임베디드 시스템에서의 객체 탐지 네트워크의 가속을 위한 중요도 탐색 필터 가지치기 기법 연구

고현준,강 진 구,김용우 대한전자공학회 2024 전자공학회논문지 Vol.61 No.5

최근, 컴퓨터 기술이 발달하면서 CNN 기반의 객체 탐지 네트워크와 관련된 연구가 활발히 진행되고 있다. 하지만 많은 수의 CNN은 제한된 메모리와 연산량을 가지는 임베디드 환경에서의 추론을 어렵게 하는 원인이 된다. 이 문제의 대표적인 해결 방법으로 네트워크 가지치기 기법이 있다. 네트워크 가지치기 기법은 중복된 역할을 하는 파라미터를 제거하여 추론 시 요구되는 메모리와 연산량을 감소시켜 임베디드 보드에서의 추론을 용이하게 할 수 있다. 하지만 대부분의 가지치기 기법은 두 단계의 학습을 요구하여 많은 시간과 자원이 소모되고 가지치기에 따른 채널의 관계 변화를 반영하지 못해 최적의 경량 네트워크를 보장할 수 없다. 따라서 본 논문에서는 최적의 경량 네트워크를 얻기 위한 중요도 탐색 기법을 제안하고 가지치기의 과정을 단순화하여 한 단계의 훈련만으로 가지치기가 가능한 중요도 탐색 필터 가지치기 기법을 제안한다. 본 논문에서는 VGG-16과 ResNet-50을 백본 네트워크로 가지는 SSD 네트워크에 가지치기를 적용하고 Jetson Xavier NX에서 추론 속도를 측정하였다. ResNet-50을 이용하는 네트워크에서 실험 결과 mAP(0.5)는 가지치기 비율에 따라 0.5 %, 0.7 %, 1.0 % 감소하였지만, 추론 시간은 12.75 %, 16.03 %, 21.66 % 향상되었다. 또한 학습 시간은 다른 기법보다 최대 43.85 % 빠르며 유사한 가지치기 비율의 네트워크와 비교할 때 높은 성능을 가진다. In recent years, with the development of computer technology, research on CNN-based object detection networks has been actively conducted. However, a large number of CNNs can make inference difficult in embedded environments with limited memory and computation. A typical solution to this problem is network pruning. Network pruning can facilitate inference on embedded boards by reducing the amount of memory and computation required by removing redundant parameters. However, most pruning methods require two stages of training, which consumes a lot of time and resources, and cannot guarantee an optimal lightweight network because they cannot reflect the changes in channel relationships due to pruning. Therefore, this paper proposes an importance search method to obtain an optimal lightweight network, and simplifies the pruning process to propose an importance search filter pruning method that can be pruned with only one stage of training. In this paper, we apply pruning to the SSD network with VGG-16 and ResNet-50 as the backbone network, and measure the inference speed on Jetson Xavier NX. In the network using ResNet-50, the experimental results showed that mAP(0.5) decreased by 0.5%, 0.7%, and 1.0% depending on the pruning ratio, but inference time improved by 12.75%, 16.03%, and 21.66%. In addition, the learning time is up to 43.85% faster than other methods and has high performance when compared to networks with similar pruning ratios.

Thrombin-induced Sensitivity Enhancement in Impedemetric Detection of Hg2+ Ion

고현준,Shigeori Takenaka,김규원 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.4

