Development of Exosome-embedded Microbubbles for Longer Diagnosis and Photodynamic-Immune Combination Therapy

Yongho JANG,Hyuncheol KIM 한국생물공학회 2022 한국생물공학회 학술대회 Vol.2022 No.4

Development of Adjuvant-fused Exosome-embedded Microbubbles for Sonodynamic-immunotherapy

Yongho JANG,Mingyu JEE,Hyuncheol KIM 한국생물공학회 2023 한국생물공학회 학술대회 Vol.2023 No.4

Topology Synthesis for Low Power Cascaded Crossbar Switches

Yongho Jang,Jungsoo Kim,Chong-Min Kyung IEEE 2010 IEEE transactions on computer-aided design of inte Vol.29 No.12

<P>Crossbar switch network has an increasing impact on such critical measures as throughput, latency, area, and power consumption of complex system-on-chip as technology scales to deep submicrometer. With high clock frequency crossbar switch network design, global wire delay and pipeline registers inserted for throughput are important because they affect area, frequency, and power consumption of the chip. The traffic congestion is also a very important factor because it leads to the lowering of throughput of the crossbar switch network. In this paper, we present a topology synthesis method for the low-power cascaded crossbar switch network satisfying the given bandwidth, latency, frequency, and area constraints. Unlike previous papers, our paper considers wire delay, traffic congestion, and pipeline register insertion at the same time. Experimental results show that the topologies optimized for power consumption for a given clock frequency consume less power than existing methods by up to 38.04%.</P>

Development of Exosome-embedded Microbubbles for Stable Ultrasound Imaging and Drug Delivery

Yongho JANG,Juhong YOUN,Hyuncheol KIM 한국생물공학회 2022 한국생물공학회 학술대회 Vol.2022 No.9

물리 시뮬레이션에 기반한 사실적인 키보드 타이핑 모션 생성

장용호(Yongho Jang),엄해광(Haegwang Eom),노준용(Junyong Noh) 한국컴퓨터그래픽스학회 2015 컴퓨터그래픽스학회논문지 Vol.21 No.5

사람의 손가락은 도구를 다루는 세밀한 동작을 하기 위해필수적인 부위이며, 캐릭터 애니메이션에 있어 자연스러운 손가락 움직임 표현은 중요한 이슈 중 하나이다. 그 중에서도 키보드 타이핑 모션은 다양한 관절을자연스럽게 사용하는 고난도동작이며, 기존 애니메이션 파이프라인을 활용해서는 만들기 쉽지 않다. 본 논문에서는 물리 시뮬레이션을이용하여 사실적인 키보드 타이핑 모션을자동으로 생성하는 방법을 제시한다. 물리 기반 시뮬레이션에서 타이핑 모션을잘수행하기 위해서는 손과 키보드 모델이 허용된 범위를 벗어나지 않아야 하며, 사용자의 입력에 맞는 키만 정확히 타건해야 한다. 또한 실제 키보드 타건을 관찰한 결과 항상 손의위치 및 자세는 키보드 위의 특정 기본 자세를 유지하려고 하며, 타건하는 손가락 이외의 움직임을 최소화하려는 경향을 확인할 수 있었고 이를 반영하고자 하였다. 이러한 다양한 제약 조건을 하나의 해결기에서 다루어실시간으로자연스러운키보드타이핑시뮬레이션결과를얻을수있고,이러한결과는애니메이션및가상현실기반 인터랙션 컨텐츠 등에서 유용하게 사용될 수 있다. Human fingers are essential parts of the body that perform complex and detailed motion. Expression of natural finger motion is one of the most important issues in character animation research. Especially, keyboard typing animation is hard to create through the existing animation pipeline because the keyboard typing typically requires a high level of dexterous motion that involves the movement of various joints in a natural way. In this paper, we suggest a method for the generation of realistic keyboard typing motion based on physics simulation. To generate typing motion properly using physics-based simulation, the hand and the keyboard models should be positioned in an allowed range of simulation space, and the typing has to occur at a precise key location according to the input signal. Based on the observation, we incorporate natural tendency that accompanies actual keyboard typing. For example, we found out that the positions of the hands and fingers always assume the default pose, and the idle fingers tend to minimize their motion. We handle these various constraints in one solver to achieve the results of real-time natural keyboard typing simulation. These results can be employed in various animation and virtual reality applications.

