公开(公告)号：US20140146810A1

公开(公告)日：2014-05-29

申请号：US14015314

申请日：2013-08-30

Applicant: Electronics and Telecommunications Research Institute

Inventor： Joa Hyoung LEE ,  Jin Kyu CHOI ,  Byung Tae JANG

IPC: H04J3/16

CPC classification number: H04W74/0816

Abstract: The present invention relates to a method and apparatus in which an Automatic Identification System (AIS) accesses a radio channel. The present invention includes selecting a slot on which a packet is to be transmitted on at least one radio channel, temporarily sending a first carrier, notifying other AISs that the selected slot has been selected by the AIS, on the selected slot in transmission mode, and after temporarily sending the first carrier, detecting a second carrier transmitted by another device on the selected slot in reception mode. In accordance with the present invention, the AIS temporarily sends a first carrier, notifying other AISs that a selected slot has been selected by the AIS, on the selected slot prior to the detection of a second carrier, and another AIS accessing the same slot detects the first carrier temporarily transmitted. Accordingly, a collision between channels can be avoided.

Abstract translation: 本发明涉及自动识别系统（AIS）访问无线电信道的方法和装置。 本发明包括：在至少一个无线电信道上选择要在其上发送分组的时隙，临时发送第一载波，在发送模式下，在所选择的时隙上通知由AIS选择的所选时隙的其他AIS， 并且在临时发送第一载波之后，在接收模式下检测由所选择的时隙上的另一设备发送的第二载波。 根据本发明，在检测到第二载波之前，AIS临时发送第一载波，通知其他AIS，AIS选择的时隙已经在所选择的时隙上，另一个访问同一时隙的AIS检测到 第一个载波暂时传输。 因此，可以避免通道之间的碰撞。

公开(公告)号：US20240369439A1

公开(公告)日：2024-11-07

申请号：US18644601

申请日：2024-04-24

Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE

Inventor： Seon Hyeog KIM ,  Su Sik BANG ,  Yoon Mee DOH ,  Soon Hyun KWON ,  Young Mee SHIN ,  Sang Keum LEE ,  Jong Jae LEE ,  Joa Hyoung LEE

IPC: G01M3/24

Abstract: An apparatus for monitoring a fault of a pipe according to an aspect of the present invention includes a processor, and a memory configured to store instructions executed by the processor, wherein the processor generates an ultrasonic guided signal in a pipe through piezoelectric transducers disposed on a circumferential outer surface of the pipe which is a target of which a fault is to be monitored, and monitors a fault of the pipe through signal processing for performing correlation analysis and noise removal on a reflected signal generated by the ultrasonic guided signal being reflected at an arbitrary point of the pipe.

公开(公告)号：US20170254338A1

公开(公告)日：2017-09-07

申请号：US15446666

申请日：2017-03-01

Applicant: Electronics and Telecommunications Research Institute

Inventor： Joa Hyoung LEE

IPC: F04D27/02 ,  F04D29/58 ,  F04D17/10

CPC classification number: F04D27/0215 ,  F04D17/10 ,  F04D17/12 ,  F04D27/0276 ,  F04D29/5826

Abstract: Disclosed is an apparatus and method for surge prevention for a centrifugal compressor. An apparatus for surge prevention for a buffering vessel based centrifugal compressor according to the present invention includes a recycle pipe which connects a suction portion to a discharge portion of the centrifugal compressor, a cooler which cools compressed gas received according to an opening of a recycle valve disposed at the recycle pipe, a buffering vessel which stores the gas cooled by the cooler, and a compressor control unit which determines a surge occurrence condition to control opening and closing of the recycle valve and a buffer valve which is disposed at a rear stage of the buffering vessel.