• 한국항공우주학회지
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• 제45권8호
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• pp.671-677
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• 2017

본 논문은 관성항법시스템(Inertial Navigation System)과 비전 센서(Vision Sensor)를 활용한 통합 항법시스템의 성능 향상을 위한 INS/멀티비전 통합항법 시스템을 제시하였다. 기존의 단일 센서나 스테레오 비전(Stereo vision)을 활용한 경우 측정되는 랜드마크의 수가 적을 경우 필터가 발산하는 문제가 발생할 수 있다. 이러한 문제를 해결하기 위해 본 논문에서는 3개의 비전 센서를 동체를 기준으로 $0^{\circ}$, $120^{\circ}$, $-120^{\circ}$으로 설치하여 단일 센서로 사용되는 경우보다 성능이 향상됨을 수치 시뮬레이션을 통하여 검증하였다.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.377.3-378
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• 2002

Eight compounds were isolated from the MeOH extracts of Erythrina senegalensis for HIV-1 protease inhibitors. Their structures were elucidated as eight isoflavonoids by spectroscopic analysis. These compounds showed dose dependent inhibitory activities on HIV-l protease with $IC_{50}$ values from 0.5 to 30.0 ${\mu}$M. (omitted)

• Wind and Structures
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• 제20권2호
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• pp.315-326
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• 2015

To overcome the drawbacks of the traditional contact-type sensor for structural displacement measurement, the vision-based technology with the aid of the digital image processing algorithm has received increasing concerns from the community of structural health monitoring (SHM). The advanced vision-based system has been widely used to measure the structural displacement of civil engineering structures due to its overwhelming merits of non-contact, long-distance, and high-resolution. However, seldom currently-available vision-based systems are capable of realizing the synchronous structural displacement measurement for multiple points on the investigated structure. In this paper, the method for vision-based multi-point structural displacement measurement is presented. A series of moving loading experiments on a scale arch bridge model are carried out to validate the accuracy and reliability of the vision-based system for multi-point structural displacement measurement. The structural displacements of five points on the bridge deck are measured by the vision-based system and compared with those obtained by the linear variable differential transformer (LVDT). The comparative study demonstrates that the vision-based system is deemed to be an effective and reliable means for multi-point structural displacement measurement.

• 한국생산제조학회지
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• 제8권6호
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• pp.26-34
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• 1999

This study shows an alternative method for the determination of object's position, based on a computer vision method. This approach develops the vision system model to define the reciprocal relationship between the 3-D real space and 2-D image plane. The developed model involves the bilinear six-view parameters, which is estimated using the relationship between the camera space location and real coordinates of known position. Based on estimated parameters in independent cameras, the position of unknown object is accomplished using a sequential estimation scheme that permits data of unknown points in each of the 2-D image plane of cameras. This vision control methods the robust and reliable, which overcomes the difficulties of the conventional research such as precise calibration of the vision sensor, exact kinematic modeling of the robot, and correct knowledge of the relative positions and orientation of the robot and CCD camera. Finally, the developed vision control method is tested experimentally by performing determination of object position in the space using computer vision system. These results show the presented method is precise and compatible.

• 한국기계가공학회지
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• 제17권5호
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• pp.161-172
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• 2018

This paper proposed the robot vision control method to track a moving rigid body target using the vision system model that can actively control camera parameters even if the relative position between the camera and the robot and the focal length and posture of the camera change. The proposed robotic vision control scheme uses a batch method that uses all the vision data acquired from each moving point of the robot. To process all acquired data, this robot vision control scheme is divided into two cases. One is to give an equal weight for all acquired data, the other is to give weighting for the recent data acquired near the target. Finally, using the two proposed robot vision control schemes, experiments were performed to estimate the positions of a moving rigid body target whose spatial positions are unknown but only the vision data values are known. The efficiency of each control scheme is evaluated by comparing the accuracy through the experimental results of each control scheme.

