Damage to the sub floor while scraping tile

Question: I have a question about a hardi backer sub floor.  I installed tile 8 years ago and my wife decided she wanted a diferent tile. The sub floor was laid over linoleum with a 1/4 in backer board that was installed with the house build.  So feasibly I have 1/2 inch down to the original floor.  I tore up the existing tile and it pulled a top layer of the hardi backer off in abouyt 40 % of the area in a small bathroom.  It's kind of knarled and pieces of the top layer are loose but not severely damaged to cause the backer to come from the floor.  I have screws every 8 inches so it is secured pretty well.  I have gotten advice to skim it with mortar and level it all out and then lay the tile.  I'm a little nervous about this, I don't want to do it twice.  Also, I saw Schuleter ditra product, can I just lay that down and then commence with tiling.  I think I can remove the screws and pull the whole thing with a little work but don't want to, Ha.  Any advice ?
Answer: If the damage is not significant (you mention the approximate area affected but not how deep the damage is) you could just tile right over it.
If the missing layer(s) of backer-board are significant enough so as to cause the tile to not lay level and flat, you will need to do something:

best option would be to remove and replace the damaged backer-board
the Ditra product works well but also requires a flat level surface below, so again it would depend on the nature and extent of the damage.
I have had decent luck troweling a smooth skim coat over rough surfaces and letting it cure prior to tile application, and would probably choose this method because it is the simplest/easiest, but this is a skill. Well mixed mortar with the right consistency along with careful trowel work are needed.
Answer: I would replace the missing Hardi board. Linoleum does not provide adhesion for the mortar. Screw it to the subfloor with 1/4" thinset below and tape the joints with fiberglass mesh. It will never move


How many Naruto Shippuden dubbed episodes are there?

Question: I am watching Naruto and I am currently on episode 164. How many episodes of Shippuden do they have dubbed, and are they still dubbing it?
Answer: All 500 episodes have been dubbed since October 7, 2019.

For region 1 (North America), all 500 episodes have been released since June 11, 2019.
For region 2 (UK), all 500 episodes have been released since October 7, 2019.
For region 4 (Australia/New Zealand), all 500 episodes have been released since August 7, 2019.

Source: Wikipedia.
Answer: Season 25 of Naruto Shippuden was released in January 2016 according to Viz Media's release calendar.

Also, the Naruto Shippuden Wikipedia has a list of the completed English dubbed episodes ending at episode 322. Episodes after 332 are still TBA.
Answer: As of may 21 there are 335 episodes of Naruto shippuden that have been dubbed. Many more episodes are still being made and many episodes are still being dubbed so we wont run out of Naruto content soon.


what is the difference between 'approve' and 'approbate'?

Question: Could you explain difference between them such as usage?
In my dictionary, both have almost the same meaning.
I cannot understand exactly.
Comment: A very short answer: just don't use "approbate".  [It's a very rare word](https://books.google.com/ngrams/graph?content=approve%2Capprobate&year_start=1916&year_end=2000&corpus=15&smoothing=3&share=&direct_url=t1%3B%2Capprove%3B%2Cc0%3B.t1%3B%2Capprobate%3B%2Cc0) and a lot of people won't understand what it means.
Comment: @stangdon: Quite. As I expected, searching Google Books for [**approbation sic**](https://www.google.com/search?tbm=bks&q=%22approbation+sic%22) turns up several instances where **[sic]** is included because the writer is citing someone else's incorrect use of **approbation** (where they probably should have used **opprobrium**).
Comment: As well as "rare", http://www.oxforddictionaries.com/definition/english/approbate gives it as "US". I've never seen the verb "approbate" in British English, though the noun "approbation" is used (but only in a very formal context)
Comment: For a learner, the difference is that "approve" is an actual word while "approbate" is a rare technical term.
Answer: Approbate means "to officially authorize" while approve means "agree or accept". Approbate is very formal and rather uncommon, and is usually used in official contexts such as political proceedings. Additionally, approbate refers more to the action of approving whereas approve connotes an attitude or sentiment, especially a moral judgment. Approve can also be used in context to mean "officially approve".
Examples:

"I don't approve of such revealing clothing."
"The chairman approbated our request."
"This order needs to be approved by a judge before it can be carried out."
Comment: +1 for highlighting the distinction between the action and the sentiment.  "Approve" can be the action, but "approbate" is always the action.
Answer: Approbate is more formal than approve.  In addition, its definition is more specific, describing an official approval.
Answer: I'm not very familiar with the word "approbate" so I might be missing some of the nuances. As far as I can tell, they mean the same thing, but approbate is far more formal.
For example, I might approve of a new law, but that doesn't mean it is any more or less likely to become a law. But if the government "approbates" a new law, this new law is now legally and formally approved and is the law.
As for usage, I would recommend almost always using approve. You can use "approve" anywhere you could use "approbate" but definitely not the other way around. For example:

I'm DJMcMayhem, and I approbate this message.

Sounds very strange. I would also recommend "approve" since it's a much more common word.
Answer: As you say, they both have pretty much the same meaning. They have come, via different routes, from the latin word probere, meaning to test. Approbate is slightly more official in meaning, and many english speakers would have to look it up in the dictionary to be sure of the meaning. Firefox spell checker isn't to sure about it either :-). If you want to be understood, I would stick to approve.
It's worth noting that the expression "approve of" has a slightly different meaning. Here are some examples:
The government approved the new construction project.
The government approbated the new visa requirements.

Governments are involved, they have made a decision: something very important is about to happen.
My boss approved my expenses

This is only a small decision, but something is still going to happen as a result of it.
He approved of her taste in music.

He has no control over her taste in music, nothing will happen as a result of his approval, but he likes the kind of music she likes.


Minimum path between two vertices passing through a given set exactly once

Question: Suppose I have a source node $S$, destination node $D$ and a set $A$ of intermediate nodes $P_1, P_2, \dots$ in an edge-weighted undirected graph. I want to find the vertex $P_i\in A$ that minimizes $\mathrm{dist}(S, P_i) + \mathrm{dist}(D, P_i)$?  In addition, the overall path from $S$ to $D$ should contain only one node from the set $A$.  What is an efficient algorithm for this? I don't want to go with brute-force approach.
Comment: @sjmc it isn't because the shortest path between $S$ and $D$ may shunt the set *$A$*
Comment: Is this not the same as finding the shortest path from S to D?
Comment: @sjmc I disagree. Shortest path takes all the intermediate nodes into consideration where OP is only interested in a subset of those. Projecting the graph on (S, D} union A, and then doing shortest path is also wrong because distance(S, Pi) can go through nodes not in A.
Comment: Ah I misunderstood what was meant by "intermediate nodes". You're both right, it's of course not the same.
Answer: The following answers the variant which requires passing through the set exactly once.
Make two copies of the graph. Remove all edges incident to two vertices of $A$. Orient all edges incident to $A$ in the first copy toward $A$, and all edges incident to $A$ in the second copy from $A$; other edges are bidirectional. Connect both copies of each vertex in $A$ with a zero-weight edge going from the first copy to the second copy. Now look for a shortest path between the first copy of $S$ and the second copy of $T$.
Using Dijkstra's algorithm, the complexity of this approach is $O(E+V\log V)$. In comparison, the trivial algorithm that tests all vertices in $|A|$ one at a time needs to run Dijkstra's algorithm $|A|$ times, unless the graph is unweighted, in which case one can use BFS instead in time $O(E|A|)$.

Here is an alternative solution, using only undirected graphs. Start by deleting all edges inside $A$. Add $M$ to the weight of all other edges incident to $A$, where $M$ is larger than the sum of all weights in the graph. Run Dijkstra's algorithm twice to find the shortest path between $S$ and any vertex in $A$, and between $T$ and any vertex in $A$; in both cases, the shortest path passes through no other vertex in $A$, due to our adjustment of the weights. Now go over all vertices $A$ and find the shortest path from $S$ to $T$ via a vertex in $A$.
This algorithm also runs in time $O(E+V\log V)$.

The following answers the variant which requires passing through the set at least once.
Make two copies of the graph. Connect both copies of each vertex in $A$ with an edge of zero weight. Now look for a shortest path between the first copy of $S$ and the second copy of $T$.
The complexity is $O(E+V\log V)$, or $O(E+V)$ if the original graph is unweighted (in this case, we modify the construction so that the parallel $A$-edges have unit weight; this is harmless in terms of computing the shortest path).
Comment: @YuvalFilmus , minimum number of computation is desired. But your solution [ I suppose it may work ] makes even the computation worse.
Comment: @K.Nath According to Wikipedia, Dijkstra's algorithm can be implemented in time $O(E+V\log V)$, which is better than the trivial $O(E|A|)$ solution unless the graph is very sparse and $|A|$ is very small.
Comment: How does your algorithm(s) guarantee that the output trail is actually is a path?
Answer: One way of doing this would be reducing it to |A| shortest path problems. Every shortest path would be on the subgraph G - A + {Pi} for a Pi. This will give minimum [ distance(S, Pi) + distance(D, Pi) ] for that Pi. Choose the Pi for which the shortest path is minimum.
EDIT: As @collapsar pointed out, this will only work if distance(S, Pi) does not include nodes in A-{Pi}. Not the answer you were looking for but it might give some ideas.
Comment: Consider the complete graph. Assume in path $S, P_1, \dots, P_n, D$ all edge weights are 1. Also assume that all other edge weights are 'sufficiently large' (eg $> |V(G)|^2$). your algorithm would not find the shortest path between $S$ and $D$ passing through $A$ because it had to consider all of $A$ which it doesn't.
Comment: I think your algorithm is not correct: The shortest path from $S$ to $D$ through $P_i$ may pass through some $P_j, j\not=i$. You won't capture it by computing in $(G \setminus A) \cup {P_i}$. As a border case, consider the shortest path from $S$ to $D$ in $G$ passing through _every_ $P_i$.
Comment: If it passes through Pj, then the shortest distance through Pj would be less than equal to Pi. Hence, Pi won't be chosen. My understanding of the question was that distance(S, Pi) could involve any node.
Comment: Oh I see. You are correct. My answer would only get correct answer if distance(S, Pi) should not involve any nodes in A - {Pi}.
Comment: @Tushar , you are quite right. I need such a shortest path from S to D that includes only one node from set A, i.e; I need an algorithm that can choose only one Pi from set A for which dist(S, Pi) + dist(D, Pi) is minimum. Can you give me any reference or implementation idea for this algorithm? Is it |A| shortest path algorithm ?
Comment: @Tushar , please provide some reference about |A| shortest path problem whatever you have written about in your answer.
Comment: I just meant that there will be |A| number of shortest path calls.  That can be bellman ford algorithm or any shortest path algorithmn you prefer.
Comment: @Tushar , ohh... It's general to think of |A| number of shortest path calls, but my concern is that in my application, this kind of calls should be performed again and again for several nodes [In the worst case, say for all possible pairs]. So I need a better optimized algorithm that can minimize computation.
Comment: "In the worst case, say for all possible pairs". That was the intent of my solution. It is better than brute force because you don't have to do it for all possible pairs. I understand that |A| shortest path calls can be optimized further but nothing clicks my mind at the moment (except caching graphs).


