Earticle

현재 국내의 지하 도로건설 가능성은 증가하고 있으며, 그동안 건설계획이 꾸준히 진행되어 왔다. 그러나 지금까지 지하도로의 특성, 관련 법규 및 설계 기준에 관한 연구는 활발히 진행되지 못하고 있는 실정이다. 본 연구에서는 이러한 배경을 고려하여 지하도로 건설에 필요한 기초적인 방향제시에 관한 내용을 다루고자 한다. 또한, 지하도로에 관한 국내외 사례를 중심으로 분석하고자 한다. 본 연구를 통한 주요 연구결과는 다음과 같다. 1) 지하도로의 선형 선정 시 지하공간 활용, 기술적요인 및 교통체계가 종합적으로 고려되어져야 한다. 2) 지하도로의 설계속도는 주행중 안전성을 확보하기 위하여 제한속도보다 10km/h정도 상회되도록 건설되어야 한다. 3) 비상상황에 대처하기 위하여 지하도로는 재난방지 시설 계획에 만전을 기하여야 한다. 본 연구의 제약상 지하도로 운전자의 특성에 대한 내용은 충분히 반영되고 있지 못하고 있으나 향후 지하도로 건설에 관한 개괄적인 방향제시에 관한 내용은 다루고 있다는 점에서 그 의의가 있을 것으로 판단된다.

Plans of underground roads have been established, and the possibilities of underground road constructions have been growing in Korea. However, the study on characteristics of underground roads, the enactment of law, and the establishment of design criteria haven’t been conducted so far, if any. Based on these backgrounds, the paper presents the basic direction on the construction method of underground roads. It also investigates the needs and characteristics of underground roads and reviews domestic and foreign examples. Major results by implementing the research are as follows: 1) when selecting the route of underground roads, the use of underground space, technical aspects, and traffic systems should be comprehensively considered; 2) the design speed of underground roads will be 10km/h above the speed limit to secure safety; 3) disaster prevention facilities should be planned to connect high traffic management system for coping with unexpected situations. Although this study has a limitation that hasn’t reflected the driver’s characteristics on new spaces such as underground roads, it has some significance that it suggests the major reviewing issues on the construction of underground roads, and presents the direction through the previous study.

There has been increasingly large demand for next generation high speed transport system to compliment air travel and for aerospace vehicle launchers for uses such as low orbit space transports. In this study, characteristics of two pulsed power accelerator designs commonly referred as Rail Gun and Gauss Gun were tested with the custom designed experimental set up. Velocity and various side effects during the operation of the accelerator, such as “suck-back” effect and rail erosion were noted and were used to achieve minimum set of controls defined as controlled acceleration, deceleration and deflection respectively. The experimental system with four sets of acceleration motors were able to achieve acceleration with measured energy efficiency peaking at 3 percent. It was concluded that the concept of transport system utilizing electromagnetic pulsed power system can be viable with relatively simple requirements while allowing unique designs without its form factor limited to conventional strictly linear path.

Electric motors, as the core of modern electric propulsion platforms, face increasing demands for high power density and lightweight designs. Conventional electric motors, relying on copper windings and iron cores, encounter significant limitations in meeting these requirements, particularly in applications such as aircraft and heavy-duty vehicles. High-temperature superconducting (HTS) tapes, characterized by their superior current-carrying capacity under critical conditions, offer a promising alternative. Motors incorporating HTS tapes demonstrate exceptional power-to-weight ratios, driving extensive research into replacing conventional motors. However, for mobility applications, HTS motors require optimized support structures designed to meet weight constraints. Unlike static applications of HTS coils, the support structure for a rotating superconducting rotor must ensure torque transmission and maintain cryogenic conditions while addressing both structural and thermal factors. This study focuses on the optimized design of the support structure for a superconducting rotor equipped with HTS coils. The proposed design is evaluated through finite element method (FEM) analysis, verifying its mechanical and thermal performance under operational conditions.

