스마트 재료를 통해 나타나는 디자인 적용 및 표현 특성 분석 -스마트 표면을 중심으로-

손혜희 ( Hye Hee Son ),최경실 ( Gyoung Sil Choi ) 디자인융복합학회 2012 디자인융복합연구 Vol.11 No.4

This study focuses on the concepts and the technological aspects of the ‘Smart Material’. Also, it scrutinizes the applications and the traits in the expression of the space design on the ‘Smart surfaces’. The purpose of this paper is to apply to the practical design step the combination of the recent advances in technologies and the aesthetic interests, both in terms of the new materials. The SM is trans materials and responsive materials in that it dynamic and convergence conforms and reacts to the external stimulus. The Smart surface is reacts to the external stimulus, one of which is the environmental and the other is the human stimulus. The functional traits accompany the variability of space, vision control, communication, energy efficiency and the expressive traits include shape transformation and color and light changing. Therefore, the SM serves as one of the key design elements that comprises the depth of the surface as it resolves the environmental issues, and stimulates the aesthetical as well as emotional aspects. Thus, the SM should be considered as one of the most fundamental elements in configuring the surface stimuli. The blueprints of the SM should precede such design mainly to avoid the absolute effect of the vision when in contact with the surface, discoving the essence and potentials of the material in turn.

Chemical Sensors Based on Distributed Bragg Reflector Porous Silicon Smart Particles

Sohn, Honglae The Basic Science Institute Chosun University 2015 조선자연과학논문집 Vol.8 No.1

Sensing characteristics for porous smart particle based on DBR smart particles were reported. Optically encoded porous silicon smart particles were successfully fabricated from the free-standing porous silicon thin films using ultrasono-method. DBR PSi was prepared by an electrochemical etch of heavily doped $p^{++}$-type silicon wafer. DBR PSi was prepared by using a periodic pseudo-square wave current. The surface-modified DBR PSi was prepared by either thermal oxidation or thermal hydrosilylation. Free-standing DBR PSi films were generated by lift-off from the silicon wafer substrate using an electropolishing current. Free-standing DBR PSi films were ultrasonicated to create DBR-structured porous smart particles. Three different surface-modified DBR smart particles have been prepared and used for sensing volatile organic vapors. For different types of surface-modified DBR smart particles, the shift of reflectivity mainly depends on the vapor pressure of analyte even though the surfaces of DBR smart particles are different. However huge difference in the shift of reflectivity depending on the different types of surface-modified DBR smart particles was obtained when the vapor pressures are quite similar which demonstrate a possible sensing application to specify the volatile organic vapors.

Chemical Sensors Based on Distributed Bragg Reflector Porous Silicon Smart Particles

손홍래 조선대학교 기초과학연구원 2015 조선자연과학논문집 Vol.8 No.1

Sensing characteristics for porous smart particle based on DBR smart particles were reported. Optically encoded poroussilicon smart particles were successfully fabricated from the free-standing porous silicon thin films using ultrasono-method. DBR PSi was prepared by an electrochemical etch of heavily doped p++-type silicon wafer. DBR PSi was prepared byusing a periodic pseudo-square wave current. The surface-modified DBR PSi was prepared by either thermal oxidationor thermal hydrosilylation. Free-standing DBR PSi films were generated by lift-off from the silicon wafer substrate usingan electropolishing current. Free-standing DBR PSi films were ultrasonicated to create DBR-structured porous smartparticles. Three different surface-modified DBR smart particles have been prepared and used for sensing volatile organicvapors. For different types of surface-modified DBR smart particles, the shift of reflectivity mainly depends on the vaporpressure of analyte even though the surfaces of DBR smart particles are different. However huge difference in the shiftof reflectivity depending on the different types of surface-modified DBR smart particles was obtained when the vaporpressures are quite similar which demonstrate a possible sensing application to specify the volatile organic vapors.