Was Shaktism prevalent in the Vedic times?

Question: Was Shaktism prevalent in Vedic times? Do Vedas praise the Supreme almighty Shakti?
Answer: I'm only answering this part of the question so consider this a partial answer:

Do Vedas praise the Supreme almighty Shakti?

Yes, the Vedas do contain hymns in praise of the Shakti. One such hymn is the Devīsūkta, also known as Aṃbhṛnīsūkta, in the Rig Veda:

I (Devi) proceed with the Rudras, with the Vasus, with the Ādityas and the Viśhvadevas; I support both Mitra and Varuṇa, Agni and Iñdra, and the two Aśvins. (Rig-Veda 10.125.1)
I support the foe-destroying Tvaśtṛ, Pūśan and Bhaga; I bestow wealth upon the institutor of the rite offering the oblation (havis) - (who is) pouring forth the libation and deserving of careful protection.(Rig-Veda 10.125.2)
I am the sovereign queen (of all Existence), the collectress of treasures, cognizant of (the Supreme Being), the chief object of worship; as such, the gods have put me in many places, abiding in manifold conditions, entering into numerous (forms). (Rig-Veda 10.125.3)
He who eats food (eats) through me; he who sees, who breathes, who hears what is spoken, does so through me; those who are ignorant of me, perish; hearken who is capable of hearing, I tell you that which is deserving of belief. (Rig-Veda 10.125.4)
I verily myself declare this which is approved of by both gods and men; whomsoever I choose, I render him an exalted one, make him a ṛṣi, make him Brahman or make him highly intelligent. (Rig-Veda 10.125.5)
I bend the bow (to fasten the bow string at its ends) for Rudra, to slay the tormenting, Brahman-hating enemy. I wage war against (hostile) men (to protect the praying ones); I have pervaded the Heaven and earth. (Rig-Veda 10.125.6)
I bring forth the paternal (heaven - abode of the manes) upon the crown (brows) of (this Supreme Being); my genesis is from the waters (cosmic - the all pervading Entity); from thence, I pervade through all beings and reach this heaven with my body. (Rig-Veda 10.125.7)
I verily myself breathe forth like the wind, issuing out form to all the created worlds; beyond the heaven, beyond the world (I Exist eternally - beyond space & time) - so vast am I in my greatness.
(Rig-Veda 10.125.8)
Answer: According to Upendrakumar Das, one great scholar on Shaktism, the answer is Yes.

Some scholars think that all the principal forms of the Vedic Gods are forms of Shakti.Tge fact is the Devas are neither males nor females.
In Rigi-Veda, Aditi has been referred to as Parama Devata. We must mention the Ratri-Sukta and Devi-Sukta also. In Vrihaddevataa, Ratri has been referred to as Kaali.
Sinivali,Raakaa, Kuhu are the names of the Vedic goddesses.Vrihaddevata treats them as alternative names of Saraswati. Shree and Lakshmi have been both considered as alternative names of the same Devi. Saraswati, Vaak, Ila--tyese Vedic goddesses wewr forms of Saraswati, as mentioned in the Veda-Samhita. In Satapatha-Brahmana, Vakdevi takes the form of a Lioness.The Sankhyana-Grihyasutra mentions Sri and Bhadrakali simultaneously. Sukra-Neetisaara provides a four armed description of Saraswati.
The name of Amvika is found in the Sukla-Yajurveda. The name of Durga is mentioned in the Taittriya-Aaranyaka. According to yaska, Agni and Aditi are the same. In Rig-Veda, we get the name of Mudgalani.
The Sweataaswatara-Upanishad mentions names of Maya or Prakiti.(Ref: Bharatiya Saktisadhanaa om Saaktasaahitya, RMIC, vol 1, chapter 4)


Sites that let you pay with two cards? (Air travel)

Question: My girlfriend and I are two poor college students saving money for trips. Are there any sites that let you pay with two cards, so we can pay for a flight? Meaning, I pay, say, $300 for the flight, then select another card (hers), and pay the other $300?
Comment: Is there some reason why you can't each buy your own ticket? Or one of you send money to the other to who buys both?
Comment: For normal airline tickets, it's an issue dependent on the specific airline rather than the site. Travel agents or sites don't actually charge your card for the ticket themselves, the number is passed on to the airline who handles payment. The exception is if it's a package.
Comment: Sounds like a job for a brick-and-mortar travel agent. Doing a money order or sending a check (if you reside in the US) should be the easier option, though. I don't think that online travel agencies want to deal with this. What if one transaction is accepted, but the other one is denied? From an IT standpoint, allowing the customer to pay with multiple cards is a nightmare. Perhaps you find an OTA that allows PayPal usage and you transfer the money to your PayPal account before booking?
Comment: Oh, wow. I had no idea :O
Comment: Have you looked into buying a prepaid card and paying with that? You can get them at grocery stores who usually split transactions easily.
Answer: I looked into this a while back because I wanted to put some portion of any trip on my Citi Prestige credit card, which has excellent trip delay coverage. After spending a lot of time researching, I found one online travel agent that allows payment with two cards: CheapOAir.com. As far as I can tell they are the only option.
I think it's also usually possible pay with two cards in person at an airline ticket office like an airport ticket counter, but sometimes there are also locations in big cities. But I don't know if that's true for every airline (or even true at all).
I decided not to use CheapOAir, because there are many complaints about their customer service, and if I remember correctly, a tendency for them to sometimes inexplicably cancel reservations. I'd suggest you do your own homework about them and make your own decision.
Also, just to see if they still allowed payment with two cards, I just did a dummy flight booking search on their site (one way NYC>MCI 7/17/18) and it missed about half of what all the other search engines showed, and what it did turn up was more expensive than elsewhere. I don't know if it's an anomaly or a consistent issue.
If you really wanna get stupid about this, you could fly Southwest, which lets you cancel flights without penalty. You could book a cheaper flight to some arbitrary place with your card, cancel it, and the value of the ticket would go into your Southwest travel bank. You could then apply the travel bank funds to the booking you really want and put the balance on her card. For other airlines, you could try experimenting with their 24-hour refund policies, or their fully flexible tickets -- if you can get them to issue you a travel certificate rather than a refund to your credit card, you might be able to accomplish the same thing.
Answer: I would rather recommend you refrain from this practice. I understand that you want to share the load and that is fair enough, but you can also do that by transferring one's share into the other's account, whenever you need to make bookings. Also, platforms like Paypal where you can add multiple cards and choose payment options by changing default payment cards can be used.
Preferably, if you are asking from the terms of earning points, then in that case, you should avoid saving the card details (by unchecking the save the card option on the payment gateway). In this case, do NOT rely on only one source (lets say only airline for both cards) for earning your points. You can split up your cards for earning points for different categories- Eg - your card for air travel and your friend's card for hotel bookings.
Thirdly, since you mentioned that you are saving money for travel, I would say, when you do that, make the most of every penny that you save, and convert it into an investment. If you are using a debit card, you can always earn miles for your expenses by using the techniques I have described on this free e-book
Secondly, if you use credit cards, you can always use miles consolidators such as Award Wallet, Trip It OR Points to consolidate all your airline miles accounts, earn and use miles which you earn by spending your hard earned travel savings.
Hope that works for you.
Regards


How can I hang up shields in my house?

Question: So I've been running around stealing all the different shields of the different holds. They looks pretty sweet and I would like to display them in my house (I currently own the one in Whiterun). I know there are weapon racks for swords and such, but is there something similar for shields? Perhaps in a different house? If not, are there any known plans for modding it in when the creation kit comes out?
Answer: Your house in Whiterun has a shield rack above the bed. You can place two weapons, one on the right and one on the left, and a shield in the middle.
Answer: Yup, Skyrim has Shield Racks too!
I know Vlindril Hall, in Markarth, has two, and they work identically to Weapon racks - taking your equipped item and mounting it on the wall.
Answer: All you have to do is take the shield that is already there (usually an iron shield) and place the one you want. You can also put weapons behind the shield too.

How can I hang up shields in my house?


Do many Japanese people speak Korean?

