Puzzles from the tropics

نویسندگان

چکیده

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Fair Client Puzzles from the Bitcoin Blockchain

Client puzzles have been proposed as a mechanism for proving legitimate intentions by providing “proofs of work”, which can be applied to discourage malicious usage of resources. A typical problem of puzzle constructions is the difference in expected solving time on different computing platforms. We call puzzles which can be solved independently of client computing resources fair client puzzles...

متن کامل

A venomous visitor from the tropics

CASE PRESENTATION A 54-year-old man presented to the emergency room following a scorpion sting to the right index finger. He had been unloading a shipment of mangoes from South America and noted a small scorpion in the box, which he picked up and then killed after the sting (Figure 1A). Following the envenomation, he experienced acute paresthesia localized to the right arm, up to the elbow. He ...

متن کامل

The Thermodynamic Arrow: Puzzles and Pseudo-puzzles

For more than a century, physics has known of a puzzling conflict between the T-asymmetry of thermodynamic phenomena and the T-symmetry of the underlying microphysics on which these phenomena depend. This paper provides a guide to the current status of this puzzle, distinguishing the central issue from various issues with which it may be confused. It is shown that there are two competing concep...

متن کامل

Assembling puzzles from preassembled blocks.

Assembling large jigsaw puzzles is difficult, and most of us haven’t even seen a 10,000 piece puzzle on sale in a toy store. Such puzzles require an enormous dedication, and most children (not to mention adults) are not willing to put the time and effort into their assembly. Moreover, it is only feasible for multi-feature compositions like “Garden of Pleasures” by Hieronymus Bosch (one of the b...

متن کامل

Search Lessons Learned from Crossword Puzzles Search Lessons Learned from Crossword Puzzles

The construction of a program that generates crossword puzzles is discussed. The aim of this research is to draw conclusions that apply to conjunctive search generally, and the experimental results obtained in the crossword-puzzle domain lead us to the following: (1) Lookahead is extremely important when solving conjunctive queries, (2) Compile-time control of search is far less eeective than i...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Nature

سال: 1990

ISSN: 0028-0836,1476-4687

DOI: 10.1038/346317a0