영상신호의 상관관계를 이용한 CORDIC 기반의 DCT 설계

정현욱,김진상,조원경 경희-다반 ASIC 설계교육센터 2002 경희-다반 ASIC센터 논문집 Vol.3 No.-

We propose a novel low-power discrete cosine transform (DCT) architecture based on CORDIC processors. The CORDIC-based DCT algorithm is a good candidate for high performance applications because of its simple arithmetic operation. The proposed algorithm reduces conventional CORDIC-based DCT computation by exploiting the spatial correlation of image data. The proposed architecture can be used for the low-power applications like multimedia portable electronic devices.

酸棗仁이 CT105에 의한 신경세포 상해 및 白鼠의 기억에 미치는 영향

정정욱,박창국,박치상,이소연,윤현덕,신오철 대한본초학회 2005 大韓本草學會誌 Vol.20 No.1

Objective: This study was designed to research whether demonstrate neuroprotective and memory enhancing effects of Z1BU, suggesting its beneficial actions for the treatment of AD. Methods: The present study investigated effects of the dichloromethane extract of Semen Zizyphi Spinosae(ZIBU) on neurotoxicity and reactive oxygen species(ROS) and nitric oxide(NO) formation in PC 12 cell line overexpressed with carboxyl-terminal 105 amino acid peptide fragment of amyloid precursor protein(CT105). In addition, the present study evaluated its radical scavenging activity and effects on acetylcholinesterase(AChE) activity. Furthermore, effects on neuronal loss in CAl area and cognitive deficits induced by scopolamine treatment were also evaluated in rats. Result: we found in this study that ZIBU significantly inhibited apoptotic neuronal death induced by CT105 overexpression in PC12 cells, with the IC_(50) value of 23 ㎍/ml. Based on phase-contrast and fluorescence microscopic examinations, ZIBU reversed morphological changes of CT105-expressed PC-12 cells. It was also found that Z1BU significantly induced neurite outgrowth and inhibited formation of ROS and NO.Z1BU scavenged DPPH radicals and inhibited AChE activity. Furthermore, it attenuated memory impairment induced by the injection of scopolamine in rats, based on passive avoidance test. Crystal violet staining of rat brain slices exhibited increase in the viability of pyramidal neurons in hippocampal CAI area. Conclusion: these results demonstrate neuroprotective and memory enhancing effects of ZIBU, suggesting its beneficial actions for the treatment of AD.

의미 분석 단계에서의 정보 흐름 제어

조현욱,김명수,정은환,유재휘,윤병주 명지대학교 공학기술연구소 1986 공학기술연구소 논문집 Vol.1 No.-

One of protection methods for computer internal data is to pursue data flow in program and to control its flow. In this thesis, we propose a mechanism which guarantees secure information flow in a program. By investigating security classes of all the variables in a statement and judging necessary condition for secure information flow, proposed model descriminates the program whether it is secure or not. Out model can be implemnted at language translation time, particularly semantic analysis phase, by pursuing security class transfer of each statement.

全蝎 抽出物의 抗癲癎效果에 關한 硏究

신현철,윤철호,김종대,정지천,신억섭,허근 한국한의학연구원 1997 한국한의학연구원논문집 Vol.3 No.1

In convulsion state by PTZ in rat, anticonvulsive effect and some γ-aminobutyric acid (GABA)-related mechanisms of Bythus extract in brain was experimented. It was ingibited GABA-T activity, lipid peroxide generation and xanthine oxidase activity as scheduled administration in vitro and vivo. And the content of brain gutathione was increased as scheduled administration in rat. In convulsion state by PTZ of previously managed rat by Buthus extract, onset eime and duration were non-specific changes but recovery time and severity was remarkably reduced. In conclusion speculated that Buthus extract inhibits convulsion by control of GABA content in brain.

암반굴착에 따른 발파진동과 브레이커진동의 특성에 관한 연구

임한욱,박현성 江原大學校 産業技術硏究所 2002 産業技術硏究 Vol.22 No.A

The blast works for open cuts and underground constructions near urban areas have recently increased complaint of ground vibration, air blast and fly rock. In order to reduce these problems, it is necessary to develop more cautious blasting, or non-blast excavation methods by mechanical power. For these breaker workings instead of blast are sometimes adopted. To compare the characteristics of blast vibration with breaker vibration, the level, range of frequency and spectrum amplifications of each vibration were studied.

