CASE REPORT : Hypothalamic Extraventricular Neurocytoma (EVN) in a Pediatric Patient: A Case of EVN Treated with Subtotal Removal Followed by Adjuvant Radiotherapy

( Minjae Cho ),( Jin Deok Joo ),( Baek Hui Kim ),( Gheeyoung Choe ),( Chae Yong Kim ) 대한뇌종양학회 대한신경종양학회 2016 Brain Tumor Research and Treatment Vol.4 No.1

Extra ventricular neurocytoma (EVN) is a rare brain tumor with histologic features similar with a central neurocytoma, but located outside of the ventricular system. In this study, we present an unusual case of hypothalamic EVN in a 14-year-old patient. The patient underwent subtotal removal and had tumor relapse. The patient was then treated using intensity modulated radiation therapy, and the tumor remained stable for 24 months. This case report may be important in that this is the first pediatric case of EVN located in the hypothalamic region. EVN has similar radiologic features with pilocytic astrocytomas and therefore a hypothalamic EVN may be misdiagnosed as a hypothalamic glioma. Also, the pathologic-radiologic-clinical correlation of EVN located in the hypothalamic area may be different from that of EVNs originating from other usual sites.

The Role of Adjuvant Treatment in Patients with High-Grade Meningioma

Cho, Minjae,Joo, Jin-Deok,Kim, In Ah,Han, Jung Ho,Oh, Chang Wan,Kim, Chae-Yong The Korean Neurosurgical Society 2017 Journal of Korean neurosurgical society Vol.60 No.5

Objective : To investigate the efficacy of adjuvant treatment in patients with high-grade meningioma. Methods : A retrospective analysis was performed for patients with high-grade meningioma, World Health Organization grade 2 or 3, in a single center between 2003 and 2014. The patients were reviewed according to age at diagnosis, sex, the location of meningioma, degree of tumor resection, histological features, and type of adjuvant treatment. These factors were analyzed by Firth logistic regression analyses. Results : Fifty-three patients with high-grade meningioma were enrolled. Thirty-four patients received adjuvant treatment; conventional radiotherapy or radiosurgery. Clinical follow-up ranged from 13-113 months with a median follow-up of 35.5 months. Gross total removal (GTR), Simpson grade 1 or 2, was achieved in 29 patients and, among them, 13 patients received adjuvant treatment. In the other 24 patients with non-GTR, conventional adjuvant radiotherapy and radiosurgery were performed in 11 and 10 patients, respectively. The other 3 patients did not receive any adjuvant treatment. Radiation-related complications did not occur. Of the 53 patients, 19 patients had suffered from recurrence. The recurrence rate in the adjuvant treatment group was 23.5% (8 out of 34). On the other hand, the rate for the non-adjuvant treatment group was 57.9% (11 out of 19) (odds ratio [OR]=0.208, p=0.017). In the GTR group, the recurrence rate was 7.5% (1 out of 13) for patients with adjuvant treatment and 50% (8 out of 16) for patients without adjuvant treatment (OR=0.121, p=0.04). Conclusion : Adjuvant treatment appears to be safe and effective, and could lead to a lower recurrence rate in high-grade meningioma, regardless of the extent of removal. Our results might be used as a reference for making decisions when planning adjuvant treatments for patients with high-grade meningioma after surgery.

Design and Control of Pneumatic System for Recycling Classification of Non-Ferrous Metals

Minjae Cho,Eunsung Kwon,Kyi-Hwan Park 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.9 No.2

South Korea is a resource-dependent country that relies on the import of most metal resources. Therefore, we should save resources through recycling. In particular, the recycle rate of non-ferrous metals is very low. This is due to the limitations of the recycling technology currently in use. To overcome these limitations, non-ferrous metal recycling studies using laser induced breakdown spectroscopy are underway. In this paper, we will discuss an automatic metal classification system that receives metal information from a laser-induced breakdown spectrum and classifies a metal scrap by material. Currently, sorting systems use non-contact pneumatic systems. Compared to the contact method, the system is durable and is controlled at high-speed. This is because the system does not directly contact the metal scrap. Therefore, we will study how to effectively use the flow rate by modeling the pneumatic system.

