## Saudi Arabia on its way to introducing e-visas

For those who do not yet know, Saudi Arabia, known for its inaccessibility, has just a few days ago introduced a new e-Visa system for a handful of countries, including the entire Schengen area, the US and Australia it can do so without a fight.

Regarding the question, it was not specific whether or not I could do Umrah with this type of visa, so can Umrah be done with it?

## Samsung Galaxy S 10 – Some websites can not be loaded via USB tethering

I'm sharing the Internet from my Samsung Galaxy S10 + to my HP Pavilion 15 n208tx laptop via USB tethering. Surf speeds of up to 10 Mbps are achieved on my phone, but tethering can not load many websites. I am using the Tethered Type C USB cable supplied with my phone.

Example of strange behavior:

www.instagram.com

www.codeforces.com

www.amazon.in

## ag.algebraic geometry – possible context for this "seal-like" modular mold construction?

The following construction of a Grade 2 seal modular form has arisen in my research. I'm outside the worlds of automorphic forms and number theory, wondering if they resemble anything familiar or interesting.

To let $$F ( tau, z, sigma)$$ Be a (meromorphic) grade 2 seal modular weight form $$k> 0$$, and let $$r in mathbb {Z} _ {> 0}$$, I was forced to look at the following meromorphic function on the seal hemisphere $$mathbb {H} _ {2}$$:

$$Phi_ {r} ( tau, z, sigma): = prod_ {d | r} F large (d tau, z, tfrac {6} {d} sigma large).$$

Has such a design been investigated before or has it been created somewhere? Maybe there is a context or interpretation that someone can offer? As I briefly outline below, the congruence subset is almost a seal form $$Gamma_ {0} ^ {(2)} (r) subset Sp_ {4} ( mathbb {Z})$$, Note in particular that we maintain the symmetry between $$tau$$ and $$sigma$$

From the Fourier-Jacobi extension of $$F$$it is easy to write down the corresponding extent of $$Phi_ {r}$$, Where $$Q = e ^ {2 pi i sigma}$$:

$$Phi_ {r} ( tau, z, sigma) = sum_ {m = 0} ^ { infty} Q ^ {m} varphi_ {k, m / r} ( tau, z).$$

You can show that $$varphi_ {k, m / r}$$ behave like Jacobi weight forms $$k$$ and rational index $$m / r in mathbb {Q}$$ on the group $$Gamma_ {0} (r) rtimes (r mathbb {Z} times mathbb {Z})$$, So that's almost the Fourier-Jacobi extension of a seal form, but the index and exponent of $$Q$$ differ by the factor of $$1 / r$$, In order to $$Phi_ {r}$$ Changes properly under the following conditions:

$$( tau, z, sigma) mapsto bigg ( frac {a tau + b} {c tau + d}, frac {z} {c tau + d}, sigma – frac {cz ^ {2}} { textbf {r} (c tau + d)} bigg)$$

to the $$(a, b, c, d) in gamma_ {0} (r),$$ and for $$lambda in textbf {r} mathbb {Z}$$ and $$mu in mathbb {Z}$$:

$$( tau, z, sigma) mapsto bigg ( tau, z + lambda tau + mu, sigma + frac {1} { textbf {r}} ( lambda ^ {2 } tau + 2 lambda z) bigg).$$

The factors of $$1 / r$$ which I've made bold above, seem to spoil this action that really comes from the action of $$Gamma_ {0} ^ {(2)} (r)$$ on $$mathbb {H} _ {2}$$, Is there a closely related group? $$Sp_ {4} ( mathbb {Z})$$ which I should think about instead, like similarities or something?

## How do I create a 3D grid in Unity3D?

What is a simple way to create a three-dimensional "hollow" and square grid around a center more like a cube (whose size can vary), with each cell evenly spaced (based on a value)?

Note: I can create a 2D raster, but not a 3D raster.

## Plugin Development – View specific categories of post-based user responses to the survey

I'm working on a blog that covers a wide range of interests, but I want to offer readers specific content based on their preferences.

For example, I want readers to know that they only want to read marketing and startup posts on my blog.

I need a plugin or help.

Thank you very much.

## Find URLs that redirect to a specific web site

Is there a way to find all URLs that (permanently) redirect to a specific website?

