• Title/Summary/Keyword: Operations of complex number

Search Result 98, Processing Time 0.027 seconds

Design of Low Complexity and High Throughput Encoder for Structured LDPC Codes (구조적 LDPC 부호의 저복잡도 및 고속 부호화기 설계)

  • Jung, Yong-Min;Jung, Yun-Ho;Kim, Jae-Seok
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.46 no.10
    • /
    • pp.61-69
    • /
    • 2009
  • This paper presents the design results of a low complexity and high throughput LDPC encoder structure. In order to solve the high complexity problem of the LDPC encoder, a simplified matrix-vector multiplier is proposed instead of the conventional complex matrix-vector multiplier. The proposed encoder also adopts a partially parallel structure and performs column-wise operations in matrix-vector multiplication to achieve high throughput. Implementation results show that the proposed architecture reduces the number of logic gates and memory elements by 37.4% and 56.7%, compared with existing five-stage pipelined architecture. The proposed encoder also supports 800Mbps throughput at 40MHz clock frequency which is improved about three times more than the existing architecture.

GPS Accuracy Revision Using RSSI and AoA in Wireless Sensor Network (무선 센서 네트워크에서 RSSI와 AoA를 활용한 GPS 정밀도 향상 방안)

  • Cho, Hae-Min;Kwon, Tae-Wook
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.17 no.5
    • /
    • pp.889-896
    • /
    • 2022
  • Data required in a wireless sensor network environment requires more accurate figures as technology advances and its complexity increases. However, in the case of operating a large number of sensor nodes in a large area, the balance between the power consumed and the data quality that can be acquired accordingly should be considered for that purpose. In particular, in complex, densely populated urban areas or military operations with specific goals, location data requires increasingly detailed and high accuracy over a wide range. In this paper, we propose a method of mounting a Global Positioning System(: GPS) only on some of the sensor nodes deployed in the wireless sensor network and improving the error of GPS location data measured on that sensor node through Angle of Arrival(: AoA) and Received Signal Strength Indicator(: RSSI).

Design and Implementation of a Main-memory Storage System for Real-time Retrievals (실시간 검색을 위한 다중 사용자용 주기억장치 자료저장 시스템 개발)

  • Kwon, Oh-Su;Hong, Dong-Kweon
    • The KIPS Transactions:PartD
    • /
    • v.10D no.2
    • /
    • pp.187-194
    • /
    • 2003
  • Main Memory storage system can increase the performance of the system by assigning enough slack time to real-time transactions. Due to its high response time of main memory devices, main memory resident data management systems have been used for location management of personal mobile clients to cope with urgent location related operations. In this paper we have developed a multi-threaded main memory storage system as a core component of real-time retrieval system to handle a huge amount of readers and writers of main memory resident data. The storage system is implemented as an embedded component which is working with the help of a disk resident database system. It uses multi-threaded executions and utilizes latches for its concurrency control rather than complex locking method. It only saves most recent data on main memory and data synchronization is done only when disk resident database asks for update transactions. The system controls the number of read threads and update threads to guarantee the minimum requirements of real-time retrievals.

Optimal Band Selection Techniques for Hyperspectral Image Pixel Classification using Pooling Operations & PSNR (초분광 이미지 픽셀 분류를 위한 풀링 연산과 PSNR을 이용한 최적 밴드 선택 기법)

  • Chang, Duhyeuk;Jung, Byeonghyeon;Heo, Junyoung
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.21 no.5
    • /
    • pp.141-147
    • /
    • 2021
  • In this paper, in order to improve the utilization of hyperspectral large-capacity data feature information by reducing complex computations by dimension reduction of neural network inputs in embedded systems, the band selection algorithm is applied in each subset. Among feature extraction and feature selection techniques, the feature selection aim to improve the optimal number of bands suitable for datasets, regardless of wavelength range, and the time and performance, more than others algorithms. Through this experiment, although the time required was reduced by 1/3 to 1/9 times compared to the others band selection technique, meaningful results were improved by more than 4% in terms of performance through the K-neighbor classifier. Although it is difficult to utilize real-time hyperspectral data analysis now, it has confirmed the possibility of improvement.