Question: I'd like to go to Japan but I can't speak Japanese. But I'm fluent in Korean. I know that many Korean people can speak Japanese, but can Japanese people also speak Korean?
Comment: I would encourage you to try to learn to read and speak at least a little Japanese - some phrases, and hiragana and katakana. If nothing else, you will at least recognise a Karaoke parlour when you see one!
Comment: Anecdotally: as an European, I went there on a trip. Everyone was very nice to us and we went to some rural areas where no one could speak English. They still were very polite to us and we had no problems communicating. Don't worry about the language ;)
Answer: No. Most Japanese people do NOT speak Korean. However, the English language is a required subject in the Japanese secondary education; although English education has not gone very well for Japanese people, in general, most people can understand at least a little bit of English (except, of course, the very old people). (EDIT: As commenters reminded me, there is indeed a increase in the number of young Japanese people who study Korean (in their mean time, or perhaps as a second foreign language in college), due to the popularity of Korean popular culture among the young generation. However, there are not that many of them such that you could randomly run into them on the streets.)
There are places with Korean signs (usually touristy places), but there are far more English signs than there are Korean signs, so there's no real advantage here if you read Korean. In shops frequented by tourists, there are often Korean speaking staff members; but of course, English is almost always more useful. Nevertheless, all of these are almost exclusive to Tokyo, Nagoya and Osaka metropolitan areas ("Tomeihan"), and you should expect almost no Korean signs outside of this area (perhaps some in Fukuoka as well, due to proximity to Busan).
If you are able to write some hanja (Chinese characters), however, you might be able to express simple ideas and communicate with Japanese people using them, because virtually all Japanese people know some kanji. Ability to read Chinese characters can often help you understand signs as well. But do not expect too much out of this.
There are around 1 million or so Japanese Koreans (including N/S Korean citizens living in Japan, and Japanese citizens of Korean descent), but you could not tell them apart from the ethnic Japanese, so it's likely not a good idea to try to speak Korean to random people. However, there are a few Korean ethnic enclaves in Japan (such as О̄kubo in Shinjuku Ward, Tokyo), and you'll of course have luck speaking Korean in those areas; nevertheless, none of those Korea-towns seem to be popular tourist destinations.
Comment: While not a large enough number to randomly find someone who can speak the language, due to the popularity to KPOP in Japan, there are many young people studying Korean now as well.
Comment: Also, many Japanese will understand perfectly what you say in English. Fewer people will be confident enough to answer, though.
Comment: @EricDuminil Yep, this is absolutely true. Due to my not-so-great Japanese and not-so-great hearing, sometimes Japanese people attempt to speak to me in English, but when they do so I absolutely prefer that they switch back to Japanese :-) Simply because most Japanese people are really not that great in spoken English

Do many Japanese people speak Korean?


Role based Database Schema

Question: I am designing a database for a document management app for my office. I want to get the backend right so I don't have issues in the future. Basically all users will be categorized into roles e.g, super admin, admin, staff and interns. All documents will have access restrictions e.g public(all user roles can view the document), private (only user who created it can view), role-based(this means only users with the same roles can view these documents). However, Admins and super admins can view all documents. One user can have many documents. Also user roles can be updated e.g from staff to admin etc. I will be using Postgres with Sequelize as my ORM for this project. Based on the description above, is this a good design? What can be improved? Any inputs will be appreciated.
Comment: Probably you need Groups too, e.g. all members of a team have access to a document. N.B. there are plenty of DMS already available if this is for real-world and not some kind of exercise
Answer: One problem that I see with

role-based (this means only users with the same roles can view these documents)

is that if I create a document with this type as an intern, and later get promoted to a staff position, will that document be visible to the interns or to the staff?
I'd rather set the access_type field on the Document itself, and use the DocumentPermission entity to specify which roles have access to a certain Document (if the access type is role-based).
Also (but that is my opinion, I've seen more implementations like yours), I'd put the roles (superadmin, admin, staff, intern) into a separate entity, and have the UserRole entity link to that entity instead of the role_name column. Your design might save you a join, but in the end it's less flexible.
Comment: Thanks for the shrewd observation. For this point: `"use the DocumentPermission entity to specify which roles have access to a certain Document (if the access type is role-based)"`, do you mean just adding a field like `role_permission` on the DocumentPermissions entity that specifies which role has access to the document based on the document id? And will this apply to all access types (Public, Private and Role based)?
Comment: This would only apply to Role-based access, and one DocumentPermission record would specify that (one) role X has access to (one) document Y. A document can have multiple DocumentPermission records.
Comment: Please if it's not too much to ask, can you show me an ER diagram to illustrate this? I can't picture what you're saying. Thanks..
Comment: @ss_millionaire either [this](https://i.stack.imgur.com/di3Tq.png) or [this](https://i.stack.imgur.com/hCfl1.png) (if you go for a separate Role entity). I don't have any ER software to show the foreign keys, but I hope it's clear.
Answer: This design is a sound start:

you have users
users can have several roles
documents are related to users (I assume that a user is the owner of his documents whatever his role are or will be)
documents can have several access types

But I think it is incomplete.  These two things are missing:

for sure:  you said you wanted the possibility of having role based accesses, i.e. give permissions on a document to specific roles.  This means that you should have an optional relation between DocumentPermission and UserRoles as well.
may be:  unless you want to handle "public" and "private" access and their exceptions for administrators and super-users (and may be later for auditors) in a hard coded way (how are these special roles identified, by the way ?), you'd need a AccessPolicy table that makes the relation between an access-type and the roles which have special privileges for the related documents.
Comment: Thanks. and sorry for the late acknowledgement. I understand the second point perfectly. But for the first point, how do i establish that relationship between `DocumentPermission` and `UserRoles`? I'm not sure how to implement that.
Comment: Suppose you don't implement the second point.  You'll have role such as "staff" and "intern".  You'll have permissions such as "public", "private", but also role based permission such as "staff only" and "intern only".  So you must have an optional relation between `DocumentPermission` and `UserRoles`. You could implement this using an nullable column in `DocumentPermission` containing the id of the related role (implies that one such permission gives access to one role).  If you implement the second point, you'll not need this, because the many to many relation allows to define it also.
Answer: As per my knowledge we should give permission to roles not to documents or users .As per ur requirement in future if you add any new role and tag it to users base u have it should work. RBAC algorithm google it u can find n no.of docs on it

Role based Database Schema


Suggest a line for a player who does not want to be dragged into the Sicilian

Question: I am a very bad Sicilian player and I am easily played out of book in the Sicilian defense. I need a line that would prevent my opponents fom going into the Sicilian defense. I have tried c4, but sometimes it transposes into a Sicilian with the Maroczy bind. I know d4 is good, but are there any other suggestions I could play?
Answer: You could transpose to the Botvinnik English System:
<code>[FEN ""]

1. e4 c5 2. c4
</code>
Because it is a system opening, you usually put your pieces on the same squares regardless of what Black does. For example:
<code>[FEN ""]

1. e4 c5 2. c4 Nc6 3. Nc3 g6 4. g3 Bg7 5. Bg2 Nf6 6. Nge2 O-O 7. O-O d6 8. d3
</code>
The usual piece placements are:

Fianchettoed kingside castle
Knights on c3 and e2
Queen on d2 and bishop on e3
A rook off the a1-h8 diagonal, e.g. on b1

Evaluating this opening we see that:

It's a system opening, so it is easy to learn. But it doesn't give the best chances to win
The Botvinnik Triangle, pawns on c4, d3 and e4, allow White to play on any sector of the board. For example: breaking with d4, attacking with f4 or gaining space with b4
White has a hole on d4, which might be quite tender

See also the YouTube video Chess Opening for White: Botvinnik-English System against the Sicilian Defence.
Comment: Thabk you very much.  Ill try this line.
Answer: The main problem (at least on amateur level) of White in the Open Sicilian (i.e. 2. Nf3 and 3. d4) is indeed that you need to know a lot of systems/lines that Black can throw at you (see also this answer which recommends the Grand Prix attack with 2. Nc3 and 3. f4 (or the other way around)).
On my former club, 2. c3, the Alapin variation was quite popular. Black has a few options, but they all lead to positions which do not resemble the Sicilian main lines they are familiar with. The main options are:
2... d5 will usually lead into position where White has an IQP, with the corresponding development and space advantage. Black can of course hold on but it is rather hard for him/her to play for a win.
2... Nf6 3. e5 Nd5 is the other main line, where White builds a pawn center. It reminds a bit of the Alekhine Defense. This line sometimes transposes into the Morra-Smith gambit after a later d4 by White.
Answer: I would be tempted to say : don't enter the sicilian, don't play e4, but as you mentioned yourself sicilian positions can occur in other openings. So, there is no way out: you will have to master several positions transposing into sicilian territory (partially or totally), would it be only for your own sake and progress in chess. What you can do is playing different style positions. The sicilian has a wide scope of possibilities (closed, b3 and so on). Anyway, avoiding open sicilian will impede your progress (tactically, positionally and strategically). What you should do is, if you still want to avoid open sicilians, learn to pay less studied and theoretically analysed positions, possibly avoiding potential (but not sure) immediate defeats. Bad Bishop's proposal is interesting but entails you do not play e4 at the first move. Furthermore, with black you could anyway have to face a reversed sicilian. Sicilian structures are fairly universal in normal or reversed order. You cannot avoid them all, you can just choose less studied options and as a consequence avoid learning certain types of positions and so impede yourself getting a view of chess as a whole, whether tactically, positionally and strategically. You must understand that not practising certain types of major positional complexes will handicap your understanding of other types of position you like.
Have a nice day!


Exploit Development with python

Question: Are there any libraries to help developing exploits in python, like representing hex string or assembling/disassembling x86 instructions?
Comment: this is a very broad question... (representing hex or disassembling just takes a few lines)
Answer: if you want to develop exploits in Python, this book may help:
http://my.safaribooksonline.com/book/-/9781597497299/chapter-9-exploitation-scripting/building_exploits_with_python
If you need to generate big chunks of asm PeachPy might help:
PeachPy https://github.com/Maratyszcza/PeachPy
You can also compile python to C, and use a C compiler to get things down to assembly
https://stackoverflow.com/questions/10660266/python-program-into-a-standard-assembly
Or you could write most of your program in Python, and use a variety of methods to get inline assembly in:
https://stackoverflow.com/questions/6040932/executing-assembler-code-with-python
That means less asm for you.
To be honest, you will be better of rolling with the punches and properly learning ASM. It is hard, but well worth the trouble. Try starting with NASM, or writing inline assembly with your visual studio programs.
Also: This question is a little too broad for this site.
Comment: I already intermeddate and basic asm but i don't program in in it
Answer: There is a bunch of python libraries that can aid you in exercising exploitation:

Peda - Python Exploit Development Assistance for GDB

Peda has this nice option for generating exploit skeletons. Everything is already set up for you for making a basic exploit, either local or remote. And it serves as a rather nice gdb extension.

