임베디드 보드 기반의 교육용 차동 구동 로봇 플랫폼 개발

최현주,이동현,Choi, Hyeon-Ju,Lee, Dong-Hyun 대한임베디드공학회 2022 대한임베디드공학회논문지 Vol.17 No.2

This paper proposes a mobile robot platform for education that can experiment with various autonomous driving algorithms such as obstacle avoidance and path planning. The platform consists of a robot module and a remote controller module, both of which are based on the Arduino Nano 33 IoT embedded board. The robot module is designed as a differential drive type using two encoder motors, and the speed of the motor is controlled using PID control. In the case of the remote controller module, a command to control the robot platform is received with a 2-axis joystick input, and an elliptical grid mapping technique is used to convert the joystick input into a linear and angular velocity command of the robot. WiFi and Zigbee are used for communication between the robot module and the remote controller module. The proposed robot platform was tested by measuring and comparing the linear velocity and angular velocity of the actual robot according to the linear velocity and angular velocity commands of the robot generated by the input of the joystick.

하악에 발생된 결체조직성 섬유종

최현주,박영희,최갑식,Choi Hyun-Ju,Park Young-Hee,Choi Karp-Shik 대한영상치의학회 1999 Imaging Science in Dentistry Vol.29 No.1

Desmoplastic fibroma is a rare. benign intraosseous fibroblastic tumor. which is locally aggressive. It is osseous counterpart of soft tissue fibromatosis. The authors experienced the patient who complained persistent mouth opening limitation with mild swelling on the left mandibular angle area. After careful analysis of clinical. radiological and histopathological findings. we diagnosed as desmoplastic fibroma of the mandible. The results were as follows: 1. Main clinical symptoms were mouth opening limitation which had been persistent for 9 months and mild swelling on the left mandibular angle area. 2. Radiographs showed the radiolucent lesion and expansion of lingual cortex. CT finding is homogeneous soft tissue mass with expansion of left mandibular ramus. Destruction of medial wall of ramus and invasion to adjacent soft tissue is also seen. 3. Histopathologically, plump spindle shaped fibroblasts arranged in bundles or fascicles are observed. The cells of tumor are infiltrating into muscle fiber with destruction of bony trabeculae and merged with surrounding salivary gland.

지루 피부염 환자의 피지 조성에 관한 연구

최현주,임성빈,이승헌 ( Hyun Joo Choi,Sung Bin Lim,Seung Hun Lee ) 대한피부과학회 1991 대한피부과학회지 Vol.29 No.6

N/A We attempted to examine the compositions of seborrheic lipids from the scalp of the human adult males and the patints who have the seborrheic dermatitis by the ?hin layer chromatography(TLC) and the photodensitometer. The human skin surface lipids are composed of the seborrheic lipids from the sebaceous glands and epidermal lipids from the ediermis. The sebaceous lipids were known that they played the role to protect the skin and they had the pathophysiologic role in the seborrheic dermatitis and the ance. We observed that the sebacous lipids were composed of squalene, ??olestrol ester, wax ester, triglyceride, free fatty acid, and saturated hydrocabon in both the control group and the patient group. In the mean values of the ratio of the seborrheic lipids composition, the ratio of squalene and cholesterol eater were higher, and the ratio of free fatty acid and triglyceride were lower in the patient group than in the control group, and the ratio of wax ??ster which was originated from sebaceous glands was no difference between two groups. Thus, n?the seborrheic dermatitis, there was no change in the sebum secertion rate, but the lipid compositions were changed.

유방의 침윤성 미세유두암종의 세침흡인 세포검사

최현주,정지한,신정하,민기옥,강석진,이교영,유진영,Choi, Hyun-Joo,Jung, Ji-Han,Shin, Jung-Ha,Min, Ki-Ouk,Kang, Seok-Jin,Lee, Kyo-Young,Yoo, Jin-Young 대한세포병리학회 2007 대한세포병리학회지 Vol.18 No.1

Invasive micropapillary carcinoma (IMPC) of the breast is recently described rare variant of invasive ductal carcinoma. This variant has a distinctive histological features and aggressive biological behavior. We reviewed the cytologic features of eight cases of IMPC. The cytologic smears showed moderate to high cellularity and the tumor tissue was composed of atypical, angulated, cohesive clusters of neoplastic cells with a papillary to tubuloalveolar architecture, and a morular growth pattern without fibrovascular cores was seen on the histopathology. IMPC of the breast has distinctive cytologic features and it is important to make an early diagnosis via fine needle aspiration cytology due to this tumor's aggressive behavior.

