• BMB Reports
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• v.54 no.1
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• pp.59-69
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• 2021

The ability to read, write, and edit genomic information in living organisms can have a profound impact on research, health, economic, and environmental issues. The CRISPR/Cas system, recently discovered as an adaptive immune system in prokaryotes, has revolutionized the ease and throughput of genome editing in mammalian cells and has proved itself indispensable to the engineering of immune cells and identification of novel immune mechanisms. In this review, we summarize the CRISPR/Cas9 system and the history of its discovery and optimization. We then focus on engineering T cells and other types of immune cells, with emphasis on therapeutic applications. Last, we describe the different modifications of Cas9 and their recent applications in the genome-wide screening of immune cells.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2020.11a
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• pp.109-112
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• 2020

사람 재인식을 수행하기 위해서 많은 연구들이 진행되어 좋은 결과들을 보였다 그러나 이 결과들은 라벨이 있는 도메인에서의 지도 학습으로 얻은 결과들이었다. 라벨이 없는 도메인에서의 사람 재인식의 성능은 아직 많이 부족한 상태이다. 사람 재인식을 수행하고자 하는 목표 도메인에 반해 주어진 소스 도메인에서는 라벨이 풍부하다. 지금까지의 논문에서는 소스 도메인에서의 사람 이미지를 목표 도메인의 이미지처럼 만들어서 소스 도메인에서 높은 성능을 보이는 사람 재인식기를 목표 도메인에서도 잘 동작하도록 학습하는 방법들이 주를 이루었다. 하지만 이 방법에서는 소스 도메인의 사람 이미지를 목표 도메인의 이미지와 비슷하게 만들기만하고 사람의 신원에 대한 일관성을 유지시키지는 못하였다. 본 논문에서는 비지도 도메인 적응 사람 재인식을 수행하기 위해 클러스터 일관성(cluster consistency)을 유지하는 기법을 제안한다. 제안한 방법은 사람의 신원에 대한 일관성을 유지시켜서 사람 재인식의 성능을 높인다.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.35 no.1
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• pp.15-21
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• 2024

Autism spectrum disorder (ASD) is diagnosed by the clinical decision of a trained professional based on the Diagnostic and Statistical Manual for Mental Disorders, Fifth Edition or International Classification of Diseases 11th Revision diagnostic criteria. To obtain information for diagnostic formulation, professionals should explore detailed developmental history, and can use structured or semi-structured assessment tools to observe interaction between the child and parents or strangers. Diagnostic assessment should include a profile of the strength and weaknesses of the individual and should be conducted using an optimal approach by a multidisciplinary team with appropriate techniques and experience. Assessment of language, cognitive, neuropsychological, and adaptive functioning should be conducted in ASD individuals prior to establishing an individualized treatment plan. Genetic testing, brain magnetic resonance imaging or electroencephalogram testing can be considered for identification of underlying causes.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.1
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• pp.23-31
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• 2009

Recently, biometric techniques such as face recognition, finger-print recognition and iris recognition have been widely applied for various applications including door access control, finance security and electric passport. This paper presents the method of using finger-vein pattern for the personal identification. In general, when the finger-vein image is acquired from the camera, various conditions such as the penetrating amount of the infrared light and the camera noise make the segmentation of the vein from the background difficult. This in turn affects the system performance of personal identification. To solve this problem, we propose the novel and fast method for extracting the finger-vein region. The proposed method has two advantages compared to the previous methods. One is that we adopt a locally adaptive thresholding method for the binarization of acquired finger-vein image. Another advantage is that the simple morphological opening and closing are used to remove the segmentation noise to finally obtain the finger-vein region from the skeletonization. Experimental results showed that our proposed method could quickly and exactly extract the finger-vein region without using various kinds of time-consuming filters for preprocessing.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2002.05a
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• pp.81-86
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• 2002

In current CBR(Case-Based Reasoning) systems, the case adaptation is usually performed by rule-based method that use rules hand-coded by the system developer. So, CBR system designer faces knowledge acquisition bottleneck similar to those found in traditional expert system design. In this thesis, 1 present a model for learning method of case adaptation knowledge using case base. The feature difference of each pair of cases are noted and become the antecedent part of an adaptation rule, the differences between the solutions in the compared cases become the consequent part of the rule. However, the number of rules that can possibly be discovered using a learning algorithm is enormous. The first method for finding cases to compare uses a syntactic measure of the distance between cases. The threshold fur identification of candidates for comparison is fixed th the maximum number of differences between the target and retrived case from all retrievals. The second method is to use similarity metric since the threshold method may not be an accurate measure. I suggest the elimination method of duplicate rules. In the elimination process, a confidence value is assigned to each rule based on its frequency. The learned adaptation rules is applied in riven target Problem. The basic. process involves search for all rules that handle at least one difference followed by a combination process in which complete solutions are built.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04a
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• pp.41-47
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, $50-80\%$ of the maximum potential yield is lost by these 'environmental or abiotic stresses', which is approximately ten times higher than the loss by biotic stresses. Thus, Improving stress-tolerance of crop plants is an important way to improve agricultural productivity. In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.992-1000
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• 2005

