• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.4 s.247
• /
• pp.373-378
• /
• 2006

We present the design, fabrication, and characterization of a multi-chip microelectrofluidic bench, achieving both electrical and fluidic interconnections with a simple, low-loss and low-temperature electrofluidic interconnection method. We design 4-chip microelectrofluidic bench, having three electrical pads and two fluidic I/O ports. Each device chip, having three electrical interconnections and a pair of two fluidic I/O interconnections, can be assembled to the microelectofluidic bench with electrical and fluidic interconnections. In the fluidic and electrical characterization, we measure the average pressure drop of $13.6{\sim}125.4$ Pa/mm with the nonlinearity of 3.1 % for the flow-rates of $10{\sim}100{\mu}l/min$ in the fluidic line. The pressure drop per fluidic interconnection is measured as 0.19kPa. Experimentally, there are no significant differences in pressure drops between straight channels and elbow channels. The measured average electrical resistance is $0.26{\Omega}/mm$ in the electrical line. The electrical resistance per each electrical interconnection is measured as $0.64{\Omega}$. Mechanically, the maximum pressure, where the microelectrofluidic bench endures, reaches up to $115{\pm}11kPa$.

• Geomechanics and Engineering
• /
• v.13 no.5
• /
• pp.715-742
• /
• 2017

Earth berms are often left in place to support retaining walls or piles in order to eliminate horizontal struts in excavations of soft soil areas. However, if the excavation depth is relatively large, an earth berm-supported retaining system may not be applicable and could be replaced by a multi-bench retaining system. However, studies on multi-bench retaining systems are limited. The goal of this investigation is to study the deformation characteristics, internal forces and interaction mechanisms of the retaining structures in a multi-bench retaining system and the failure modes of this retaining system. Therefore, a series of model tests of a two-bench retaining system was designed and conducted, and corresponding finite difference simulations were developed to back-analyze the model tests and for further analysis. The tests and numerical results show that the distance between the two rows of retaining piles (bench width) and their embedded lengths can significantly influence the relative movement between the piles; this relative movement determines the horizontal stress distribution in the soil between the two rows of piles (i.e., the bench zone) and thus determines the bending moments in the retaining piles. As the bench width increases, the deformations and bending moments in the retaining piles decrease, while the excavation stability increases. If the second retaining piles are longer than a certain length, they will experience a larger bending moment than the first retaining piles and become the primary retaining structure. In addition, for varying bench widths, the slip surface formation differs, and the failure modes of two-bench retained excavations can be divided into three types: integrated failure, interactive failure and disconnected failure.

• Journal of the Korea Furniture Society
• /
• v.23 no.1
• /
• pp.75-83
• /
• 2012

Space dominates all the art activities human do and plays a role of providing aesthetic emotion. Architecture, sculpture, painting, and furniture, etc. these two and three dimensional works are represented in space and interpreted the role of its form, structure and function. Each area is different, but space has been studied in philosophy, physics, geometry, and mathematical studies, etc. and has been consistently interpreted and represented relating to a variety of human creative activity. Furniture is also three dimensional art being dependent on space. In the United States in 2004, I made the living room bench by applying the spatial concept at Rochester Institute of Technology. Two years later, this design was adopted by wendell Castle Collection, an American furniture company, then prototype were made and tested three times during a year, and then since 2007 as indoor benches it has been manufactured in the United States. The study's purpose is to order the process of its development based on the experience of bench production applied the spatial concept, and by analyzing the properties of spatial concept, I am planning to propose a new concept on interaction with the space and furniture for next.

• Journal of Bio-Environment Control
• /
• v.32 no.2
• /
• pp.132-138
• /
• 2023

The Gymnocalycium mihanovichii has been an important export item of Korean flower industry for a long time. Although there is a high demand for grafted cactus from overseas, its production for export is limited. In this study, the growth and marketable yield characteristics of Gymnocalycium mihanovichii 'I-Hong' were compared between soil culture and ebb-and-flow hydroponic system with single- or double-tier bench. As a result, hydroponic methods with single-tier bench resulted in higher fresh weight and glove diameter compared to other cultivation methods. In the ebb-and-flow hydroponic system, hydroponic system with double-tier bench of grafted cactus traits has a lower growth rate than other cultivations. However, the hydroponic system with double-tier bench of grafted cactus significantly increased the yield. In conclusion, the yield from hydroponic system with double-tier bench was better than soil cultivation method. Although there were some differences in color depending on the cultivation method, it was considered that there was no difference in appearance of Gymnocalycium mihanovichii 'I-Hong'. Our results suggest the cultivation methods to overcome production constraints, expand their exports, and improve the value-added characteristics of grafted cactus.

