• Journal of KIISE:Computer Systems and Theory
• /
• v.28 no.12
• /
• pp.685-697
• /
• 2001

Cache memories are small fast memories used to temporarily hold the contents of main memory that are likely to be referenced by processors so as to reduce instruction and data access time. In this paper, we represent analytical models of instruction fetch process for four types of instruction cache structures that can be used for superscalar processors. In the models, we define various kinds of architectural parameters and take cache miss and branch misprediction into consideration. To prove the correctness of the proposed models, we performed extensive simulations and compared the results with the analytical models. Simulation results showed that the proposed model can estimate the instruction fetch rate accurately within 10% error in most cases. Both analytical model and simulation show that the increase of cache misses reduces the instruction fetch rate more severely than that of branch misprediction does. However, the analytical model can explain the causes of performance degradation which cannot be uncovered by the simulation method only. The model is also able to provide exact relationship between cache miss and branch misprediction for instruction fetch analysis.

• The Journal of Korean Association of Computer Education
• /
• v.5 no.2
• /
• pp.39-48
• /
• 2002

It is general that the ICAI(Intelligent Computer Assisted Instruction) consists of 4 modules. Export module, Teacher module, Student module and Interface module. In each module construction, there should be some rules to control strategies efficiently and systematically that are related to the texts and assessment instruments, assessment results and evaluation, feedback, etc. It is necessary to use a method to classify the curriculum into sections with units and to represent the identified relationships between them. These relationships are available to all the process of learning, assessment, evaluation and feedback. In this paper, we propose the method to represent these units and relationships as a graph. In addition, we implement an internet-based courseware authoring tool to support the environment in which several expert can construct concurrently the courseware with cooperation between them.

• International journal of advanced smart convergence
• /
• v.6 no.2
• /
• pp.24-33
• /
• 2017

Since 'teaching coding' or 'programming' classes for computational thinking (CT) education in K-12 are renowned around the world, a pre-service teachers' readiness for integrating CT into their teaching subjects is important due to the fact that CT is considered to be another 'R' from algoRitm for 21st century literacy, in addition to the traditional 3R (Reading, Writhing, and Arithmetic) [2] and CT roles to other disciplines. With this rationale, we designed a guided instruction based CT course for pre-service teachers. We show the effectiveness of the program with respect to the teachers' attitude toward combining CT into their teaching subjects, and mindset changes of learning computing connected with the career development of the teacher themselves. The research focused on the instructional methodology of teaching programing for non-Computer Science Education (CSE) majors who are not familiar with computer science for alleviating the cognitive load of first exposure to programming course under the CT concepts.

• IEIE Transactions on Smart Processing and Computing
• /
• v.4 no.5
• /
• pp.366-370
• /
• 2015

This paper proposes a method for improving a branch predictor for the extendable instruction set computer (EISC) processor. The original EISC branch predictor has several shortcomings: a small branch target buffer, absence of a global history, a one-bit local branch history, and unsupported prediction of branches following LERI, which is a special instruction to extend an immediate value. We adopt a G-share branch predictor and eliminate the existing shortcomings. We verified the new branch predictor on a field-programmable gate array with the Dhrystone benchmark. The newly proposed EISC branch predictor also accomplishes higher branch prediction accuracy than a conventional branch predictor.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2011.11a
• /
• pp.514-516
• /
• 2011

최근 지식 정보화 사회에 있어서 컴퓨터 네트워크 개방화와 함께 컴퓨터 시스템의 보안 위협이 급증하였다. 또한 기본적으로 데이터 보호에 초점을 맞추고 있기 때문에 접근에 대한 제한이 없으며 응용 프로그램에 따라 보안 운영방식이 다르다는 취약점을 가지고 있다. 본 논문은 하드웨어 기반 보안상태 모니터링 가시화를 위하여 TCG에서 제안한 TPM 칩을 기반으로 동작하는 컴퓨팅 환경의 신뢰 상태 및 시스템 자원에 대한 상태 정보를 실시간으로 모니터링하고 분기 추적 모니터링을 통해 논리적 에러의 초기위치를 파악하여 가시화한다.