Blasty's moneyshot is also a set of rather useful utilities.

A collection of python scripts to aid you in the final steps of binary exploitation or during the construction of buffers.

Hellman's libformatstr is a nice format string automation exploitation library and it already comes embedded in previous two.

Also, if all you really need is packing/manipulating binary data, python's struct library is a must.
There's also Pyhton Arsenal For RE list of libraries covering many more useful libraries.
Comment: Thanks guys for libaries really made life easier for me when pwning binarys
Answer: I've been using pydbg for the last 2+ years to great success. Its used by various popular fuzzing suites such as Sulley, PaiMei, etc.
Also, the capstone disassembly framework is highly suggested, especially the op_access functionality as it helps with taint analysis. Keep in mind the application binary interface (ABI) of the platform you're developing exploits on. If its x86/x64, remember certain instructions will flag different unecessary registers as read/written to.
As an example,
rep movs*

Is used by various functions, especially on WindowsXP+.
The capstone disassembly framework will state that ecx, edi and esi are ALL read and written to, which means you'll have to write logic to deduce if certain instructions like the aforementioned ACTUALLY read/write to registers. Obviously, ESI and ECX aren't written to in that instruction. Usually compilers will specify the number of bytes to read in the previous insruction, e.g.
mov ecx, 0x##

However, for ~80% of instructions it will give accurate information (EFLAGS not withstanding).
It should take a few days or a week depending on free time to write logic to determine if a register is actually accessed.
I'm only assuming the basic instruction set is what you need, not FPU, SIMD, SSE, etc. If you RE malware, packed or optimized binaries, you will need to add logic for the aforementioned and more instruction sets

Exploit Development with python


Should we allow question about the developers?

Question: Should we allow question about the developers?
Where do we draw the line?
Comment: Fine line though. The question "Who wrote the Linux kernel?" can be found on the Linux site. The answer includes info about Linus, that he was a student and that he started writing it because he was unhappy with the current ones. "Who is Satoshi?", "He is the one who wrote the Bitcoin paper and implemented the first versions of the Bitcoin client. His name is a pseudonym". That's pretty much the same thing. But I agree that we shouldn't start digging into people's personal lifes.
Comment: @Dori Could you elaborate what the advantages of disallowing bitcoin developer related questions are? I'd really like to hear some arguments from the other side.
Answer: In my opinion, a security relevant and trust demanding software like bitcoin, justifies  that questions about the developers are allowed.. So I'm in favor to allow questions about the developers, if they

don't provoke an debate, have an clear answer
are related to the development somehow
don't get to personal
Answer: I certainly agree that questions about the devs should be allowed, but only to a point. If someone really wants to don the tinfoil hat that is their prerogative, provided they do their own research somewhere other than this site.
The question you cited in your question was closed not because it is irrelevant or because questions about the devs shouldn't/can't be asked but because it was a duplicate. Perhaps not an exact duplicate, but this specific question is a subset of another question requestiong Satoshi's bio. This question should have been posed in the comments on the original.
Per Robert Cartaino (one of our SE-supplied mods, until we elect our own):

It's off topic. This site is about Bitcoin. It doens't need to become fodder for Who-is-Satoshi-Nakamoto trivia. Any biographical information you feel the need to expound on can easily be contained in the other thread. No need to perpetuate this this content of dubious value through the site.
Comment: The problem is that we won't have a *few* Satoshi questions. When you have a "mysterious figure" like this involved in anything so potentially disruptive as Bitcoin, we are going to get a constant influx of Satoshi questions. If we consider "Is Satoshi involved with CIA" to be different than "Is Satoshi involed with FBI" (which it technically is) this will quickly cease to be bitcoin.stackexchange.com and become satoshi.stackexchange.com. We MUST have stronger moderation than the forums. No tinfoil hats, no politics, no chitchat.
Comment: How is "Is Satoshi involved with the CIA" any better or worse than "Are Bitcoins poisonous"? They're both stupid questions, but it's because they're asking if made up nonsense is true, not because questions about Satoshi Nakamoto are off-topic.
Comment: If only there were a "this question is stupid" option to close. Would that qualify better as "not a question" or "not constructive"?
Comment: I get your point. But **how can something be off topic if it's allowed in another question?** So the question would be, do we wan't to merge everything, for example, satoshi related in one big question? I don't see how having a few separate questions about satoshi around is any worse than having one big one. In fact, I think it's the better and clear solution.
Answer: Questions about the developers are some of the most frequently asked when I talk about Bitcoin. Closing threads of this nature only prolongs the amount of time it takes for people to find answers...
It's counter-productive to obscure this information when it is one of the most commonly asked questions!
Comment: Yes. The crappy part about that question was the CIA speculation, but that has been removed. Let's reopen it.
Answer: Flow is right.  Bitcoin is highly dependent on the skills and ethics of the developers.  Questions that are otherwise on topic but also relate to people like developers who have significant influence over bitcoin should not be arbitrarily ruled out.  Linus arguably has less influence over the Linux kernel than some of the bitcoin committers do over bitcoin, since only a small percentage of Linux users directly run the actual "mainline kernel".
But of course we should be careful about how such questions are worded.
Comment: one hopes that changes as bitcoin grows though. Linus certainly had a lot of control over the kernal when he was the primary developer.
Answer: Re: David's recent question - https://bitcoin.stackexchange.com/questions/1274/is-this-google-account-the-real-satoshi-nakamoto - I voted to close, I think this is getting a little close to speculation and irrelevance. Especially when it is clearly just a troll account.
Comment: This is a good example of a question that is clearly off-topic, because it is very unlikely to be answered with comprehensible facts. But other questions about satoshi, for example [mine](http://bitcoin.stackexchange.com/questions/314/what-was-the-last-life-sign-of-satoshi-nakamoto), **where the answers can be backed by references, links etc. should be on-topic**


Monitor speakers and distance from the walls

Question: I got some monitor speakers for my studio (Yamaha HS8), but they seems to sound better if I keep them 4 or 5 feet from the walls. When I move them near the walls they don't sound equally good. Does anyone know why this happens?
Answer: "Most people have noticed that when a speaker of any size is placed against a wall, it'll deliver stronger bass response. This can be a strong temptation to use this acoustic phenomenon (a function of standing waves) to provide some additional heft, especially from smaller (less than 8") woofers. But this room-enhanced bass will have an uneven frequency balance, and can trip you up when making critical decisions about low-end EQ, and the balance of key mix elements like kick drum and bass guitar. Many, if not most, monitors are designed to deliver the smoothest low-end response when placed at least a foot or two from the nearest room boundary (wall, floor, or ceiling), and while this free-standing placement, without reinforcement from room boundaries, won't deliver as much thump, the bass that is present will be a more correct indication of the low-frequency energy that's actually present in the recording, which is extremely important. One of the most common flaws of small- or home-studio mixes is either too much or too little low end, or uneven bass, caused by EQing to compensate for irregularities that are unique only to the room and monitors in use during mixing." Source: link
Comment: Correct, and the worst thing about resonances (in my opinion of course) is not the bass boost, which most often does not correspond to the low energy in the mix, but the fact that they ring for quite some time... This can make the sound muddy, covering a big part of the mix (due to other psychoacoustical reasons too) and the impulse response of the listening spot spread out quite drastically in the low end.
Answer: That's caused by reflections off the walls interfering with the direct sound from the speaker. At some frequencies, the reflection will cancel out the direct sound, at other frequencies they will add up, so the frequency response changes from the intended one.
The manual may contain some information on the intended placement of the speakers.
Some speakers are designed to take advantage of this (e.g. bookshelf speakers), again this will be stated in the manual.
Comment: In addition to this excellent answer, if moving the speakers closer to the walls is desired (ex: for layout or aesthetic purposes), absorption could be added to the walls (like acoustic panels) to minimize the reflections
Answer: One of the best resources that deals with this subject is to be found on the site of Genelec, speaker manufacturer.
https://www.genelec.com/sites/default/files/media/Studio%20monitors/Catalogues/monitor_setup_guide_2017.pdf
Specifically, page 9 of this document is worth a read.
Answer: The reason, as already explained, is resonance - standing waves that form when you are in proximity to a wall.
Note this also applies to all other walls in the room, not just the one the speakers are against.
If you are working in a space where you can't really do much to alter the space itself, then sometimes you can get a free ride by playing with the angles.
I discovered this almost by accident at home, after having worked for many years in a 'real' studio that was designed with the desk in a 'flying V' shape, which I wanted to recreate at home.
The only way to do it in a more confined space was to turn my work area into the corner rather than against the flat of a wall. This allowed me to arrange keyboards & ancillary equipment in easy reach, left & right.
Here follows the worst piece of CAD ever made ;) showing how I achieved my almost accidental setup - which I've had tested & comes out remarkably flat, considering.
The speakers are elevated, so I have work room below, inc computer monitor etc. Not really to scale & the work area doesn't convey how well it works in practice, I had enough difficulty getting it this 'pretty'. It's really very ergonomically sound. The grey squares are the speakers, I couldn't persuade them to line up any better… good job I never wanted to be an architect.