본 논문은 새로운 8-비트 AES (advanced encryption standard) 암호회로 설계를 제안한다. 대부분 8-비트 AES 암호회로는 성능을 희생시켜 하드웨어 크기를 줄인다. 제안한 AES는 2개의 분리된 S-box들을 갖고, 라운드 연산과 키 생성을 병렬로 연산함으로써, 고속 암호 연산이 가능하다. 제안된 AES 구조의 동작 실험 결과, 제안된 AES-128 구조의 최대 연산 지연은 13.0ns의 크기를 갖고, 77MHz의 최대 동작 주파수로 동작함을 확인하였다. 제안된 AES 구조의 성능은15.2Mbps가 된다. 결론적으로, 제안된 AES의 성능은 기존 8-비트 AES 구조에 비해 1.54배 향상된 성능을 갖고, 회로크기 증가는 1.17배 증가로 제한된다. 제안된 8비트 구조의 AES-128은 8비트 연산 구조 채택에 따른 성능 감소를 줄이면서 저면적 회로로 구현된다. 제안된 8비트 AES는 고속 동작이 필요한 IoT 어플리케이션에 활용될 것으로 기대된다.

This paper presents new 8-bit implementation of AES. Most typical 8-bit AES designs are to reduce the circuit area by sacrificing its throughput. The presented AES architecture employs two separated S-box to perform round operation and key generation in parallel. From the simulation results of the proposed AES-128, the maximum critical path delay is 13.0ns. It can be operated in 77MHz and the throughput is 15.2 Mbps. Consequently, the throughput of the proposed AES has 1.54 times higher throughput than the other counterpart although the area increasement is limited in 1.17 times. The proposed AES design enables very low-area design without sacrificing its performance. Thereby, it can be suitable for the various IoT applications that need high speed communication.

Because of environmental and resource depletion issue, there is a growing interest in eco-friendly vehicle, especially electric car. The small electric city car, called "Micro Mobility" has gained in popularity because of generalization of households under two or less members. In this study, to improve mechanical characteristics of Micron Mobility, 2-speed planetary transmission is designed, manufactured, and its efficiency is verified.

본 논문은 Cortex-M4 기반 STM32 프로세서를 이용한 고속 데이터수집 및 융합 시스템 설계에 대해서 기술하였다. 본 논문에서 설계한 데이터수집 시스템은 산업현장에서 발생되는 각종 데이터를 4 종류까지 실시간으로 수집하여 서버 컴퓨터로 자료를 전송할 수 있으며, 각종 센서와 연결이 간편하여 설치가 간단하고 간편한 필드-프레임을 개발해서 동작 속도를 매우 향상 시켰다. 또한 각종 센서를 쉽게 연결할 수 있도록 디지털 신호 입력부와 아나로그 신호 입력부를 별도로 두어서 서로 다른 센서에서 입력된 신호를 융합할 수 있게 설계되었다. 이러한 융합형 데이터수집 시스템은 실시간으로 각종 데이터의 동시 수집과 모터제어에 잘 동작하였으며 정밀제품의 품질향상에 크게 기여하리라 판단된다.

In this paper, we describe the design of a high speed data acquisition system(DAS) with STM32 processor based on Cortex-M4. The system is used for the sensor devices to collect raw data on production lines at factory and send them to the servo computer in real time. The system is designed for multi functions with universal asynchronous receiver and transmitter(UART), analog to digital converter(ADC), digital to analog converter(DAC), and general purpose input output(GPIO). those are well tested for various data acquisition and high speed motor control in real time.

The Automobiles with a combustion engine use a transmission for increasing drive force, reverse-move and maintaining non-load condition in general. In the Electric automobile system, output-axial can be operated just by controlling the motor manipulated with power. It also does not need reverse-gear by rotating the motor in the opposite direction. Designed to assemble two different types of planetary gear ratio and to be input torque of input-axial in sun gear and divide ring gear Ⅰ, Ⅱ and then after one of ring gear is fixed, in accordance with the planetary gear velocity ratio, the first gear has 0.136 decreased speed and second gear has 0.240 decreased speed, separately. While the planetary gear type transmission showed over the 92% of efficiency in the all of velocity range. The transmission proposed in this study can be expected to apply to the electric vehicle or others.

This study presents the design and FPGA implementation of a low-power, high-throughput digital modem for Medical Implant Communication System (MICS) applications. The proposed system applies a π /4-D8PSSK modulation technique to achieve high data efficiency while maintaining low power consumption. Implemented on a Xilinx Spartan-7 FPGA, the modem achieves a data rate of 16.4 ± 0.3 Mbps, with a power consumption of 0.6 ± 0.02 W/h, demonstrating a 40% improvement in energy efficiency compared to conventional 4FSK systems. The system satisfies IEEE 802.15.6 and ITU-R RS.1346 standards, with verified waveforms through MATLAB–Simulink and Chipscope. This work contributes to localization of medical implant communication technologies and provides a foundation for ASIC-based integration for next-generation biomedical and industrial wireless systems.