저온형 SOFC용 GDC 전해질 두께에 따른 Open Circuit Voltage 향상

고현준,이종진,현상훈 한국세라믹학회 2010 한국세라믹학회지 Vol.47 No.2

It has been considered to apply GDC (Gd0.1Ce0.9O1-X) for low-temperature SOFC electrolytes because it has higher ionic conductivity than YSZ at low temperature. However, open circuit voltage with using GDC (Gd0.1Ce0.9O1-X) electrolyte in SOFCs, becomes lower than using YSZ (8 mol% Yttria stabilized Zirconia) electrolyte because GDC has electronic conductivity. In this work, the effect of changing GDC electrolyte thickness on the open circuit voltage has been investigated. Ni-GDC anode-supported unit cells were fabricated as follows. Mixed NiO-GDC powders were pressed and pre-sintered at 1200oC. And then, GDC electrolyte material was dip-coated on the anode and sintered at 1400oC. Finally the LSCF-GDC cathode material was screen-printed on the electrolyte and sintered at 1000oC. Electrolyte thickness was controlled by the number of dip-coating times. Open circuit voltage was measured depending on electrolyte thickness at 650oC and found that the thicker GDC electrolyte was, the better OCV was.

침대 이송 기능을 갖춘 수동식 휠체어 설계

고현준,김남열,현정근,정우철,강모원,김종형 한국생산제조학회 2013 한국생산제조학회지 Vol.22 No.3

In general, manual wheelchairs have played important roles in moving patients from one place to another. However, patients have experienced discomfort getting on and off because of the need for physical assistance. This can be more serious if a patient has handicaps involving the arms or legs. In addition, it could be unpleasant for both the patient and assistant because of the need for extensive physical contact with each other. At times, a weak nurse feels that there is a risk when transferring a heavy patient from a bed to a wheelchair. In this paper, a new non-powered wheelchair is designed to assist in transferring a patient to their bed. This design considers the convenience of both the patient and assistant when the patient is transferred from a wheelchair to a bed and vice versa. The operation minimizes the physical contact between the assistant and the patient. The new wheelchair is also lightweight and portable compared with the normal popular wheelchair.

저온형 고성능 NiO-Fe₂O₃-GDC 연료극 지지형 SOFC 단위전지 개발

고현준,이종진,현상훈 한국에너지공학회 2009 한국에너지공학회 학술발표회 Vol.2009 No.9

춘천 산사태에서의 재난의료 대응팀(Disaster Medical Assistant Team)의 역할및 산사태 재난의 특징

고현준,김오현,차용성,차경철,김 현,황성오,안무업,조준휘,이강현 대한응급의학회 2013 대한응급의학회지 Vol.24 No.5

Purpose: The purpose of this study was to analyze the expierience of the Wonju Disaster Medical Assistant Team (DMAT)’s activities during the Chun-cheon landslide (AM 00:08 on July 7th, 2011) and to present damages caused by the landslide. The scale of the domestic DMAT in the landslide disaster was also assessed. Methods: In a retrograde study, victims were analyzed video camera recordings and medical records at the landslide disaster. Follow-up surveys of patients taken to the hospital after the Chun-cheon landslide were also analyzed. In addition, pertinence of the Wonju DMAT’s activities during the rescue activity, designated by National Emergency Management, were evaluated. Results: Rescue efforts continued until 13:00 on July 7th,2011. The number of casualties was forty one, consisted of three immediate patients, six delayed patients, nineteen minimal patients, and thirteen expectant patients. The Wonju DMAT arrived at the scene of the landslide disaster at AM 02:30 on July 7th, 2011. After installing a medical office, they categorized patients by ID-ME classification and provided medical treatment to twenty-two patients, including local residents and rescue workers. Conclusion: The cause of death in the landslide disaster was suffocation. A small-scale DMAT rescue, composed on five to six people, is more proper for disaster response in a landslide disaster.