Retention on workflow history list not working

Question: I have a workflow history list that is large so I have gone into information Management policies and set a LIST based retention schedule with a stage that deletes items that are 1 day greater than the 'Created' Date:
(Created + 1 days Permanently Delete (Recurrence = No).
Something is obviously not working because the workflow history list is growing and nothing has been deleted. I Googled the issue and found the following StackExchange link which educated me a little on the back end mechanics. I checked the jobs for expiration policy and Information management policy were working i.e. no errors and also ran them both and then set them both to daily but the list is still growing. Any ideas?
Pictures:
Comment: That should take care of it, we made those alterations in our farm to run daily and have not seen any problems. Make sure the information management policy runs before the expiration job and that you configured them for the right web application (there are jobs for each web app).
Comment: I just manually ran the IMPolicy and then the ExpPolicy in that order and the list has still had no deletions occur on it. Is there something I/m doing wrong in regards to configuring the list information policy at the list level. For instance I'm not sure what it means by records and non-records!?
Comment: Can you include a picture of the configuration?
Answer: Those configurations look to be correct so long as the IMPolicy timer job runs before the ExpPolicy timer job. This then leads me to believe it is something with the policy you are not configuring correctly.
Here is an example config on a library I have to delete documents that are over 45 days old. This has been working flawlessly without issue since creation. In your scenario, you could change it to Permenantly Delete.

EDIT: I believe thi s is because you have set the retention policy on records so when the timer jobs run nothing happens, unless you mark those entries as records. You want to use the upper block, the non-records section configured like you have it and you should see the items get deleted.
Comment: There is a little picture icon in the toolbar of the text editor that will allow you to upload pictures.
Comment: Updated answer, it is because you have it configured on Records, not the non-records section.
Comment: How do I upload photo's??
Comment: I have noticed under the Job History that when the IMP runs it appears to take 20 seconds and succeeds but then there are another 8 entries that take 00:00 duration and still labelled as succeeding!?
Comment: Pictures added...didn't realise I had to 'EDIT' original post. Thanks
Comment: GREAT...just went from 55k to 5k, I'll mark this as answer - 1 more question: If I template this site or list will the retention policy be included?
Comment: It should, but I can't confirm it


Tor connection in guest OS is being blocked by unknown firewall At Host OS part 2

Question: a few days ago i have posted this:
I am having a problem setting up tor through virtual box and let me give you guys some details: I have installed tor bundle on win xp that is installed on virtual box but when i am trying to activate tor bundle it won't connect, it will get stuck in the "loading network status" level. I have malware anti bytes installed on the pc and norton anti virus. malware antybytes will show me message when i am trying to connect to tor like :"website blocked ip:61231 port" i will get a few messages like this and it just won't connect to tor on guest os. i tried to deactivate norton and malware antybytes but it still won't connect to tor. What else shall i try?
and i have gotten this answer from Alexey Vesnin:
Malwarebytes is blocking Tor - it's a known issue. If I got you right - you have two antiviruses on one PC, it's a bad idea nowdays: I remember 1994 - yes, then it made some sense, but not now. Some network filtering is remaining when the AV is deactivated, and - if your host is also Windows - it can activate windows defender+firewall when disabling other antivirus... Use network bridge for your virtual machine - it should keep you out of trouble. And feel free to ask further if it will not work - together we will solve this, don't worry!
I didn't know if i should respond over there in the answer section or i should just open a new question tab, so that is what i am doing.
So, i have removed malware bytes from my pc and i have stayed just with norton, but still i am not able to connect to tor through the guest os.
n.b what exactly and how exactly do i do the network bridge that you told me?
because when i am trying to bridge the virtual box network adapter it tells me that i can bridge it just to another lan network and my main network is wireless.
please help me.
Answer: You need to make a bridge to the adapter you're using to talk to your LAN. For a wireless adapter there's no problem at all in VirtualBox - take a look at my screenshot:
Add your screenshot, OS version and details if you can't see your wifi adapter for a bridge


Prevent Gmail from delivering emails of a thread to the inbox once a label is applied to it

Question: I have a lot of emails to which I apply labels and remove it from the Inbox. However, when a new email in the thread arrives, it again comes to my Inbox (and is also in that label's folder). How do I prevent it from coming it to the inbox? Please note that many a times, there are no specific rules for these (when I do give rules however, I say skip the inbox but otherwise, how to do?)
Comment: I was hoping a filter of "Matches: has:userlabels; Do this: Skip Inbox" would work, but it doesn't. (Labels are actually attached to individual messages, not conversations.) I don't think you can do this natively in Gmail.
Answer: You can use Gmail's Muting feature to automatically have subsequent messages bypass the inbox, but that won't automatically apply the label.  For that, you would need to create a filter action based on the subject line.


Overheated while driving now it won't start

Question: When I opened the hood I saw the radiator cap missing now car won't start...why won't it start
Comment: have you searched other questions on this stack? Such as https://mechanics.stackexchange.com/questions/46628/drove-with-radiator-cap-not-tight-all-theway which would have told you to give the make / model 7 year so people may be able to help???
Comment: Possible duplicate of [Mazda 323: Plugged in Coolant Temp Sensor - Now Car won't Start](https://mechanics.stackexchange.com/questions/12788/mazda-323-plugged-in-coolant-temp-sensor-now-car-wont-start)
Comment: More than likely you blew the head gasket, Does the engine sound like it has compression? You might want to refill the system and pull a spark plug or two and see if it's leaking into the cylinder.
Comment: Most likely the cylinder head warped. Depending on how long the engine was driven without coolant, the repair could be just a head job to a completely new engine.
Answer: UGH, not good.
How long were you driving before you noticed the missing cap, it must have been overheating?????
Probably some nasty damage to the engine.
You can do a very simple evaluation for engine damage. Disconnect battery then put a socket and ratchet on the crank-bolt and turn the ratchet clockwise......it should move with some effort and eventually get harder to turn as the valve close. If it does not turn or turns very easily, this is an indicator of something wrong with the engine.
Answer: We replaced an engine in a chevy astrovan about ten years ago.  I checked her water and there wasn't any at all in the engine.  I asked her "was it leaking" and she said "yes but it stopped".  Obviously it stopped.  It was out of water.  In her case the block was cracked requiring an engine replacement.  It's possible it may start when you add water.  If you don't need to add maybe two gallons, then it was merely low.  The reason head gaskets blow in this situation is they are softened in heat and lose their ability to hold back compression so if you overheat the engine they can let loose in many different ways.  You could get exhaust into the radiator or coolant out of the exhaust.  that MAY be all you did if you even did that, because the bottom of the engine is kept cool for a while with oil.  If that gets overheated, you'll no longer be driving the car because the engine seizes when it's overheated to the point the oil is burning dry.  I have experienced this and so has my wife.  I was driving an 82 Caddy and the check engine light was in the center of the dash where sunlight could hit it so i didn't see it on.  Bottom radiator hose went.  My clue was the car slowing down. When it cooled off i was able to drive it, but the heads were destroyed.  It would blow all of the water out of the radiator within a mile.


Acrosomal enzymes and the female reproductive tract

Question: My textbook wrote that the reason why acrosomal enzymes are so securely contained within the sperm (thus needing capacitation to facilitate their release) is to prevent any premature release in the male reproductive tract. If they were released, they would start digesting the male organs. However, wouldn't this apply in the female reproductive tract too, once capacitation has occurred? Does the female reproductive tract have some sort of protection against this? (I'm assuming that the sperm has been capacitated but has not fertilized the egg yet.)
Answer: The acrosome reaction does not take place till the sperm reaches the zone pellucida of the ovum, which causes the acrosome to rupture. Thus the female reproductive tract does not get exposed to the enzymes.
Links:
https://en.wikipedia.org/wiki/Acrosome_reaction


Social community management software recommendations

Question: I've got a client with several WordPress hosted websites. Recently, I have been talking to them and they told me their long term idea of their work.
In future, they want to build a community of like minded people that can potentially have thousands of users. Now they have shown me what they have in mind particularly. They want a Facebook like social network with being able to make groups that people can join, posts statuses and have a hashtag tagging and filtering. For example, when someone posts a job opportunity with a #JobOpportunityItaly or #Italy so when you click on #Italy to get a filtered search with job opportunities, announcements and every post with hashtag #Italy.
They have sent me the link to one similar social network and it is Impact Hub.
It is subscription based network which has all the features which I specified above.
They also want it to be hosted by them and they want to build a social network of like minded people and it can potentially have thousands of people using their network. It would be based on a monthly subscription as well.
They want a long term solution so they don't want anything like a forum or a WordPress plugins like BuddyPress or similar.
What I need are recommendations for social network system solutions either paid or free community editions, free systems, etc.
Also, should I go with a custom solution built completely custom or upon an MVC framework or any other ideas. I'm open for all recommendations.
Answer: Although this question was asked three years ago, here's a few platforms we've come to appreciate over the years:

Workplace by Facebook - Facebook's entrant to the market
Discourse - for "civilised discussions"
Jive - enterprise player, been around for a while
Vanilla Forums - "forums reinvented"
Higher Logic - open source platform
Lithium - growing, acquired Jive-x


Toasting bagel in my oven

Question: How much energy am I wasting by toasting my bagel in my big oven? Should I get a toaster?
Comment: Are these frozen bagels, or (reasonably) fresh?  If fresh and/or day old, you can heat up a cast iron pan, and then set the cut side down on it, and wait a minute or so.  It also has the advantage that it doesn't heat the outside so much that you can't hold it.
Comment: They arn't fozen, but they are refrigerated. Neat idea, but I don't like the insides of my bagels toasted, just the outsides.
Comment: Are you using a broiler in the oven, or are you preheating the whole oven just for toasting?  Putting a bagel under a broiler for a quick toast will probably waste more energy than a toaster, but it's still just heating one element for a relatively short time. If you're heating a big oven several hundred degrees just to toast a bagel, obviously that's going to waste a lot more energy.
Comment: I am preheating the entire oven. I don't know what broiling is. I vaguely remember seeing it on my oven, I'll take a look when i go home.
Answer: A toaster is more efficient than a toaster oven, which in turn is far more efficient than heating an entire conventional oven.
Toaster statistics:
Approximate time to make toast – 4 minutes
Watt measured while running – 820 W
Resulting electricity usage – 0.055 kWh
vs
Toaster oven statistics:
Approximate time to make toast – 5 minutes
Watt measured while running – 1110 W
Resulting kWh usage – 0.093
Lower kWh usage means the toaster is more efficient than a toaster oven.
Here is the source for the comparison of toaster vs toaster oven.
Now, you can compare the less efficient toaster oven to a conventional oven here (or to a microwave, but you don't really use that for toast). Toaster ovens use about 1/3 to 1/2 the energy of a conventional oven. So if a toaster uses less than a toaster oven, and a toaster oven uses far less than an oven, then clearly a toaster would be far less wasteful than the oven.
So YES, buy a toaster!

