슬러리 펌프용 고크롬 주철의 교반 가속 부식법

이준섭,이준형,이예진,오준석,김정구,이재현,Lee, Jun-Seob,Lee, Jun-Hyeong,Lee, Ye-Jin,Oh, Jun-Seok,Kim, Jung-Gu,Lee, Je-hyun 한국부식방식학회 2022 Corrosion Science and Technology Vol.21 No.5

Stir-accelerated corrosion test of a high chromium cast iron was attempted in 0.1 mol dm^-3 H₂SO₄ + 0.05 mol dm^-3 HCl + 10 wt% SiC solution for 48 h at room temperature or at 45 ℃. The high chromium cast iron was composed of 2.8 wt% C and 27 wt% Cr and balanced with Fe. The high chromium cast iron was positioned into a 500 mL beaker with stirring of the solution at 1050 rpm using a magnetic hot plate. The corrosion rate was increased by agitating the solution. In addition, the corroded depth of the high chromium cast iron surface was increased by agitating the solution. The surface morphology of the high chromium cast iron after the stir-accelerated corrosion test revealed that a dendritic austenite phase partially remained in the corroded region after agitating the solution, indicating that solution movement during agitating could accelerate the corrosion rate of the high chromium cast iron.

산성 용액에서 고크롬 주철의 전면 부식 거동

이준섭 ( Jun-seob Lee ),이준형 ( Jun-hyung Lee ),오준석 ( Jun-seok Oh ),이재현 ( Je-hyun Lee ) 한국부식방식학회 2021 Corrosion Science and Technology Vol.20 No.6

The effect of carbon addition on the general corrosion behavior of high-chromium cast iron (HCCI) was studied by a scanning electron microscope with energy dispersive spectroscopy (SEM-EDS) or electron back-scattered diffraction (EBSD), or electrochemical polarization techniques in 0.1 mol dm^-3 H₂SO₄ + 0.05 mol dm^-3 HCl at room temperature. The addition of 2.1-2.8 wt% carbon to HCCI increased the fraction of eutectic austenite and eutectic carbide phases, while that of HCCI decreased the fraction of the primary austenitic phase. Potentiostatic polarization of the HCCI at -0.35 V_SSCE or 0.0 V_SSCE resulted in preferential general corrosion of the primary austenitic or eutectic austenitic phases, respectively. The decrease in corrosion current density and the shift in noble corrosion potential direction with increasing carbon content in the HCCI indicated that the fraction and the chemical composition of austenitic (primary and eutectic) and carbide phases were strongly related to the general corrosion behavior of the HCCI.

가변 페이징 영역 설정을 이용한 IP 페이징에서의 부하 분산 기법

이준섭(Jun-Seob Lee),민재홍(Jae-Hong Min) 한국통신학회 2003 한국통신학회 학술대회 및 강연회 Vol.2003 No.4

3차원 CG설계를 이용한 실내건축공사의 원가 및 리스크 절감

이준섭 ( Lee Jun-seob ),방홍순 ( Bang Hong-soon ),김옥규 ( Kim Ok-kyue ) 한국건축시공학회 2021 한국건축시공학회 학술발표대회 논문집 Vol.21 No.1

These days, interior construction is performed to prevent the deterioration of old building finishings or to make distinctive designs. In case of interior construction, a construction cost is estimated through basic 2D drawings in the design step. Accordingly, an efficient construction plan and direction is established according to budget. In such a case, construction is dependent on 2D drawings. At that time, a risk can occur easily. This study is aimed at reducing the cost and risk of interior construction by implementing 3D drawings with the use of the visual data of 2D drawings. For accurate analysis, 2D drawings were completed, and then 3D interior construction modeling for various buildings was conducted with the 3D modeling software 3D Max. According to the 3D modeling, it reduced the cost and risk more than 2D drawings based design, and influenced the improvement in the understanding of orderers and workers.