Harvesting Cost and Productive of Tree-Length Thinning in a Pinus densiflora Stand Using the Tower Yarder (HAM300)

Minjae Cho,Koohyun Cho,Eungjin Jeong,Jun Lee,Byoungkoo Choi,Sangkyun Han,Dusong Cha 강원대학교 산림과학연구소 2016 Journal of Forest Science Vol.32 No.2

Logging equipment and method have a major influence on harvesting productivity and cost. This study investigated the productivity and operational costs of tree-length cable yarding system using HAM300, a domestically developed tower yarder. We tested HAM300 for thinning operation in Pinus densiflora stands at Gangreung, Gangwon-do on April, 2014. To assess the productivity we conducted time study for each stage of the operation. When the average time/cycle was examined for each stage of the operation, the longest was for yarding (241 sec), followed by delimbing (237 sec), felling (153 sec), and processing (103 sec). Furthermore, productivity for felling was 8.6 m3/hr, followed by delimbing (5.1 m3/hr), yarding (3.5 m3/hr), and processing (8.1 m3/hr). The total cost for the tree-length logging system was 58,446 won/m3, of which the majority was incurred by the yarding cost at 46,217 won/m3 (79.3%), whereas the lowest cost was for felling at 2,359 won/m3 (4.1%). We suggest that it is necessary to foster specialized operators and provide training in operating the tower yarder thereby implementing efficient harvesting system resulting from low-cost yarding.

Harvesting Cost and Productive of Tree-Length Thinning in a Pinus densiflora Stand Using the Tower Yarder (HAM300)

Cho, Minjae,Cho, Koohyun,Jeong, Eungjin,Lee, Jun,Choi, Byoungkoo,Han, Sangkyun,Cha, Dusong Institute of Forest Science 2016 Journal of Forest Science Vol.32 No.2

Logging equipment and method have a major influence on harvesting productivity and cost. This study investigated the productivity and operational costs of tree-length cable yarding system using HAM300, a domestically developed tower yarder. We tested HAM300 for thinning operation in Pinus densiflora stands at Gangreung, Gangwon-do on April, 2014. To assess the productivity we conducted time study for each stage of the operation. When the average time/cycle was examined for each stage of the operation, the longest was for yarding (241 sec), followed by delimbing (237 sec), felling (153 sec), and processing (103 sec). Furthermore, productivity for felling was $8.6m^3/hr$, followed by delimbing ($5.1m^3/hr$), yarding ($3.5m^3/hr$), and processing ($8.1m^3/hr$). The total cost for the tree-length logging system was $58,446won/m^3$, of which the majority was incurred by the yarding cost at $46,217won/m^3$ (79.3%), whereas the lowest cost was for felling at $2,359won/m^3$ (4.1%). We suggest that it is necessary to foster specialized operators and provide training in operating the tower yarder thereby implementing efficient harvesting system resulting from low-cost yarding.

웹 문서의 개념 지식과 그래프 구조를 이용한 정보 분류 및 추출 시스템

조민재(Minjae Cho),황수철(Hwang Sucheol),김기태(Kitae Kim) 한국정보과학회 1999 한국정보과학회 학술발표논문집 Vol.26 No.1B

최근 인터넷 정보의 폭발적 증가로 인해 원하는 정보만을 추출해 내는 요구가 많아지고 있다. 이를 해결하기 위해 본 논문에서는 개념 기반의 그래프 구조로 인식되는 웹 페이지에서 미리 정의하지 않은 정보를 추출하는 시스템을 제안한다. 제안한 시스템에서는 하이퍼링크와 웹 페이지를 제 1순위 논리 표현법으로 그래프 구조로 인식하여 해당 영역으로 분류하고, 이 그래프 구조와 분류과정에서 획득한 개념 지식을 이용하여 정보를 추출해 낸다. 본 시스템은 분류 부 시스템과 추출 부 시스템으로 이루어 있으며 각 부 시스템 별로 별도의 지식 베이스와 추론 엔진을 가지고 있어 해당 영역에 맞게 지식 베이스와 추론 엔진을 연결하면 어떠한 정보든지 추출해 낼 수 있다.