실험계획법을 활용한 풍동실험의 효율성 및 생산성 향상에 관한 연구

고현준,박성연,김재우,권기범 한국항공우주학회 2015 한국항공우주학회 학술발표회 논문집 Vol.2015 No.11

풍동실험에 소요되는 시간과 비용을 절감하고자 적은 수의 풍동실험 결과를 가지고 실험계획법(Design of Experiment, DOE)을 이용하여 생성한 공력반응모델이 기존의 OFAT(One Factor At a Time) 방식의 실험을 통해 획득되는 공력계수 예측에 적합한지를 판단하고 이러한 모델의 활용 가능성에 대한 연구를 수행하였다. 1차적으로 받음각, 옆미끄럼각, 유속을 실험변수로 설정하여 실험하고, Effect Screening Test를 통해 유속을 변수에서 제외하였다. 실험계획법으로 라틴정방설계법(Latin Hypercube Design, LHD)과 중심합성설계법(Central Composite Design)을 사용하여 실험을 계획하였고 반응모델로는 반응표면모델과 인공신경망모델이 고려되었으나 검증 결과 인공신경망모델의 정확성이 더 높다고 판단하여 인공신경망 모델을 채택하였다. 기존의 OFAT 방식으로 수행한 풍동실험으로 얻은 T-50 축소모형의 데이터와 인공신경망모델의 예측값을 비교하여 해당 모델이 공력계수 예측에 적합한지 판단하고 실험계획법이 풍동실험의 효율성과 생산성 향상에 기여할 수 있는 가능성을 분석하였다. A study is conducted to decide suitability of prediction model for estimating aerodynamic coefficients created by using DOE(Design Of Experiment) to reduce time and cost in wind tunnel tests. First, angle of attack, side slip angle, and flow velocity are selected as test variables and flow velocity is excluded after effect screening test. LHD(Latin Hypercube Design) and CCD(Central Composite Design) are used for designing the experiment. In order to create the metamodel, NN(Neural Network) model is chosen because it is more accurate than RSM(Response Surface Model) in prediction accuracy. The test data of T-50 5% model acquired by usual OFAT(One Factor At a Time) is compared with the prediction values estimated by NN prediction model. The adequacy and applicability of the model is analyzed to show the possibility of improvement in efficiency and productivity of wind tunnel tests using DOE.

다개체 로봇 정찰 시스템의 구현

고현준,장경재,장동휘,김종형 제어로봇시스템학회 2016 제어로봇시스템학회 국내학술대회 논문집 Vol.2016 No.3

공기주입에 따른 양돈분뇨중 악취제거 특성 연구

고현준,김명중,신경섭,양진모,이명규 한국축산시설환경학회 1997 축산시설환경학회지 Vol.3 No.2

This study was conducted to investigate the removal effect of malodorous substances of piggery wastes by air injection. With 7% of TS weight of artificial piggery wastes, this study focused on the changes of the concentration of VFAs, H2S during treatment period of 14 days. As a results of this study, air injection volume for removal of malodorants in this study was 150$m\ell$ / min$.$l$.$Under this condition, we found the concentrations of VFAs, H2S, NH3 have very high relationship with the pH, ORP, BOD, {{{{ { NH}`_{4 } ^{+ } }}-N. Especially, the concentration of Volatile Fatty Acids, one of most offensive odorants and one of BOD compounds were depended on ORP which can be controled by air injection in artificial piggery wastes.

Heterologous expression and characterization of endocellulase from the Japanese pine sawyer Monochamus saltuarius (MsGHF5)

고현준,권혁민,고현진,류지현,송휘승,박용철 한국곤충학회 2015 Entomological Research Vol.45 No.1

In this study, the endocellulase gene from Monochamus saltuarius (MsGHF5) was transformed into Escherichia coli (RosettaBlue(DE3)pLysS strain), and induced by IPTG. The molecular weight of recombinant MsGHF5 (rMsGHF5) was 78 kDa and was expressed as a fusion protein with maltose binding protein in pMAL‐c2 expression vector. Native‐PAGE was conducted with 0.1% carboxymethyl cellulose as a substrate, and the zymogenic bands were observed. The Michaelis constant and maximum velocity of rMsGHF5 were 0.199 mg/mL and 0.034 μmol/min/mL, respectively. The optimal condition for rMsGHF5 occurred at pH 5 and 30°C. Fe2+ and Mn2+ stimulated the activity of rMsGHF5 by 167 and 114% respectively, whereas Cu2+, Hg2+ and Zn2+ inhibited its activity.