Toasting bagel in my oven


I want to understand the science of sound.

Question: I'm interested in digging deep into the science of sound and I was wondering if there are any must-read resources that anyone could point me to. I understand that this is a broad topic, so I am prepared to read a lot. Thanks!
Comment: Try google! i didn't read a book but i read probably 400 science articles related to different sound concepts and also i studied oscilloscopes in reaktor3 and decomposed synthesizers for many hours. for synths, The "Synth Secrets" series from Sound-On-Sound describe drums (chaotic waves that form noise on a drumskin) gongs(a random distribution of perfect sine waves) strings(sawtooth waves) flutes, filters etc etc. Reaktor is a good learning environment because you can simply hook up classic components of sound generators like filters additions multplications and see and listen to what it does
Answer: This is a very interesting read.
http://www.physicsclassroom.com/class/sound/
http://en.wikipedia.org/wiki/Sound
That should keep you busy for a short while.
Answer: Sound For Film and Television by Tomlinson Holman goes quite extensively into the physics, psychoacoustics and practical applications of sound as related to the production and post production film industry. It's a good textbook to read and have as a reference.
Comment: Im reading all the time as a reference, its a fantastic resource. Recommend!
Answer: the 'science of sound' of sound is an incredible wide area. I'll recommend some books too, but first I think you need to clarify what you will do. If you start thinking about a career in the audio-business, I'd recommend to you to get an overview what you're interested in. Because you have posted here, you probably are interested in filmsound and also this field is a wide area by itself: -Location Sound -Post Production Sound -Sound Editing -Sound Design -Foley -ADR -Music Recording -Music Programming -Studio Desiging -Acoustic Engineer and so on.
I'd recommend to all folks who are interesting in this jobs to go out and have a look. Call the guys in your environment and ask them if you can work as a trainee for some days. I'd recommend to ask a location sound engineer, if you can come to the set. Everything you see in real, helps you can decide if you really want to do it for a longer time. Filmmaking as a sound editor is not always having fun in recording some fancy stuff, it also means to sit alone for weeks in front of a computer, chopping sounds. Find out, if you like/can do that or not.
For film sound I'd really recommend you this books: 'Audio in Media' by Stanley R. Alten: This is your book! it shows the principles of sound, like 'what is a sound', 'what is a sine', 'how does we hear', also it goes into music theory, acousitic, live sounds, orchestra sounds, film sounds, studio design, microphones, signal flow and a lot more.
'Sound on film' by Vincent Lobrutto: Great book with 25 interviews with creators of film sound like Walter Murch, Jim Webb, Frank Serafine, Gary Rydstorm and more Also check the other books from Lobrutto.
'Principles of Digital Audio' it's a hard peace! If you have understand it, you can give us some lesions in digital converting and how it works.
I hope this helps for the moment. One important thing is: LEARN TO LISTEN! If you're in business with sound, you need to have an exact imagination how something should sound. For example, a rock-drumset sounds different than other styles. This seems obvious, but if I ask you, what the difference is, would you know it? As a specialist for sounds, you're not listening music anymore, you're listening to a mix of single elements: bass drum, snare, hat, toms, percussions, guitar, bass guitar, effects, reverb and so on. Same for film: backgrounds, foregrounds, foleys, effects, voices, music, atmospheres.... an how it's prepares. It's difficult to explain in english, but I hope you know what I mean.
best
Guido
Answer: Look through Synth School's videos, there are some excellent explanations on how sound works.
http://www.youtube.com/watch?list=PL0CF041F562C5BE5E&v=YsZKvLnf7wU
Answer: Pure physics and mathematics textbooks/resources.
I find it very hard to approach the fundamental topic of "science of sound" from any other direction.
Answer: I find a good understanding of acoustic principles a vital aspect for sound design.  I recommend Master Handbook of Acoustics to my students. Quit scientific, but gives some great descriptions of the principles.
Answer: If you are interested in more Synthesis techniques (which have quite a bit of physics and acoustic principles).  There are a few "bibles":
The Computer Music Tutorial by Curtis Roads
also:
The CSound Book and by Richard Boulanger (focusing on using c-sound, but the fundamentals can be applied to any synthesis technique, I studied with Dr. B and this book is a collection of essays on different techniques of synthesis, DSP, etc from some of the pioneers of digital audio)
Then for Audio in general (especially digital):
Mastering Audio by Bob Katz is a must
Good Luck!!!


How does the Mac choose which connection to use when both Wifi and Ethernet are connected?

Question: When I'm connected to two networks with separate routers using Wifi and Ethernet, how does my Mac know what connection to use when I visit a website?
Answer: From the Apple Support database article regarding network connection priority:

If you connect to the Internet or a network in several different ways
  (using Wi-Fi or Ethernet, for example), you can change the order of
  the network port configurations your computer tries when connecting to
  the Internet or network.
If there are multiple active network port configurations when you try
  to connect, OS X tries the one at the top of the list first, and then
  tries the other port configurations in descending order.

In that support article it is also described how you can change the priority order of network connections in System Preferences.
Comment: If ethernet is higher priority but disabled & Wifi is enabled & connected, what will happen when I plug in to ethernet? Will I disconnect from the network & reconnect? Or stay connected via Wifi?
Comment: This doesn't explain how a user can know **which** interface is **now** used for outgoing trafic, when several interfaces are actives and connected.
Comment: Is ther eany way to route all ssh traffic over wifi and rest over en0 (LAN)?
Comment: → anotherdave: the Wi-Fi interface will be turned down
(equivalent of an `ifconfig en1 down`), and the Ethernet interface will be turned up (equivalent of an `ifconfig en0 up`). If this last one is based on DHCP, this will cause a DHCP request and answer (< 6 s).
If any of your interfaces have intermitent drop out, this will lead to an endless interfaces switching and DHCP requests.
Comment: Just note. Since Apple engineers are stupid as, you can only use one interface at a time. And you need to order the one on top you want to use. If you try to access an IP that is not on the top most interface it simply will not work.
Comment: @JulianF.Weinert could you back this up? I do this regularly.
Comment: this is a good thread. if you are connected via Wifi only and then connect a wired( eg thunderbolt to ethernet adapter) and the thunderbolt connection has priority, how does macOS react? Does it switch existing connections to the higher priority connection? does it leave existing where they are and only new ones are on the new connection? this is the real question.
Answer: It's in your Network Preferences. Here's screen shots from 10.7.3.
Access the settings from the gear at the bottom of the network type sidebar.

Choose "Set Service Order..." to drag them into the preferred order.
Comment: This doesn't explain how a user can know **which** interface is **now** used for outgoing trafic, when several interfaces are actives and connected. With such a configuration the **Wi-Fi** icon in the menu bar may be full black when in fact all your network activity is going through the **Ethernet**! Such a configuration may create a network loop no user will ever be able to see and debug.
Comment: @danielAzuelos Sure, but that's not the question here. It's about how the Mac chooses, which is a priority based system. If the one on top is working, you're connected. In the main network panel, you can see what interfaces are connected and whether or not it's a successful connection. Cross-ref that with your priority list and you *should* have your answer.
Comment: @plainclothes what if you connect / disconnect network interfaces? how does macOS behave? say I'm on wifi and then connect ethernet so now I have both. What happens with existing and now connections? what if I do the opposite? how does priority play into all of  this?
Answer: I recommand you to never use a configuration where you may have at the same
time different interfaces up on the same machine. You won't have any easy knowledge and control of this dual connectivity.
This may lead to huge difficulties to analyse even the simplest network trouble.
This may also cause loops within company or personnal networks very hard to diagnose. For example, have a look at the following command:
sysctl -a | grep forwarding

which will show you if IPv4 or IPv6 is going through your Mac from one
interface through the other without your knowledge or control.
As much as possible define locations with the interface you know you want to
connect to and switch on the right one at will:
Apple menu > Location > Home / AirPort
                      > Office / Ethernet
                      > outside / AirPort [unsecure]
                      > …

When 2 (or more) interfaces (for example Ethernet and Wi-Fi) are flagged green (Connected) within:
Apple menu > System Preferences… > Network

one way to know which one you are taking to reach the outside is the following line command (within a Terminal or xterm window):
route get default | grep interface

Comment: All the answers explain it on a different level. This one is the best because you can see the changes the computer is making when setting the order through the UI like in the screenshots from @plainclothes
Answer: The Service Order doesn't work.  If you test it, you will find that Mac OS prioritizes Wifi over Ethernet, even if Ethernet is set higher in the Service Order.
One way to test it is to measure your bandwidth (e.g., https://www.fast.com) in the following scenarios:

Connected to Wifi, with Ethernet unplugged
Connected to Ethernet, with Wifi turned off
Connected to Wifi and Ethernet

You will find that the speed from #2 is faster than #1 and #3.  You will also find that #1 and #3 are the same speed.
The only solution is to disable WiFi when you connect via Ethernet and turn on Wifi when you disconnect Ethernet.
This script does that automatically!
https://gist.github.com/albertbori/1798d88a93175b9da00b
If you have any issues, search the comments for the error message you encounter.  For example, I got the Path had bad ownership/permissions error, but the solution is posted in the comments.
Comment: 1. wlan connected -> all data through wlan
2. wlan connected + lan connected -> all new data through lan, established connections stay an wlan.
Comment: My test also did not find what was hypothesized (on macOS Sonoma 14.0).

Internet speed was fastest when Ethernet was plugged in, regardless of Wifi connection — 5 to 7 times faster than when only WiFi was connected.