집합 결합과 신경망을 이용한 복합질환의 예측

최현주,김승현,위규범,Choi, Hyun-Joo,Kim, Seung-Hyun,Wee, Kyu-Bum 한국정보처리학회 2008 정보처리학회논문지B Vol.15 No.4

복합질환은 다수의 유전자들이 상호작용하여 유발되는 질병으로서, 여러 유전자들이 관여한다는 복잡성 때문에 전통적인 분석 방법을 적용하는데 한계가 있다. 최근에는 기계학습 기법을 이용한 새로운 분석 방법들이 제안되고 있다. 신경망은 이처럼 복잡한 데이터에서 일정한 패턴을 찾아 이를 분류하는데 적합한 모델이다. 그러나 다량의 데이터가 입력으로 들어오는 경우에 학습에 오랜 시간이 걸리고 패턴을 찾기가 어려워지는 단점이 있다. 본 연구에서는 다량의 SNP 데이터로부터 질병에 연관된 소수의 중요 SNP을 찾기 위한 통계학적인 방법인 집합결합(set association)과 신경망을 결합한 모델을 제시한다. 이 모델을 천식 관련 SNP 데이터에 적용하여 천식 발병 여부를 예측한 결과, 신경망만 사용했을 때보다 실행 시간도 빠르고 예측 정확도도 높았다. 이 모델은 다른 복합질환의 예측에도 효과적으로 사용할 수 있을 것으로 기대한다. Since complex diseases are caused by interactions of multiple genes, traditional statistical methods are limited in its power to predict the onset of a complex disease. Recently new approaches using machine learning techniques are introduced. Neural nets are a suitable model to find patterns in complex data. When large amount of data are fed into a neural net, however, it takes a long time for learning and finding patterns. In this study we suggest a new model that combines the set association, which is a statistical technique to find important SNPs associated with complex diseases, and neural network. We experiment with SNP data related to asthma to test the effectiveness of our model. Our model shows higher prediction accuracy and shorter execution time than neural net only. We expect our model can be used effectively to predict the onset of other complex diseases.

자궁경부 Adenoma Malignum의 세포학적 소견 - 1예 보고 -

최현주,김영신,이교영,강창석,심상인,Choi, Hyun-Joo,Kim, Young-Shin,Lee, Kyo-Young,Kang, Chang-Suk,Shim, Sang-In 대한세포병리학회 1998 대한세포병리학회지 Vol.9 No.2

Adenoma malignum is an extremely well-differentiated variant of cervical adenocarcinoma in which the cells composing the tumor lack the typical cytological features of malignancy. The prognosis of this rare tumor is poor in spite of high degree of differentiation. The cytologic characteristics are extremely bland so frequently make a confusion of adenoma mailgnum with endocervical glandular hyperplasia. We report a case of adenoma malignum in a 35-year-old woman who complained of mucoid vaginal discharge and vaginal bleeding. The cervicovaginal smear showed endocervical cells exhibiting a spectrum of atypical chances. The cells were arranged in multilayered strips and monolayered sheets. Individual cells ranged from cuboidal to columnar; typically the columnar cells had abundant lacy or vacuolated cytoplasm. The smear showed the majority of only atypical cells and small numbers of frankly malignant cells.

타액선의 다형성 선종에서 발견한 암종의 세침흡인 세포학적 소견 -5 예 보고-

최현주,김활웅,함의근,박인애,Choi, Hyun-Joo,Kim, Hwal-Woong,Ham, Eui-Keun,Park, In-Ae 대한세포병리학회 2001 대한세포병리학회지 Vol.12 No.2

