지지부가 움직이는 모바일하버용 크레인의 동적 응답 최적설계

김현범(Hyun Bum Kim),이재준(Jae Jun Lee),장환학(Hwan Hak Jang),박경진(Gyung Jin Park) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.6

SAW-ED 시스템을 이용한 유/무기 소재 증착에 관한 연구

김현범(Hyun Bum Kim),김경환(Kyung Hwan Kim),시디쿠이 가야수딘(Siddiqi Ghayas),임종환(Jong Hwan Lim),양형찬(Hyoung Chan Yang),최경현(Kyung Hyun Choi) 한국기계가공학회 2016 한국기계가공학회지 Vol.15 No.5

In various industries, many researches studies have been done in using nano thin film fabrication technology. In the field of printed electronics, various electronic devices can be fabricated using a direct printing process of on multiple functional materials. It has the advantages of low prices, environment-friendly environmentally friendly, flexibleility, large scale, mass production produced, simple process and so on. In this study, a viable thin film fabrication technology has beenwas introduced using the surface acoustic wave mechanism for thin film deposition. Fabrication of thin films using organic, inorganic and composite of organic/inorganic materials have been were analyzed through the experimental research. In this experiment, organic material MEH:PPV, inorganic material ZnO and composite material MEH:PPV/ZnO have been depo sited as thin films.

하인두암 환자들의 발생 현황 및 치료 방법에 따른 결과 분석 : 국민건강보험공단 자료를 이용한 연구

김현범(Hyun-Bum Kim),한경도(Kyung-Do Han),주영훈(Young-Hoon Joo) 대한두경부종양학회 2021 대한두경부 종양학회지 Vol.37 No.2

Background/Objectives: The aim of this national population-based retrospective study was to analyze the status and treatment outcome in patients with hypopharyngeal cancer. Materials & Methods: Participants were included in the KNHIS national sample cohort who received a KNHIS health check-up in 2008 and 2009, and we followed these individuals until 2017. Patients were defined as having hypopharynx cancer if they had admissions records for hypopharynx cancer in their national health insurance data from 2010 to 2017. Results: The study cohort included 3,922 patients. According to our nationwide data, 3,533(90.1%) were male with a median age of 65.03±11.04 years at the time of diagnosis. Among parametric models for hypopharyngeal cancer prognosis, old age (Hazard ratio [HR]:1.92; 95% confidence interval[CI]:1.76-2.09), female (HR:0.77; 95% CI:0.66-0.89), and low socioeconomic status (HR:1.216; 95% CI:1.114-1.327) were significantly associated with survival. Compared with concurrent chemoradiotherapy, patients who received no treatment (HR, 1.88; 95% CI, 1.31-2.70), neoadjuvant chemotherapy followed by surgery (HR, 1.21; 95% CI, 1.04-1.41), and chemotherapy alone (HR, 1.16; 95% CI, 1.03-1.27) showed poor prognosis in hypopharyngeal cancer. Conclusion: Our data indicated that age, sex, and income were significant predictors of lifetime survival in patients with hypopharyngeal cancer. Treatment modalities were also associated with prognosis. The data have implications for treatment investigations and prevention strategies.

Sebekia benihana에서 Streptomyces coelicolor SCO4967 유전자 도입을 통한 하이드록실 사이클로스포린 A의 생전환

김현범 ( Hyun Bum Kim ),이미진 ( Mi Jin Lee ),한규범 ( Kyu Boem Han ),김응수 ( Eung Soo Kim ) 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 2010 한국미생물·생명공학회지 Vol.38 No.4

Actinomycetes are Gram-positive soil bacteria and one of the most important industrial microorganisms due to superior biosynthetic capabilities of many valuable secondary metabolites as well as production of various valuable bioconversion enzymes. Among them are cytochrome P450 hydroxylase (CYP), which are hemoproteins encoded by a super family of genes, are universally distributed in most of the organisms from all biological kingdoms. Actinomycetes are a rich source of soluble CYP enzymes, which play critical roles in the bioactivation and detoxification of a wide variety of metabolite biosynthesis and xenobiotic transformation. Cyclosporin A (CyA), one of the most commonly-prescribed immunosuppressive drugs, was previously reported to be hydroxylated at the position of 4th N-methyl leucine by a rare actinomycetes called Sebekia benihana, leading to display different biological activity spectrum such as loss of immunosuppressive activities yet retaining hair growth-stimulating side effect. In order to improve this regio-selective CyA hydroxylation in S. benihana, previously-identified several secondary metabolite up-regulatory genes from Streptomyces coelicolor and S. avermitilis were heterologously overexpressed in S. benihana using an ermE * promoter-containing Streptomyces integrative expression vector. Among tested, SCO4967 encoding a conserved hypothetical protein significantly stimulated region-specific CyA hydroxylation in S. benihana, implying that some common regulatory systems functioning in both biosynthesis and bioconversion of secondary metabolite might be present in different actinomycetes species.