스마트폰을 이용한 실시간 표면영상유속계 개발

류권규,황정근 한국수자원학회 2016 한국수자원학회논문집 Vol.49 No.6

본 연구는 안드로이드 기반의 스마트폰을 이용한 실시간 표면영상유속계를 개발하는 것이다. 스마트폰이 내장한 카메라, GPS, 방향 센서, CPU를 활 용하여, 실시간으로 현장에서 하천의 표면유속을 측정하는 것이다. 먼저, 스마트폰의 GPS를 이용하여 측정 현장의 위치를 파악하고, 경사계(방향 센 서)를 활용하여 카메라와 촬영면의 기하적인 관계를 설정한다. 이 때 입력해야 할 유일한 변수는 수면과 카메라의 연직 높이뿐이다. 내장된 카메라로 정해진 시간만큼 동영상을 촬영한다. 촬영된 동영상을 개방 소스의 영상처리 라이브러리인 OpenCV를 이용하여 프레임별로 분할하고, 이를 시공간 영상 분석하여 하천 표면의 2차원 유속장을 추정한다. 시판되는 안드로이드 스마트폰에 적용하여 현장 시험한 결과 약 11초에 1회의 순간유속 측정 (1 초간의 평균유속 측정)을 할 수 있어, 현장에서 즉각적으로 하천 수표면의 표면유속을 측정할 수 있었다. 또한 이 순간유속을 수십회 반복한 뒤 평균하 여 시간평균유속을 구할 수 있었다. 개발된 시스템을 실험 수로에서 시험한 결과, 측정이 매우 효과적이며 편리하였다. 측정된 결과를 프로펠러 유속계 에 의한 측정값과 비교한 결과, 최대 오차 13.9%, 평균적으로 10%이내의 오차로 실험 수로의 표면 유속을 측정할 수 있었다. The present study aims to develop a real-time surface image velocimeter (SIV) using an Android smartphone. It can measure river surface velocity by using its built-in sensors and processors. At first the SIV system figures out the location of the site using the GPS of the phone. It also measures the angles (pitch and roll) of the device by using its orientation sensors to determine the coordinate transform from the real world coordinates to image coordinates. The only parameter to be entered is the height of the phone from the water surface. After setting, the camera of the phone takes a series of images. With the help of OpenCV, and open source computer vision library, we split the frames of the video and analyzed the image frames to get the water surface velocity field. The image processing algorithm, similar to the traditional STIV (Spatio-Temporal Image Velocimeter), was based on a correlation analysis of spatio-temporal images. The SIV system can measure instantaneous velocity field (1 second averaged velocity field) once every 11 seconds. Averaging this instantaneous velocity measurement for sufficient amount of time, we can get an average velocity field. A series of tests performed in an experimental flume showed that the measurement system developed was greatly effective and convenient. The measured results by the system showed a maximum error of 13.9 % and average error less than 10 %, when we compared with the measurements by a traditional propeller velocimeter.

접촉 작동식 기기(승강기 버튼, 현금인출기, 스마트폰) 표면에 존재하는 미생물의 분리, 계수 및 동정

김지은(Ji Eun Kim),이은빈(Eun Bin Lee),양윤정(Yun Jeong Yang),김우형(Woo Hyeong Kim),오정민(Jung Min Oh),임대용(Dae Yong Lim),박예닮(Ye Darm Park),최민석(Min Suk Choi),이채영(Chae Young Lee),안연수(Yeon Soo An),송학진(Hak Jin Song),윤 대한환경공학회 2019 대한환경공학회지 Vol.41 No.8

