검색연산자 | 기능 | 검색시 예 |
---|---|---|
() | 우선순위가 가장 높은 연산자 | 예1) (나노 (기계 | machine)) |
공백 | 두 개의 검색어(식)을 모두 포함하고 있는 문서 검색 | 예1) (나노 기계) 예2) 나노 장영실 |
| | 두 개의 검색어(식) 중 하나 이상 포함하고 있는 문서 검색 | 예1) (줄기세포 | 면역) 예2) 줄기세포 | 장영실 |
! | NOT 이후에 있는 검색어가 포함된 문서는 제외 | 예1) (황금 !백금) 예2) !image |
* | 검색어의 *란에 0개 이상의 임의의 문자가 포함된 문서 검색 | 예) semi* |
"" | 따옴표 내의 구문과 완전히 일치하는 문서만 검색 | 예) "Transform and Quantization" |
다음과 같은 기능을 한번의 로그인으로 사용 할 수 있습니다.
NTIS 바로가기국가/구분 | United States(US) Patent 등록 |
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국제특허분류(IPC7판) | G09B-005/00 |
미국특허분류(USC) | 35/8A ; 35/35C ; 179/1H ; 179/1MN |
출원번호 | US-0659649 (1976-02-20) |
우선권정보 | JA-0023205 (1975-02-25) |
발명자 / 주소 |
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출원인 / 주소 |
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인용정보 | 피인용 횟수 : 20 인용 특허 : 1 |
An intercommunication system in a group teaching or training system in which a teacher station and a plurality of student stations are interconnected with a common outgoing line and a common incoming line, and each station includes a transmitter and a receiver, and wherein the teacher station includes a switching circuit for selectively connecting the incoming line to the outgoing line, the transmitter and receiver in each student station are selectively connected through switching circuits to the incoming and outgoing lines, respectively, and the switch...
In an intercommunication system in which a teacher station and a plurality of student stations are interconnected with a common outgoing line and a common incoming line, the improvement wherein said teacher and student stations comprise: a transmitter and a receiver, the transmitter and receiver in said teacher station being respectively connected to said outgoing line and said incoming line; first switching circuit means in said teacher station for selectively connecting said incoming line to said outgoing line; second switching circuit means in each st...