• Journal of Astronomy and Space Sciences
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• v.30 no.4
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• pp.335-344
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• 2013

TRiplet Ionospheric Observatory-CubeSat for Ion, Neutron, Electron & MAgnetic fields (TRIO-CINEMA) is a CubeSat with 3.14 kg in weight and 3-U ($10{\times}10{\times}30$ cm) in size, jointly developed by Kyung Hee University and UC Berkeley to measure magnetic fields of near Earth space and detect plasma particles. When a satellite is launched into orbit, it encounters ultra-high vacuum and extreme temperature. To verify the operation and survivability of the satellite in such an extreme space environment, experimental tests are conducted on the ground using thermal vacuum chamber. This paper describes the temperature control device and monitoring system suitable for CubeSat test environment using the thermal vacuum chamber of the School of Space Research, Kyung Hee University. To build the chamber, we use a general purpose thermal analysis program and NX 6.0 TMG program. We carry out thermal vacuum tests on the two flight models developed by Kyung Hee University based on the thermal model of the TRIO-CINEMA satellite. It is expected from this experiment that proper operation of the satellite in the space environment will be achieved.

• Journal of Astronomy and Space Sciences
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• v.29 no.1
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• pp.23-31
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• 2012

Thermal analysis and control design are prerequisite essential to design the satellite. In the space environment, it makes satellite survive from extreme hot and cold conditions. In recent years CubeSat mission is developed for many kinds of purpose. Triplet Ionospheric Observatory (TRIO)-CubeSat for Ion, Neutral, Electron, MAgnetic fields (CINEMA) is required to weigh less than 3 kg and operate on minimal 3 W power. In this paper we describe the thermal analysis and control design for TRIO-CINEMA mission. For this thermal analysis, we made a thermal model of the CubeSat with finite element method and NX6.0 TMG software is used to simulate this analysis model. Based on this result, passive thermal control method has been applied to thermal design of CINEMA. In order to get the better conduction between solar panel and chassis, we choose aluminum 6061-T6 for the material property of standoff. We can increase the average temperature of top and bottom solar panels from $-70^{\circ}C$ to $-40^{\circ}C $ and decrease the average temperature of the magnetometer from $+93^{\circ}C$ to $-4^{\circ}C$ using black paint on the surface of the chassis, inside of top & bottom solar panels, and magnetometer.

• Journal of KIISE:Software and Applications
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• v.30 no.7_8
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• pp.610-617
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• 2003

Similarity matching in video database is of growing importance in many new applications such as video clustering and digital video libraries. In order to provide efficient access to relevant data in large databases, there have been many research efforts in video indexing with diverse spatial and temporal features. however, most of the previous works relied on sequential matching methods or memory-based inverted file techniques, thus making them unsuitable for a large volume of video databases. In order to resolve this problem, this paper proposes an effective and scalable indexing technique using a trie, originally proposed for string matching, as an index structure. For building an index, we convert each frame into a symbol sequence using a window order heuristic and build a disk-resident trie from a set of symbol sequences. For query processing, we perform a depth-first search on the trie and execute a temporal segmentation. To verify the superiority of our approach, we perform several experiments with real and synthetic data sets. The results reveal that our approach consistently outperforms the sequential scan method, and the performance gain is maintained even with a large volume of video databases.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.117.1-117.1
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• 2012

Energetic neutral atoms (ENAs) are emitted by charge exchange collisions between energetic ions and cold neutral atoms. ENAs can be used as an alternative measure of the energetic ions in the source region because they maintain the energy and pitch angle of the source energetic ions. In the present study we present simulation results of the ENA emissions during a magnetic storm to be measured by the STEIN instrument onboard the CINEMA/TRIO satellites. The CINEMA/TRIO mission consists of three identical cubesats with low-altitude orbits. The STEIN instrument onboard each cubesat can measure ENAs with energies from ~4 keV to ~20 keV as well as suprathermal electrons and ions. The measurement of ENA emissions from ring current by STEIN is simulated using the models for energetic ring current ions and geocoronal neutral atoms. Especially we will discuss about the energy spectrum of the ENAs and the effect of transient variations of the ring current.

• Journal of Korean society of Dental Hygiene
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• v.12 no.3
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• pp.611-620
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• 2012

Objectives : This study evaluated the changes in surface roughness of denture base resin according to the types of denture cleansers. Methods : A denture base resin(Vertex RS, Dentimax, Netherland) was used. Two toothpaste(Antiplaque, Bukwang, Korea; 2080, Aekyung, Korea) and a kitchen detergent(Trio, Aekyung, Korea) were used as a denture cleanser. The specimens were put on the V8 crossbrushing machine(Sabri enterprises, Downers grove, IL, USA) to reproduce toothbrushing and the toothbrushes were flat, round end and soft type. The surfaces of denture base resin specimens were observed by profilometer(SJ-400, MITUTOYO, Japan) and SEM(S-3000N, Hitachi Co., Ibaraki, Japan). Results : 1. According to the result of measuring surface roughness, there was statistically significant difference in Ra, Rq, and Rz(p<0.05). 2. As for Ra, Rq and Rz, Antiplaque toothpaste showed the highest roughness, and there was significant difference from other groups(p<0.01). 2080 toothpaste, Trio, and distilled water were classified as the same group. 3. According to the result of observation with the SEM, the surfaces of the Antiplaque toothpaste group after toothbrushing showed the greatest roughness, and the surfaces of 2080 toothpaste, Trio, and distilled water groups were rough in order. Trio and distilled water had the surfaces similar to those before toothbrushing. Conclusions : Studies to compare the efficacy of denture management methods and examine the effects of denture cleansers on denture materials will be helpful for dental hygienists and dentists providing patients with proper information and education. And it will be also useful for denture users' oral health.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.11
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• pp.912-917
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• 2001

