• Journal of electromagnetic engineering and science
• /
• 제12권1호
• /
• pp.37-44
• /
• 2012

This paper describes a compact and novel wireless vital sign sensor at 2.4 GHz that can detect heartbeat and respiration signals. The oscillator circuit incorporates a planar resonator, which functions as a series feedback element as well as a near-field radiator. The periodic movement of a human body during aerobic exercise could cause an input impedance variation of the radiator within near-field range. This variation results in a corresponding change in the oscillation frequency and this change has been utilized for the sensing of human vital signs. In addition, a surface acoustic wave (SAW) filter and power detector have been used to increase the system sensitivity and to transform the frequency variation into a voltage waveform. The experimental results show that the proposed sensor placed 20 mm away from a human body can detect the vital signs very accurately.

• 정보처리학회논문지:소프트웨어 및 데이터공학
• /
• 제11권8호
• /
• pp.325-330
• /
• 2022

본 논문은 한국 수어에 대하여 수어 인식, 수어 번역, 수어 영상 시분할과 같은 수어에 관한 딥러닝 연구를 위한 데이터셋의 수집 및 실험을 진행하였다. 수어 연구를 위한 어려움은 2가지로 볼 수 있다. 첫째, 손의 움직임과 손의 방향, 표정 등의 종합적인 정보를 가지는 수어의 특성에 따른 인식의 어려움이 있다. 둘째, 딥러닝 연구를 진행하기 위한 학습데이터의 절대적 부재이다. 현재 알려진 문장 단위의 한국 수어 데이터셋은 KETI 데이터셋이 유일하다. 해외의 수어 딥러닝 연구를 위한 데이터셋은 Isolated 수어와 Continuous 수어 두 가지로 분류되어 수집되며 시간이 지날수록 더 많은 양의 수어 데이터가 수집되고 있다. 하지만 이러한 해외의 수어 데이터셋도 방대한 데이터셋을 필요로 하는 딥러닝 연구를 위해서는 부족한 상황이다. 본 연구에서는 한국 수어 딥러닝 연구를 진행하기 위한 대규모의 한국어-수어 데이터셋을 수집을 시도하였으며 베이스라인 모델을 이용하여 수어 번역 모델의 성능 평가 실험을 진행하였다. 본 논문을 위해 수집된 데이터셋은 총 11,402개의 영상과 텍스트로 구성되었다. 이를 이용하여 학습을 진행할 베이스라인 모델로는 수어 번역 분야에서 SOTA의 성능을 가지고 있는 TSPNet 모델을 이용하였다. 본 논문의 실험에서 수집된 데이터셋에 대한 특성을 정량적으로 보이고, 베이스라인 모델의 실험 결과로는 BLEU-4 score 3.63을 보였다. 또한, 향후 연구에서 보다 정확하게 데이터셋을 수집할 수 있도록, 한국어-수어 데이터셋 수집에 있어서 고려할 점을 평가 결과에 대한 고찰로 제시한다.

• 천문학회보
• /
• 제37권2호
• /
• pp.137.1-137.1
• /
• 2012

If all Coronal mass ejections (CMEs) have flux ropes, then the CMEs should keep their helicity signs from the Sun to the Earth according to the helicity conservation principle. We select 34 CME-ICME pairs whose source active regions (ARs) have continuous SOHO/MDI magnetogram data covering more than 24 hr without data gap during the passage of the ARs near the solar disk centre. The helicity signs in the ARs are determined by estimation of accumulating amounts of helicity injections through the photospheric surfaces in the entire source ARs. The helicity signs in the ICMEs are estimated by applying the cylinder model developed by Marubashi (2000) to 16 second resolution magnetic field data from the MAG instrument onboard the ACE spacecraft. It is found that 30 out of 34 events (88%) are helicity sign-consistent events, while 4 events (12%) are sign-inconsistent. Through a detailed investigation of the AR solar origins of the 4 exceptional events, we find that those exceptional events can be explained by the local AR helicity sign opposite to that of the entire AR helicity (2000 July 28 ICME), incorrectly reported solar source in CDAW (2005 May 20 ICME), or the helicity sign of the pre-existing coronal magnetic field (2000 October 13 and 2003 November 20 ICMEs). We conclude that the helicity signs of the ICMEs are quite consistent with those of the injected helicities in the AR regions where CMEs were erupted.