The initial hull form having a 3 gross tonnage and 30 knots class high speed leisure boat is newly developed based on a statistical analysis method. Fluid dynamics characteristics are studied by commercial CFD code, FLUENT. The effect of a fin attached on the hull side is investigated together. It can be found that the fin plays a role of increasing the resistance performan

Since 1970s, the rapid urbanization by Korean economic development causes change of surface roughness and global warming is affecting a rise in typhoons. therefore it is required to improve the basic wind speed map of Korean Building Code 2009 reasonably by applying the recent meterological data. this study shows building basic wind speed map by investigating regional meterological data(1973~2012) and estimating the design wind speed for Daegu-Gyeongbuk Region. thirteen cities is selected in this study for the past thirty years and the wind speed is calibrated by considering effective height of anemometer in hilly areas. we estimated the wind speeds for 100’s years return period including annual maximum, High temperature seasons, Low temperature seasons.

Recently, SDAS(Advanced driver-assistance system) are being installed to assist driving of vehicles and improve driver convenience. LDWS(Lane departure warning system) and FCWS(Forward collision warning system) are the core of the technology. Among these, FCWS is evaluated as a key assistive technology to prevent vehicle crashes. Accordingly, many algorithms are being developed and tested to improve detection speed and actual detection algorithms are being commercialized. In this paper, We propose the design of a system that optimizes FCWS speed by considering the AI performance of the terminal device when implemented as an embedded system.

영상처리를 이용한 차량 번호판 인식은 경찰의 범죄 추적과 무인 주차관리에서 많이 사용되고 있다. 특히 경찰은 속 도위반, 주정차 위반과 같은 범죄 차량 추적 등에 많이 사용한다. 추적을 위한 시스템은 카메라 이미지를 중앙 시스 템으로 전송하면, 중앙 시스템에서 이미지 처리를 통해 디지털 데이터로 변환한 정보와 데이터베이스에 저장된 범죄 차량 정보를 비교하여 범죄 차량 여부를 판단한다. 이로 인해 범죄 차량 여부의 확인까지 상대적으로 긴 시간과 높 은 비용이 발생하여 정보 획득과 빠른 범죄 차량 판단이 어렵다. 본 논문에서는 이러한 문제점을 해결하기 위해 차 량 번호판 정보를 저장하고 관리할 수 있는 파일 데이터베이스 구조와 효율적인 탐색을 위한 알고리즘을 제안한다. 차량 번호한은 한국 표준 번호판을 기준으로 작성하였고, 용도와 차량 등록번호를 이용한 2차원 배열 형태로 구성하 여 효율적으로 정보를 구조화하였다. 파일 데이터베이스의 성능 평가는 SQLite와 비교를 통해 탐색 알고리즘을 통 한 차량 정보의 빠른 접근을 증명하였다.

License plate recognition using image processing is widely used for police crime tracking and unmanned parking management. The tracking system transmits the camera image to the central system, and compares the information converted into digital data and the criminal vehicle information stored in the database through image processing in the central system to determine whether the vehicle is a criminal vehicle. This incurs a relatively long time and high cost until the identification of the crime vehicle, it is difficult to obtain information and quickly determine the crime vehicle. In this paper, to solve this problem, we propose a database structure for storing and managing license plate information and an algorithms for efficient retrieval. Vehicle number limit was prepared based on Korean standard license plate and structured information efficiently by constructing two-dimensional array form using purpose and vehicle registration number. The performance evaluation of the file database demonstrates the fast access of vehicle information through a search algorithm through comparison with SQLite.

This study develops an efficient numerical algorithm to predict wave-resistance performance of a catamaran hull. The developed numerical algorithm is applied to evaluate wave-resistance performance for two different twin hull forms with a asymmetric and a symmetric mono hull. Numerical calculations and model tests are compared to validate a developed numerical algorithm adopted in the current work. Comparisons are carried out through the sinkage at the bow and stern, the trim and the wave-making resistance coefficient. Model test is performed in order to verify the numerical results. The comparative analysis study regarding hydrodynamic characteristic of different twin hull forms is worthy of application in the catamaran hull form development stage.