Electronics and Telecommunications Research Institute

Dacom Corporation

Korea Telecom

Hun Soon Lee

Dong Wook Lee

Kyung Soo Kim

Jee Hwan Ahn

June Hwan Kim

Seong Rag Kim

Myung Joon Kim

Jeong Goo Lee

Jae Soo Yoo

Kyoung Joon Lee

Seok Il Song

Jang Sun Lee

Sung Jun Baik

Byung Yang An

Kyung Jun Lee

Nam Jin Park

Pyung Jung Song

Soon Sung Yang

Jin Soo Lee

Ki Seok Kim

Mi Young Lee

Myung-Joon Kim

Jee-Hwan Ahn

Chang Soo Kim

Seong-Rag Kim

Hong Yeon Kim

Sook-Jin Lee

Cheol-Hye Cho

Don Sung Oh

Dong J Shin

Woo-Goo Park

Sung Jin Hur

Gil Rok Oh

Seok Hee Lee

Chang Soon Kang

Myoung-Jin Kim

Moonyoung Chung

Ki Seon Kim

Kyoung Hyun Park

Mai Hai Thanh

Kwang Hoo Kook

Cheol Hoi Cho

Sung-Moon Shin

Young-Nam Han

Seon-Ho Hwang

Chang-Soon Kang

Go-Whan Jin

Mou-Ho Cho

Jae-Wook Jung

Byung-Shik Kang

Myoung Jin Kim

HyoungGoo Jeon

HoonBok Lee

YangGi Kang

JongRay Na

Disclosed is a training method for the optimization of a traffic signal. The method includes segmenting a large-scale road network into intersection groups each including a plurality of intersections, training a reinforcement learning model by allocating a training agent to each intersection group, performing traffic signal control through the inference of an optimal signal based on the trained reinforcement learning model, evaluating whether the results of the execution of the traffic signal control satisfy a preset goal of learning for traffic signal optimization, and repeatedly training the reinforcement learning model based on the results of the evaluation.

Training method and system for optimization of traffic signal

A merge join method by a merge join system including a database is provided. The merge join system unequally divides data after a current position of a join column participating in merge join in the database into K partitions, K being greater than 2, and compares the first value of each of remaining partitions excluding the first partition from the K partitions with a value to be searched for the merge join, in order to check whether the first value and the value to be searched satisfy a specific condition. Further, the merge join system determines a partition in which the value to be searched is expected to exist based on a comparison result, and applies a k-ary search to the determined partition.

Merge join system and method

Disclosed are a system and a method for address translation for a flash memory device, and particularly, disclosed is a technology that is capable of efficiently performing address translation between a logical address provided to the outside of a flash memory and a physical address of an actual flash memory in managing the flash memory device. The system includes: a flash memory system writing a corresponding data page by allocating a physical address space when there is a request for writing a data page from storage clients, and performing address translation between a physical address and a logical address; and a logical address space formed between the flash memory system and the storage client to provide the logical address.

System and method for efficient address translation of flash memory device

A cache consistency maintenance procedure to select one of a detection-based cache consistency maintenance procedure optimized for record-based locking and an avoidance-based consistency-based maintenance procedure optimized for table and block-based locking. To support the characteristic of DBMS in which table locking and record locking are consistent to access the same table, the two kinds of the consistency maintenance policies for the same block are processed by a single buffer load process and the two kinds of the consistency maintenance policies are consistent with each other to provide better configuration and performance.

Buffer allocation method supporting detection-based and avoidance-based consistency maintenance policies in a shared disk-based multi-database management system

A recovery method for a high-dimensional index structure is disclosed, in which a reinsert operation is employed based on ARIES (algorithm for recovery and isolation exploiting semantics) and a page-oriented redo and a logical undo. Further, a recording medium on which a program for carrying out the above method is recorded is disclosed, the program being readable by a computer. The recovery method for a high-dimensional index structure employing a reinsert operation according to the present invention includes the following steps. At a first step, an entry is inserted into a node, a minimum bounding region is adjusted, an overflow is processed, and a log record is stored. At a second step, the log record thus stored is recovered.

Efficient recovery method for high-dimensional index structure employing reinsert operation

A concurrency control method for searching the high-dimensional index tree of a database is disclosed. The concurrency control includes: a) adding a root node to the queue and acquiring the shared lock for reinsertion node; b) determining whether the queue is empty or not, fetching a node from the queue and assigning the fetched node as a current node if queue is not empty, releasing the shared lock and terminating the search process if queue is empty; c) acquiring the shared latch in the current node, selecting the lower nodes which are within the query range and adding the selected nodes to the queue if current node is not leaf or to the result set if current node is leaf; and d) returning to the step b).

Concurrency control method for high-dimensional index structure using latch and lock

The present invention provides an interference canceling method and the apparatus of a multi-mode subtraction type in asynchronous multipath channels of CDMA system, which cancel the interference based on the received signal power of each user (or path), which make the selected fingers keep participating in the subsequent cancellation processing with new (more cleaned) input signal, which do a scale factor's processing and a clipper's processing to make the tentative bit decision, which can select the proper interference canceling method among various interference canceling method according to the total number of users in service, the hardware speed to implement the present method and the power spread of received signals, which repeat the selected interference canceling process recursively with a stage of hardware, which can reduce the number of stage compared with parallel interference cancellation method of the prior art in case that the interference canceling apparatus is made up multi-stages, which do overlappingly a canceling process of the last bit of the multiple bits for efficient operation in the asynchronous channel, which reduce the interference according to the power sequence of each multipath signal instead of the power sequence of each user signal made up multipath signals for efficient operation in multipath channels with unequal powers, which can increase the performance and capacity of the CDMA system by reducing the interference produced by a multiple access process in CDMA system with the asynchronous multipath channels.