내시경적 안와감압술을 시행한 갑상샘눈병증 환자에서 안와 구조와 안구돌출 변화의 관계

이준섭(Jun Seob Lee),강성모(Sung Mo Kang) 대한안과학회 2023 대한안과학회지 Vol.64 No.5

목적: 내시경적 안와감압술을 시행한 갑상샘눈병증 환자에서 수술 전후 안와 구조와 안구돌출 변화의 관계에 대해 알아보고자 하였다. 대상과 방법: 갑상샘눈병증을 진단받고 내시경을 이용하여 단독 안와내벽감압술을 시행받은 환자 18명의 33안을 대상으로 수술 전후안구돌출계 검사와 2차원 얼굴 전산화단층촬영을 이용하여 안와 구조와 연관된 지표들을 측정하였다. 단변량선형회귀분석을 시행하여 수술 후 안구돌출 변화와 관련성이 있는 것으로 확인된 변수들을 평가한 뒤, 다변량선형회귀분석을 시행하였다. 결과: 단변량선형회귀분석에서 수술 전 안와내벽의 길이(β=0.179, p=0.032)와 수술 후 결손된 안와내벽에서 안와첨부까지의 길이(β =-0.139, p=0.006)가 수술 후 안구돌출의 변화와 연관된 것으로 확인되었다. 두 가지 변수를 반영한 다변량선형회귀분석에서 수술후 안구돌출의 변화는 결손된 안와내벽에서 안와첨부까지의 길이(β=-0.118, p=0.019)와 관련이 있는 것으로 나타났다. 결론: 내시경적 안와감압술 후 안구돌출의 변화는 결손된 안와내벽에서 안와첨부까지의 길이와 관련이 있었다. 이를 토대로 감상샘눈병증 환자에서 안와감압술을 계획할 때 안구돌출 정도의 변화를 예측하는 지표로 고려해볼 수 있을 것이다. Purpose: To investigate orbital morphology parameters associated with exophthalmos changes in patients undergoing endoscopic orbital decompression to treat thyroid-related orbitopathy. Methods: In total, 33 eyes of 18 patients with thyroid-related orbitopathy who underwent endoscopic orbital decompression were included in this retrospective study. Data were collected before and 6 months after surgery. We performed Hertel exophthalmometry and derived orbital morphology parameters from two-dimensional facial computed tomography records. Parameters associated with exophthalmos reduction on univariate linear regression analysis were subjected to multivariate linear regression analyses. Results: Univariate linear regression showed that the preoperative length of the medial orbital wall (β = 0.179, p = 0.032) and the postoperative distance from the cone apex to the medial wall defect (β = -0.139, p = 0.006) were associated with exophthalmos reduction after endoscopic orbital decompression surgery. Multivariate linear regression of these two parameters showed that the distance from the apex to the medial wall defect was associated with exophthalmos reduction (β = -0.118, p = 0.019). Conclusions: The postoperative distance from the cone apex to the medial wall defect was associated with exophthalmos reduction. In patients with thyroid-related orbitopathy, this association should be considered when planning endoscopic orbital decompression.

염수 환경에서 Inconel 718의 국부 부식 거동

이준섭 ( Jun-seob Lee ),이예진 ( Yejin Lee ),권순일 ( Soon Il Kwon ),신정호 ( Jungho Shin ),이재현 ( Je-hyun Lee ) 한국부식방식학회 2021 Corrosion Science and Technology Vol.20 No.6

Localized corrosion behavior of Ni-based Inconel 718 alloy was investigated by electrochemical anodic polarization techniques in NACE TM 0177 A solution of 5 wt% NaCl + 0.5 wt% acetic acid at room temperature. After the solution heat treated at 1080 ℃ for 2.5 h, Inconel 718 was age-hardened at 780 ℃ for 8 h. The microstructure of the alloy surface was investigated by optical microscopic or scanning electron microscopic technique. The austenitic phase with the presence of metal carbides was observed on the surface of Inconel 718. Metal-carbides such as Nb-Mo and Ti-carbide with diameters of approximately 10 and 3 μm, respectively, were formed in Inconel 718. Anodic polarization results revealed that localized corrosion was observed at the interface between austenitic phase of a substrate and metal carbides. Difference in electrochemical property between a metal carbide and an austenitic substrate could provide an initiation site for localized corrosion of Inconel 718 surface.