목적: 본 연구에서는 다수의 사람이 손끝으로 작동시키는 각종 접촉 작동식 기기의 접촉부에 존재하는 세균을 계수 및 분리하였으며 이들 중 배양이 가능한 세균을 16S rRNA 분석을 통하여 동정하였다. 이 과정을 통하여 각종 기기의 표면에 존재하는 세균의 수와 종류를 확인하고 존재하는 세균의 다양성과 위험성을 확인하고자 하였다. 방법: 공공건물(10층 기준)의 승강기 버튼과 시중 은행의 현금인출기 표면 및 스마트폰 표면에서 시료를 채취하여 분석하였다. 세균의 수는 시료를 다단 희석한 후 LB agar에 도말하여 CFU (Colony Forming Unit)를 확인하였으며, 분리된 세균의 동정은 16S rRNA분석을 통하여 진행하였다. 또한 많은 CFU가 확인된 시료는 별도의 DGGE(Denaturing Gradient Gel Electrophoresis) 분석을 실시하여 다양한 세균종의 분포를 확인하였다. 결과 및 토의: 채취된 시료의 분석 결과, 승강기 버튼에서 가장 높은 CFU가 확인되었다(평균 163±17 CFU/㎠). 또한 스마트폰 화면과 현금인출기 화면에서는 1 ㎠ 당, 각각 평균 66±13 CFU 및 6 ± 1 CFU가 검출되었다. 전체 시료 중 세균이 검출되지 않은 시료는 없었으며, 세 종류의 기기에서 모두 병원성 미생물이 발견되었다. 또한 DGGE 분석결과, 모든 기기의 시료에서 LB배지에서의 배양보다 많은 수의 미생물종이 확인되었다. 특히 현금인출기의 표면에서 측정된 CFU와 DGGE의 결과에서 많은 차이가 발생하였다. 이는 각각의 환경에 존재하는 세균종의 배양에 필요한 최적 환경이 다름에 기인한 것으로 보인다. 결론: 본 연구의 결과, 사람의 접촉이 잦은 기기의 표면에는 다양한 종류의 병원성 미생물이 존재함을 확인했으며, 이는 병원성 세균의 전달에 의한 감염에 사용자들이 노출될 수 있음을 보여준다. 따라서 면역력이 떨어지는 어린이, 임산부, 환자 및 노인의 경우, 각종 접촉 작동식 기기의 사용 전・후에는 충분한 위생에 대한 주의가 필요하다고 판단된다. Objectives : The purpose of this study was to identify and isolate bacteria on the surface of elevator buttons, ATM screens, and smartphone surfaces. Through this process, bacterial diversity and presence of pathogens on the surface were evaluated for the prospective public health and environment. Methods : Bacterial samples collected from elevator buttons, ATM screen surfaces, and smartphone surfaces were analyzed their CFUs using LB agar plates. Unique colonies in the plates were isolated and identified by the 16S rRNA analysis. The diversity of the bacteria in the collected samples containing high number of CFU was monitored using the Denaturing Gradient Gel Electrophoresis (DGGE). Results and Discussion : Among the instrument surfaces, the elevator buttons showed the highest CFU (average: 163±17 CFU/㎠). The samples from smartphone and ATM surfaces have 66±13 and 6 ± 1 CFU, respectively. The CFU analysis also showed that the all collected samples had active bacterial species, and the 16S rRNA analysis indicated that pathogenic bacteria were existed on the surface on the buttons and screens. The DGGE analysis showed that higher diversity of bacterial species were found compare to the CFU analysis of the samples. This difference in the bacterial diversity is probably due to the difference in optimal cultivation conditions of each bacterial species in the samples. Conclusions : The user interfaces of the elevators, ATMs, and smartphones contained high diversity of normal and pathogenic bacterial species. Thus attention must be paid to the transfer of pathogenic bacteria in children, pregnant women, immunocompromised patients.

A Collecting Machine Design for Oil Slick

Chunhui Lu 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.12

Oil spill accidents are likely to increase in three decades. An oil spill accident can lead to serious crisis to the marine environment. The wastewater and waste sludge all contains oil in the process of petroleum mining. The oil slick can move or transfer by spread, evaporate, dissolve, emulsifying, photolysis, and biodegradation and absorption which can pollute air, water and soil and is a disaster to the environment. The research analysis shows the oil slick flow with surface wave in wind and finds a few characteristics can help the design. A new collecting machine which can collect the oil slick efficient is designed by adjusting its position in the surface wave. The design includes three main parts of machine while the collecting plate is keeping under the wave but squeeze water surface. All the machine parts shall be controlled with a flexible smart system to adapt the changing surface wave in the ocean.