• 한국조경학회지
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• 제44권1호
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• pp.80-92
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• 2016

본 연구는 경관계획 내용 중 경관 미래상의 작성 현황을 분석하여 문제점을 도출하고 이에 대한 향후 개선방안을 제안함으로써 향후 지자체 경관향상을 위한 실용적인 경관계획을 위한 기초자료를 제공하는 것을 목적으로 하였다. 이를 위해 본 연구는 경관 미래상을 작성하고 있는 실무자 대상 인터뷰를 통하여 미래상 작성 방법을 조사하였고, 수도권 32개 지자체에 수립된 경관계획을 조사하여 경관 미래상의 작성 형식과 내용을 분석하였다. 그리고 경관 미래상과 유사한 목적과 형태로 작성되고 있는 도시계획 상의 도시 미래상과 지자체 비전을 담고 있는 도시 슬로건을 함께 조사하여 경관 미래상과 작성 경향 및 내용을 비교 분석함으로써 경관 미래상의 작성 방향 및 시사점을 도출하고자 하였다. 연구결과를 요약하면 다음과 같다. 경관 미래상은 주로 경관계획 수립을 위해 기본구상 작성에 앞서 조사한 경관자원현황과 관련 상위 계획의 미래상 및 목표를 참조하는 것으로 나타났다. 이는 경관계획의 세부 내용 간 일치성과 관련 계획 간의 정합성을 높이는 방법이 될 수 있으므로 이러한 방법을 경관계획 수립 지침에 구체적으로 언급되는 것이 바람직하다. 또한 현재 경관 미래상은 도시 슬로건과 유사하게 구호 형태로 작성되고 있으나, 경관 미래상은 홍보의 수단이나 응용되어 활용되지 않으므로 일괄적으로 작성되고 있는 구호형 경관 미래상에 대한 검토가 필요하다. 그리고 경관 미래상과 도시 미래상, 도시 슬로건의 내용적 연관성을 분석한 결과 경관 미래상은 도시 슬로건에 비해 도시 미래상과 내용적 일치성이 높은 것으로 나타났으며, 이는 상위계획과의 정합성을 고려하여 작성하고 있다는 측면에서 긍정적 분석 결과라 판단된다. 다만 향후 이러한 정합성이 유지 및 증진될 수 있도록 경관계획수립지침에서 경관 미래상 작성과 관련한 구체적인 방법을 제시할 필요가 있다.

• 한국임상보건과학회지
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• 제3권3호
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• pp.399-408
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• 2015

Objective. There were two objectives of the study, first was to identify the barriers as perceived by the patients and providers to access the low vision services and second was to identify the challenges faced by the main providers. Study design. Structured questionnaire based interviews of patients and providers Methodology. To find out the barriers to access of low vision services, the interviews based on structured questionnaire were conducted for two patient groups. The first group consisted of 97 visually impaired individuals attending the department of low vision services at Al-Shifa Trust Eye Hospital Rawalpindi while the second group included 56 visually impaired individuals attending the four rehabilitation centers/schools for the blind in Rawalpindi/Islamabad. To identify the barriers as perceived by the main providers of low vision services and challenges faced by them the interviews based on structured questionnaire were conducted for 19 low vision service providers. Results. From patients point of view, major barrier to low vision services identified was inability to visit hospital /rehabilitation center alone - 29.8% in hospital group and 33.9% in rehabilitation centers group, while the lack of social support, lack of family support, cost of travelling, long distance, afford ability, hesitation in using devices and lack of satisfaction were other important barriers identified. From providers' point of view, major barrier to uptake of services was the need for repeated follow-ups. Optometrists were the main provider of low vision services contributing to 47.4% of the providers. The major challenge faced by the providers was motivation of patients to use low vision devices. Conclusion. The major barrier to low vision services according to the patients is inability to visit the hospital alone, while according to providers, it is the need for repeated follow up which proves major barrier towards uptake of services. The motivation is the major challenge faced by providers, majority of which are optometrists.