• Tribology and Lubricants
• /
• v.13 no.4
• /
• pp.33-39
• /
• 1997

In order to establish a new temperature criterion to prevent the pistons from ring sticking due to deposit formation, bench test and engine test were performed. The effects of oil degradation and temperature on deposit formation was studied by a modified panel coking test. Oil degradation was analyzed by FTIR. Oil oxidation and nitration were selected as a factors to evaluate oil degradation. Bench test results show that oil oxidation is more effective to the deposit formation than oil nitration. And the temperature increase accelerates deposit formation and deposit formation increase rapidly above 26$0^{\circ}C$. Especially, in case of degraded oil, the deposit formation increases so rapidly that ring sticking can occur. The effect of piston temperature on the deposit formation was confirmed by engine test.

• Journal of Practical Engineering Education
• /
• v.7 no.1
• /
• pp.25-30
• /
• 2015

Virtual reality is a combination of various studies, such as programming, simulation, and computer graphics. This type of new cultural paradigm requires novel concept of contents development and information exchange. This research uses 3D virtual reality technology in new equipment called I-Bench Mobile which let user to interact with the equipment for completing furniture disposition task. The simulation is manufactured in 3D with application of physics, and the ultimate goal of it is to increase customers' satisfaction by allowing them to enjoy snap shot function for arranging furniture at exact desired place. This research requires not only coding techniques but also educating process in both engineering and art, such as computer science, media art design, and visual communication; therefore, the development of software by facilitating Virtual/Augmented Reality technology in this research is a good example of fusion IT technique education.

• Journal of KIISE
• /
• v.42 no.2
• /
• pp.169-176
• /
• 2015

The atomic write technique is a good solution to solve the problem of the double write buffer. The atomic write technique needs modified I/O subsystems (i.e., file system and I/O schedulers) and a special SSD that guarantees the atomicity of the write request. In this paper, we propose the writing unit aligned block allocation technique (for EXT4 file system) and the merge prevention of requests technique for the CFQ scheduler. We also propose an atomic write-supporting SSD which stores the atomicity information in the spare area of the flash memory page. We evaluate the performance of the proposed atomic write scheme in MariaDB using the tpcc-mysql and SysBench benchmarks. The experimental results show that the proposed atomic write technique shows a performance improvement of 1.4~1.5 times compared to the double write buffer technique.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.36 no.5
• /
• pp.475-479
• /
• 2012

We present a novel polymer fabrication process involving direct UV patterning of a hyperbranched polymer, AEO3000. Compared to PDMS, which is the most widely used polymer in bioMEMS devices, the present polymer has advantages with regard to electrode integration and fast fabrication. We designed a four-chip microelectrofluidic bench having three electrical pads and two fluidic I/O ports. We integrated a microfluidic mixer and a cell separator on the bench to characterize the interconnection performance and sample manipulation. Electrical and fluidic characterization of the microfluidic bench was performed. The measured electrical contact resistance was $0.75{\pm}0.44{\Omega}$, which is small enough for electrical applications, and the pressure drop was 8.3 kPa, which was 39.3% of the value in the tubing method. By performing yeast mixing and a separation test in the integrated module on the bench, we successfully showed that the interconnected chips could be used for bio-sample manipulation.

• Journal of Mechanical Science and Technology
• /
• v.16 no.11
• /
• pp.1457-1469
• /
• 2002

This paper is the first of several companion papers, which investigate axial stratification process and its effects in an Sl engine. The axial stratification is very sophisticate phenomenon, which results from combination of fuel injection, port and in-cylinder flow and mixing. Because of the inherent unsteady condition in the reciprocating engine, it Is impossible to understand the mechanism through the analytical method. In this paper, the ports were characterized by swir and tumble number in steady flow bench test. After this, lean misfire limit of the engines, which had different port characteristic, were investigated as a function of swirl ratio and injection timing for confirming the existence of stratification. In addition, gas fuel was used for verifying whether this phenomenon depends on bulk air motion of cylinder or on evaporation of fuel. High-speed gas sampling and analysis was also performed to estimate stratification charging effect. The results show that the AFR at the spark plug and LML are very closely related and the AFR is the results of bulk air motion.

• Journal of information and communication convergence engineering
• /
• v.11 no.2
• /
• pp.112-117
• /
• 2013

In order to reuse a register transfer level (RTL)-based IP block, it takes another architectural exploration in which the RTL will be put, and it also takes virtual platforms to develop the driver and applications software. Due to the increasing demands of new technology, the hardware and software complexity of organizing embedded systems is growing rapidly. Accordingly, the traditional design methodology cannot stand up forever to designing complex devices. In this paper, I introduce an electronic system level (ESL)-based approach to designing complex hardware with a derivative of SystemVerilog. I adopted the concept of reuse with higher levels of abstraction of the ESL language than traditional HDLs to design multiplication server farms. Using the concept of ESL, I successfully implemented server farms as well as a test bench in one simulation environment. It would have cost a number of Verilog/C simulations if I had followed the traditional way, which would have required much more time and effort.