• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 1999년도 추계종합학술대회 논문집
• /
• pp.376-379
• /
• 1999

The wavelet transform chip is implemented with Daubechies' 4 tap filter. It works at 20MHz in Field Programmable Gate array (FPGA) implementation of Quadrature Mirror Filter(QMF) Lattice Structure. In this paper, the structure contains taro-channel quadrature mirror filter, data format converter(DFC), delay control unit(DCU), and three 20$\times$8 bits real multiplier. The structures for the DFC and DCU need to he regular and scalable, require minimum number of regular, and thereby lead to an efficient and scalable architecture for the Discrete Wavelet Transform(DWT). These results present the possibility that it can be used in Digital Signal Processing(DSP) application faster than Fourier transform at small area with lour cost.

• 한국조명전기설비학회:학술대회논문집
• /
• 한국조명전기설비학회 2005년도 학술대회 논문집
• /
• pp.167-172
• /
• 2005

This study based on the experimental data on the daylight responsive dimming systems performance. The purpose of this study increases the energy-saving effects by reducing excessive intensity of radiation of artificial lighting through analyzing incident daylight. The photosensor sends amounts of detected luminous flux to digital control unit(DCU) as a signal and then, it can decide dimming ratios, by received a proper dimming signal from DCU. Generally it is effective to control artificial lighting with the different control ratio of each row by setting a photosensor as same numbers and rows as artificial lighting. However, it is ineffective to do in initial costs of systems aspect in offices. By analyzing the data of this performance and finding regular ration between photosensors. we will execute different dimming ratios to each row of artificial lighting by a single photosensor.

• 전기학회논문지
• /
• 제61권1호
• /
• pp.155-161
• /
• 2012

The firmware upgrade, which is remotely performed, is an essential function in smart metering or AMI (Advanced Metering Infrastructure). In other words, the AMI software and firmware can be switched for maintaining and improvement without replacement of H/W devices in AMI environment. Also, if number and type of devices are increase, the demand of remote update service will be increased. Through the firmware upgrade service remotely, the electric power corporation may be able to benefit various fields. For example, there are to adapt more easily in many environments, real-time service and to cut maintenance costs. In this paper, we proposed to design an international level FUMS(Firmware Upgrade Management System) which includes requirement function, architecture and protocol related with DCU, Smart Meter.

• 천문학회보
• /
• 제32권1호
• /
• pp.44.1-44.1
• /
• 2007

• 한국자동차공학회논문집
• /
• 제18권6호
• /
• pp.76-83
• /
• 2010

Recently, as the current and future emission regulations go stringent, the research of NOx reduction has become a subject of increasing interest and attention in diesel engine. Selective Catalytic Reduction (SCR) is one of the effective technology to reduce NOx emission from diesel engine. Especially, Urea-SCR that uses urea as a reductant is becoming increasingly popular as a cost effective way of reducing NOx emissions from heavy duty vehicles. In this research, we designed urea injector and DCU (Dosing Control Unit) specially developed for controlling the Urea-SCR process onboard vehicles. As passenger and commercial diesel engine experiment, we grasped characteristics of NOx emission and SCR catalyst temperature level in advance. As a result, highest NOx emission level was shown in condition of low engine speed and high load. On the other hand, SCR catalyst temperature was highest at high engine speed and load. On the basis of these result, we conducted the NOx reduction test at steady engine operating conditions using the urea injector and DCU. It was shown that 74% NOx conversion efficiency on the average and 97% NOx conversion efficiency was obtained at high SCR catalyst temperature.

• Journal of Communications and Networks
• /
• 제18권1호
• /
• pp.50-64
• /
• 2016

Nowadays, smart meter (SM) technology is widely effectively used. In addition, power allocation (PA) and channel selection (CS) are considered problems with many proposed approaches. In this paper, we will suggest a specific scenario for an SM configuration system and show how to solve the optimization problem for transmission between SMs and the data concentrator unit (DCU), the center that collects the data from several SMs, via simulation. An efficient CS with PA scheme is proposed in the TV white space system, which uses the TV band spectrum. On the basic of the optimal configuration requirements, SMs can have a transmission schedule and channel selection to obtain the optimal efficiency of using spectrum resources when transmitting data to the DCU. The optimal goals discussed in this paper are the maximum capacity or maximum channel efficiency and the maximum allowable power of the SMs used to satisfy the quality of service without harm to another wireless system. In addition, minimization of the interference to the digital television system and other SMs is also important and needs to be considered when the solving coexistence scenario. Further, we propose a process that performs an interference analysis scheme by using the spectrum engineering advanced Monte Carlo analysis tool (SEAMCAT), which is an integrated software tool based on a Monte-Carlo simulation method. Briefly, the process is as follows: The optimization process implemented by genetic evolution optimization engines, i.e., a genetic algorithm, will calculate the best configuration for the SM system on the basis of the interference limitation for each SM by SEAMCAT in a specific configuration, which reaches the solution with the best defined optimal goal satisfaction.