• IEIE Transactions on Smart Processing and Computing
• /
• 제4권4호
• /
• pp.237-250
• /
• 2015

This paper describes a hardware-oriented algorithm and its conceptual implementation in a real-time speed limit traffic sign detection system on an automotive-oriented field-programmable gate array (FPGA). It solves the training and color dependence problems found in other research, which saw reduced recognition accuracy under unlearned conditions when color has changed. The algorithm is applicable to various platforms, such as color or grayscale cameras, high-resolution (4K) or low-resolution (VGA) cameras, and high-end or low-end FPGAs. It is also robust under various conditions, such as daytime, night time, and on rainy nights, and is adaptable to various countries' speed limit traffic sign systems. The speed limit traffic sign candidates on each grayscale video frame are detected through two simple computational stages using global luminosity and local pixel direction. Pipeline implementation using results-sharing on overlap, application of a RAM-based shift register, and optimization of scan window sizes results in a small but high-performance implementation. The proposed system matches the processing speed requirement for a 60 fps system. The speed limit traffic sign recognition system achieves better than 98% accuracy in detection and recognition, even under difficult conditions such as rainy nights, and is implementable on the low-end, low-cost Xilinx Zynq automotive Z7020 FPGA.

• 한국측량학회:학술대회논문집
• /
• 한국측량학회 2007년도 춘계학술발표회 논문집
• /
• pp.221-224
• /
• 2007

MMS(Mobile Mapping System) generates a efficient image data for mapping and facility management. However, this image data of MMS has many difficulties in a practical use because of huge data volume. Therefore the important information likes road sign post must be extracted from huge MMS image data. In Korea, there is the HMS(Highway Management System) to manage a national road that acquire the line and condition of road from the MMS images. In the HMS each road sign information is manually inputted by the keyboard from moving MMS. This manually passive input way generate the error like inaccurate position, mistaking input in this research we developed the automatic road sign identifying technique using the image processing and the direct geo-referencing by GPS/INS data. This development brings not only good flexibility for field operations, also efficient data processing in HMS.

• Journal of Mechanical Science and Technology
• /
• 제19권6호
• /
• pp.1268-1279
• /
• 2005

The current method for pavement sign marking operations is labor-intensive and very dangerous due to the exposure of workers to passing traffic. It also requires blocking traffic for a long period of time resulting serious traffic jam. This paper deals with the development of a robotic system for automating the pavement sign painting operations. The robotic system consists of gantry frame equipped with transverse drive rail and automatic paint spray system. The workspace of the gantry robot is extended to one-lane width with the transverse rail system. This research also includes the development of font data structures that contain the shape information of pavement signs, such as Korean letters, English letters and symbols. The robot path is generated with this font data through the procedures of scaling up/down and partitioning the signs to be painted depending on the workspace size.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제11권6호
• /
• pp.3166-3187
• /
• 2017

For "generic" multivariate public key cryptography (MPKC) systems, experts believe that the Unbalanced Oil-Vinegar (UOV) scheme is a feasible signature scheme with good efficiency and acceptable security. In this paper, we address two problems that are to find inversion solution of quadratic multivariate equations and find another structure with some random Oil-Oil terms for UOV, then propose a novel signature scheme based on hyper-sphere (HS-Sign for short) which directly answers these two problems. HS-Sign is characterized by its adding Oil-Oil terms and more advantages compared to UOV. On the one side, HS-Sign is based on a new inversion algorithm from hyper-sphere over finite field, and is shown to be a more secure UOV-like scheme. More precisely, according to the security analysis, HS-Sign achieves higher security level, so that it has larger security parameters choice ranges. On the other side, HS-Sign is beneficial from both the key side and computing complexity under the same security level compared to many baseline schemes. To further support our view, we have implemented 5 different attack experiments for the security analysis and we make comparison of our new scheme and the baseline schemes with simulation programs so as to show the efficiencies. The results show that HS-Sign has exponential attack complexity and HS-Sign is competitive with other signature schemes in terms of the length of the message, length of the signature, size of the public key, size of the secret key, signing time and verification time.

