상관관계 기반 특징 선별 기법을 사용한 걸음걸이 기반 성별 분류

권범(Beom Kwon) 한국컴퓨터정보학회 2024 韓國컴퓨터情報學會論文誌 Vol.29 No.3

성별 분류 기술은 법의학, 감시 시스템, 인구 통계 연구 등 다양한 분야에서 활용될 수 있기 때문에, 연구자들로부터 많은 관심을 받고 있다. 남성과 여성의 보행 사이에는 서로 구별되는 특징이 있다는 것이 기존 연구들에서 밝혀지면서, 3차원 보행 데이터에서 성별을 분류하는 다양한 기술들이 제안됐다. 하지만, 기존 기술들을 사용해 3차원 보행 데이터로부터 추출한 보행 특징 중에는 서로 유사 또는 중복되거나 성별 분류에 도움이 되지 않는 특징들도 있다. 이에 본 연구에서는 상관관계 기반 특징 선별 기술을 활용해, 성별 분류에 도움이 되는 특징들을 선별하는 방법을 제안한다. 그리고 제안하는 특징 선별 기술의 효용성을 입증하기 위해서, 인터넷상에 공개된 3차원 보행 데이터 세트(Dataset)를 활용하여 제안하는 특징 선별 기술을 적용하기 전과 후에 대해 성별 분류 모델들의 성능을 비교 분석하였다. 실험에는 이진 분류 문제에 적용할 수 있는 여덟 가지의 머신러닝 알고리즘(Machine Learning Algorithms)을 활용하였다. 실험 결과, 제안하는 특징 선별 기술을 사용하면 성별 분류 성능은 유지하면서, 특징의 개수를 82개에서 60개까지, 22개를 줄일 수 있다는 것을 입증하였다. Gender classification techniques have received a lot of attention from researchers because they can be used in various fields such as forensics, surveillance systems, and demographic studies. As previous studies have shown that there are distinctive features between male and female gait, various techniques have been proposed to classify gender from three dimensional(3-D) gait data. However, some of the gait features extracted from 3-D gait data using existing techniques are similar or redundant to each other or do not help in gender classification. In this study, we propose a method to select features that are useful for gender classification using a correlation-based feature selection technique. To demonstrate the effectiveness of the proposed feature selection technique, we compare the performance of gender classification models before and after applying the proposed feature selection technique using a 3-D gait dataset available on the Internet. Eight machine learning algorithms applicable to binary classification problems were utilized in the experiments. The experimental results show that the proposed feature selection technique can reduce the number of features by 22, from 82 to 60, while maintaining the gender classification performance.

MIMO 기술 적용을 위한 QAM 기반 FBMC 시스템

권범(Beom Kwon),최낙연(Nakyeon Choi),강지우(Jiwoo Kang),이상훈(Sang-Hoon Lee),김도영(Do-Young Kim),전동현(Donghyeon Jeon),이상훈(Sanghoon Lee) 한국통신학회 2014 한국통신학회 학술대회논문집 Vol.2014 No.1

네트워크 에너지 효율 증대를 위한 기지국의 전송 전력 결정 기법

권범(Kwon-Beom),김성현(Seonghyun Kim),이호재(Hojae Lee),이상훈(Sanghoon Lee) 한국통신학회 2013 한국통신학회 학술대회논문집 Vol.2013 No.1