In this study, we define the measuring method of crank angle precisely using an event and perform a study on the hardware structure and software algorithms which is applicable for the commercial engine. Also we developed a Computer-ECU(Personal computer based electronic control unit) using a computer and a microprocessor, for performing the ignition at a desire position(angle) and for controlling a duty ratio a pulse for ISC(Idle speed control). We applied these algorithms to the modeling which is induced a concept of event and got a better result than a conventional ECU in the state of transient as a result of performing air fuel ratio control in a commercial engine. This technique can be used for the back to improve ECU performance. It the present type of Hybrid I. C voltage regulator is altered to the new type of regulator, we will be surely able to reduce the production cost as well as simplify the design of alternator\`s rear bracket and rectifier part because of the removal of trio diode. Experiment is taken by MS-R004.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.199.1-199.1
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• 2012

TRIO-CINEMA(TRiplet Ionospheric Observatory-Cubesat for Ion, Neutron, Electron & MAgnetic field)는 지구근접공간에서의 미세 자기장 변화 및 중성입자의 검출을 목적으로 경희대학교와 UC Berkeley가 공동 개발하는 초소형위성이다. 초소형위성은 내부 공간이 협소하여 효율적인 공간배치 및 위성체발사 시 진동에도 견딜 수 있도록 harness가 제작되어야 한다. CINEMA는 OBC, EPS, 배터리, 수신기, IIB(Instrument Interface Board), MAGIC(MAGnetometer Imperial College) board, HVPS(High Voltage Power Supply)로 구성된 avionics bus와 MAGIC, STEIN(Supra Thermal Electron, Ion, Neutral)의 payload, Solar panel, UHF와 S-band 안테나로 구성되어 있다. Solar panel에서 생산된 전력은 EPS를 통해 배터리에 저장되고 PC104를 통해 avionics stack의 각 board로 전력이 분배된다. IIB는 탑재체 파트와 연결되어 이를 제어하고 HVPS에서 STEIN에 공급되는 고전압은 특수 와이어를 통해 연결되며 UHF 안테나와 S-band 안테나는 RF 케이블로 수신기와 송신기가 연결되어 있다. 각각의 harness는 케이블타이와 lacing tape로 위성체와 고정되며 커넥터는 고정 지지대를 제작하여 나사로 체결하였다. CINEMA에 적용된 harness는 진동시험과 열진공시험을 통해 harness와 시스템의 안정성이 검증 되었다.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06a
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• pp.397-399
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• 2006

본 논문은 IP주소로 파악한 사용자의 지역정보를 이용하여 응용서비스를 제공하는 시스템에 관한 것으로 대량의 검색 질의를 하는 포털사이트에 최적화된 서비스를 하기 위하여 검색속도를 향상시킬 수 있는 데이터 구조를 적용한다. IP주소를 이용한 지역위치정보 검색시스템은 array를 이용한 flag, hashing을 이용한 cache, trio, 메모리 database 등의 자료구조를 이용하여, 각각을 실험을 통해 검색성능 향상에 미치는 영향을 평가한다.

• Journal of KIISE:Information Networking
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• v.32 no.4
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• pp.543-550
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• 2005

Demand for better services in the Internet has been increasing due to the rapid growth of the Internet, and hence next generation routers are required to perform intelligent packet classification. For a given classifier defining packet attributes or contents, packet classification is the process of identifying the highest priority rule to which a packet conforms. A notable characteristic of real classifiers is that a packet matches only a small number of distinct source-destination prefix pairs. Therefore, a lot of schemes have been proposed to filter rules based on source and destination prefix pairs. However, most of the schemes are based on sequential one-dimensional searches using trio which requires huge memory. In this paper, we proposea memory-efficient two-dimensional search scheme using source and destination prefix pairs. By constructing binary prefix tree, source prefix search and destination prefix search are simultaneously performed in a binary tree. Moreover, the proposed two-dimensional binary prefix tree does not include any empty internal nodes, and hence memory waste of previous trio-based structures is completely eliminated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1201-1207
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• 1999

To utilize the leaves of broccoli, the shape of which was similar with that of kale leaves, as a vegetable juice, the extracts from two types of vegetable leaves were subjected to the analyses of proximate com ponents, volatile sulfur compounds, vitamin C and minerals. The sensory evaluation of the juices, prepared from kale and broccoli leaves, were performed by duo trio test and scoring test. Among eight varieties of broccoli, four varieties('Pilgrim', 'Greenbelt', 'Salinas' and 'Shasta')were not significantly different from kale(p<0.05), based on the duo trio sensory test. Sulfur and nitrogen compounds present in the dichloromethane extracts of kale and broccoli leaves 'Pilgrim' were identified as 3 butenyl, allyl, butyl and 4 methylsulfinylbutyl isothiocyanate(sulforaphane), 4,5 epithiovalero, 4,5 epithio 3 hydroxyvalero, benzenepropane, 3 hydroxy 4 propene, 4 methylthio butane, 3 hydroxy 3 phenylpropane, 5 methy lsulfinylpentane, 4 methoxyphenyl 3 hydroxypropane nitrile and dimethyl trisulfide by GC/MSD analysis. Proximate components were observed to be relatively similar between kale and broccoli leaves. Vitamin C and sugar content were higher in broccoli leaves(125∼180mg% and 8∼12°Brix) than in kale(101mg% and 7oBrix). In mineral analysis by AA and ICP Mass, 'Pilgrim' showed a higher content of K, Fe, Mn, Zn and Se. In separate experiment, sensory scores of bitter taste and astringent taste were lower and scores of over all taste and over all acceptability, higher in broccoli('1243') juice than those in kale juice.