지지부가 움직이는 모바일하버용 크레인의 동적 응답 최적설계

김현범(Hyun Bum Kim),이재준(Jae Jun Lee),장환학(Hwan Hak Jang),박경진(Gyung Jin Park) 대한기계학회 2012 大韓機械學會論文集A Vol.36 No.5

모바일하버는 해상에서 컨테이너 상하역 작업을 하는 새로운 해상물류 시스템이다. 모바일하버용 크레인과 같이 해상에서 작업하는 대형 구조물은 파도에 의해 발생하는 지지부의 운동으로 관성력의 영향을 크게 받는다. 따라서 구조물의 안전성에 대한 정확한 검증이 요구되며, 생산 비용을 줄이기 위해 경량화가 매우 중요하다. 이런 요구조건을 위해 동적 응답 최적설계를 수행한다. 등가정하중법은 동하중을 등가정하중으로 변환한 후, 정적 응답 최적화기법을 사용하여 문제를 해결하는 동적 응답 최적설계 방법이다. 지지부의 움직임을 고려한 등가정하중법을 제안하고, 제안한 방법으로 모바일하버용 크레인을 최적화한다. The mobile harbor is a new innovative system that delivers containers from a containership to a harbor without good infrastructure. A crane is installed on the deck of the mobile harbor and transfers the containers. The structure of the crane is influenced by the inertia force that occurs from a moving support. Thus an accurate safety verification considering the moving support is required. Lightweight of the crane structure is also significant in the design for low production cost and efficient operation. Dynamic response optimization can be exploited to achieve these two requirements. Equivalent static loads method is employed for dynamic response optimization of the crane. The equivalent static loads method transforms dynamic loads to equivalent static loads, and static response structural optimization with the transformed equivalent static loads are solved. The process proceeds in a cyclic manner. A new method is proposed to consider the moving supports and the structure of the mobile harbor is optimized using the proposed method.

표면파 기반의 풍력발전기 블레이드 표면상태 실시간 모니터링에 관한 연구

김경환(Kyung-Hwan Kim),양영진(Young-Jin Yang),김현범(Hyun-Bum Kim),양형찬(Hyung-Chan Yang),임종환(Jong-Hwan Lim),최경현(Kyung-Hyun Choi) 한국청정기술학회 2017 청정기술 Vol.23 No.1

현재 풍력발전은 우리나라에서 가장 주목 받고 있는 신재생에너지 분야로 많은 연구가 진행 중이다. 풍력발전을 구성하는 요소 중 핵심 요소인 블레이드에 손상이 발생할 경우에 발전 효율에 직접적인 영향을 미치므로 효율적인 유지보수를 위해 초기에 결함을 측정하는 기술이 매우 중요한 상태이다. 그러나 기존의 초음파 비파괴 검사 및 열화상 비파괴 검사는 소요시간이 길고 실시간 모니터링이 어려우므로 초기 결함 측정이 불가능하다. 기존의 문제를 보완하고자 본 논문에서는 표면파를 이용한 블레이드 표면상태 실시간 모니터링에 관한 연구를 수행하였다. 압전센서 기반의 시스템을 구성하여 블레이드 표면샘플에 대해 공정 변수 별 기초 성능 실험을 하였고, 소형 블레이드에 대해 공정변수 별 실험을 통해 블레이드의 크랙, 벗겨짐, 장애물 등을 실시간으로 모니터링이 가능한지 연구 하였다. These days much efforts are being dedicated to wind power as a potential source of renewable energy. To maintain effective and uniform generation of energy, defect preservation of turbine blade is essential because it directly takes effects on the efficiency of power generation. For the effective maintenance, early measurements of blade defects are very important. However, current technologies such as ultrasonic waves and thermal imaging inspection methods are not suitable because of long inspection time and non-real time inspection. To supplement the problems, the study introduced a method for real time defect monitoring of a blade surface based on surface wave technology. We examined the effect of various parameters such as micro-cracks and peelings on the propagation of surface wave.