Campylobacter is one of the emerging foodborne pathogens, and its worldwide incidence rate is extremely high. This study was undertaken to isolate and identify Campylobacter strains from chicken carcasses in the local markets, and analyze their characteristics regarding oxygen tolerance. They were isolated after aerobic enrichment and identified by biochemical, physiological, and morphological characteristics, PCR, and 16S rDNA sequencing. Their oxygen tolerances were analyzed in terms of the cell surface hydrophobicity, cell fatty acid composition, and oxidoreductase. Five strains of C. jejuni were isolated and identified from 61 isolates from 50 chickens. Among them, C. jejuni IC21 grew well in Brucella broth and commercial milk under aerobic condition. However, in the aerobic exposure, the cell surface hydrophobicity of C. jejuni IC21 was almost the same as the other isolates, even though its morphology changed from the spiral-bacilli form into the coccoid form. Fatty acid analyses showed that all Campylobacter strains had a high composition of $C_{19:1}$, cyclopropane fatty acid, and that the amount of the other fatty acids were very similar between them. Interestingly, however, only oxidoreductase activities of C. jejuni IC21 increased highly under aerobic exposure even though its activities were almost the same as the other C. jejuni strains just after microaerobic culture. It had 11.8 times higher catalase activity, 4.4 times higher for SOD, and 2.0 times higher for NADH oxidase activities. Therefore, in the case of the aero-adaptive C. jejuni IC21, expression of oxidoreductase significantly increased under oxidative stressed condition, which might allow it to survive for a longer time and grow on food under aerobic exposure. Such new strain might be one of the explanations for the increase of campylobacteriosis.

• Smart Structures and Systems
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• v.17 no.5
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• pp.819-835
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• 2016

In this paper, the activities carried out within the EU funded Clean Sky Joint Technology Initiative (JTI GRA) Project and aimed at developing a morphing flap, are illustrated. The reference device is a regional aircraft single slotted flap, enhanced with deforming capabilities to obtain improved hyper-lift performance. The design started with the identification of the internal architecture, intended to allow camber variations. A concentrated-hinge architecture was selected, for its ability to fit different curvatures and for the possibility of easily realizing an "armadillo-like" configuration, then avoiding the use of a complicate deformable skin. The flap layout is made of segmented ribs, elastically hinged each other and span-wise connected by conventional spars. Relative rotations of the rib elements are forced by SMA structural actuators, i.e., cooperating in the external loads absorption. Super-elastic SMA are used to make up recovery elastic elements, necessary to regain the original shape after activation. These further elements in turn contribute to the overall flap rigidity. After assessing the hinge number and the size of the SMA active and passive elements, the advanced design phase was dealt with. It was aimed at solving manufacturing issues and producing the executive drawings. The realized demonstrator was finally tested in lab conditions to prove its functionality in terms of whether target shape actuation or attained shape preservation under loads. On the basis of the numerical results and the experimental outcomes, precious hints were obtained for further developments of the concept.

• The Journal of the Korea Contents Association
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• v.7 no.2
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• pp.40-50
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• 2007

In this paper, we propose an efficient method for detecting and tracking multiple moving objects based on morphological region merging from real-time video sequences. The proposed approach consists of adaptive threshold extraction, morphological region merging and detecting and tracking of objects. Firstly, input frame is separated into moving regions and static regions using the difference of images between two consecutive frames. Secondly, objects are segmented with a reference background image and adaptive threshold values, then, the segmentation result is refined by morphological region merge algorithm. Lastly, each object segmented in a previous step is assigned a consistent identification over time, based on its spatio-temporal information. The experimental results show that a proposed method is efficient and useful in terms of real-time multiple objects detecting and tracking.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04b
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• pp.41-47
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, 50-80% of the maximum potential yield is lost by these 'environmental or abiotic stresses', which is approximately ten times higher than the loss by biotic stresses. Thus, improving stress-tolerance of crop plants is an important way to improve agricultural productivity. In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.