For example, www.ubercab.com redirects to www.uber.com. Therefore, I would like to find a way to determine that www.ubercab.com redirects without knowing that www.ubercab.com exists ex ante.

## pulseaudio – Sound Cracking and Popping Ubuntu 19.04

I spent a lot of time looking for a solution on the internet, but nothing seems to work. I tried these corrections

Static and crackling noise from the speakers from 19.04

Clicks and pops from the left side of the headphone in the front left / right sound test

and the pulse-audio fix but nothing worked.

My speakers just crack randomly and make sounds when they do nothing and sometimes during audio playback. I have not had this problem before and when I boot into Windows everything is fine. So I can rule out a hardware problem.

I received the Z370 AORUS Gaming 5 (Version 1.0) with the Realtek® ALC1220 codec. Connected is a 5.1 surround system from Logitech.

The problem was already in 18:04 and an upgrade to 19 did nothing to fix it.

I was just trying to connect and switch to my external Soundblaster card, but the connection to the mobo headers was maintained and the sounds persisted

## linear algebra – Show that no undistorted estimate exists

Consider the following linear regression model

$$Y = Xw + epsilon$$.

Where $$w in mathbb {R} ^ d$$. $$X in mathbb {R} ^ {(n times d)}$$, and $$epsilon sim N (0, sigma ^ 2I)$$, We want to show that, if for $$c neq 0$$ we have $$Xc = 0$$, then there is no unbiased estimator for $$cw ^ T$$,

It is easy to show that there is no linear unbiased estimator for $$c ^ Tw$$, I did the following:

Suppose our estimator is $$a ^ TY$$, This estimator is unbiased when

$$E (a ^ TY) = c ^ Tw$$,

We have

$$E (a ^ T (X)) = a ^ T X w = c ^ Tw$$ for all $$w$$, Therefore,

$$X ^ Ta = c$$.

which means, that $$c$$ is written as a linear combination of $$x_1, dots, x_n$$, Where $$X ^ T = (x_1 | x_2 | dots | x_n)$$, This contradicts our assumption that $$Xc = 0$$,

How can I extend this result to show that there is no unbiased estimator? Is the unbiased estimator (OLS) unique to this problem?

## Linux – Can a damaged internal hard drive that is currently powered on cause the operating system to stop responding?

Recently, a friend of mine had problems with his desktop PC, and more generally, the PC slowed down (Windows 7, which is not unusual for me) and had some problems, such as from time to time not responding.

The PC has two internal hard drives, one possibly damaged (but still live) and one SSD with the windows 10 installed thereon.

The hard drive was connected during these problems and also had Windows 7. When I went there and checked the PC, I found no problems at first, but did not check the disks with a tool.

I alternatively installed a Debian 10 XFCE distribution on the hard drive and left it turned on … but asked my friend to load this operating system in case of problems with his (on) windows.

I could not figure out if this first problem was caused by a temperature problem on the GPU or a disk problem or even a CPU temperature problem.

I left the PC to have the SSD as a standard hard drive and boot under Debian only if the user decides it and boots (though BIOS) from the hard drive (on which grub was installed, which also contains Windows entries).

The next day my friend told me that he had problems with the unresponsive system, while he had only been loading Windows for a few minutes … Then he tried Debian (selected from the BIOS) and had the same problem …

At first, I thought that this meant it might be a GPU problem because Windows was installed on the SSD and could not get stuck there because only one hard drive was powered but not in use. (And the problem was the same after only a few minutes of use on both hard drives and operating systems).

It is certain that this is a hardware problem.

But could it be the damaged hard drive and not the GPU?
Should I just pull the plug out of the socket and let it wait a few more days?
Or do I have to be sure that it is not a hard disk problem?

PS: I'm sorry if the question is not good here … You can ask me to delete or close it if you help me find a way to make an insecure diagnosis (eg. exclude or not exclude) I would be happy about the damaged hard drive as a reason for the problem – if this can be an issue -.
Some tools, even under Windows, or better under Debian / Linux, that could help me with testing the hardware, could be an acceptable answer.

My only question is: Could a hard drive that is powered but not used by the operating system cause an operating system-independent, unresponsive operating system?