동형암호를 위한 재구성형 NTT 아키텍처의 FPGA 구현

조민재(Minjae Cho),이재혁(Jaehyeok Lee),이한호(Hanho Lee) 대한전자공학회 2022 대한전자공학회 학술대회 Vol.2022 No.6

실시간 비철금속 선별을 위한 공압 시스템 유량 제어

조민재(Minjae Cho),박기환(Kiyhan Park) 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.12

환원슬래그 혼합점토의 일축압축강도 특성

조민재(Cho, Minjae),윤여원(Yoon, Yeowon),김재윤(Kim, Jaeyoon) 한국지반환경공학회 2012 한국지반환경공학회논문집 Vol.13 No.6

철강 생산량이 증가함에 따라 부산물로 발생하는 슬래그의 재활용에 대한 관심이 커지고 연구가 활발히 진행되어 왔다. 현재 국내에서는 고로 슬래그에 대한 연구는 많이 이루어지고 있지만, 제강 슬래그에 대한 연구는 미비한 실정이다. 또한 제강슬래그 중에서도 전기로 산화슬래그에 대한 콘크리트 골재로의 활용에 관한 연구가 진행되고 있을 뿐 전기로 환원슬래그에 대한 연구실적은 거의 없는 실정이다. 최근 전기로 환원슬래그에 대한 토목용 성토 및 뒤채움 재료로서의 활용가능성 여부에 관한 연구가 진행된바 있고, 점토지반 개량재로서의 가능성을 확인한 바 있다. 따라서 본 연구의 목적은 전기로 제강 환원슬래그를 연약지반개량을 위한 토목재료로서 활용 가능성을 검토하고 최적의 혼합비를 찾는데 있다. 환원슬래그에 대한 SEM, XRF, XRD 시험 등을 통해 성분 분석을 하고 또한 환원슬래그 혼합점토에 대한 일축압축강도 시험을 통해 점토지반에 환원슬래그를 혼합하였을 때의 강도 증진 효과에 대한 검토를 하였다. 이 시험을 통해 환원슬래그 혼합에 따른 뚜렷한 강도증진 효과를 확인하였으며, 이를 바탕으로 연약지반처리에 있어 환원슬래그의 활용가능성을 판단할 수 있었다. 본 연구에 대한 기대효과는 산업 부산물의 활용에 따른 환경보전 및 재활용 측면과 전기로 환원슬래그의 연약지반개량용 토목재료로서의 활용에 있다고 하겠다. With the increase of steel production research interest on the recycling of slag as a by-product also increases steadily. Currently in Korea a lot of researches on blast-furnace slag have been made. However, the researches on the steel slag have been rarely made. Also, a research of steel slag, especially the use of oxidation furnace slag as aggregates for concrete progress, is performing actively, but the research results on the furnace slag are almost nothing. Recently, the research about the furnace slag as backfill material and embankment material confirmed the possibility of the clay soil amendment. Therefore, the object of this study is to review the possibility as civil engineering materials for soil improvement and to find the optimum mixture ratio of furnace slag. This research analyzed the ingredient component of the reduced slag by SEM, XRF, XRD tests and examined the strength increase using unconfined compression tests when the clay and reduced slag are mixed each other. Through this test, the definite strength increase is confirmed according to the mixture of the reduced slag and the possibility of soil improvement is also confirmed based on this result. The object of the study is both utilizing the by-product for civil engineering purpose and effective recycling by the application of the furnace slag for soil improvement.

Development of Flexible Eye Shield Phantom for Artifact-free CT images in Electron Beam Radiotherapy

Minjae Choi,Jindong Cho,GeumBong Yu,Seonghee Kang 대한방사선방어학회 2023 대한방사선방어학회 학술발표회 논문요약집 Vol.2023 No.4