학술회의 논문 : 기업지배구조에 있어 기관투자자의 역할 -일본어

이준섭 ( Lee Jun Seob ) 한일법학회 2002 한일법학 Vol.21 No.-

실시간 내장 멀티태스킹 커널의 개발에 재사용 가능한 객체지향 커널 프레임워크의 설계 및 구현

이준섭(Jun Seob Lee),전태웅(Taewoong Jeon),이승룡(Sungyoung Lee) 한국정보과학회 2000 정보과학회 컴퓨팅의 실제 논문지 Vol.6 No.2

실시간 내장 시스템은 운용 환경과 용도에 따라 멀티태스킹 커널이 지원해야 할 하드웨어 플랫폼과 자원 관리 정책이 다양하게 달라진다. 실시간 내장 시스템에 요구되는 크기와 성능 상의 제약 조건들을 엄격하게 만족해야 하는 멀티태스킹 커널을 새로운 시스템 서비스나 하드웨어에 맞게 개조하는 것은 쉽지 않다. 본 논문은 마이크로 프로세서 기반의 실시간 내장 멀티태스킹 커널의 구현에 재사용 가능한 객체지향 커널 프레임워크의 프로토타입을 객체 합성과 클래스 상속 메커니즘에 의거한 프레임워크 설계 패턴들을 적용하여 개발한 사례를 설명한다. 본 커널 프레임워크는 필요한 커널을 프레임워크의 개조와 확장을 통하여 효율적이고 일관성있게 생성할 수 있도록 하드웨어 환경과 시스템 자원 관리 정책에 의존적인 부분들이 프레임워크의 가변 부위(hot spot)로 분리된 추상 클래스들로 설계되어 있어서 높은 이식성과 개조성이 요구되는 마이크로 프로세서 기반 실시간 내장형 멀티태스킹 커널의 구현에 효과적으로 사용될 수 있다. Real-time embedded systems should accommodate many kinds of hardware platforms and resource management policies that vary depending on their operating environments and purposes. It is not an easy job to adapt a multitasking kernel to new system services and hardware platforms, as the kernel must strictly satisfy constraints on its size and performance. This paper describes the design and implementation of an object-oriented multitasking framework that can be reused for implementing microprocessor-based real-time embedded multitasking kernels. In this kernel framework, those parts that can vary depending on hardware platforms and system resource management policies are separated into the hot spots and encapsulated by abstract classes. Our framework thus can be effectively used to implement microprocessor-based real-time embedded kernels that demand high portability and adaptability.

UNS G41400 강의 인산염 표면 처리에 따른 국부 부식 저항성

이준섭 ( Jun-seob Lee ),박시욱 ( Siwook Park ) 한국부식방식학회 2023 Corrosion Science and Technology Vol.22 No.6

This study investigated the localized corrosion behavior of a UNS G41400 steel surface treated with manganese phosphate. The phosphate coating, primarily composed of oxygen (O), phosphorus (P), and manganese (Mn) elements, had an approximate thickness of 6 μm. The particles comprising the coating varied in size by several micrometers; smaller particles were mainly composed of O, P, Mn, and iron (Fe) elements, indicating incomplete formation of the manganese phosphate film. Potentiodynamic polarization curves revealed a decrease in anodic current after surface treatment and a shift in corrosion potential toward the noble direction after treatment. After immersion in a 3.5 wt% NaCl solution for 96 hours, localized corrosion was observed, with some regions retaining residual phosphate film. Even though localized corrosion occurred on the treated surface, it was less severe than that on the untreated UNS G41400 steel surface. These findings suggest that manganese phosphate coating improved resistance to localized corrosion.

IPv6 주소를 이용한 모바일 RFID 서비스 메커니즘의 설계

이준섭(Jun-Seob Lee),유상근(Sang-Keun Yoo),김용운(Yong-Won Kim),김형준(Hyoung-Jun Kim) 한국통신학회 2005 한국통신학회 학술대회 및 강연회 Vol.2005 No.12