características do material de que ela é feita e ainda das temperaturas nos seus extremos.

A equação que traduz a lei de Fourier é: Q = k x A x (TD-TE)/l, em que Q é o débito de calor de D para E, A é a área da secção reta, l o comprimento da barra, TD e TE as temperaturas nos extremos da barra e k é a condutibilidade térmica do material de que é feita a barra.

A condutibilidade térmica de um material é uma propriedade física desse material e existem tabelas que indicam os valores de k para os diferentes materiais.

Fonte: www.infopedia.pt

Lei de Fourier

Seja J a densidade de corrente de energia (energia por unidade de área e por unidade de tempo), que é estabelecida na barra devido a diferença de temperaturas entre dois pontos da mesma. A lei de Fourier afirma que há uma proporcionalidade entre o fluxo de energia J e o gradiente de temperatura.

Lei de Fourier

Sendo K uma constante característica do material denominada condutividade térmica.

Lei de Fourier

Consideremos um elemento da barra de comprimento dx e secção S. A energia que entra no elemento de volume na unidade de tempo é JS, e a que sai é J’S. A energia do elemento varia, na unidade de tempo, de uma quantidade igual a diferença entre o fluxo entra e o fluxo que sai.

Lei de Fourier

Esta energia, é empregada para mudar a temperatura do elemento. A quantidade de energia absorvida ou cedida (na unidade de tempo) pelo elemento é igual ao produto da massa deste elemento pelo calor específico e pela variação de temperatura.

Lei de Fourier

Igualando ambas as expressões, e tendo em conta a lei de Fourier, obtemos a equação diferencial que descreve a condução térmica

Lei de Fourier

 

Solução analítica

Suponhamos uma barra metálica de comprimento L, conectada por seus extremos a duas fontes de calor a temperaturas Ta e Tb respectivamente. Seja T0 a temperatura inicial da barra quando conectamos as fontes aos extremos da barra.

Lei de Fourier

Ao cabo de certo tempo, teoricamente infinito, que na prática depende do tipo de material que empregamos, é estabelecido o estado estacionário no qual a temperatura de cada ponto da barra não varia com o tempo. Este estado é caracterizado por um fluxo J constante de energia. A lei de Fourier estabelece que a temperatura variará linearmente com a distância x a origem da barra.

Lei de Fourier

Para descrever o estado transitório buscamos uma solução da forma T(x, t)=F(xG(t), variáveis separadas

Lei de Fourier

O sinal negativo assegura o caráter transitório.

Integramos a primeira equação diferencial

Lei de Fourier

Integramos a segunda equação diferencial

Lei de Fourier

É uma equação diferencial similar a de um MHS, cuja solução é a·sen(ωr+δ)

A temperatura em qualquer ponto x ao longo da barra, em um instante determinado, T(x, t) é a solução da equação diferencial, que é uma combinação de dois termos, o que corresponde ao regime permanente mais o do regime transitório.

Lei de Fourier

Condições de contorno

Em x=0, T(0, t)=Ta, temperatura fixa do extremo esquerdo da barra

Lei de Fourier

Em x=L, T(L, t)=Tb, temperatura fixa do extremo direito da barra

Lei de Fourier

O regime variável geral de temperaturas da barra é

Lei de Fourier

Distribuição inicial de temperaturas

Somente, resta por determinar os coeficientes an, identificando esta solução com a distribuição inicial de temperaturas na barra T(x, 0)=T0 no instante t=0.

Lei de Fourier

Mais abaixo, são proporcionados os detalhes do cálculo dos coeficientes an do desenvolvimento em série ao leitor interessado.

A temperatura em qualquer ponto da barra x, em um instante t, é composta da soma de um termo proporcional a x, e de uma série rapidamente convergente que descreve o estado transitório.

Lei de Fourier

O valor de α=K/(ρc) nos da uma medida da rapidez com a qual o sistema alcança o estado estacionário. Quanto maior seja α mais rápido é alcançado o estado estacionário

Fonte: www.fisica.ufs.br

Lei de Fourier

Lei de Fourier

O fator de proporcionalidade k (condutividade térmica) que surge da equação de Fourier é uma propriedade de cada material e vem exprimir a maior ou menor facilidade que o material apresenta à condução de calor.

Os valores numéricos de k variam em extensa faixa dependendo da composição química, estado físico e temperatura dos materiais. Quando o valor de k é elevado o material é considerado condutor térmico e, caso contrário, isolante térmico. Com relação à temperatura, em alguns materiais como o alumínio e o cobre, k varia muito pouco com a temperatura, porém em outros, como alguns aços, k varia significativamente com a temperatura. Nestes casos, adota-se comumente como solução de engenharia um valor médio de k em um intervalo de temperatura. A variação da condutividade térmica com a temperatura é mostrada na figura abaixo para alguns materiais.

Lei de Fourier

Fonte: www.descolando.com.br

 

 

 

Conteúdo Relacionado

Veja também

Lei de Faraday

PUBLICIDADE No estudo de circuitos elétricos podemos observar que a presença de uma diferença de …

Lei de Ampère

PUBLICIDADE Introdução O estudo da corrente elétrica dentro do eletromagnetismo é muito importante para estudar …

Lei Zero da Termodinâmica

PUBLICIDADE O que é a Lei Zero da Termodinâmica? Na natureza todos os corpos sofrem …

Deixe uma resposta

O seu endereço de e-mail não será publicado. Campos obrigatórios são marcados com *

Time limit is exhausted. Please reload the CAPTCHA.

