## 2009-01-20

### Search Compensates for Lack of Knowledge

Problem solving can sometimes be modeled as a search problem i.e. we can restate the problem as looking for the answer in the among all candidate answers. For example, solving a jigsaw puzzle can be restated as "Which among all the possible arrangements of pieces do the pieces fit together to form the picture?". The set of "all possible arrangements of pieces" is our solution space and we need to search that space for the correct arrangement.

Sometimes we don't know how to solve the problem, so we use trial-and-error; we try out a solution at random and see if that solves our problem. Search long enough, try enough number of pieces and you will eventually put together the puzzle. This is what is meant by Search Compensates for Lack of Knowledge.

The converse is also applies: Knowledge Compensates for Lack of Search. If you cannot or don't want to spend most of your time searching, you need to search smarter. Which piece fits this piece? You then only try pieces that might fit. What color is this part of the puzzle? If you know this part of the puzzle is blue, you only try blue pieces.

Restated to apply to a larger domain:

• If you don't have the talent, work harder.
• If there's too much work, work smarter.

## 2009-01-19

### Short Introduction to Sign Language, part 2

Part 1 here

Signing space is a three-dimensional space from about the mid-torso to just above the head, extending forward from the chest to about one-arm length away, and extending about half an arm's length on both sides. During most signs, the hands and arms do not go beyond this space.

Fingerspelling space is a small space just large enough to fit the hand; it is located midway near the chin and shoulder. Note that the fingerspelling space is still located within the signing space. Fingerspelling space is where the hands are used to spell out letters borrowed from a written language.

One or both hands may be used in signing, depending on the sign and the sign language. In the case where two-hands are used where only one hand is moving, the moving hand is called the dominant hand (DH) and the stationary hand is called the non-dominant hand (NDH) or the passive hand. Two-handed signs where both hands move in the same path and use the same handshapes are sometimes called symmetrical signs.

There are no left-handed or right-handed signs, one-handed signs may be performed with either left hand or right hand; and either hand may be used as the dominant hand in two-handed signs. In practice, right-handed people usually use their right hand for one-handed signs, fingerspelling, and as the DH in two-handed signs; and left-handed people usually use their left.

## 2009-01-16

### Short Introduction to Sign Language, part 1

Update: Part 2 here

Sign Language is the natural language of the Deaf. It is a visual language and those who use sign language are called signers. Signers use their hands, shoulders, arms, torso, neck and face to communicate. In spoken languages, the basic unit of sound utterance is called a phonemes. Similarly, the basic unit of sign language are also called phonemes even though they are not based on sound.

The Liddel and Johnson model Sign language has five parameters that describe phonemes:

1. handshape - decribed by which fingers and/or thumb are selected and flexed
2. palm orientation (or just "orientation")- described by where the palm is facing
3. hand location (or just "location") - described by where one or both hands are with respect to the face, shoulders, arms, and torso
4. movement - described by movement of fingers, thumb, hand and arms
5. non-manual signals (NMS) - which includes facial expression and body posture

Initial inventory of Filipino Sign Language (FSL) observed over ninety handshapes, approximately twenty locations, and six orientations. Movement can be grouped generally into two categories: gross arm movement (tracking the path of the hand and arm) and internal movement (changes in hand shape).

Liddell and Johnson further grouped these into segments; a Movement segment (M) and a Hold segment (H). Movement segments are portions of the sign where the hands (and arms) are motion or the hand shape is in transition. Hold segments are portions of the sign where there is no motion or where hand shapes are in steady state. Signs are then composed of one or more segments. For example, HMH means there is a Hold segment followed by a Movement segment followed by a Hold segment.

Segments observed in FSL include H, M, MH, HMH, and MHMH.

## 2009-01-11

### Disclaimer

Any errors and mistakes found here are mine. If I have misunderstood anything, please don't hesitate to point them out.Corrections and updates will be posted as soon as I am able.

Thank you!