자동 변속기 시스템에서 비틀림 진동 저감을 위한 토크 컨버터 원심 진자 댐퍼 성능 해석에 관한 연구

장용호(Yongho Jang),이성구(Sungkoo Lee),이동수(DongSoo Lee) 한국자동차공학회 2022 한국 자동차공학회논문집 Vol.30 No.4

Torsional vibration is caused by engine torque fluctuation transmitted to the drive system in the powertrain system of an automatic vehicle. In particular, the torque fluctuation is directly transmitted to the automatic transmission due to the lock-up damper of the torque converter applied to improve fuel efficiency and increase efficiency. This may cause NVH problems and affect the structural life of the vehicle. As the driver’s desire for quietness and riding comfort increases, the vehicle’s weight reduction, torque increase, downsizing, and complex gearbox structure become significantly disadvantageous to the drivetrain and body vibration. Therefore, the existing single-stage lock-up damper of the torque converter surpasses its limit for the turbo charge engine. To overcome this, a system in which a centrifugal pendulum is mounted on a series two-stage spring is being developed. In this study, the analysis model was verified based on the actual vehicle measurement results in order to solve the problem that occurred during vehicle driving in a system wherein a centrifugal pendulum is mounted on a series two-stage spring. We proposed design variables by performing an analytical approach to the problem.

CFD를 활용한 크래프트 회수보일러 내부 노즈 아치 구조에 따른 열교환 효율 분석

장용호 ( Yongho Jang ),박현도 ( Hyundo Park ),임경필 ( Kyung Pil Lim ),박한신 ( Hansin Park ),김정환 ( Junghwan Kim ),조형태 ( Hyungtae Cho ) 한국공업화학회 2021 공업화학 Vol.32 No.2

크래프트 회수보일러(kraft recovery boiler)는 펄프 공정에서 생성된 흑액을 연소하여 발전용 스팀을 생산하는 장치이다. 특히 연소로 상단부에 존재하는 과열기(superheater)는 포화 증기가 연소가스와 열교환을 통해 과열 증기로 전환되는 구간으로, 연소가스와 포화 증기 사이의 열교환 효율 향상은 발전용 과열 증기 생산량 증가 및 발전 효율이 증가하므로 매우 중요하다. 과열기 하단부에 위치한 노즈 아치는 과열기의 부식의 원인이 되는 연소로에서 발생한 복사열을 막는 중요한 역할을 하지만, 연소가스 유동을 방해하여 포화증기와 열교환이 끝난 저온의 연소가스가 과열기를 나가지 못하고 재순환되어 열교환 효율을 저하시키는 직접적인 원인이 된다. 따라서 본 연구에서는 CFD를 활용하여 노즈아치 구조에 따른 재순환 영역의 크기와 연소가스 출구 온도를 비교하였다. 결과적으로 노즈 아치 하단부 각도를 106.5°에서 150°로 변경할 경우 연소가스의 재순환 영역이 감소하여 연소가스와 과열기 사이의 열교환 효율이 10.3% 향상되는 것을 확인하였다. A kraft recovery boiler produces steam for power generation by the combustion of black liquor from the kraft pulping process. Since saturated steam became superheated in a superheater above the furnace, it is important to increase the heat exchange efficiency for the superheated steam production and power generation. A nose arch at the bottom of the superheater is important for blocking radiation from the furnace which causes corrosion of the superheater. But the nose arch is the main reason for creating a recirculation region and then decreasing the heat exchange efficiency by holding cold flue gas after the heat transfer to saturated steam. In this study, the size of recirculation region and the temperature of flue gas at the outlet were analyzed by the nose arch structure using computational fluid dynamics (CFD). As a result, when the nose arch angle changed from 106.5° (case 1) to 150° (case4), the recirculation region of flue gas decreased and the heat exchange efficiency between the flue gas and the steam increased by 10.3%.