If you want to see the speedtest results: https://imgur.com/a/V9y94Ir
Answer: While this is true for some applications, what I experienced when I had connected my iMac to two ISP's - one wifi and another through LAN - applications like uTorrent and Games could apparently use both networks simultaneously. I got more download speed than individual connections and in case of multiplayer games, I could connect to servers with less lag and latency.
Comment: BitTorrent was built for multiple connections. But most everything else only uses one connection including games. Want proof? Watch your packets and which interfaces they use.
Answer: When my M1 iMac arrives, I will be connecting to my old 2013 27" iMac which I'm keeping until a 32-bit program's conversion to 64-bit is beta.  I could use Wi-Fi or an ethernet cable (My old Mac has Thunderbolt-1).   And I plan on doing some data transferring with my wife's newer iMac with a Thunderbolt-3 cable, carrying my Mac into her Mac's room.
I figure the Thunderbolt-3 is fastest, and Wi-Fi's slowest.
I'm guessing that I should turn off Wi-Fi while I'm doing the transferring, and that's all I will need to do.   Is that correct?
Comment: Hi, you've mistakenly pressed the `Post Your Answer` button, while you have a new question. Please [ask a new question](https://apple.stackexchange.com/questions/ask), describing what issue you have and what you've looked into so far.


How do I get my overachiever to accept her mistakes and live up to her abilities?

Question: My seven year old child is a perfectionist and I believe it holds her back. She is so afraid of making a mistake or "failing" that she is afraid to put herself out there. She is similarly afraid to be the center of attention, thereby, never really trying to win the ball in sporting events, giving it her all in performance-arts related activities, or even meeting her potential academically (she selects really easy books to read, for example). How can I help her realize that mistakes are a part of life and help her realize her full potential?
Comment: Read Carol Dweck's newest book "Mindset" - this issue is a big deal and will effect her as she gets older. Basically, acknowledge her *efforts* but don't label her as "smart"
Comment: A relevant question here seems to be: how do you react when she fails or underperforms?
Comment: Fair question. Truth be told, she so rarely underperforms because she so frequently undertries. But one day she got in trouble in school and I told her I was really proud of her. I was. It was the first time I had ever experienced her allowing herself to be imperfect. Perhaps I'm minimizing my role in this. I've considered that. I do believe that the desire for perfection is baked in her personality and not a result of criticism for underperforming. If anything, I've probably overpraised rather than overcriticized (which I'm learning can also be highly detrimental).
Answer: I think that to a degree this is due to temperament: some kids love to be the center of attention and fool around, and others don't. Related (in my mind anyway) is how willing kids are to try new things and fail. Then there's the question of pride and being worried about being deemed a failure by their peers.
My son has a hard time sticking to things that he is not incredibly interested in or has a natural aptitude for. He'll try something, and if it doesn't go well, he'll get angry, sulky and will not easily try it again - mostly due to the gap between his abilities and where he wants to be. If it's something he doesn't really need to know or be able to do we'll let it go, but if, like reading, it is something important we've been doing the following:

Try and console him, he's not stupid, and it is hard
Give examples of things he did stick with and became great at
Highlight how far he's come already
Explain that he'll never achieve the proficiency he wishes he had if he doesn't keep trying
Highlight some of our own struggles, both past and current, and what we're doing to overcome them
Explain why it's important that he stick with it and the potential future benefits he'll reap
Reward with something he likes if he sticks with it for the next x minutes
Praise his progress whenever we notice it
Ask him to assess how he's doing now compared to the past and if he says he feels he's doing better say things like: "isn't it great that you can do x now?"

This is unfortunately not a one time conversation, but over time, as he has gotten better, they've become less frequent.
Comment: +1 I have had this happen with my son, he tries to do something then complains "it's too hard!".  I tell him to stick with it, and practice and it will eventually work itself out, then point out things he can do that he practiced and does well.  As you note, I've done this over and over again
Answer: I spent three years teaching kids that carry a "gifted" label and a label attached to a variety of learning disorders.  Almost every one of them struggled with perfectionistic tendencies that became disabling at times - it is an innate tendency in some kids.  My husband and I, have needed to be very careful about with our own (currently six-year-old) daughter for the same reasons you list above.  There are a few things parents can do that can worsen the tendency when it already exists, create a tendency toward perfectionism where one did not exist before, OR conversely, help their kids try and fail with grace at least some of the time.
You say your child is a perfectionist and indicate that she is praise averse when you say she doesn't like being the center of attention.  These are both keys in understanding how to help your child (as best you can) learn to move forward. What has worked for us with our little one, and what I have seen work with countless students with perfectionistic tendencies.
Create an Environment Focused on Effort
Make sure that you are focused on her efforts and "journey" as opposed to her accomplishments.  The most obvious way to do this is first to ask the question, "did you do your best?"  If she wins and/or has a great success at something, ask, "did you do your best?"  If she can honestly say she did, celebrate with her.  If she says no, say, "why not?"  Do the same if she fails at something.  "Did you do your best?"  "Yes" - well, lets have your favorite pizza for dinner then."  I've seen this referred to as a "growth" attitude.
Other, less obvious ways to do this include:

Minimize Praise and Critique:

Instead of praising your child for her accomplishments, ask her how she feels about them, "what do you think about your soccer team's win today?"  Likewise, if she has had a failure, "What do you think about what happened today?"  If she answers, "I did my best, but I don't know what happened" she is inviting constructive feedback from you.  If she already knows what went wrong, let her make the appropriate adjustments - or at least lead the conversation
Instead of praising or critiquing your child for something she did, simply notice it non-evaluatively, "I noticed you controlled the ball five times today during the game."  If she feels that was an accomplishment, she'll feel good about your statement.  On the other hand, if she feels she could have done better, she might say, "yeah I know, I held back."  Now you know how SHE feels about it and can respond accordingly.

Praise and Punish only Effort and even use that sparingly.

When critique is required (because sometimes it just is) try to offer her the chance to come up with the alternative.  State what the problem is, "It really bothers me when the house is a mess."  What you need her to do starting with "I,"  "Therefore, I need you to keep the house a little cleaner."  Then, invite her to be part of the solution, "How can we work on this together?"
Make Sure She Has Examples of Success After Failure

Include Stories from Fiction and From History:

"Meet the Robinson's" and its message of "Keep Moving Forward" is a great one.  We also refer to the "Up From the Ashes" song and scene from "Chitty Chitty Bang Bang" which also shows an inventor failing AND succeeding.  How many times did Babe Ruth strike out versus his Home Runs?  Apparently Einstein was horrid in elementary school.  Thomas Edison tried TONS of other options before coming up with just the right filament for the light bulb, or what about Alexander Flemming and his chance discovery of Penicillium?  The example of a quote from Michael Jordon is PERFECT for this.

Include Examples from Your Own Life:

Share your most embarrassing moment with her - couched with something good that came out of it - a lesson learned, a friend made . . .  Do the same with all the failures you've had and can share with her in this light (over time, not one sitting).

Include Examples from her Own Life:

She didn't always know how to use the potty, she couldn't always dress herself/ button buttons etc.  She had to practice first.  Even if you have to dig deep, make sure she knows she has been through this before.
Offer her Chances to Fail in Private
Give her challenges at home YOU know she can handle, but she isn't totally sure about.  Offer a book she is going to think is a little too tough and say, "but I really think you'll like this story.  What if we read it together like in the old days?  You read it to me and if you get stuck you can ask for my help?"  (Totally did this EXACTLY like this with my own daughter to get her to try reading chapter books - NOW Its hard to find books fast enough!)  Then, if something IS a challenge just support her through it.  At the end ask, "Did you do your best? and How did that feel?"
When Failures Occur, Treat them as A Learning Opportunity
Seriously, when she fails at something - celebrate it!  "Woohoo, a chance to learn something - okay what is it, what did you learn, or what did we learn from this one?"  Don't be so over-the top that it feels cheesy or she'll feel patronized, but genuinely empathize with her disappointment, embarrassment, whatever and then say, "But you know, the good news is, I BET there is something to be learned here - that's the way the greatest scientists see it anyway."
Teach and Model Positive Self Talk
Let her see you make mistakes and respond to them the way you wish she would respond to hers: "Oh my gosh! What a mistake I made!  Ah well, everyone does.  I'm going to just keep moving forward" or, "I won't let it get me down" or, "Good thing I know mistakes are often a learning opportunity. what can I learn from this?"
Let her see you try something new and fail: "Oh, singing is So hard - my voice cracked all through my half hour lesson today.  Ah well, I know if I keep practicing, I'll get it"
It will take time, but, overtime, these techniques along with just quality attention and time together will make a difference to her.  She may still struggle with perfectionism.  It might still be hard for her to stand out, but it is a lot less likely to cripple her into doing nothing because of the fear of not doing it perfectly.
Answer: According to one school of child psychology, how you praise your children has an enormous effect on how hard they try. So one possibility is that you should simply praise her for over reaching herself... praise her for choosing a harder book, for example, and don't offer any praise for finishing an easy book. Often times, kids who are told that they are good at something don't want to push themselves and risk not being praised or even being chastised for failure. So it's important not to praise success, but instead to praise effort.
Some further reading on this topic.
Comment: Wow. Great insight and a powerful series on praise. Thanks for sharing it.
Comment: Praise works for adults too, IMO.
Answer: I don't know if it will help, but I like the following quote from the greatest basketball player of all time:

I've missed more than 9000 shots in my career. I've lost almost 300 games. 26 times, I've been trusted to take the game winning shot and missed. I've failed over and over and over again in my life. And that is why I succeed.

