서베일런스 시스템에서 HMM을 이용한 실시간 헤드 움직임 검출

박양재 한국정보기술학회 2014 한국정보기술학회논문지 Vol. No.

This paper addresses a technique of detecting a head nod and shake. The proposed system is composed of head tracking and head motion decision. The head tracking step is divided into head detection, head location. We propose a method of fast frontal head detection method. We use motion segmentation algorithm that makes use of differencing to detect moving people’s head. The novelty of this paper comes from the differencing in real time input images, preprocessing to remove noises (morphological operator and so on), detecting edge lines and restoration, finding the head area and cutting the head candidate. It is performed at the region close to a pair of heads for real-time head tracking. After head tracking, the coordinates of the detected head are transformed into the normalized vector of the x-coordinate and the y-coordinate. Head nod and shake detector using three HMMs. Head nod and shake can be detected by three HMMs those are adapted by a directional vector. The directional vector represents the direction of head movement. The vector is HMMs to determine neutral as well as head nod and head shake. Experimental results show a higher degree of 5% than the conventional method proposed a method of recognition performance. 본 논문은 머리의 끄덕임과 흔들림의 탐지 기술에 대하여 설명한다. 제안하는 시스템은 머리 움직임의 추적으로 구성되며 머리를 탐지하기 위하여 차영상 방법을 이용하는 움직임 구역화 알고리즘을 사용한다. 제안하는 방법의 실효성은 실시간 입력 영상에서 차영상을 이용하는 것과 잡음 영상을 제거(모폴로지 연산 등)하기 위한 전처리 과정과 윤곽선의 탐지와 복원, 머리 영역의 탐지와 머리 후보의 획득 과정이다. 머리의 끄덕임과 움직임을 탐지하기 위하여 세가지 HMM을 이용한다. 머리 끄덕임과 움직임은 방향 벡터에 의하여 조정 되어진 세 가지 HMM에 의하여 탐지될 수 있다. 그 벡터는 머리 끄덕임과 움직임뿐만 아니라 고정을 결정하는 HMM 이다. 실험 결과에서 보면 제안하는 방법으로써 머리의 움직임을 탐지하였을 때 기존의 방법보다 5% 정도 더 높은 인식 성능을 보여준다.

Analysis on perceptual sensitivity to head-related impulse responses in the median plane

황성목,박영진,박윤식 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.12

This study deals with the perceptual sensitivity to Head-Related Impulse Responses (HRIRs) in the median plane based on a series of subjective listening tests using a pair of headphones. First, the non-individualized HRIRs were modeled from 12 principal components (PCs) extracted from Principal Components Analysis (PCA) of the CIPIC HRTF database. The Just Noticeable Difference (JND) in weight of PCs (PCWs) at each elevation was estimated. It was not observed the common elevation-dependent tendency or PCW-dependent tendency of JND in PCWs across the five subjects who participated in the tests, and the inter-subject variation of JND in PCWs was large. The JND in HRIRs can be estimated indirectly from the JND in PCWs because the HRIRs can be represented by a linear summation of the PCs weighted by PCWs. The common elevation-dependent tendency of JND in Directional Impulse Responses (DIRs), which are the mean-subtracted HRIRs, across the five subjects can be found. The change in PCWs does not seem to contribute to our perception of sound source characteristics; however, the resulting change in HRIRs due to the change in PCWs seems to contribute. The subjects showed larger JND in DIRs in the frontal region than in the rear region. This means that our perception of sound source characteristics is more sensitive for frontal sources than rear sources.

Head-Mounted Display(HMD) 시청 환경에서 양안 밝기 차이에 따른 피로도 - 감각성 우세안을 중심으로

김효선(Kim, Hyosun),서영준(Seo, Young-Jun),조성찬(Jo, Sung-Chan) 한국색채학회 2021 한국색채학회 논문집 Vol.35 No.2

Since both stereoscopic devices and Head-Mounted Displays (HMDs) use the diplopic projection which the separate images are presented on the left- and right-eye, it is revealed that the difference of binocular images caused the visual fatigue. In addition, the interocular imbalance, especially the sensory eye dominance, can also be connected with the visual fatigue by the photometric asymmetry of the binocular images. The purpose of this study is to investigate how the brightness asymmetry between the binocular images affect the visual fatigue and to explore how the sensory dominance affects visual fatigue. Wearing HMDs, participants were asked to view binocular images: one had 100% brightness, the other 50~90% brightness. They evaluated the visual fatigue on a 7-point Likert scale. As the result, an increase in brightness asymmetry between viewers’ left-eye and right-eye increased the visual fatigue scores. The relationship between the sensory dominance and the visual fatigue by the brightness asymmetry was different depending on the type of image. The visual fatigue increased as the brightness of images, which entering to the sensory dominant eye, decreased in the case of the black-and-white images. On the contrary, the visual fatigue was not changed in the case of color images in the same condition. This meant that the brightness contrast and color contrast had different effect on the visual fatigue. Overall, we suggest that the brightness asymmetry of less than 30% is suitable for a comfortable and positive viewing experience.