• Journal of The Korean Association of Information Education
• /
• v.21 no.6
• /
• pp.657-664
• /
• 2017

This study investigates the effect of play-based software education instruction strategy for improving computational thinking as a method of software education. The play-based instruction strategy is a teaching-learning strategy in which the presented code is navigated through play, and the functions are revised and newly reconstructed. We designed an education program with the play-based instruction strategy and applied the program to elementary students. In order to verify the effectiveness of the research, we examined the competence of computing thinking concept and computing thinking practice. As a result, the computing thinking concept and computational thinking practice were that the proposed teaching-learning model is higher than the direct teaching method.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.27 no.7
• /
• pp.1015-1024
• /
• 1990

This paper proposes a program counter unit(PCU) on the pipelined architecture of RISC (Reduced Instruction Set Computer) type high performance processors, PCU is used for supplying instruction addresses to memory units(Instruction Cache) efficiently. A RISC processor's PCU has to compute the instruction address within required intervals continnously. So, using the method of self-generated incrementor, is more efficient than the conventional one's using ALU or private adder. The proposed PCU is designed to have the fast +4(Byte Address) operation incrementor that has no carry propagation delay. Design specifications are taken by analyzing the whole data path operation of target processor's default and exceptional mode instructions. CMOS and wired logic circuit technologic are used in PCU for the fast operation which has small layout area and power dissipation. The schematic capture and logic, timing simulation of proposed PCU are performed on Apollo W/S using Mentor Graphics CAD tooks.

• Journal of the Korea Computer Industry Society
• /
• v.5 no.2
• /
• pp.193-202
• /
• 2004

In this paper, we studied about method that instructor and learner execute teaching-learning activities and about the educational effects of a web based practice instruction. And, in practice instruction, we examined about role and influence of instructor, learner and manager. This study shows the method that instructor and learner execute teaching-learning activities and interaction activities in a "construction of e-business system" curriculum to support the informational education for an industrial workers. The research subject was the 15 industrial workers who enrolled a informational instruction coulee provided for two weeks by kimpo college, As a research method, workers survey, interview, and profile analysis were used for this study. The result of this study show that interaction between instructor, learner and manager was not executed actively, but the manner of lecturing about interest of learner, usage of email, question and answer of bulletin board, online-practice were brought an effect on interaction of learner activities and the educational effects.l effects.

• Journal of Broadcast Engineering
• /
• v.20 no.2
• /
• pp.224-237
• /
• 2015

In this paper, we introduce the fast decoding method with the SIMD (Single Instruction Multiple Data) instructions for HEVC RExt (High Efficiency Video Coding Range Extensions). Several tools of HEVC RExt such as intra prediction, interpolation, inverse-quantization, inverse-transform, and clipping modules can be classified as the proper modules for applying the SIMD instructions. In consideration of bit-depth increasement of RExt, intra prediction, interpolation, inverse-quantization, inverse-transform, and clipping modules are accelerated by SSE (Streaming SIMD Extension) instructions. In addition, we propose effective implementations for interpolation filter, inverse-quantization, and clipping modules by utilizing a set of AVX2 (Advanced Vector eXtension 2) instructions that can use 256 bits register. The evaluation of the proposed methods were performed on the private HEVC RExt decoder developed based on HM 16.0. The experimental results show that the developed RExt decoder reduces 12% average decoding time, compared with the conventional sequential method.

• Journal of The Korean Association of Information Education
• /
• v.19 no.1
• /
• pp.113-126
• /
• 2015

This study intends to investigate the features and the difference between traditional instruction and flipped learning through a comparative analysis of verbal interaction on those learning method. The videos of traditional instruction and flipped learning of 5th graders social class were recorded and transcribed, which were analyzed in Flanders verbal interaction model. The results were as follows: First, the flipped learning is composed of students' learning activity and a teacher's statement properly, while the traditional instruction consists of a teacher's statement mostly. Second, the traditional instruction tends to be directive classes that full of dominant, despotic, restrictive communication of teacher oriented. In contrast, the flipped learning is inclined to be nondirective with integrated, democratic, comprehensive, permissive communication of students oriented. Third, the flipped learning emphasizes students' activities and statement and reduces delivery of knowledge, meanwhile, the traditional instruction stresses delivery of content that the teacher centrally located. Lastly, the type of verbal interaction in traditional instruction is a one-way communication, students responding simply in teacher's lectures and questions. On the other hand, in flipped learning lessons, more interactive communication occurs, teachers complimenting students and accepting their comments.