• 한국재난정보학회 논문집
• /
• 제17권2호
• /
• pp.266-274
• /
• 2021

연구목적: 본 연구는 보행자의 안전 및 다양한 정보를 제공할 수 있는 바닥용 콘크리트 공공 사인 블록의 개발을 목적으로 한다. 연구방법: 이러한 연구목적을 달성하기 위하여 위하여 공공 사인 블록 개발과 관련하여 적용한 단계별 블록 제작 기술을 제시하고, 개발된 콘크리트 공공 사인 블록의 현장적용성을 평가하였다. 연구결과: 본 연구에서 개발된 바닥용 콘크리트 공공 사인 블록은 다양한 형상의 공공 사인의 표현이 가능하고, 제조 단가를 절감할 수 있을 것으로 보인다. 2년간의 사용성 평가결과 균열, 모서리 탈락, 변색, 마모 등의 문제는 발견되지 않아 충분한 내구성을 확보한 것으로 판단된다. 결론: 이러한 연구 결과를 토대로 콘크리트 공공 사인 블록이 기존의 바닥용 공공 사인에 활용되어 오던 스티커, 석재 및 황동판 등의 취약점을 보안할 수 있는 대안으로 활용될 것으로 보이며, 향 후 블록 디자인의 다양화를 도모하여 여러 분야에 적용될 수 있기를 기대한다.

• 기본간호학회지
• /
• 제17권2호
• /
• pp.209-219
• /
• 2010

Introduction: The phenomenon related to sign & symptom management for end of life of the patients is of interest to researchers in nursing society today. This study was conducted to clarify and to conceptualize the factors of sign & symptom management in end of life care though nurses' perceptions on this phenomena. Methods: The qualitative study method was used to explore the experienced nurses' perceptions related to sign & symptom management in end of life care. It included a field study carried out in South Korea using in-depth interviews with 30 experienced nurses from three nursing home facilities. Results: This study identified the following categories related to end of life care with sub-categories for each category: (1) nurses' modes in identifying the signs related to patients' end of life, (2) nurses' perceived directions on patients' end of life care, (3) nurses' perceived strategies in end of life care and (4) nurses' perceived barriers in end of life care Conclusion: Through this study, characteristics of the way nurses' provide for patients' end of life care are identified, along with how nursing decisions are made to manage the sign & symptom indicating patients' end of life.

• 대한공간정보학회지
• /
• 제19권3호
• /
• pp.91-98
• /
• 2011

도로표지는 운전자에게 안전하고 편안하게 목적지까지 안내를 목적으로 하는 교통시설이다. 도로표지는 신규노선이나 노선의 변경 그리고 도로표지의 노후화 등에 의해 지속적으로 현지조사와 이를 데이터베이스화하는 노력이 필요하다. 본 연구에서는 이러한 도로표지의 현지조사와 데이터베이스 구축을 효율적으로 수행할 수 있는 방안을 제시하는 것을 목적으로 하였다. 이를 위해 현지조사를 위한 모바일 매핑시스템을 설계하였다. 설계된 모바일매핑 시스템은 도로표지 영상정보를 획득할 수 있는 3대의 카메라, 차량의 위치와 자세를 알 수 있는 GPS/IMU/DMI, 그리고 도로표지 지점위치와 노선정보를 획득할 수 있는 레이저스캐너로 구성하였다. 또한 도로표지 영상에서 자동으로 도로표지 영역을 검출하고 이로부터 문자인식을 수행하는 절차를 제시하였다.