중증 뇌손상 환자에서 뇌동정맥 산소함유량차이와 지연성 뇌경색 발생과의 관계

윤승환,조준,문창택,장상근,박형천,박현선,김은영,Youn, Seung-Hwan,Cho, Joon,Moon, Chang-Taek,Chang, Sang-Keun,Park, Hyung-Chun,Park, Hyeon-Seon,Kim, Eun-Young 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.4

Objective : This study was performed to evaluate the relationships among intracranial pressure(ICP), cerebral perfusion pressure(CPP), and cerebral arteriovenous oxygen difference($AVDO_2$) which were used as parameters of adequacy of cerebral blood flow to support cerebral metabolism after severe head injury and also to examine the association between delayed cerebral infarction and outcome. Material and Method : The authors studied the ICP, CPP and $AVDO_2$ before and after treatment on 34 head-injured patients from June 1996 to December 1997 and examined the association with the change of an ICP, CPP and $AVDO_2$ following treatment and the development of delayed cerebral infarction. Sixteen patients underwent craniotomy for hematoma evacuation and eighteen patients received mannitol to decrease ICP. Results : The development of delayed cerebral infarction was demonstrated in 3(42.9%) out of 7 patients in no improvement group and 13(48.1%) out of 27 patients in improvement group with an increased ICP following treatment. Also, the development of delayed cerebral infarction was demonstrated in 8(50%) out of 16 patients in no improvement group and 8(44.4%) out of 18 patients in improvement group with a decreased CPP following treatment. The association with changes of ICP and CPP following treatment and development of delayed cerebral infarction was not statistically significant(p>0.01). However, 11(78.6%) out of 14 patients who demonstrated an increase in $AVDO_2$ and 5(25%) out of 20 patients who demonstrated a decrease in $AVDO_2$ following treatment developed delayed cerebral infarction. No improvement(reduction) in $AVDO_2$ following treatment was significantly associated with the development of delayed cerebral infarction(p<0.01). All of 16 patients with delayed cerebral infarction showed poor prognosis. Conlcusion : The change of $AVDO_2$ rather than those of ICP and CPP was considered more important factor for the development of the delayed cerebral infarction and poor outcome.

머리의 회전 속도와 시선 고정 거리, 머리 회전 방향에 따른 비디오두부충동검사에서의 전정안반사 이득의 변화

송찬일,김영은,차은혜,유명훈,이제연,박홍주 대한이비인후과학회 2015 대한이비인후과학회지 두경부외과학 Vol.58 No.8

Background and Objectives The conventional instrument for video head impulse test (vHIT) records the movement of the right eye only. The aim of this study was to evaluate the changes in the gain of vHIT results qdue to different directions of head rotation directons at different target distances and rotation speeds. Subjects and Method Horizontal head impulse was recorded by vHIT in 20 normal subjects. vestibulo-ocular reflex (VOR) gains to the right and left directions were compared at different test conditions. Two different impulses with low (50-150 deg/sec) and high (200-300 deg/sec) peak-head-velocities were tested and the subjects were also instructed to fixate a laser dot on a screen at different distances of 60, 100, and 200 cm. Eye movements were recorded on the right eye. Results Regardless of the target distances and peak-head-velocities, the VOR gains to the rightward head rotation were significantly greater than those to the leftward head rotation. In more than 85% of normal subjects, vHIT gain to the rightward head rotation was greater than that to the leftward head rotation. Mean gain asymmetries were 2.16-3.33% and the mean interaural vHIT gain differences were 0.04-0.07. Conclusion Regardless of the target distances and peak-head-velocities, the VOR gains to the rightward head rotation were significantly greater than those to the leftward head rotation. Directional asymmetry of VOR gain should be considered when interpreting vHIT results in patients with vestibular disorders.