An Efficient Search Space Generation Technique for Optimal Materialized Views Selection in Data Warehouse Environment (데이타 웨어하우스 환경에서 최적 실체뷰 구성을 위한 효율적인 탐색공간 생성 기법)

  • Lee Tae-Hee;Chang Jae-young;Lee Sang-goo
    • Journal of KIISE:Databases
    • /
    • v.31 no.6
    • /
    • pp.585-595
    • /
    • 2004
  • A query processing is a critical issue in data warehouse environment since queries on data warehouses often involve hundreds of complex operations over large volumes of data. Data warehouses therefore build a large number of materialized views to increase the system performance. Which views to materialized is an important factor on the view maintenance cost as well as the query performance. The goal of materialized view selection problem is to select an optimal set of views that minimizes total query response time in addition to the view maintenance cost. In this paper, we present an efficient solution for the materialized view selection problem. Although the optimal selection of materialized views is NP-hard problem, we developed a feasible solution by utilizing the characteristics of relational operators such as join, selection, and grouping.

Feasibility Study on the Duration of Shiwha Techno-Valley through Simulation (시뮬레이션을 이용한 시화 테크노 벨리 공기 적정성 검토연구)

  • Kim Kyong-Ju;Kim Byeong-Soo;Chun Jin-Ku;Lee Jeong-Hun;Yun Won-Gun
    • Proceedings of the Korean Institute Of Construction Engineering and Management
    • /
    • autumn
    • /
    • pp.495-499
    • /
    • 2003
  • As an alternative to overcome the limitations of current popular schedule system such as Bar Chart, PERT, CPM in proving the feasibility of a given project schedule and duration, this research applies simulation to the 'Shiwha Techno-Valley project, and then reviews its usability in time management. Shiwha-Techno-Valley is a gigantic project requiring large number of equipment and resulting in traffic congestion. In particular, project site is located near the Shiwha industrial complex and Daeboo-Do tourist place. Therefore, current traffic needs should not be ignored. This research evaluates whether the project can be finished in a given time even if construction equipment increase in addition to the current traffic. Through the analysis of the simulation output, the research identifies the optimal resource input and the needs on alternative schedule for the project.

  • PDF

Design of an Efficient User Authentication Protocol Using subgroup of Galois Field (유한체의 부분군을 이용한 효율적인 사용자 인증 프로로콜 설계)

  • 정경숙
    • Journal of the Korea Society of Computer and Information
    • /
    • v.9 no.2
    • /
    • pp.105-113
    • /
    • 2004
  • If the protocol has fast operations and short key length, it can be efficient user authentication protocol Lenstra and Verheul proposed XTR. XTR have short key length and fast computing speed. Therefore, this can be used usefully in complex arithmetic. In this paper, to design efficient user authentication protocol we used a subgroup of Galois Field to problem domain. Proposed protocol does not use GF($p^6$) that is existent finite field, and uses GF($p^2$) that is subgroup and solves problem. XTR-ElGamal based user authentication protocol reduced bit number that is required when exchange key by doing with upside. Also, Proposed protocol provided easy calculation and execution by reducing required overhead when calculate. In this paper, we designed authentication protocol that is required to do user authentication.

  • PDF

Optimization of Approximate Modular Multiplier for R-LWE Cryptosystem (R-LWE 암호화를 위한 근사 모듈식 다항식 곱셈기 최적화)

  • Jae-Woo, Lee;Youngmin, Kim
    • Journal of IKEEE
    • /
    • v.26 no.4
    • /
    • pp.736-741
    • /
    • 2022
  • Lattice-based cryptography is the most practical post-quantum cryptography because it enjoys strong worst-case security, relatively efficient implementation, and simplicity. Ring learning with errors (R-LWE) is a public key encryption (PKE) method of lattice-based encryption (LBC), and the most important operation of R-LWE is the modular polynomial multiplication of rings. This paper proposes a method for optimizing modular multipliers based on approximate computing (AC) technology, targeting the medium-security parameter set of the R-LWE cryptosystem. First, as a simple way to implement complex logic, LUT is used to omit some of the approximate multiplication operations, and the 2's complement method is used to calculate the number of bits whose value is 1 when converting the value of the input data to binary. We propose a total of two methods to reduce the number of required adders by minimizing them. The proposed LUT-based modular multiplier reduced both speed and area by 9% compared to the existing R-LWE modular multiplier, and the modular multiplier using the 2's complement method reduced the area by 40% and improved the speed by 2%. appear. Finally, the area of the optimized modular multiplier with both of these methods applied was reduced by up to 43% compared to the previous one, and the speed was reduced by up to 10%.

