• The KIPS Transactions:PartA
• /
• v.19A no.3
• /
• pp.139-146
• /
• 2012

In the server cluster environment, one of the ways saving energy is to control server's power according to traffic conditions. This is to determine the ON/OFF state of servers according to energy usage of data center and each server. To do this, we need a way to estimate each server's energy. In this paper, we use a software-based power consumption estimation model because it is more efficient than the hardware model using power meter in terms of energy and cost. The traditional software-based power consumption estimation model has a drawback in that it doesn't know well the computing status of servers because it uses only the idle status field of CPU. Therefore it doesn't estimate consumption power effectively. In this paper, we present a CPU field based power consumption estimation model to estimate more accurate than the two traditional models (CPU/Disk/Memory utilization based power consumption estimation model and CPU idle utilization based power consumption estimation model) by using the various status fields of CPU to get the CPU status of servers and the overall status of system. We performed experiments using 2 PCs and compared the power consumption estimated by the power consumption model (software) with that measured by the power meter (hardware). The experimental results show that the traditional model has about 8-15% average error rate but our proposed model has about 2% average error rate.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.12
• /
• pp.17-24
• /
• 2009

More recently, the Green Computing have become a important issue in all fields of industry. The energy efficiency cannot be over-emphasized. Microprocessor companies such as Intel Corporation design processors with taking both energy efficiency and performance into account. Nevertheless, general computer users typically utilize the CPU overclocking to enhance the application performance. The overclocking is traditionally considered as an evil in terms of the power consumption. In this paper, we present effective CPU overclocking schemes, which raise CPU frequency while keeping current CPU supply voltage for energy reduction and performance improvement. The proposed scheme gain both energy reduction and performance improvement. Evaluation results show that our proposed schemes reduce the processor execution time as much as 17% and total computer system energy as much as 5%, respectively. In addition, our effective CPU overclocking schemes reduce the Energy Delay Product (EDP) as much as 22%, on average.

• International Journal of Computer Science & Network Security
• /
• v.23 no.10
• /
• pp.44-48
• /
• 2023

Augmented Reality (AR) is an emerging technology and a vibrant field, it has become common in application development, especially in smartphone applications (mobile phones). The AR technology has grown increasingly during the past decade in many fields. Therefore, it is necessary to determine the optimal approach to building the final product by evaluating the performance of each of them separately at a specific task. In this work we evaluated overall CPU and RAM performance for several types of Markerless Augmented Reality applications by using a multiple-objects in mobile development. The results obtained are show that the objects with fewer number of vertices performs steady and not oscillating. Object was superior to the rest of the others is sphere, which is performs better values when processed, its values closer to the minimum CPU and RAM usage.

• Smart Media Journal
• /
• v.5 no.4
• /
• pp.69-74
• /
• 2016

Recently, parallel computing using GPGPU(General-Purpose computing on Graphics Processing Units) according to the development of the graphics processing unit is expanding. This can be achieved through the processing speeds faster than traditional computing environments across many fields, including science, medicine, engineering, and analysis. However, in using the GPU technology to implement the a parallel program there are many constraints. In this paper, we port a CPU-based program(Video Quality Measurement Program) to use technology. The program ported to GPU-based show about 1.83 times the execution speed than CPU-based program. We study on the acceleration of the GPU-based program. Also we discuss the technical constraints and problems that occur when you modify the CPU to the GPU-based programs.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.17 no.4
• /
• pp.633-640
• /
• 2022

As service robots are applied to various fields, interest in an image processing processor that can perform an image processing algorithm quickly and accurately suitable for each task is increasing. This paper introduces an image processing processor design method applicable to robots. The proposed processor consists of an AGX board, FPGA board, LiDAR-Vision board, and Backplane board. It enables the operation of CPU, GPU, and FPGA. The proposed method is verified through simulation experiments.

• Proceedings of the Korean Information Science Society Conference
• /
• 2003.04a
• /
• pp.269-271
• /
• 2003

본 논문에서는 타원 곡선 암호의 성능을 향상시키기 위한 효율적인 최적 확장체 연산 알고리즘을 제안한다. 제안하는 알고리즘은 CPU에서 제공되는 정수 곱셈 명령 1회 실행에 두 개의 하위체 연산을 병렬적으로 수행하도록 함으로써 최적 확장체에서의 곱셈, 제곱, 역원 연산의 속도를 향상시킨다.

• Journal of KIISE:Computer Systems and Theory
• /
• v.37 no.1
• /
• pp.35-42
• /
• 2010

Guest operating systems running over the virtual machines share a variety of resources. Since CPU is allocated in a time division manner it consequently leads them to having the unknown physical time. It is not regarded as a serious problem in the server virtualization fields. However, it becomes critical in embedded systems because it prevents guest OS from executing real time tasks when it does not occupy CPU. In this paper we propose a hypercall to register a timer service to notify the timer request related real time. It enables hypervisor to schedule a virtual machine which has real time tasks to execute, and allows guest OS to take CPU on time to support real time. The following experiment shows its implementation on Xen-Arm and para-virtualized Linux. We also analyze the real time performance with response time of test application and frames per second of Mplayer.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.5
• /
• pp.656-662
• /
• 2018

Pattern matching algorithm is widely used in many application fields such as bio-informatics, intrusion detection, etc. Among many string matching algorithms, KMP (Knuth-Morris-Pratt) algorithm is commonly used because of its fast execution time when using large texts. However, the processing speed of KMP algorithm is also limited when the text size increases significantly. In this paper, we propose a high throughput parallel KMP algorithm considering CPU-GPU memory hierarchy based on OpenCL in GPGPU (General Purpose computing on Graphic Processing Unit). We focus on the optimization for the allocation of work-times and work-groups, the local memory copy of the pattern data and the failure table, and the overlapping of the data transfer with the string matching operations. The experimental results show that the execution time of the optimized parallel KMP algorithm is about 3.6 times faster than that of the non-optimized parallel KMP algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.12 no.6
• /
• pp.571-579
• /
• 1987

The integral equations used in electromagnetic fields theory can be used for scattering problems. We can obtain various characteristics of scatterer. Ie, power pattern, scattered field, by finding current distribution on the scatterer. In this paper, current distribution on polygonal cylinder is obtained using integral equations in 2 dimension. For numerical aualysis, the moment method is used with pulse function as a basis function and integral equation is used with extrapolation method, which saves cpu time.

• Journal of the Semiconductor & Display Technology
• /
• v.18 no.3
• /
• pp.140-143
• /
• 2019

The Internet has been expanded constantly and greatly such that we are having vast number of web pages with dynamic changes. Especially, the fast development of wireless communication technology and the wide spread of various smart devices enable information being created at speed and changed anywhere, anytime. In this situation, web crawling, also known as web scraping, which is an organized, automated computer system for systematically navigating web pages residing on the web and for automatically searching and indexing information, has been inevitably used broadly in many fields today. This paper aims to implement a prototype web crawler with Python and to improve the execution speed using threads on multicore CPU. The results of the implementation confirmed the operation with crawling reference web sites and the performance improvement by evaluating the execution speed on the different thread configurations on multicore CPU.