Recommended for SysAdmins:
20 Linux Server Hardening Security Tips.
Why recommend? i) New & valuable information (nothing obvious), ii) Detailed instructions (mostly) for those who may not be familiar, iii) Written well (writing style does not appear to be a personal blog, but an article of some magazine).
Nothings is done. Everything in the world remains to be done or done over.
The greatest picture is not yet painted, the greatest play isn’t written, the greatest poem is unsung. There isn’t in all the world a perfect railroad, nor a good government, nor a sound law. Physics, mathematics, and especially the most advanced and exact of the sciences, are being fundamentally revised. Chemistry is just becoming a science; psychology, economics, and sociology are awaiting a Darwin, whose work in turn awaiting an Einstein.
If the rah-rah boys in our colleges could be told this, they might not all be specialists in football, parties, and unearned degrees. They are not told it, however; they are told to learn what is known. This is nothing.
(Lincoln Steffens, 1931)
(quoted from How to Get Ideas by Jack Foster)
This was said about 80 years ago! Yet, it is still relevant today. This quote was something that I have wanted to tell my students if I ever get a chance to…
Scientists want faster, more powerful high-performance supercomputers to simulate complex physical, biological, and socioeconomic systems with greater realism and predictive power. In May, Los Alamos scientists doubled the processing speed of the previously fastest computer.Roadrunner, a new hybrid supercomputer, uses a video game chip to propel performance to petaflop/s speeds capable of more than a thousand trillion calculations per second.”The computer is a speed demon. It will allow us to solve tremendous problems,” said Thomas DAgostino, head of the National Nuclear Security Administration, which oversees nuclear weapons research and maintains the warhead stockpile.The computer might also have many medical and science applications, including developing biofuels or discovering drug therapies.
Continue reading: Computing::Worlds Fastest Computer::Los Alamos Lab.
There is a paper that is very closely related to our work on RFV. Question is how do they differ?
First terminology. Microarchitecture-level masking is hardware-dependent portion whereas architecture-level masking is software-dependent. Then AVF captures both, while their PVF is claimed to capture only the latter. “Therefore, PVF is impacted only by changes to the binary or to input data and not by changes in hardware.” That’s it. It does not really say about how to statically estimate the PVF without actually running the program.
But this paper is important in that it establishes the needs for our static estimation techniques.
The architectural vulnerability factor (AVF) of a hardware structure is the probability that a fault in the structure will affect the output of a program. AVF captures both microarchitectural and architectural fault masking effects; therefore, AVF measurements cannot generate insight into the vulnerability of software independent of hardware. To evaluate the behavior of software in the presence of hardware faults, we must isolate the software-dependent (architecture-level masking) portion of AVF from the hardware-dependent (microarchitecture-level masking) portion, providing a quantitative basis to make reliability decisions about software independent of hardware. In this work, we demonstrate that the new program vulnerability factor (PVF) metric provides such a basis: PVF captures the architecture-level fault masking inherent in a program, allowing software designers to make quantitative statements about a program’s tolerance to soft errors. PVF can also explain the AVF behavior of a program when executed on hardware; PVF captures the workload-driven changes in AVF for all structures. Finally, we demonstrate two practical uses for PVF: choosing algorithms and compiler optimizations to reduce a program’s failure rate.
by Sridharan, V.; Kaeli, D.R.;
Dept. of Electr. & Comput. Eng., Northeastern Univ., Boston, MA
This paper appears in: High Performance Computer Architecture, 2009. HPCA 2009. IEEE 15th International Symposium on
via IEEE Xplore – Eliminating microarchitectural dependency from Architectural Vulnerability.
A feature to implement. We want to have member-only items in the top menu line. I think this is a fantastic idea. We’ll do this later..
—————————–
Create a menu for private pages and posts in WordPress
Posted by branko in General | 14 Comments
Recently I was working on a project that required a members menu on sidebar. Idea was to mark some pages and posts in WordPress as a private ones. All those marked as private are not to be accessible to all others, unregistered users, or even some registered that do not belong to some assigned role. WordPress default behavior for posts and pages is not to show up on menu if you are not registered user, which is good. However, another WordPress default behavior is to show only private posts on sidebar menu while logged in. Meaning that pages marked as private do not show up on the menu when logged in. This is not so good. I needed a solution that will list private pages on my menu as well. After few minutes of unsuccessful Google search, i decided to write my own solution. It really wasn’t that difficult. It all came down to two existing WordPress functions, current_user_can(‘some_role’) and $wpdb->get_results($some_query).
/*show pages and post mixed on menu
$menu_type = post ->show posts only
$menu_type = page ->show pages only
*/
if(current_user_can($user_role)) {
global $wpdb;
$html = null;
if($menu_type != 'all') {
$menu_query = "post_status='private' AND post_type='". $menu_type ."'";
}
else if($menu_type == 'all') {
$menu_query = "post_status='private'";
}
$query = "SELECT * FROM $wpdb->posts WHERE ". $menu_query;
$pages = $wpdb->get_results($query);
$html .= '
if($page->post_parent == 0) {$html .= '
';}
else if($page->post_parent != 0) {
$html .= '
';
$html .= '
';
}
}
$html .= '
';
return $html;
}
else {
$html = '
We are sorry, but only '. $user_role .' role user can access this area
';
# return $html;
return false;
}
}
?>
via Create a menu for private pages and posts in WordPress | ActiveCodeline.
Thanks to many people who have contributed to this homepage, with ideas/suggestion or actual work.
Also feel free to give any new suggestions you may have about this homepage. 🙂
We are actively seeking motivated graduate students to join the very creative team.
Contact us if interested.
Sep. 8, Introduction to Intellectual Property and patent attorney
Speaker: Yongjoon Jeon, Taebaek Patent & Law Firm
Time and Place: 16:00-17:00, E104
Oct. 27, Engineers, Dream and Dream Big!
Speaker: Prof. Jongwon Kim, SNU
Time and Place: 16:00-17:00, E104
•HTM(Hierarchical Temporal Memory) : Not programmed & not different algorithms for different problem.
1) Discover cause
– Find relationships at inputs.
– Possible cause is called “belief”.
2) Infer causes of novel input
– Inference : Similar to pattern recognition
– Ambiguous -> Flat.
– HTMs handle novel input both during inference & training
3) Make predictions
– Each node store sequences of patterns
+ current input -> Predict what would happen next.
4) Direct behavior : Interact with world.
How do HTMs discover and infer causes?
Why is a hierarchy important?
1) Shared representations lead to generalization and storage efficiency.
2) The hierarchy of HTM matches the spatial and temporal hierarchy of the real world.
3) Belief propagation ensures all nodes quickly reach the best mutually compatible beliefs.
– Belief propagation calculates the marginal distribution for
each unobserved node, conditional on any observed nodes.
4) Hierarchical representation affords mechanism for attention
How does each node discover and infer causes?
Assigning causes.
Most common sequence of pattern are assigned.
Assigned causes are used for prediction, behavior etc.
Why is time necessary to learn?
•Pooling(many-one) method
– Overlap
Several images of watermelons are overlapped in one picture
– Learning of sequence : HTM uses this way.
– Reference
Hierarchical Temporal Memory – Concepts, Theory, and Terminology by Jeff Hawkins and Dileep George, Numenta Inc.