외과적 보조의 급속상악확장술 : 치험 5예 REPORT OF 5 CASES

박충열,이용욱,송종운,김영운,박홍주,오희균,유선열,이기현,황현식 대한악안면성형재건외과학회 2002 Maxillofacial Plastic Reconstructive Surgery Vol.24 No.1

Five adults (3 cases of bilateral posterior crossbite, 2 cases of unilateral posterior crossbite) with intermaxillary discrepancy of over 5㎜ due to maxillary transverse deficiency were treated by surgically assisted rapid maxillary expansion (SARME). Bilateral maxillary horizontal osteotomies, osteotomies of pterygomaxillary junction and anterior lateral nasal wall, ans anterior palatal osteotomy were performed in 4 cases, and unilateral osteotomies in 1case, followed by palatal expansion with tooth-borne orthopedic applicance. No significant complication was observed. The mean palatal expansion was 7.2㎜ (5.8∼10.0㎜) in the maxillary first molar region. During the mean follow-up period of 4 years (5 months∼8 years 7 months), no recurrence of crossbite was observed in all cases. The SARME seemed to be a simple, stable, and reliable procedure for achieving a permanent increase of over 5㎜ in skeletal maxillary transverse width of adults.

被動的 學習者 假說의 學習障碍 教育에의 適用 可能性

UK Hyeon Baek(白旭鉉) 공주대학교 교육연구소 1993 교육연구 Vol.9 No.-

This study examined the validity of the inactive learner hypothesis and the possibility of its application to LD children education. Learning disabled children have often been characterized as inactive or passive problem solver as compared to their non-learning disabled peers. Many researchers interested in the hypothesis have studied on the domain of problem solving because it enables an examination of children’s learning process. As a result, learning disabled children are ineffective in planning, problem representation, self-monitoring, and approaching the task in an organized fashion. That is, learning disabled children have been descrived as “inactive” or “other regulated” learner. Recently, Short and Weissberg-Benchell(l989) explained the significance of cognitive, metacognitive, and motivational factors for successful learning in their Triple Alliance Model. According to this model, skilled learner must achieve a delicate balance among these three process. Inactive learner form faulty alliances among three process. This model offers diers direct support for the inactive learner hypothesis. Thus, the researches related with this model were investigated. Also the effects of the intervention techniques promoting active self-regulated learning disabled children applied to practical education were examined. As results of examination of the literature on the inactive learner hypothesis, the following conclusion could be made. The hypothesis held theoretical and educational appeal in that it was an all-inclusive theory, but now appears in hindsight to be plagued with the common problems of the field. These problems include imprecision in sample definition, measurement, and causality. Also the evidence clearly exist that the hypothesis only applicable to a subgroup of the learning disabled population. The future of the hypothesis as a viable descriptive and experimental tool lies in our ability to classify reliable subgroups of inactive learner and to pinpoint the underlying causes for this inactivity.

IMM EKF based Sensor Fusion for Vehicle Positioning Under Various Road Surface Conditions

Hyeon Uk Heo,Dae Jung Kim,Chung Choo Chung 제어로봇시스템학회 2020 제어로봇시스템학회 국제학술대회 논문집 Vol.2020 No.10

In this paper, we propose an estimation of the accurate vehicle position using Interacting Multiple Model Extended Kalman Filter (IMM EKF) when road surface varies. Since the vehicle has different cornering stiffness as the road surface varies, it is difficult to accurately estimate the position of the vehicle. To resolve this problem, we present the IMM EKF considering each model of different roads to improve the estimation performance. From the numerical simulation using MATLAB/CARSIM, we observed that the performance of the proposed algorithm improves vehicle positioning performance.