연속공정기반 저온 상압 원자층 증착 시스템을 이용한 유무기 멀티레이어 배리어 박막에 관한 연구

이재욱(Jae-Wook Lee),김현범(Hyun-Bum Kim),최경현(Kyung-Hyun Choi) 한국기계가공학회 2018 한국기계가공학회지 Vol.17 No.3

In this paper, the organic material Poly(methyl methacrylate) PMMA is used with inorganic Al₂O₃ to fabricate organic-inorganic multilayer barrier thin films. The organic thin films are developed using a roll-to-roll electrohydrodynamic atomization system, whereas the inorganic are grown using a roll-to-roll low-temperature atmospheric pressure atomic layer deposition system. For the first time, these two technologies are used together to develop organic-inorganic multilayer barrier thin films in atmospheric condition. The films are grown under optimized parameters and classified into three classes based on the layer structures, when the total thickness of the barrier is maintained at ~ 160 nm. All classes of barriers show good morphological, optical and chemical properties. The Al₂O₃ films with a low average arithmetic roughness of 1.58 nm conceal the non-uniformity and irregularities in PMMA thin films with a roughness of 5.20 nm. All classes of barriers show a notably good optical transmission of ~ 85 %. The hybrid organic-inorganic barriers show water vapor and oxygen permeation in the range of ~ 3.2 × 10<SUP>-2</SUP>g/㎡/day and 0.015cc/㎡/day at 23℃ and 100% relative humidity. It has been confirmed that it can be mass-produced and used as a low-cost barrier thin film in various printing electronic devices.

미세전극 패터닝 기술을 이용한 바이오센서 패턴 구현

고정범(Jeong Beom Ko),김형찬(Hyung Chan Kim),양영진(Young Jin Yang),김현범(Hyun Bum Kim),양성욱(Seong Wook Yang),오승호(Seung Ho Oh),도양회(Yang Hoi Doh),최경현(Kyung Hyun Choi) 한국기계가공학회 2016 한국기계가공학회지 Vol.15 No.6

The Biosensor biosensor pattern was developed by via an EHD (electro-hydro-dynamics (EHD) patterning process that was performed under atmospheric pressure at room temperature in a single step. The drop diameter was smaller than nozzle diameter and applied high viscosity conductive ink was applied in the EHD patterning method to provide a clear advantage over the piezo and thermal inkjet printing techniques. The Biosensor’s biosensor’s micro electrode pattern was printed by via a continuous EHD patterning method using 3three- type types of control parameters parameter (input voltage, patterning speed, nozzle pressure). High viscosity (1000 cps) conductive ink with 75 wt% of silver nanoparticles was used for experimentation. The incremental result of impedance of biosensor impedance was measured between the antibody (10 ugμg/ml) to spore (0.1 ng/ml, 10 ng/ml, and 1 ugμg./ml) reaction at frequency 493 MHz frequency.

전기수력학 프린팅 기술을 이용한 미세전극 패턴의 리페어 공정 적용에 관한 연구

양영진(Young-Jin Yang),김수완(Soo-Wan Kim),김현범(Hyun-Bum Kim),양형찬(Hyung-Chan Yang),임종환(Jong-Hwan Lim),최경현(Kyung-Hyun Choi) 한국청정기술학회 2016 청정기술 Vol.22 No.4

최근 디스플레이 대형화 및 유연화로 인한 기존 ITO (indium tin oxide) 기반 TSP (touch screen panel)의 구현에 한계로 인한 대체 소재에 대한 다양한 연구가 진행 중이다. 기존 기술의 대체 소재로 메탈메쉬(Metal mesh) 방식에 대한 연구가 진행되고 상용화 수준까지 진행되었다. 그러나 시인성 및 모아레(Moire) 현상으로 인하여 5 μm 이하의 미세 전극 패턴이 필요하나 공정 중 패턴이 탈락하는 등의 문제로 낮은 수율의 문제가 있다. 기존의 레이저 CVD 리페어 공정에서 10 μm 이하의 패턴 형성의 한계, 위성액적 등의 문제로 인해 안정적인 미세전극 패턴 형성에는 어려움이 있었다. 본 연구에서는 5 μm 이하의 안정적인 패턴 형성을 위해서 다양한 점도에서 미세액적 토출이 가능한 전기수력학 프린팅 기술을 적용하였다. 5 μm 이하의 안정적인 미세 전극 패턴 형성을 위해 주요 변수의 변화에 따른 최적 공정 조건을 도출하였고 최적 공정 조건을 입력하여 리페어 공정 적용 가능성을 확인하였다. Recently, various research studies have been conducted and many are in progress for the suitable alternative materials for ITO based touch screen panel (TSP) due to limitations in size and flexibility. Various researches from all over the world have been attempted to fabricate the fine electrode less than 5μm for the rapid developing of display technology. Research is also being carried out in metal mesh methods using the existing technologies and alternative materials at commercial level. However, by using the existing technologies certain discrepancies are observed like low transparency and low yield which also results in the distortion of patterns. For repairing the damaged pattern, the conventional laser CVD technique has also been used but there are some challenges observed in CVD technique like achieving a stable fine electrode of 10 μm or less and avoiding the formation of satellite drops. To overcome these issues, a new printing process named Electrohydrodynamic (EHD) printing, has been introduced by which 5 μm fine patterns can be printed in one step. This EHDA printing technique has been applied to print very fine electrodes of 5 μm or less by using conductive inks of various viscosities. This study also presents the optimized process parameters for printing 5μm fine electrode patterns during experiments by controlling the applied voltage and supply flow rate. The 5μm repair electrodes were fabricated for repairing 50 μm shorted electrode samples.