• 한국안광학회지
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• 제13권4호
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• pp.109-114
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• 2008

목적: 본 연구는 색각검사법의 반복측정에 따른 결과의 재현성을 평가하기 위해 진행하였다. 방법: 연구 대상자는 선천성 색각이상을 가지고 있지 않은 일개 대학교 안경광학과 학생 30명이었다. 색각이상검사 종류는 한식색각검사와 Hans 15 hue 검사 그리고 Lanthony D 15 hue 검사를 선택하였고, 3명의 검사자를 비교하기 위한 검사에서는 이시하라검사도 추가하였다. 결과: 가성동색표에서는 모두 정상으로 분류되어졌으나, 색분별법에서는 1명이 약한청황색각이상을 보였다. 가성동색표는 3번의 측정 및 검사자간 결과값이 일치하였으며, 색분별법 반복 측정에서 경미한 오류들의 차이가 나타났다. 그러나 실제 색각이상자의 분류에 있어서는 반복측정에 따른 결과값이 차이는 나타나지 않았다. 결론: 각 검사자는 비교적 간단한 색각검사라도 좀더 숙련된 기술로 피험자를 대하는 것이 필요하다. 피험 자 역시 세 번의 측정으로 인한 경험에 의존하여 색각검사를 하기보다는 매 검사는 신중을 기해야 함이 요구되어 진다. 선별검사에서는 두 가지 검사의 병행이 요구되어진다.

• 공학교육연구
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• 제21권6호
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• pp.99-107
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• 2018

The purpose of this study is to establish and propose educational vision of chemical engineering field in order to search for academic identity and future education direction in chemical engineering field. In order to achieve this research purpose, we investigate the literature and data on the vision, educational goals, and curriculum of the department of chemical engineering in domestic and foreign universities. We also analyze the SWOT of internal and external environmental factors respectively. The validity of the proposal was verified through delphi survey with delphi panels and the vision was developed by revising and improving upon the opinions of professionals. The vision is comprised of the value and mission of learning, the educational purpose, and the educational goal. The first stage is value and mission of chemical engineering. The educational purposes and the educational goals are divided into 'Department of Chemical Engineering' and 'Department of Chemical and Biological Engineering'. The application of the educational vision of chemical engineering field is as follows. First, we expect that the vision to be a valuable, philosophical, and theoretical basis for establishing educational objectives and goals in the field of chemical engineering. Hopefully, it will be used as a general education goal for the top-level education. Second, we hope that the vision will be used to develop customized vision, customized educational purpose, and educational goals that reflect the characteristics of region, departments, graduates, and educational needs in the field of chemical engineering. Finally, we hope that these results will be the starting point to discuss the educational vision in the department of chemical engineering.

• 대한임베디드공학회논문지
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• 제18권3호
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• pp.89-100
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• 2023

Recently, on-device artificial intelligence (AI) solutions using mobile devices and embedded edge devices have emerged in various fields, such as computer vision, to address network traffic burdens, low-energy operations, and security problems. Although vision transformer deep learning models have outperformed conventional convolutional neural network (CNN) models in computer vision, they require more computations and parameters than CNN models. Thus, they are not directly applicable to embedded edge devices with limited hardware resources. Many researchers have proposed various model compression methods or lightweight architectures for vision transformers; however, there are only a few studies evaluating the effects of model compression techniques of vision transformers on performance. Regarding this problem, this paper presents a performance evaluation of vision transformers on embedded platforms. We investigated the behaviors of three vision transformers: DeiT, LeViT, and MobileViT. Each model performance was evaluated by accuracy and inference time on edge devices using the ImageNet dataset. We assessed the effects of the quantization method applied to the models on latency enhancement and accuracy degradation by profiling the proportion of response time occupied by major operations. In addition, we evaluated the performance of each model on GPU and EdgeTPU-based edge devices. In our experimental results, LeViT showed the best performance in CPU-based edge devices, and DeiT-small showed the highest performance improvement in GPU-based edge devices. In addition, only MobileViT models showed performance improvement on EdgeTPU. Summarizing the analysis results through profiling, the degree of performance improvement of each vision transformer model was highly dependent on the proportion of parts that could be optimized in the target edge device. In summary, to apply vision transformers to on-device AI solutions, either proper operation composition and optimizations specific to target edge devices must be considered.