차량 구동계 시스템에서 원심 진자 DMF 성능 해석에 관한 연구

장용호(Yongho Jang),수레스(Suresh Kumar Jayachandran),이성구(Sungkoo Lee) 한국자동차공학회 2019 한국 자동차공학회논문집 Vol.27 No.9

In a vehicle drive system, torsional vibration is caused by engine fluctuation torque transmitted to the rotor system. This torsional vibration causes NVH problems and affects the life of the vehicle. DMF system based on torsional stiffness and inertia provided an effective capacity of releasing irregular vibration rising from the engine and transmitting to the transmission. However, engine irregularities have become more serious as a result of downsizing and uptorquing. The DMF system based on stiffness and inertia has reached its limits. Therefore, it is deemed necessary to propose new systems. Centrifugal pendulum and its application in the automotive area is considered as a major breakthrough. They are capable of counteracting the applied torque fluctuations of a given frequency over a range of operating amplitude, which turns out to be an efficient tool for filtration. In this study, we have shown the behaviors of the DMF pendulum in front wheel driveline with a seven-speed dual wet-clutch transmission. We designed a driveline rotor model and analyzed the frequency vibration. The contribution analysis was performed on each design factor of DMF, pendulum, and driveline system. We also performed a vehicle test in order to validate the optimized DMF pendulum performance in the actual driving conditions of a vehicle.

차량 구동계 시스템에서 원심 진자 DMF 성능 해석에 관한 연구

장용호(Yongho Jang),수레스(Suresh Kumar Jayachandran),이성구(Sungkoo Lee) 한국자동차공학회 2019 한국 자동차공학회논문집 Vol.27 No.10

In a vehicle drive system, torsional vibration is caused by engine fluctuation torque transmitted to the rotor system. This torsional vibration causes NVH problems and affects the life of the vehicle. DMF system based on torsional stiffness and inertia provided an effective capacity of releasing irregular vibration rising from the engine and transmitting to the transmission. However, engine irregularities have become more serious as a result of downsizing and uptorquing. The DMF system based on stiffness and inertia has reached its limits. Therefore, it is deemed necessary to propose new systems. Centrifugal pendulum and its application in the automotive area is considered as a major breakthrough. They are capable of counteracting the applied torque fluctuations of a given frequency over a range of operating amplitude, which turns out to be an efficient tool for filtration. In this study, we have shown the behaviors of the DMF pendulum in front wheel driveline with a seven-speed dual wet-clutch transmission. We designed a driveline rotor model and analyzed the frequency vibration. The contribution analysis was performed on each design factor of DMF, pendulum, and driveline system. We also performed a vehicle test in order to validate the optimized DMF pendulum performance in the actual driving conditions of a vehicle.

Development of Golf Shaft with Carbon Nanotubes and Marketing Strategy

Youngsam Lim,Jeonghoon Jang,Yongho Choi 보안공학연구지원센터 2014 International Journal of Software Engineering and Vol.8 No.12

It was reported that golf equipment market is expected to increase continuously and quickly. However, Korean golf organizations could not produce high-end technology products through scientific research and development; despite they have a high technical competence and good infrastructure. In order to solve the problem, direction and goal of researches and developments should be clear. The domestic golf industry organizations have focused on the short-term profits and did not pursue in-depth scientific researches. Therefore, it is needed to make long-term plans which are comprehensive and systematic to strengthen the competitiveness. In this study, authors incorporate nanomaterials to golf shafts as high-end technology and suggest strategies to promote competitiveness through the nano-technology, effective planning and management.