어린이집 주임교사의 변혁적 리더십에 대한 인식차이와 직무만족도에 관한 연구

모아라 ( A Ra Mo ) 대한아동복지학회 2012 아동복지연구 Vol.10 No.1

본 연구에서는 어린이집 주임교사의 경력에 따른 변혁적 리더십에 대한 인식차이와 그에 따라 직무만족도에 미치는 영향에 대해 알아보고자 하였다. 연구 대상은 서울ㆍ경기 및 기타지역 어린이집에서 근무하고 있는 주임교사 180명을 대상으로 하였으며 어린이집 주임교사의 경력에 따른 인식차이를 검증하기 위해 변혁적 리더십의 평가척도를 본 연구에 맞게 수정ㆍ보완하여 사용 하였고, 어린이집 교사의 직무만족도를 알아보기 위해서는 어린이집 직무만족도 측정도구(ECJSS) 중 직무만족도를 우리나라 상황에 맞게 수정, 보완한 구성요인을 사용하였다. 연구결과, 경력에 따라 변혁적 리더십 전체 하위 요인에 대해 지각 차이를 보이며, 주임교사의 변혁적 리더십이 직무만족도 전체와 그 하위 요인별로도 매우 높은 상관관계를 보임을 알 수 있었다. 또한 변혁적 리더십이 직무만족도에 미치는 영향에 대해서는 동료 교사와의 관계, 원장과의 관계, 직무자체, 근무환경, 보수와 승진 기회에 모두 유의미한 영향력이 있음을 알 수 있었다. 따라서 주임교사의 역할을 할 수 있도록 변혁적 리더십과 같은 리더십 프로그램이 필요하다. 마지막으로 이는 서울 및 경기 지역에 국한된 연구이므로 일반화하기 어려운바 전국 단위의 연구를 통해 자세한 연구 조사가 필요할 것으로 생각하는 바이다. The purpose of this study was to examine differences in recognition of transformational leadership according to head teacher`s careers, and to evaluate the extent of its impact on job satisfaction. The subjects of this study were 60 head teachers who had careers of 1 to 3 years, 60 head teachers who had careers of 3 to 5 years, and 60 head teachers who had careers of over 5 years. All of the head teachers worked for child care centers located in Seoul, Gyeonggi-do, and other areas. To obtain verification of differences in recognition of transformational leadership according to head teacher`s careers, a modified version of the Transformational Leadership Scale was used. In order to analyze the job satisfaction of head teachers, the job satisfaction factor from the Early Childhood Job Satisfaction Survey (ECJSS) was modified and used. The results of this study indicated that differences in recognition displayed all sub-factors of transformational leadership, and the transformational leadership of head teachers was very highly correlated with all sub-factors of job satisfaction according to their careers. Furthermore, it was revealed that transformational leadership significantly affected the subfactors of job satisfaction such as relationships with fellow teachers, relationship with principal, teacher`s duty, working conditions, payment and opportunity for promotion. According to the results of the study, I suggest that transformational leadership programs for head teachers should be guaranteed. However, as this study was mostly limited to areas such as Seoul and Gyeonggi-do, its results cannot be generalized. Therefore, it is necessary to conduct further studies on a nationwide level.

Structural and Functional Features of Written Code-Switching by Korean Speakers of English

신창원 국제언어인문학회 2008 인문언어 Vol.10 No.-

This study investigated the alternate use of English by Korean speakers of English in informal Korean written texts to see (1) in what situations and for what purposes Korean adult speakers of English living in the United States, code-switch into English, in the context of their own personal writing in Korean, and (2) what are the linguistic or structural features of the alternate language forms that they might produce. For this study, data were collected from 4 Korean female adults living in a mid-sized southern city with different goals for residency in the United States. Personal documents and unstructured interview were employed as a data collection method. The results showed that the structural features of the written code-switching might be explained by the typological difference between Korean and English with respect to the head position in given phrases, in that the head position ‘head-initial’ or ‘head-final’ has been considered to be a crucial factor determining the basic word order of a given language. On the other hand, it was found that the participants' perceived reason for using English content words in the Korean informal texts or adopting English word order might be for bridging the gap between their native language and their American life. It was suggested that the functional feature of the alternate use of English and Korean might be followed from that fact that memos on the datebooks should be efficient and economical, i.e. easily recognized and quickly produced. This study investigated the alternate use of English by Korean speakers of English in informal Korean written texts to see (1) in what situations and for what purposes Korean adult speakers of English living in the United States, code-switch into English, in the context of their own personal writing in Korean, and (2) what are the linguistic or structural features of the alternate language forms that they might produce. For this study, data were collected from 4 Korean female adults living in a mid-sized southern city with different goals for residency in the United States. Personal documents and unstructured interview were employed as a data collection method. The results showed that the structural features of the written code-switching might be explained by the typological difference between Korean and English with respect to the head position in given phrases, in that the head position ‘head-initial’ or ‘head-final’ has been considered to be a crucial factor determining the basic word order of a given language. On the other hand, it was found that the participants' perceived reason for using English content words in the Korean informal texts or adopting English word order might be for bridging the gap between their native language and their American life. It was suggested that the functional feature of the alternate use of English and Korean might be followed from that fact that memos on the datebooks should be efficient and economical, i.e. easily recognized and quickly produced.

