• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.11
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• pp.3731-3750
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• 2014

This paper considers a wideband cognitive radio network (WCRN) which can simultaneously sense multiple narrowband channels and thus aggregate the detected available channels for transmission and studies the ergodic throughput of the WCRN that operated under: the wideband sensing-based spectrum sharing (WSSS) scheme and the wideband opportunistic spectrum access (WOSA) scheme. In our analysis, besides the average interference power constraint at PU, the average transmit power constraint of SU is also considered for the two schemes and a novel cognitive radio sensing frame that allows data transmission and spectrum sensing at the same time is utilized, and then the maximization throughput problem is solved by developing a gradient projection method. Finally, numerical simulations are presented to verify the performance of the two proposed schemes.

• Proceedings of the KAIS Fall Conference
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• 2003.11a
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• pp.10-15
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• 2003

In computer graphics, most animations of characters have been created using the traditional and often highly labor intensive key-framing technique. Recently, character animation is demanded increasingly automated techniques for animation according to interaction with the user or environment of the user. In this paper, we will propose a new method which can animate characters automatical/y with user interactions. The character's behavior is determined as a result of understanding the emotional condition of the user. Psychology and cognitive AI provide some ideas about how to approach this problem. Our study is based mostly on the theories of Ortony, Clore and Collins, which were designed to be implemented computationally. In our system, we can make 22 emotion types and some more behavior features and we apply to some characters.

• PNF and Movement
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• v.21 no.2
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• pp.193-202
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• 2023

Purpose: We investigated the effects of transcranial stimulation and task-oriented training on upper extremity and cognitive function in chronic stroke patients. Methods: A total of 30 patients were randomly divided into transcranial stimulation and task-oriented training groups (TT) and task-oriented training groups (TO). The TT group performed 30 min 5 times a week for 4 weeks in task-oriented training combined with transcranial direct current stimulation. The TO group performed 30 min 5 times a week for 4 weeks in task-oriented training. To measure upper extremity function, the Jebsen-Taylor Hand Function Test, Manual Function Test, and Cognitive Function Test were performed using the Stroop Test and the Trail Making Test. Results: There was a significant difference (P < 0.05) before and after training in both groups, and the TT group showed significant improvement in both groups. Conclusion: In this study, we confirmed transcranial stimulation and task-oriented training in upper extremity function and cognitive function in patients with chronic strokes.

• Journal of electromagnetic engineering and science
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• v.12 no.1
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• pp.32-36
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• 2012

In this paper, we present a novel algorithm for detecting a bonded channel in a cognitive radio network where channel bonding is allowed for a higher data rate. The envelope detection algorithm is proposed to distinguish the center frequency of the received signal in order to determine whether the signal is transmitted by a primary user occupying a single channel or a secondary user occupying more than two channels when the channel is in use.

• Journal of electromagnetic engineering and science
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• v.12 no.1
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• pp.1-7
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• 2012

In this paper, we investigated the throughput of a cognitive radio network where two primary frequency channels (PCs) are sensed and opportunistically accessed by N secondary users. The sharing sensing member (SSM) protocol is introduced to sense both PCs simultaneously. According to the SSM protocol, N SUs (Secondary User) are divided into two groups, which allows for the simultaneous sensing of two PCs. With a frame structure, after determining whether the PCs are idle or active during a sensing slot, the SUs may use the remaining time to transmit their own data. The throughput of the network is formulated as a convex optimization problem. We then evaluated an iterative algorithm to allocate the optimal sensing time, fusion rule and the number of members in each group. The computer simulation and numerical results show that the proposed optimal allocation improves the throughput of the SU under a misdetection constraint to protect the PCs. If not, its initial date of receipt shall be nullified.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2005.05a
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• pp.192-197
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• 2005

인간이 생각하고 지식이 습득되어지는 방법에 대한 이해는 인지과학자들에게 항상 중요 관심사이다. 학교교육이 전개된 후의 학생들을 대상으로 한 인지과정을 탐구하는 것은 쉽지 않다. 본 논문에 유아기 유아들을 대상으로 과학적인 표상능력을 이용하여 유아의 인지구조를 고찰하였다. 5세 유아 120명을 대상으로 2년간 주변에서 흔히 볼 수 있는 곤충류를 관찰할 수 있도록 한 후, 그림 그리기와 언어 표현 방법을 이용하여 유아들의 인지과정이 탐구되었다. 유아들은 1차, 2차 표상과정을 통해 기존에 갖고있던 사물에 대한 개념에 분명한 변화를 보였다. 본 연구결과는 유아들의 과학지식 형성에 대한 인지과정을 기술하며, 과학적 지식으로 확장될 수 있는 효율적인 지도 방법을 제공한다.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2005.05a
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• pp.9-13
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• 2005

A comprehension-based computational model of pilot action planning called ADAPT is presented to model pilot performance in a flight simulation context. Individual pilots were asked to execute a series of flight maneuvers using a flight simulator, and their eye-scanning, control movements, and flight performance were recorded in a time-synched database. Computational models of each of the 25 individual pilots were constructed, and the individual models simulated execution of the same flight maneuvers performed by human pilots. The time-synched eye-scanning, control movements, and flight performance of individual pilots and their respective models were compared to test ADAPT's predictive validity.

• Korean Management Science Review
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• v.29 no.2
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• pp.65-77
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• 2012

With the explosivley increasing demand in wireless telecommunication service, the shortage of radio spectrum has been worsen. The traditional approach of the current fixed spectrum allocation leads to spectrum underutilization. Recently, CR (Cognitive Radio) technologies are proposed to enhance the spectrum utilization by allocating dynamically radio resources to CR Networks. In this study, we consider a radio resource(power, subcarrier) allocation problem for OFDMA-based CRN in which a base station supports a variety of CUs (CRN Users) while avoiding the radio interference to PRN (Primary Radio Network). The problem is mathematically formulated as a general 0-1 IP problem. The optimal solution method for the IP problem requires an unrealistic execution time due to its complexity. Therefore, we propose an heuristic that gives an approximate solution within a reasonable execution time.

• Korean Journal of Cognitive Science
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• v.6 no.1
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• pp.5-30
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• 1995

Fodor and his followers argue that connectionist model does not have compositional structure,or else it is merely an implementation of a classicist model.'Classical constityency'is used importantly to show connectionist model does not have compositional structure.However,in contrast Fodor and his followers,I maintain that it is possible for connectionist model to have compositional structure without attributing classical constituency to cognitive model,and the very classical consitiuency makes the connectionist model nonimplementational.

• ETRI Journal
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• v.39 no.3
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• pp.345-352
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• 2017

Traffic management is a highly beneficial mechanism for satisfying quality-of-service requirements and overcoming the resource scarcity problems in networks. This paper introduces an optimal connection admission control mechanism to decrease the packet loss ratio and end-to-end delay in cognitive radio sensor networks (CRSNs). This mechanism admits data flows based on the value of information sent by the sensor nodes, the network state, and the estimated required resources of the data flows. The number of required channels of each data flow is estimated using a proposed formula that is inspired by a graph coloring approach. The proposed admission control mechanism is formulated as a semi-Markov decision process and a linear programming problem is derived to obtain the optimal admission control policy for obtaining the maximum reward. Simulation results demonstrate that the proposed mechanism outperforms a recently proposed admission control mechanism in CRSNs.