Carcinoma ex pleomorphic adenoma(CXPA) is a rare malignant tumor of the salivary gland, fine needle aspiration cytology(FNAC) of which are rarely reported. We retrospectively reviewed FNAC of five cases of histologically proven CXPA of the salivary glands diagnosed in Seoul National University Hospital to evaluate their cytologic characteristics. Histologically, the carcinoma components were low-grade in three cases and high-grade in two cases. The cytologic diagnosis were malignancy in two cases(40%), suspicious for malignancy in one(20%), and benign(pleomorphic adenoma) in two(40%). All of the high-grade carcinomas were correctly diagnosed by FNAC, however, 2 cases of low-grade carcinomas were diagnosed as benign by FNAC. The low sensitivity in cytologic diagnosis is due to interpretative difficulties in low-grade tumors. The characteristic cytologic features of CXPA were high cellularity, necrotic, bloody, and inflammatory background, marked nuclear overlapping, coarsely granular chromatin, prominent macronucleoli, and atypical mitosis in epithelial component in addition to the typical biphasic pattern of pleomorphic adenoma consisting of epithelial cells admired with spindle-shaped cells and chondromyxoid stroma. Even though low-grade tumors show mild pleomorphism, the cytologic findings of necrotic background, moderate to high cellularity, and nuclear overlapping could lead to an accurate cytodiagnosis of CXPA.

자궁경부 세포도말 검사에시 미세침윤성 편평세포암종의 세포학적 분석

최현주,박인애,Choi, Hyun-Joo,Park, In-Ae 대한세포병리학회 2001 대한세포병리학회지 Vol.12 No.1

Whlie cytologic characteristics of squamous dysplasia, carcinoma in situ, and invasive squamous cell carcinoma of the uterine cervix are well documented, relatively few studios have dealt with the cellular features of microinvasive carcinoma. In order to describe the cellular characteristics of microinvasive squamous cell carcinoma, we retrospectively reviewed 45 cervovaginal smears(15 carcinoma in situ, 15 microinvasive cancer, 15 invasive cancer) which were confirmed by histologic examination of specimens obtained by hysterectomy at the Seoul National University Hospital during S years from 1995 to 1999. The cytologic features about tumor diathesis, inflammatory background, ceil arrangement, anisonucleosis, nuclear membrane irregularity, nuclear chromatin pattern, and nucleoli were observed. The cytologlc characteristics of microinvasive squamous cell carcinoma of the uterine cervix are syncytial pattern, mild tumor diathesis, the irregularity of nuclear membrane, irregularly distributed nuclear chromatin, and occurrence of micronucleoli. But, correlation between the depth of Invasion and the cytologic feature had limited value.

열분해법으로 형성된 산화크롬 박막의 자기적 특성

최현주,임대순,이전국,Choi, Hyun-Ju,Lim, Dae-Soon,Lee, Jeon-Kook 한국세라믹학회 2004 한국세라믹학회지 Vol.41 No.9

(110) 배향 TiO$_2$ 단결정 위에 성장시킨 CrO$_2$(110) 박막의 결정 구조, 미세구조와 자기적 특성의 상관 관계에 대해 연구하였다. 소스 물질로는 CrO$_3$ 분말을 사용하였으며, 열분해 화학증착법으로 CrO$_2$박막을 형성하였다. (110) 배향된 TiO$_2$루타일 단결정 위에 형성된 CrO$_2$ 박막은 (110) 방향으로 우선 배향되었고, 미세구조적으로 평활한 박막을 형성하였다. 흘려주는 산소량이 많을수록 CrO$_2$ 박막의 두께가 두꺼워지고 저항치가 낮았으며, 음의 자기저항치의 변화 및 자기 이력 곡선에서 보자력과 잔류 자화 값이 감소하는 경향을 보였다. We report the magnetic properties, microstructures, and crystal orientations of the CrO$_2$ thin films on TiO$_2$ single crystals. CrO$_2$ thin films were deposited by thermal decompositions with CrO$_3$ source materials. The microstructure of (110) oriented CrO$_2$ thin films deposited on (110) TiO$_2$ single crystals were uniform. As the oxygen flow rates increased, the resistivity, coercive field, and remnant magnetization of the CrO$_2$ thin films on TiO$_2$ single crystals decreased.

Surface Modification of Poly(dimethylsiloxane) Microchip by Using Cetyltrimethylammonium Bromide (CTAB)

최현주,이경복,Kuk Ro Yoon,최인성,우성일,Kyungseong Choi,Sang Chun Lee 대한화학회 2004 Bulletin of the Korean Chemical Society Vol.25 No.4

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