목 폄 시 탄력성 테이프의 신장력 차이가 전방머리자세 증후군의 근수축 개시시간에 미치는 영향

윤정규 대한고유수용성신경근촉진법학회 2022 PNF and Movement Vol.20 No.3

Purpose: This study aimed to identify the effect of varying the expansibility of elastic tape on the onset time of muscle contraction during neck extension for forward head posture syndrome. Methods: Forty-five young adults with forward head posture syndrome volunteered to participate and were randomly assigned to one of three groups according to the expansibility of the elastic tape (25%, 50%, 75%). The onset time of muscle contraction for the neck extensor during neck extension was measured using an electromyographic system (Free EMG, BTS, Italy). Multivariate analysis of variance was employed to determine the effect of different expansibilities of elastic tape on the onset time of muscle contraction during neck extension for forward head posture syndrome. When there was a statistically significant difference by MANOVA, Scheffe was used as a post-hoc test. The level of significance was set at α=0.05. Results: In the comparison of the onset time of muscle contraction of varying elastic tape expansibilities and measurement times, there was a significant difference between the groups (Lt. UT, Lt. SCM, Rt. SCM) (p < 0.05), but there was no significant difference in the interaction between the measurement time and the group, between the measurement time (p > 0.05). Conclusion: In the neck extension, 75% of the tape extensibility in the Lt. UT and both SCM shortened the muscle contraction onset time.

골반변위와 대퇴골두 높이차이에 대한 상관성 비교

박민정(Park min-jung),이경윤(Lee kyung-yun),서진우(Seo jin-woo),박쾌환(Park kwae-hwan) 척추신경추나의학회 2004 대한추나의학회지 Vol.5 No.1

Objectives : To investigate contributing degree of other factors except pelvic tilting to F.L.L.D by analizing with Gonstead technique on the correlation between femur head height discrepancy on the standing pelvic AP view and F.L.L.D caused by pelvic tilting. Method : We analysed standing pelvis AP X-ray of 70 patients who had visited at the department of acupunture and moxibustion in Conmaul oriental medical hospital, during May, 1st, 2004 - July, 30th, 2004, with low back pain or lower extremity pain. We excluded the person with any past history of polio, genetic defect, malunited fracture, growth plate injury, infection and overgrowth attributable to hemangioma, or arteriovenous fistula. Results & Conclusion : The functional leg length discrepancy caused by pelvic tilting and femur head height difference had no statistical difference(p=0.132) but poorly correlated(Pearson γ=0.05). In the 94.28% of subjects, the femur head height difference wasn t in accord with F.L.L.D. caused by pelvic tilting. In 47.14% of subjects were expected to have over 3㎜ of leg length discrepancy after pelvic adjustment. The mean of measurement difference between two methods was 3.76±3.12㎜ and the range was 0~11.4㎜. Consequently, we must consider not only functional leg length discrepancy caused by pelvic tilting but also anatomical leg length discrepancy, misalignment of ankle, knee or hip joint etc.

확대머리 철근과 갈고리 철근을 이용한 단차가 있는 휨부재의 겹침이음상세

이규선,진세훈,김승훈 한국구조물진단유지관리공학회 2016 한국구조물진단유지관리공학회 논문집 Vol.20 No.4

This paper focuses on the experimental study for investigating the performance for lap splice of hooked or headed reinforcement in beam with different depths. In the experiment, seven specimens, with its variables as the lap length of headed or hooked bar, the existence of stirrups, etc., was manufactured. Bending test was conducted. Lap strengths by test were compared with the theoretical model based on KCI2012. The result showed that the cracks at failure mode occurred along the axial direction to a headed bar. The initial stiffness and the stiffness after initial crack were similar for all specimens. For HS series specimens without stirrups, a 25% increase in lap length was increased 11.8~18.1% maximum strengths. For HH series specimens without stirrups, a increase in lap length did not affect the maximum strengths because of the pryout failure of headed bar. For HS series specimens, the theoretical lap strengths based on KCI2012 considering the B grade lap and the reduction factor for stirrup were evaluated. They are smaller than the test strengths and can ensure the safety in terms of strength capacity. For HH series specimens, the stirrups in the lap zone are needed to prevent the pryout behaviour of headed bar.