Micro-AAJ를 이용한 엔진 피스톤 링의 마찰 저감 표면 개발

최수창(Soochang Choi),노승국(Seung-Kook Ro),이현화(Hyun-Hwa Lee),박종권(Jong-Kweon Park) Korean Society for Precision Engineering 2014 한국정밀공학회지 Vol.31 No.5

In this paper, we report a new manufacturing method for friction reduction using micro-AAJ (abrasive air-jet) machining. AAJ machining employs compressed air to accelerate a jet of highspeed particles to mechanically machine features, including micro-channels and micro-holes, into glass, metal, or polymer substrates for use in microfluidics, MEMS (micro electromechanical systems). And we introduce the micro-AAJ machining system, which consists of a micro-AAJ nozzle and a five-axis positioning system. Various micro-AAJ nozzles can be used, depending on the required surface structure, and three-dimensional machining is possible. We machined samples under six different conditions and describe machining results obtained while using it. We also measured the coefficient of friction of micro-textured surfaces. We report the coefficient of friction of micro-textured surfaces patterned using micro-AAJ machining for engine piston ring.

Hardware-In-the-Loop Simulation Test for Actuator Control System of Smart UAV

Chang-sun Yoo,Young-shin Kang,Bum-jin Park 제어로봇시스템학회 2010 제어로봇시스템학회 국제학술대회 논문집 Vol.2010 No.10

The Smart UAV is the tilt rotor type of unmanned aerial vehicle that has been developed by KARI since 2002. According to the characteristics of tilt rotor aircraft, it has a flight envelope of VTOL(vertical take-off and landing) and high cruise speed. Because the conversion flight between helicopter and airplane mode is required, the actuator system of Smart UAV control surfaces has 12 actuators and 5 controllers for nacelle tilt as well as flaperon, elevator and rotor. Based on Fly-By-Wire system, all actuators except for elevator are an electric linear type with dual motors and RVDT sensors. Actuators for elevator are an electric rotary type with single motor and are equipped on each control surface of two elevators. Controllers for activating actuators were developed in domestic company by interfacing with flight control computer through ARINC 429 and with actuators through analog cable. To accomplish the safe conversion flight between helicopter and airplane mode, a role change of control surfaces according to tilting angle is also required on time. This requires the high reliable and accurate performance for actuator system that consists of actuators, controllers and flight control computer. Prior to actual flight test, this actuator control system was tested and evaluated by Hardware-In-Loop(HIL) simulation on the ground. This paper describes the configuration of actuator control system and HILS system of Smart UAV and gives the results of HILS test.

가스질화처리 적용을 통한 스마트무인기 머레이징강 로터허브 부품 품질개선

이명규,최성욱,김재무,Lee, Myeong Kyu,Choi, Seong Wook,Kim, Jai Moo 항공우주시스템공학회 2014 항공우주시스템공학회지 Vol.8 No.2

Feathering spindle is one of the critical parts of the rotor system in the Smart Unmanned Aerial Vehicle(SUAV) that it was manufactured with special material, Maraging C300. During the initial ground and tie-down flight tests of the SUAV, surface of the feathering spindle contacting to the needle-roller bearings showed excessive wear and dent due to high vibrating loads transferred from the rotating blades. Gas nitriding process was applied to the bearing contact surface of the feathering spindle to increase surface hardness so as to improve the surface defects. This paper briefly presents the gas nitriding process adopted and the spindle quality improvements including wear and corrosion resistance.

Surface and small scale effects on the dynamic buckling of carbon nanotubes with smart layers assuming structural damping

Ahmad Farokhian,Mehdi Salmani-Tehrani 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.37 No.2

In this paper, dynamic buckling of a smart sandwich nanotube is studied. The nanostructure is composed of a carbon-nanotube with inner and outer surfaces coated with ZnO piezoelectric layers, which play the role of sensor and actuator. Nanotube is under magnetic field and ZnO layers are under electric field. The nanostructure is located in a viscoelastic environment, which is assumed to obey Visco-Pasternak model. Non-local piezo-elasticity theory is used to consider the small-scale effect, and Kelvin model is used to describe the structural damping effects. Surface stresses are taken into account based on Gurtin-Murdoch theory. Hamilton principle in conjunction with zigzag shear-deformation theory is used to obtain the governing equations. The governing equations are then solved using the differential quadrature method, to determine dynamic stability region of the nanostructure. To validate the analysis, the results for simpler case studies are compared with others reported in the literature. Then, the effect of various parameters such as small-scale, surface stresses, Visco-Pasternak environment and electric and magnetic fields on the dynamic stability region is investigated. The results show that considering the surface stresses leads to an increase in the excitation frequency and the dynamic stability region happens at higher frequencies.