• 한국컴퓨터정보학회논문지
• /
• 제28권7호
• /
• pp.1-9
• /
• 2023

현재, 고속열차 보급이 증가하면서 도심구간의 정차 요구가 증대됨에 따라 도심구간의 고상 플랫폼과 시외구간의 저상 플랫폼 모두 운용이 가능한 열차 개발이 요구되고 있다. 본 논문에서는 저상과 고상 플랫폼에서 사용할 수 있는 플러그인 타입으로 저상과 고상 스텝으로 구성된 열차 측 출입문용 제어기의 설계 및 제작에 관하여 연구하였다. DCU H/W는 32bit MCU를 사용하여 4개의 모터를 제어하고, 33개의 Digital Input과 16개의 Digital Output이 가능하도록 설계하여 구현하였으며, 동작 SW는 EN50128의 소프트웨어 수명 주기에 따라 동작 요구 사항 2개 항목과 제어 요구 사항 12개 항목을 도출하여 설계 구현한 후 각 요구 사항에 대한 시험을 수행하였다. 그 결과 전체 요구 사항 14개 항목 중 목업에서 시험 가능한 13개 항목에 대하여 시험을 수행하였고, 요구 사항을 만족함을 보였다.

• 전기학회논문지P
• /
• 제60권3호
• /
• pp.110-113
• /
• 2011

Platform Screen Door, PSD, is a device that seeks to prevent accidents with regards to falling off the platform and getting trapped between the trains, achieve improvements on the cleanliness of the air, address the accessibility issue of the disabled and the elderly and provide fresher environment on the platform in general. This is achieved by preventing health hazards and accidents from occurring through installation of fixed and moving doors between rail, tram and subway platforms and the railway. Domestic firms have achieved domestic production to a large degree in various Control Units including the Overall Control Unit and RF devices through investments in technology. Despite this, full domestic production of the core of the PSD system, Door Control Unit, DCU, is not yet achieved, having to install PSDs in a relatively short period of time. Currently, controllers with DC motors are developed for installation or one is faced with having to import foreign produced controllers. In this research, the control unit prototype using the BLDC motor was domestically produced. The performance of the control unit was rigorously tested through installation on Eun-Ha Rail on Wol-Mi Island.

• 조명전기설비학회논문지
• /
• 제21권1호
• /
• pp.1-9
• /
• 2007

본 연구는 실내로 유입되는 주광을 조광제어시스템의 적용에 효율적으로 활용하여 초과한 인공조명의 광량을 줄임으로써 에너지 절약의 효과를 높이고자 함이다. 광센서는 탐지된 광속량을 신호로 보내고 그에 알맞은 제어신호를 받아 조광율을 결정하는데, 일반적으로 사무공간에서 인공조명의 개수나 행수만큼 광센서가 설치가 되어 조명기구의 각 구역마다 다른 조광율로 조광제어를 하는 것이 인공조명 제어측면에서는 효율적이나, 시스템 설치비용측면에서는 비효율적이다. 그러므로 실험과 시뮬레이션을 통하여 미리 유입되는 주광 분포를 파악하고 조광율을 분석한다면, 하나의 광센서 설치로써 인공조명 구역간의 각기 다른 조광율로 제어가능하다.

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제8권5호
• /
• pp.423-433
• /
• 2016

In this paper, we consider the cybersecurity issue of ship information system (SIS) from a new perspective which is called opacity. For a SIS, its confidential information (named as "secret") may be leaked through the working behaviors of each Distributed Control Unit (DCU) from an outside observer called an "intruder" which is able to determine ship's mission state by detecting the source of each data flow from the corresponding DCUs in SIS. Therefore we proposed a dual layer mechanism to enforce opacity by activating non-essential DCU during secret mission. This mechanism is calculated by two types of insertion functions: Safety-assured insertion function ($f_{IS}$) and Admissibility-assured insertion function ($f_{IA}$). Due to different objectives, $f_{IS}$ is designed to confuse intruder by constructing a non-secret behaviors from a unsafe one, and the division of $f_{IA}$ is to polish the modified output behaviors back to normal. We define the property of "$I_2$-Enforceability" that dual layer insertion functions has the ability to enforce opacity. By a given mission map of SIS and the marked secret missions, we propose an algorithm to select $f_{IS}$ and compute its matchable $f_{IA}$ and then the DCUs which should be activated to release non-essential data flow in each step is calculable.