astronomy

Hideki Imai

Hideki Imai is a astronomy topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Hideki Imai rather than just read about it. In short: Hideki Imai (今井秀樹, Imai Hideki; born May 31, 1943, in Shimane Prefecture, Japan) is a Japanese information theorist and cryptographer. His research has included information theory, coding theory, cryptography, and information security.

Key takeaways

Hideki Imai belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Hideki Imai to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Hideki Imai from memory before moving on to harder problems.

Reference excerpt

Hideki Imai (今井秀樹, Imai Hideki; born May 31, 1943, in Shimane Prefecture, Japan) is a Japanese information theorist and cryptographer. His research has included information theory, coding theory, cryptography, and information security. In 1977, together with S. Hirakawa, he proposed a coded multilevel signal modulation scheme using several classes of binary error-correcting codes, whose symbols are combined to set up the transmission signal. This scheme is known as the Imai–Hirakawa code. Imai received B.E., M.E., and Ph.D. degrees in electrical engineering from the University of Tokyo in 1966, 1968, and 1971, respectively. From 1971 to 1992 he was on the faculty of Yokohama National University, and from 1992 to 2006 he was a professor at the Institute of Industrial Science, University of Tokyo. In 2006 he was appointed emeritus professor of the University of Tokyo and professor at Chuo University. He also served as director of the Research Center for Information Security at the National Institute of Advanced Industrial Science and Technology. He became an IEEE Fellow in 1992 for contributions to the theory of coded modulation and two-dimensional codes, and an IACR Fellow in 2007.

References

External links Hideki Imai's page at IIS Hideki Imai's page at RCIS ResearchMap profile

Worked examples

Example 1 — a first encounter with Hideki Imai

Start with the simplest possible case. Write down what Hideki Imai claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Hideki Imai before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Hideki Imai ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Hideki Imai

In research: Hideki Imai appears in astronomy research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Hideki Imai in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Hideki Imai is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1943 births, Academic staff of Yokohama National University, Academic staff of the University of Tokyo, so understanding it makes those chapters shorter.
In everyday life: Look for Hideki Imai outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Hideki Imai in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Hideki Imai means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Hideki Imai out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Hideki Imai in simple terms?

Why does Hideki Imai matter?

Because it connects several astronomy ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Hideki Imai?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Hideki Imai.