걸음걸이 데이터에서 분노 검출을 위한 다중 시간 윈도 특징 추출 기술

권범(Beom Kwon),오태근(Taegeun Oh) 한국컴퓨터정보학회 2023 韓國컴퓨터情報學會論文誌 Vol.28 No.4

본 논문에서는 보행자의 걸음걸이로부터 분노 감정 검출을 위한 다중 시간 윈도 특징 추출 기술을 제안한다. 기존의 걸음걸이 기반 감정인식 기술에서는 보행자의 보폭, 한 보폭에 걸리는 시간, 보행 속력, 목과 흉부의 전방 기울기 각도(Forward Tilt Angle)를 계산하고, 전체 구간에 대해서 최솟값, 평균값, 최댓값을 계산해서 이를 특징으로 활용하였다. 하지만 이때 각 특징은 보행 전체 구간에 걸쳐 항상 균일하게 변화가 발생하는 것이 아니라, 때로는 지역적으로 변화가 발생한다. 이에 본 연구에서는 장기부터 중기 그리고 단기까지 즉, 전역적인 특징과 지역적인 특징을 모두 추출할 수 있는 다중 시간 윈도 특징 추출(Multi-Time Window Feature Extraction) 기술을 제안한다. 또한, 제안하는 특징 추출 기술을 통해 각 구간에서 추출된 특징들을 효과적으로 학습할 수 있는 앙상블 모델을 제안한다. 제안하는 앙상블 모델(Ensemble Model)은 복수의 분류기로 구성되며, 각 분류기는 서로 다른 다중 시간 윈도에서 추출된 특징으로 학습된다. 제안하는 특징 추출 기술과 앙상블 모델의 효과를 검증하기 위해 일반인에게 공개된 3차원 걸음걸이 데이터 세트를 사용하여 시험 평가를 수행했다. 그 결과, 4가지 성능 평가지표에 대해서 제안하는 앙상블 모델이 기존의 특징 추출 기술로 학습된 머신러닝(Machine Learning) 모델들과 비교하여 최고의 성능을 달성하는 것을 입증하였다. In this paper, we propose a technique of multi-time window feature extraction for anger detection in gait data. In the previous gait-based emotion recognition methods, the pedestrians stride, time taken for one stride, walking speed, and forward tilt angles of the neck and thorax are calculated. Then, minimum, mean, and maximum values are calculated for the entire interval to use them as features. However, each feature does not always change uniformly over the entire interval but sometimes changes locally. Therefore, we propose a multi-time window feature extraction technique that can extract both global and local features, from long-term to short-term. In addition, we also propose an ensemble model that consists of multiple classifiers. Each classifier is trained with features extracted from different multi-time windows. To verify the effectiveness of the proposed feature extraction technique and ensemble model, a public three-dimensional gait dataset was used. The simulation results demonstrate that the proposed ensemble model achieves the best performance compared to machine learning models trained with existing feature extraction techniques for four performance evaluation metrics.

병렬 분산 처리를 이용한 영상 기반 실내 위치인식 시스템의 프레임워크 구현

권범(Beom Kwon),전동현(Donghyun Jeon),김종유(Jongyoo Kim),김정환(Junghwan Kim),김도영(Doyoung Kim),송혜원(Hyewon Song),이상훈(Sanghoon Lee) 한국통신학회 2016 韓國通信學會論文誌 Vol.41 No.11

IEEE 802.16e에서 향상된 전력 절약 기법

권범(Beom Kwon),정윤원(Yon Won Chung) 한국정보기술학회 2012 한국정보기술학회논문지 Vol.10 No.8

Energy saving of battery in mobile station (MS) operating with battery is an essential problem to solve in order to support efficient mobile communication services. In IEEE 802.16e standard, Types I, II, and III sleep modes have been standardized for efficient energy saving of MSs for real-time, non-real-time, and multicast services. However Types I, II, III sleep modes have a drawback, where the efficiency of energy saving decreases as the number of sessions increases. In this paper, we propose an improved energy saving scheme which reduces energy consumption, by defining efficient sleep and listening windows, when an MS uses multiple Types I and II service sessions. Simulation results show that the proposed scheme has an improved energy saving than conventional schemes.

산양(山羊)에 있어서 Potassium 및 Urea가 Magnesium의 대사(代謝)에 미치는 영향(影響)

권오덕,이현범,Kwon, Oh-deog,Lee, Hyun-beom 대한수의학회 1985 大韓獸醫學會誌 Vol.25 No.1

In the present studies, the effects of dietary high-potassium and high-urea on the metabolism of magnesium, calcium and potassium were checked as an aid to clarify the pathogenesis of hypomagnesaemia(so-called grass tetany) in ruminant. A total of 5 Korean native female goats kept in metabolic cage were received high-potassium(Mg: 0.25%, Ca: 0.94%, K: 5.41%), high-urea(Mg: 0.25%, Ca: 0.94%, K: 0.72%) or control(Mg: 0.25%, Ca: 0.94, K: 0.72%) ration for 15 or 21 days. Daily intakes, fecal and urinary excretions and serum concentrations of magnesium, calcium and potassium were measured with an atomic absorption spectrophotometer. The results obtained were summarized as follows: In high-potassium group, absorption, urinary excretion and serum concentration of magnesium were significantly (p<0.01, p<0.01 and p<0.05 respectively) decreased compared with the control group. On the other hand, the body retention was significantly (p<0.01) increased. However, no clinical symptom of hypomagnesaemic tetany was observable throughout the experimental period. No significant effects on the metabolism and seurm content of calcium were detected in the high-potassium group. In the high-potassium group, significant increase in absorption (p<0.01), urinary excretion (p<0.05) and body retention (p<0.01) of potassium were recognized. However, no significant difference in the concentration of serum was observable between the two groups. In high-urea group, no significant difference in the metabolism of magnesium and potassium or in the serum content were recognized compared with the control group. In high-urea group, tthe absorption, urinary excretion, body retention and serum content of calcium were decreased compared with the control group.

