A tensor field is a mathematical object that assigns a tensor to each point in a space, such as a manifold or a vector space. Tensors are multidimensional arrays of numbers that represent certain geometric or physical properties. They generalize scalars (which are 0th-order tensors), vectors (1st-order tensors), and matrices (2nd-order tensors). A general tensor field can have components that vary in both magnitude and direction at each point in space. Unlike scalars and vectors, which have single numbers or arrows associated with each point, tensors can represent more complex relationships, such as stress, strain, curvature, or electromagnetic fields. For example, in general relativity, the metric tensor field describes the curvature of spacetime. In fluid dynamics, the stress tensor field describes how forces are distributed within a fluid. In materials science, the strain tensor field describes how materials deform under stress. In summary, a tensor field is a mathematical object that assigns a tensor to each point in a space, and a general tensor field can represent complex relationships or properties that vary across that space.
Tensor Field was last modified: March 30th, 2024 by
Temperature vs wind
- Temperature as a Scalar Field: Temperature is a scalar quantity, meaning it has magnitude but not direction. In a given region of space, temperature can vary from point to point, creating what is called a scalar field. Each point in space has a specific temperature value associated with it, but there is no directionality associated with those values.
- Wind as a Vector Field: Wind, on the other hand, is a vector quantity, meaning it has both magnitude and direction. Wind speed tells you how fast the wind is blowing, and wind direction tells you where it’s blowing from. Together, these two components create a vector field, where at each point in space, there is a vector representing the wind speed and direction.
So, in summary, temperature behaves as a scalar field because it only has magnitude, while wind behaves as a vector field because it has both magnitude and direction.
Temperature vs wind was last modified: March 30th, 2024 by
Ubuntu 18.04 LTS : OpenLDAP : LDAP over SSL/TLS
root@dlp:~#
cp /etc/ssl/private/server.key \
/etc/ssl/private/server.crt \ /etc/ssl/certs/ca-certificates.crt \ /etc/ldap/sasl2/ root@dlp:~# chown openldap. /etc/ldap/sasl2/server.key \
/etc/ldap/sasl2/server.crt \ /etc/ldap/sasl2/ca-certificates.crt root@dlp:~#
vi mod_ssl.ldif
# create new
dn: cn=config changetype: modify add: olcTLSCACertificateFile olcTLSCACertificateFile: /etc/ldap/sasl2/ca-certificates.crt - replace: olcTLSCertificateFile olcTLSCertificateFile: /etc/ldap/sasl2/server.crt - replace: olcTLSCertificateKeyFile olcTLSCertificateKeyFile: /etc/ldap/sasl2/server.key root@dlp:~# ldapmodify -Y EXTERNAL -H ldapi:/// -f mod_ssl.ldif
SASL/EXTERNAL authentication started SASL username: gidNumber=0+uidNumber=0,cn=peercred,cn=external,cn=auth SASL SSF: 0 modifying entry "cn=config" |
[3] | Configure LDAP Client If you’d like to make sure the connection between LDAP server and client is encrypted, use tcpdump and other network capture software on LDAP server. |
root@www:~#
echo “TLS_REQCERT allow” >> /etc/ldap/ldap.conf
root@www:~#
vi /etc/ldap.conf
# line 261: uncomment
ssl start_tls root@www:~#
logout www login: ubuntu # LDAP user Password: Last login: Tue Jun 5 11:22:06 JST 2018 on ttyS0 Welcome to Ubuntu 18.04 LTS (GNU/Linux 4.15.0-20-generic x86_64) * Documentation: https://help.ubuntu.com * Management: https://landscape.canonical.com * Support: https://ubuntu.com/advantage System information as of Tue Jun 5 15:05:32 JST 2018 System load: 0.0 Processes: 93 Usage of /: 6.4% of 28.45GB Users logged in: 0 Memory usage: 3% IP address for ens3: 10.0.0.31 Swap usage: 0% * Meltdown, Spectre and Ubuntu: What are the attack vectors, how the fixes work, and everything else you need to know - https://ubu.one/u2Know 16 packages can be updated. 8 updates are security updates. ubuntu@www:~$ # logined |
Source: Ubuntu 18.04 LTS : OpenLDAP : LDAP over SSL/TLS : Server World
Ubuntu 18.04 LTS : OpenLDAP : LDAP over SSL/TLS was last modified: March 27th, 2024 by
Custom AF Case for Canon 5D Mark III for birds in flight
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AC Digital Multifunction Meter Watt Power Volt Amp TTL Current Test Module PZEM-004T With Coil 0-100A 80-260V AC For Arduino – AliExpress
AC Digital Multifunction Meter Watt Power Volt Amp TTL Current Test Module PZEM-004T With Coil 0-100A 80-260V AC For Arduino – AliExpress was last modified: March 23rd, 2024 by
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https://www.dxomark.com/samsung-galaxy-s22-ultra-exynos-camera-test/
Samsung Galaxy S22 Ultra (Exynos) Camera test was last modified: March 23rd, 2024 by
Which lenses should you choose for your Canon EOS 5D Mark III?
https://www.dxomark.com/which-lenses-should-you-choose-for-your-canon-eos-5d-mark-iii/
Which lenses should you choose for your Canon EOS 5D Mark III? was last modified: March 23rd, 2024 by
For the Love of Physics: From the End of the Rainbow to the Edge of Time – A Journey Through the Wonders of Physics by Walter Lewin
https://www.goodreads.com/book/show/7841672-for-the-love-of-physics
For the Love of Physics: From the End of the Rainbow to the Edge of Time – A Journey Through the Wonders of Physics by Walter Lewin was last modified: March 22nd, 2024 by
Обичен кос
https://mk.wikipedia.org/wiki/%D0%9E%D0%B1%D0%B8%D1%87%D0%B5%D0%BD_%D0%BA%D0%BE%D1%81
Обичен кос was last modified: March 17th, 2024 by
Common blackbird
Common blackbird was last modified: March 17th, 2024 by
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One Life (2023) was last modified: March 16th, 2024 by
Proxmox Virtual Environment
Source: Proxmox Virtual Environment – Wikipedia
Proxmox Virtual Environment was last modified: March 11th, 2024 by