An Adaptive Temporal Suppression for Reducing Network Traffic in Wireless Sensor Networks (무선 센서 네트워크에서 통신량 감소를 위한 적응적 데이터 제한 기법)

  • Min, Joonki;Kwon, Youngmi
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.49 no.10
    • /
    • pp.60-68
    • /
    • 2012
  • Current wireless sensor networks are considered to support more complex operations ranging from military to health care which require energy-efficient and timely transmission of large amounts of data. In this paper, we propose an adaptive temporal suppression algorithm which exploits a temporal correlation among sensor readings. The proposed scheme can significantly reduce the number of transmitted sensor readings by sensor node, and consequently decrease the energy consumption and delay. Instead of transmitting all sensor readings from sensor node to sink node, the proposed scheme is to selectively transmit some elements of sensor readings using the adaptive temporal suppression, and the sink node is able to reconstruct the original data without deteriorating data quality by linear interpolation. In our proposed scheme, sensing data stream at sensor node is divided into many small sensing windows and the transmission ratio in each window is decided by the window complexity. It is defined as the number of a fluctuation point which has greater absolute gradient than threshold value. We have been able to achieve up about 90% communication reduction while maintaining a minimal distortion ratio 6.5% in 3 samples among 4 ones.

A scheme on strengthening of R.O.K reserved force (예비전력 정예화 방안)

  • Kim, Jae-Sam
    • Journal of National Security and Military Science
    • /
    • s.5
    • /
    • pp.1-45
    • /
    • 2007
  • Reserved forces of ROKA are in charge of replacement of TOE in the wartime and mission of rear area operation. But there is institutional inertia in the law and organization oriented to fill human resources rather than take mission. We need to prepare for the investment and arrangement of reserved forces as military power that would be replaced standing forces. In this portion, to reinforce reserve forces elite, First, efficient mobilization regulations and systems are suggested. I covered a maintenance of relevant mobilization ordinances which need to legislated and approved by national assembly for wartime and development of mobilization system which might lose the appropriate time for mobilization due to complicated declaration procedures and measures to overcome the panic at the initial stage of the war and organization and employment of nationwide transportation system and mobilization center. To ensure efficient resource management and mobilization of reserve forces with a number of approximately 3 million, there's a necessity of organization for integration and conciliation. To make it real, I suggested establishing and employing the mobilization center, on first phase, employ the mobilization center focusing on homeland divisions, on second phase, it is advisable to convert to national level mobilization system and develop to central mobilization center focusing on national emergency planning committee. During peacetime, in conjunction with Mobilization Cell, mobilization center can conduct resource survey and integrate and manage mobilization resources and take charge of mobilization training of subordinate units, and during wartime, in conjunction with mobilization coordination team and Cell, can ensure the execution of mobilization. Second, Future oriented reserve forces management system such as service system of reserve forces and support system of homeland defense operations. Current service and trainings of reserve forces by the year have very low connection, as it is very complex to manage the resources and trainings, and service and training lack the equity, re-establishment of service system is required. Also in an aspect of CSS and cultivation support for reserve forces, as the scope and limitation of responsibility between the armed forces and autonomous organization is obscure, conditions to conduct actual-fighting exercises are limited. Concentrated budgetting is extremely difficult because reserve forces training fields are scattered nationwide, and facilities and equipments are rapidly getting older. To improve all these, I suggest the organization of homeland defense battalion with a unit of "City-Gun-District" and supporting the local reserve forces. Conduct unit replacement or personal replacement for those who have finished their 1 or 2 years and homeland defense operation duty for those with 3-5 years for consistency and simplification. Third, I suggest Future oriented Reserved Training(FRT) and Training Center oriented training management to establish a reliable reserve training. Reserves carry out expansion of unit, conventional combat mission, homeland defense and logistics support during wartime, and actual-fighting exercise, and disaster relief, peace keeping activities. Despite diverse activities and roles, their training condition still stays definitely poor. For these reasons, Modernization of weapons and facilities through gradual replacement and procurement is essential to enhance mobilization support system.

  • PDF