幼兒 運動技術發達의 測定과 運動活動 프로그램

Uk Hyeon Baek(白旭鉉) 공주대학교 교육연구소 1989 교육연구 Vol.6 No.-

As children grow older, they gradually acquire a broad repertoire of motor skills. Some skills emerge more or less spontaneously and later perfected with practice. These kills, emerging perhaps through mimicry, but without the need for specific tuition, may be termed endogenous skills. Other skills tend to emerge in response to demand by an external agent such as a parent, teacher or another child. Such skills, which come to be superimposed on the basic repertoire, may be termed exogenous. Motor skill development is an extremely important issue in the overall development of the child, for often a failure to manifest appropriate motor behavior is a signal that cognitive function may be impaired. This article provided a brief theoretical background to motor skill development in children, and also provided an update on the approach to the assessment and program of motor activity. Much of the assessment of early child development focuses on the motor area, since (1) motor abilities are more easily and reliably observed at a very early age than are cognitive abilities ; and (2) motor development is held by many to be the foundation of later cognitive development. In this article, four major approaches taken in motor skill development assessment were reviewed and some of the strengths and limitations associated with each approach were discussed. First is the descriptive or product oriented approach, in which a group of motor tasks is selected and each child’s performance is compared with the average performance of children in his or her age group. The second approach, temed process oriented or diagnostic, consists of evaluating tasks which are indicative of an underlying process of motor performance based on theoretical postulates. In the third termed process/descriptive approach, children are observed in activities such as running, throwing, and catching, and their performance is judged on the basic of a qualitative analysis of their movement pattern. In reflex testing, the fourth approach, children are evaluated on the bases of the appearance and/or inhibition of certain reflex movements according to age level. Programming motor activities for the young child may be divided into three district approaches : the traditional approach, the movement education approach, and the perceptual motor approach. programs and activities to develop the motor abilities of children during their formative years are integral to the process of normal development. Programs of motor activity for the young child should begin with emphasis on informality and self-discovery, to allow children to appreciate their movement capabilities. For young children, informal play setting with play equipment that encourages a variety of large muscle movement are important. Developing children must be able to appreciate the scope and potential of their abilities before the refinements and constraints of formal motor skills are placed upon them. As strength, motor skills, and flexibility develop, young children will participated actively in the more formal motor skill activities.

兒童의 內在的 動機開發과 教育

Uk Hyeon Baek(白旭鉉) 공주대학교 교육연구소 1988 교육연구 Vol.5 No.-

How do children become curious, learn to master their environment, and perceive that they are effective and competent? Theories of the development of intrinsic motivation can be grouped into three categories-cognitive, competence, and attribution theories-since each emphasizes different aspects of intrinsic motivation. Cognitive theorists assert that intrinsic motivation is produced when children encounter experiences discrepant from their current cognitive level and they attempt to understand the new experiences. Such behaviors as curiosity, exploration, investigation, and manipulation may be indicators of children s attempts to reduce this cognitive discrepancy (conceptual conflict). Competence theorists focus upon children s mastery of their environment as the core of intrinsic motivation. Children seek to interact effectively with their environment. Through mastery the child experiences a feeling of efficacy, which is an intrinsic motivation. The indicators of competence motivation are selectivity, persistence, and exploration. Attribution theory deals with how children perceive the cause of their behavior. When children attribute the cause of their behavior, to their own efforts, competence, or self-selection of goals, intrinsic motivation is likely to be enhanced. Across theories, children are not viewed as being either high or low in intrinsic motivation, but rather their motivation varies depending on specific content areas and conditions influencing cognitive conflicts, competence, or attribution. While these three broad divisions have provided different perspectives for research, there may be interrelationships between cognitive, competence, and attribution intrinsic motivation, but may allow for the child s experience of mastery and competence through developing understanding of unfamiliar materials. People seek out incongruity to experience competence through resolution of cognitive conflict. Further, if the environment provides feedback to children about their competence, both mastery and attributions of mastery should be enhanced. Childhood educators should therefore attempt to develop all three aspects of intrinsic motivation. Reviewing the research concerned with the intrinsic motivation development, the researcher makes the following conclusions. All adults and teachers who work with children should be aware of the importance of (1) providing a novel, varied, and challenging home environment from birth. (2) providing experiences in which children have a noticeable effect on the environment. (3) providing an environment that is responsive to the child s actions. (4) responding positively to children s questions, and encouraging children to find their own solutions to problems. (5) rewarding children with praise which gives them a feeling of competence. (6) providing children with opportunity to investigate individual areas of interest and curiosity. (7) giving children choices about their preferred activities. (8) establishing an atmosphere of trust so that children are not anxious about asking questions or making mistakes.