-Michael Jordan
Answer: Our youngest daughter is a perfectionist who would only attempt things when she knew she could flawlessly accomplish it. She would have her brothers take her turn at video games and watch what they did. To a large extent, this perfectionism is a large part of her make-up and to try to completely alter it would be like trying to prune a full grown redwood tree into a bonsai pot. We were able to help her imagine what the worst thing that would happen if she tried something she hadn't yet mastered, and asked if she could live with that happening. She has become better and better at recognizing when to extend herself. That was helpful as was being sensitive when to challenge and when to support.
A great video to watch, which is fairly recent, is the Honda video "Failure: the secret to success":  http://www.youtube.com/watch?v=OiaPNlR5A4I
Our family is a theater family of actors. Not surprisingly, our daughter chose to tech, which she did at regional theater, high school, and college. When she was asked to be in a play at college (heavily cajoled by friends), she did what I thought impossible. Without any acting training, she pulled off accent, arc of character, and connection with other actors on stage. She was fantastic. She has since earned a chemistry Phd. As parents we helped form her as she formed herself.
There is really no specific answer, since a parent's response is very situational. You'll know when to challenge your kid for behavior outside their comfort level and when to support.
Comment: It was obviously not clear from the above, sorry. Helping her examine the worst that could happen, and then considering if she could live with that outcome helped again and again. Associated with that was celebrating her successes at risking, unique to her, for our other kids had an easier time taking chances.
Comment: Interesting story. But where's your answer to the question?
Comment: I wish the link wasn't to a "private video."  You had me very interested.  +1 for the idea that examining the worst thing that could happen might help the challenge feel less scary.
Answer: We teach our kids how to play stringed instruments with the Suzuki method, and I think the best parenting book I've ever read was by a Suzuki teacher who's also a child psychologist.
One of the core insights in the book is that with practice, even complex skills become easier. When things are easier, they are more rewarding.
It has been a tremendous challenge to convince our kids in many areas (not just music) that learning things that seem hard and failure-prone (like riding a bike) will happen and they will become easy and fun. But once they get that principle it's awesome. Our littlest is the most gung ho about new things because he's seen his older siblings do it. If yours is an only or oldest child, it's okay if it takes a while.
So the only practical advice I have is that good education proceeds in small steps. Isolate one little skill to challenge her on, and find a way to motivate her to practice until she can succeed. Learning is actually pretty addictive if there's the right mixture of ease and challenge (this is what makes many video games irresistable to some).
Be patient and try to have fun!


At which point do you have the sitemap fully worked out?

Question: Reviewed the project plan for a redesign I'm working on which was put together by a project manager and not informed by a UX'er. The project plan asks for the site map deliverable to be documented first before wireframes. I just wondered if this is actually the case...in the past I've always had a high-level sitemap before I begin wire framing and then after wireframing I create a detailed sitemap? At which point should your site map be worked out?
Answer: Organizations are so hung up on deliverables that it turns a proper UX process into a deliverable process instead.
Which is bad UX.
The ideal is to educate the organization that UX isn't a step in the process with a set of defined deliverables, but rather it is part of the process itself, and the deliverables will change from project to project and even on a defined project, the deliverables will be living documents, not set-in-stone signed-off milestones.
UX is all about guiding the process rather than adding another layer of documentation.
To answer your specific question:

At which point should your site map be worked out?

The answer is, unfortunately: it depends.
In some cases, it's not worked out until after the first release and user feedback starts coming in.
Answer: It's a reality of the Internet that the sitemap for any given site is never "fully worked out"; websites need to be designed from the get-go to be scalable and to adapt to change, especially since most sites nowadays are driven by a CMS that allows people to add new articles and even pages as necessary.
For me the information architecture (IA) is designed as one of the first things after requirements (including personas) are established, since they help provide a skeleton upon which to hang things like wireframes and content inventory from.
It's important, though, to be willing to adjust the IA as requirements change, and to design it from the get-go to be adaptable to new pages being added. Sometimes that means your card sort (or whatever equivalent activity you perform) may not use the exact naming you use on the final website.
Answer: I would speak to your Project Manager and explain that the sitemap is a living document as stated above by DA01.
Site maps change constantly and never sit still, even during the development stage the site map can change, UX is about testing and refining so quite how they expect you to product a sitemap before hand is baffling.
A PM is all about deliverables which is where the arguments usually stem from, try to reason with them, if this doesn't work try and relate it to their job role.  Ask them to provide a list of deadline dates that will not change at all throughout the whole design & development process.  When they turn round and say, "hmmm things change so they the dates may change over time" simply reply with "exactly"
Saying that, there is nothing wrong with creating a high level sitemap at the start of a project, personally I will create a rough sketch of the sitemap as this allows me a basis to work from, I know the key components of whats to be contained within the app; homepage, contact, downloads, blog.  I just build onto these as I go through.


Guidelines for designing usability for Japanese elderly

Question: I'm currently working on a Japanese website (all in Japanese) aimed towards Japanese users age ranging from 50+. It's not a traffic heavy website and it's just mostly text and information with a news/blog.  I know that there are web design/usability features that I could follow for creating a suitable website for the elderly but I worry about designing UI, navs, and in the near future making it responsive. Are there any guidelines I could follow?
Comment: Be aware that Japaneses are way more technophile than westeners. Id disregard any question which isn't Japanese specific.
Comment: I'd be wary of this tendendency to lump everybody "over 50" into one big demographic (50-90) - that would be similar to lumping everyone from 10 - 50 together...
Comment: I'll leave a short comment here about usability for elder people as users. Elder users are less familiarity with the unwritten 'rules' of the web. For example many elder users does not knows how to send message without 'submit' button. Also one elder user asked me why password field is masked and he cannot see the password while typing.
And also elder users does not like to read text with font size less than 12 pixels.
Answer: @robram gave a great talk (video) recently about how he designed the Age UK website. It's ostensibly content strategy, but really ends up being a useful list of how to create online content for older adults. He presents some statistics, such as that over-55s now make up 20% of the online demographic — while these are representative of the UK, not Japan, I feel like they're probably still pretty relevant. Slides of Rob's talk are here.
In general, I'd say go for simplicity. That doesn't mean you shouldn't provide in-depth information (as Rob's talk demonstrates, older adults are much more likely than most to want to read about stuff in-depth) — rather, think about what it's like to be an older adult and how that might affect your designs:

poorer eyesight and duller senses generally — use big clear fonts
poorer, slower dexterity — don't use any fiddly interaction designs that make people chase around the screen, and make sure all click/touch targets are generously sized
less familiarity with the unwritten 'rules' of the web — use well-established design patterns and UI elements, and maybe more traditional navigation styles.
more cautious — make sure you are especially clear in places where older adults might experience anxiety or uncertainty, such as e-checkouts or anything involving money. Make sure users know what to expect, and reassure them with clear language about what just happened when they clicked that thing.
older adults seem to really love iPads — make sure your site works smoothly on touchscreen devices.

I'm sure there's more! Hope this helps you get started.
Comment: Thanks, this is great, most of the things you mentioned have already been accounted for except for the iPad-responsive design for the site. Cheers!
Answer: thanks for Chris for her bigging up of my talk...
Echoing what she said, it's important to make both buttons and fonts big and clear, both for visually-impaired people, as well as those have slight motor control issues, too.
The main thing, though, is to be as simple as possible. Never assume that a design feature is 'well-known' or that a heading's meaning is immediately obvious.
Older people also respond well (as most of us do) to clear visual clues, both images and icons.
And there's also still a sense of mistrust of the web among the older population in general. Too many scare stories in the media (well, in the UK definitely) ... so make it clear why you're collecting personal information if you are doing so.
Overall, though, it's important to remember that older people are really no different to you or I. They just tend to do things a little slower than the younger generation and don't like too much clutter, so the more pared-back your site can be, the better.
In fact, responsive sites will help in this regard, because the reduction of columns as your screen gets smaller, means you're likely to prioritise your important messages and content for mobile.
Does that help?
Comment: Thanks, that's gold! I'll make sure the content-guy ensures no ambiguity within the text to look for more images and icons. Awesome!
Answer: The Nielson-Norman Group has report about designing websites for the elderly, which includes many design guidelines for doing it.  There's more than 100 guidelines in their report, so it's far outside the scope of this answer to include them all here, but here are some things that I've found from this report that are useful:

Elderly users usually have lower manual dexterity, so navigation should be designed to limit the need for fine selection (drop-down boxes, for example, are often problematic).  Make sure that any clickable item has a big click area.
Elderly users usually have less acute eyesight, so select fonts that are easily readable.

The research that I'm aware of is for Western users.  I would love to see research about designing websites for elderly Japanese users and how that differs (if at all) from designing websites for elderly Western users.  This would be a great CHI paper!
Answer: The important thing to understand is that your target demographic is unlikely to be familiar with many concepts that you may take for granted. Look for instance at this site. There's a B I just above this text box. I know without thinking that it is abutton to format text as bold/italic.
This means you need to take fewer shortcuts, and be more verbose in places.
Comment: Thanks, but it's a bit of a vague answer that you put out. For exmaple, regarding navigation: would Japanese elderly use it normally like dropdowns or 'click-downs' (i.e. click a link and a dropdown comes out) and would they be more familiar with a sidebar navigation or a top horizontal bar? And what about 3D vs Flat designs that are found in today's modern website designs. I think a discussion might help better
Comment: True, your question is not a good fit for this Q&A site. Discussions are not the intent here. But to address your example: a large fraction of the elderly struggle even with the concept of navigation itself. You don't really have to "navigate" a book. They can't do F scans of a page.
Comment: Ah, understood. That makes sense since the elderly are used to a more physical media compared to a screen-and-mouse media.
Answer: Perhaps you can clean some insights from this blog on Japanese digital seniors (デジタルシニア) based on some mobile UX. I'd concur with much of what is already said in the answers here such as keeping it simple, larger visuals and affordances, buttons, keyboard as well as mouse navigation, dealing with concerns about clicking contact links, posting comments and so on.
http://debrasoracle.blogspot.ie/2012/11/fujitsu-rakuraku-my-ux-homework.html
We are all temporarily abled by the way, so consider some of these features can have benefits for us all at some point...:)
https://www.microsoft.com/enable/research/phase1.aspx
Answer: Just wanted to add this to the answer pile: screen-reader compatibility and general accessibility.
Along with the usual 'signs of aging', there may be acquired disability and impairment factors to take into consideration too.
Hope this answer isn't too vague. My friend's grandma has cataracts, so relies on her (very loud) screen reader for using the internet (much to his dismay very early in the morning). :)