QUESTION 1 You are managing a SharePoint farm in an Active Directory Domain Services (AD DS) domain. You need to configure a service account to use domain credentials. What should you do first? A. Configure the service account to use a domain user account. B. Register the domain credentials in the Farm Administrators group. C. Configure the service account to use a local user account. D. Register the domain credentials as a SharePoint managed account. Correct Answer: D Explanation QUESTION 2 A company named Contoso, Ltd. has a SharePoint farm. The farm has one Search service application configured. The Search service application contains five crawl databases, all of which contain content. Contoso plans to crawl knowledge base content from its partner company Litware, Inc. The knowledge base content must be stored in a dedicated crawl database.https://www.pass4itsure.com/az-103.html You need to configure crawling. What should you do? A. Add a crawl database that contains the Litware knowledge base to the existing Search service application. B. Provision a new Search service application. Configure the service application to crawl the Litware knowledge base content. C. Set the MaxCrawlDatabase parameter to 6. D. Create a dedicated Microsoft SQL Server instance for the Litware crawl database. Correct Answer: B Explanation Explanation/Reference: https://www.pass4itsure.com/az-9002.html The maximum number of crawl databases is 5 per Search service application so we need another Search service application. This maximum limit is increased to 15 with an Office 2013 update but the question doesn't mention that this update is installed so we have to assume the question was written before the update was released. https://www.pass4itsure.com/az-300.html QUESTION 3 A company uses SharePoint 2013 Server as its intranet portal. The Marketing department publishes many news articles, press releases, and corporate communications to the intranet home page. You need to ensure that the Marketing department pages do not impact intranet performance. Which two actions should you perform? (Each correct answer presents part of the solution. Choose two.) A. In Central Administration, set up a User Policy for the Super User and Super Reader accounts. B. Configure IIS to use the Super User and Super Reader accounts for caching. C. Use the Farm Configuration Wizard to configure the Super User and Super Reader accounts. D. Use Windows PowerShell to add the Super User and Super Reader accounts. Correct Answer: AD Explanation Explanation/Reference: A: The way to correct this problem is to first create two normal user accounts in AD. These are not service accounts. You could call them domain\superuser and domain\superreader, but of course that's up to you. The domain\superuser account needs to have a User Policy set for that gives it Full Control to the entire web application. D: If you are using any type of claims based authentication you will need to use Windows PowerShell. And Windows PowerShell is the hipper more modern and sustainable option anyway. If you are using classic mode authentication run the following cmdlets on one of your SharePoint servers: $w = Get-SPWebApplication "http:///" $w.Properties["portalsuperuseraccount"] = "domain\superuser" $w.Properties["portalsuperreaderaccount"] = "domain\superreader" $w.Update() If you are using claims based authentication run these cmdlets on one of your SharePoint https://www.pass4itsure.com/n10-007.html servers: $w = Get-SPWebApplication "http:///" $w.Properties["portalsuperuseraccount"] = "i:0#.w|domain\superuser" $w.Properties["portalsuperreaderaccount"] = "i:0#.w|domain\superreader" $w.Update() Note: * If you have a SharePoint Publishing site and you check the event viewer every once in a while you might see the https://www.pass4itsure.com/70-331.html following warning in there: Object Cache: The super user account utilized by the cache is not configured. This can increase the number of cache misses, which causes the page requests to consume unneccesary system resources. To configure the account use the following command 'stsadm -o setproperty -propertynameportalsuperuseraccount -propertyvalue account -urlwebappurl'. The account should be any account that has Full Control access to the SharePoint databases but is not an application pool account. Additional Data: Current default super user account: SHAREPOINT\system This means that the cache accounts for your web application aren't properly set and that there will be a lot of cache misses. If a cache miss occurs the page the user requested will have to be build up from scratch again. Files and information will be retrieved from the database and the file system and the page will be rendered. This means an extra hit on your SharePoint and database servers and a slower page load for your end user. Reference: Resolving "The super user account utilized by the cache is not configured." QUESTION 4 You are managing a SharePoint farm. Diagnostic logs are rapidly consuming disk space. You need to minimize the amount of log data written to the disk. Which two actions should you perform? (Each correct answer presents part of the solution. Choose two.) A. Set the log event level to Information. B. Set the log event level to Verbose. C. Set the log trace level to Medium. D. Set the log trace level to Verbose. E. Set the log event level to Warning. F. Set the log trace level to Monitorable. Correct Answer: EF Explanation Explanation/Reference: E: Event Levels Warning, Level ID 50 Information, Level ID: 80 Verbose, Level ID: 100 F: Trace levels: Monitorable: 15 Medium: 50 Verbose: 100 Note: When using the Unified Logging System (ULS) APIs to define events or trace logs, one of the values you must supply is the ULS level. Levels are settings that indicate the severity of an event or trace and are also used for throttling, to prevent repetitive information from flooding the log files. Reference: Trace and Event Log Severity Levels QUESTION 5 A company's SharePoint environment contains three web applications. The root site collections of the web applications host the company intranet site, My Sites, and a Document Center. SharePoint is configured to restrict the default file types, which prevents users from uploading Microsoft Outlook Personal Folder (.pst) files. The company plans to require employees to maintain copies of their .pst files in their My Site libraries. You need to ensure that employees can upload .pst files to My Site libraries. In which location should you remove .pst files https://www.pass4itsure.com/70-342.html from the blocked file types? A. The File Types area of the Search service application section of Central Administration B. The General Security page in the site settings for the site collection C. The Blocked File Types page in the site settings for the site collection D. The General Security section of the Security page of Central Administration Correct Answer: D Explanation