Interference canceling method and apparatus of a multi-mode subtraction type in asynchronous multipath channels of code division multiple access system

A method for sharing an associated control channel in a mobile communication system is disclosed, which comprises the steps of: assigning a physical associated control channel between a mobile station and a base station and assigning a number of logical channels to the associated control channel, in order that a number of users can request communication service simultaneously through the mobile station; setting a logical link identification and a link setting flag not used when the mobile station receives a request for a new call setting, and transmitting a connection setting request to the base station through the physical associated control channel; informing the mobile station that the connecting and setting of logical link identification is completed through the physical associated control channel when the base station receives the connection request from the mobile station; and setting a traffic channel for transmitting user information after completing the connection setting.

Method for sharing an associated control channel of mobile station user in mobile communication system

The present invention relates to a signal modulation apparatus of multicarrier direct sequence spread spectrum communication system. There was a problem that since multiple carrier having different frequencies are modulated by a baseband signal and the results are added to be transmitted, the enveloped variation of transmitted signal is very large. A modulation apparatus of multicarrier direct sequence spread spectrum system is suggested to solve such problems, which can reduce the enveloped variation of transmitted signal by inverting the polarity of baseband signal which modulates one of four carriers in the case when the same baseband signal is used to modulate the multiple carriers and by inverting the plurality of one of two Walsh code pairs having two adjacent indexes by using the characteristics of Walsh function in case when different baseband signals should be used to modulate four carriers.

Modulation apparatus of multicarrier direct sequence spread spectrum communication system

A cellular capacity in a multimedia DS-CDMA system may be maximized by controlling a transmission rate of data calls. In a method for maximizing the cellular capacity, the total interference quantity is controlled by restraining the transmission rates of the respective data calls according to diminution factors of a linear, a parabola and a hyperbola; the transmission rate of the data call is increased in case a traffic load is small; and the transmission rate of the data call is decreased in case the traffic is overloaded, thereby more calls can be received and the number of subscribers having a service of voice and data calls in the CDMA circumstances may be allowed most suitably. In case a call of higher priority is newly received under a state that the data call of a high speed occupies a resource of a system for a long time, the transmission rate of the currently progressing data is controlled to receive the new call. Accordingly, the number of subscribers can be allowed at maximum by controlling the transmission rate of the data call so that more voice and data calls may be received within the CDMA system capacity.

Method for maximizing cellular capacity in muti-media CDMA system

A code synchronization apparatus in a multi-carrier direct sequence spread spectrum communication system and method thereof are disclosed. The purpose of the present invention is to solve the problems that when using the conventional code synchronization apparatus used in a single carrier system, the time necessary for synchronization as well as the complexity of the system are increased. To do this, the present invention discloses a code synchronization apparatus in a multi-carrier direct sequence spread spectrum communication system and method thereof which are capable of obtaining a stabilized code synchronization, using a code synchronization method suitable to the situation to adjust the symbol combining gain and the symbol integration period adaptively to the channel situation.

Code synchronization apparatus of multi-carrier direct sequence spread spectrum communication system

The present invention relates to a method for transmitting and receiving informations of control plane using MAC frame structure in order to transmit user data through associated control channel so that the radio resource formed between a mobile station and a base station can be used efficiently, in the case that the third generation mobile communication system which needs large scale control information necessarily uses out-of-band signal method for providing various services. The method for transmitting and receiving information between mobile station and base station of mobile communication system using an associated channel comprise the steps of receiving information from user plane and control plane, constructing a frame, and transmitting the frame which is pointed out by the plane determined by the corresponding information after analyzing the information (step,); and analyzing the frame after receiving the information through the associated channel and receiving the information using the plane corresponding to the frame (step,).

Method for transmitting and receiving control plane information using medium access control frame structure for transmitting user information through an associated control channel

A system for providing a power-efficient soft handoff in a multicarrier CDMA cellular system includes: a determining device for determining a time point when a user of a mobile station executes a handoff operation from one base station to an adjacent base station thereto, during the user communicates with another system's user through the one base station; a providing device for providing handoff request information inclusive of information of the adjacent base station; a base station control device for commanding the one base station and the adjacent base station to transmit stop of information of the another system's user, with non-assigned carrier and for commanding the adjacent base station to transmit start the information of the another system's user, with assigned carrier, in accordance with the hand off request information received through the one base station by the mobile station's user; a base station transmission device for transmitting the information of the another system's user only with the assigned carrier, in accordance with the assignment of carrier of the base station control device; and a receiving device of the mobile station's user for combining and demodulating received signals having different frequencies from the one base station and the adjacent base station.

Method and system for providing a power-efficient soft handoff in a multicarrier CDMA cellular system

The present invention is to increase the efficiency of the transmission channel between the base stations and to improve the accuracy of the signal in transmitting the traffic information in the circuit communication method or TDM method in comparison with the packet method, and provides the method for speech coding at the Code Division Multiple Access base station which can solve the anticipated problem of the frame sync acquisition between base stations in such case.

Voice coding method at a code division multiple access base station

The call attempts are controlled under the traffic overload of CDMA environment provide a method in which when the message transmitted for a new call attempt is failed in the state of traffic overload, the speech quality and the number of mobile station which are on the line are maintained to the desired level by controlling the retransmitting of the message to the proper level.

Method for controlling call attempt under the traffic overload of CDMA

Growing community of inventors

Daejeon, South Korea

Hun Soon Lee