유전체 스크리닝으로 선별된 Nocardiopsis 균주의 대장균 접합을 통한 유전자 도입전략 최적화

전호근 ( Ho Geun Jeon ),이미진 ( Mi Jin Lee ),김현범 ( Hyun Bum Kim ),한규범 ( Kyu Boem Han ),김응수 ( Eung Soo Kim ) 한국미생물생명공학회(구 한국산업미생물학회) 2011 한국미생물·생명공학회지 Vol.39 No.2

방선균은 그램양성 토양 박테리아로서 항생제, 항암제, 항구충제, 면역억제제 등 유용한 2차 대사산물을 생산하는 유용 산업미생물이다. 비록 대부분의 방선균이 속해있는 스트렙토마이세스는 지난 수 십 년간 분자수준에서의 연구가 집중적으로 진행되어 왔으나, 최근에 분리된 잠재적 유용성을 갖는 스트렙토마이세스 이외의 희소방선균들은 유전자 조작 시스템의 부재로 그 특성이 잘 규명되지 않고 있다. 본 연구에서는 독립적으로 분리된 180 여 방선균주들 중에서 희소 방선균만을 선별하기 위하여 중합효소연쇄반응을 이용한 유전체 스크리닝 전략을 시도하였으며, 이 전략을 통하여 7종의 희소방선균을 성공적으로 분리하였다. 특히 여러 생리활성 테스트를 통하여, 항진균 및 항생제 활성을 띄는 잠재적 유용성이 높은 노카이디옵시스 균주 MMBL010을 선별하였다. 또한 전통적인 방선균 유전자 조작기법이 작동하지 않는 본 MMBL010 균주를 대장균 접합을 통한 유전자 전달 시스템도 최적화시킴으로써, 유전체 스크리닝을 통한 유용희소방선균의 선별 및 유전자 조작시스템 구축은 궁극적으로 희소방선균의 잠재적 유용성을 극대화시킬 수 있는 효율적인 전략으로 사료된다. Actinomycetes, Gram positive soil bacteria, are valuable microorganisms which produce useful secondary metabolites including antibiotics, antiparasitic substances, anti-cancer drugs, and immunosuppressants. Although a major family of actinomycetes, known as streptomycetes, has been intensively investigated at the molecular level for several decades, a potentially valuable and only recently isolated non-streptomycetes rare actinomycetes (NSRA) family has been poorly characterized due to lack of proper genetic manipulation systems. Here we report that a PCR-based genome screening strategy was performed with approximately 180 independently isolated actinomycetes strains to isolate potentially valuable NSRA strains. Thanks to this simple PCR-based genome screening strategy we were able to identify only seven NSRA strains, followed by 16S rRNA sequencing for confirmation. Through further bioassays, one potentially valuable NSRA strain (tentatively named Nocardiopsis species MMBL010) was identified which possessed both antifungal and antibacterial activities, along with the presence of polyketide synthase and non-ribosomal peptide synthase genes. Moreover, Nocardiopsis species MMBL010, which was intrinsically recalcitrant to genetic manipulation, was successfully transformed via E. coli-driven conjugation. These results suggest that PCR-based genome screening, followed by the establishment of an E. coli-driven conjugation system, is an efficient strategy to maximize potentially valuable compounds and their biosynthetic genes from NSRA strains isolated from various environments.