Elk(Alces alces)에 발생(發生)한 Babesiosis

이현범,장인호,이근우,권오덕,김성호,Lee, Hyun-Beom,Jang, In-Ho,Lee, Kuen-Woo,Kwon, Oh-Deog,Kim, Seong-Ho 대한수의학회 1983 大韓獸醫學會誌 Vol.23 No.1

Authors encountered a case of elk babesiosis in Daegu, Korea. The main symptoms observed before the death of the patient were elevated rectal temperature, severe degree of hemoglobinuria, icterus and recumbency. Hematologically, the erythrocyte count was 1.93 million per cu.mm 11% of which were infected with Babesia. Most(88%) of the protozoa were spherical or vacuolated ring form in shape, resembling B. bovis. However, the sizes (0.98-2.85) were slightly smaller than the latter. About 7% of the protozoa were vacuolated oval, the size of which varied from $2.06{\sim}2.95{\times}1.08{\sim}1.97$ ($2.53{\times}1.51$ in average). The remaining 5% were irregular in shape. Pear-shaped were scarcely observed. A three-gears-old Korean native cattle was inoculated subcutaneously with the elk's blood. However, no evidence of susceptibility was observed until 30 days postinoculation.

산양의 실험적 납중독에 관한 임상병리학적 관찰 I. 임상학적 관찰(증상, 혈액, 뇨)

권오덕,이현범,이주묵,채준석,Kwon, Oh-deog,Lee, Hyun-beom,Lee, Joo-mook,Chae, Joon-seok 대한수의학회 1992 大韓獸醫學會誌 Vol.32 No.1

Present experiments were undertaken in order to clarify the clinico-pathological characteristics of lead poisoning in goats. Twenty goats were divided into three experimental groups(A, B and C) and a control(D). The three experimental groups received diets contaminated artificially with 10(A group), 200(B group) and 1,000(C group) ${\mu}g/$ of lead, for 70 days respectively. The control group received normal diets. Blood samples were collected 1 or 2 weeks interval and were examined for anemia(erythrocyte counts, hemoglobin concentrations and hematocrit values) and lead contents of erythrocyte and serum. Urine samples collected similarly with blood were examined for delta-aminolevulinic acid and lead content. Collected samples were analyzed for lead content by atomic absorption spectrophotometry. From these experiments following results were obtained : In group B and C, marked decreases in body weight and feed intake, and diarrhea were observed from the $30^{th}$ day of experimental periods. The B and C groups showed pronounced anemia(decrease in erythrocyte count, hemoglobin concentration and hematocrit value) from the $21^{st}$ or $42^{nd}$ day. In group B and C, the lead content of erythrocytes was increased significantly from the $28^{th}$ or $14^{th}$ day. The lead content of serum was increased significantly from the $42^{nd}$ or $14^{th}$ day in B and C groups. The lead content of urine was increased significantly from the first day in both B and C groups. The urinary delta-aminolevulinic acid content was increased significantly from $14^{th}$ day in both B and C groups.

돼지 흉막폐렴(胸膜肺炎)의 발생(發生)

이현범,이근우,박후열,권오덕,Lee, Hyun-beom,Lee, Keun-woo,Park, Hoo-yeol,Kwon, Oh-deog 대한수의학회 1984 大韓獸醫學會誌 Vol.24 No.1

Authors observed an outbreak of porcine pleuropneumonia at a piggery in Gyeongbug, Korea, which were diagnosed on the ground of clinical and pathological findings with the following results. 1. One hundred and forty weanlings out of 200 ones died suddenly without noticiable signs during the period of 15 days. All of the dead pigs showed formy, blood-tinged discharge from the nose and mouth. 2. Main clinical findings observed from 60 alive pigs from group consisted of fever, cyanosis severe degree of dyspnea and pleuritic friction rub. 3. On hematological observation for typical 5 cases leukocytes showed marked degenerative left shift with leukopenia (10500-13070/cmm), neutropenia (7-13%) and increase in the number of band neutrophils (6-27%). 4. The most prominent and constant pathological changes observed at necropsy for dead or alive pigs consisted of fibrinous pleurisy with partial adhesion, overlying of the pulmonary surface with fibrinous menbrane and necrotic pneumonic lesions with marked edema and congestion of lung parenchyma. 5. From these results the outbreak was considered to be typical porcine pleuropneumonia, although no bacteriological isolation was attempted.