• Title/Summary/Keyword: space experiment

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Analysis on the Growth Environment of Disporum smilacinum A. GRAY for Development of Shade-tolerance Groundcover Plant (내음성 지표식물 개발을 위한 애기나리의 생육환경분석)

  • 이기철;박슬기
    • Journal of the Korean Institute of Landscape Architecture
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    • v.19 no.2
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    • pp.65-74
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    • 1991
  • The purpose of this study was to find the basic application of Disporum genus in landscape-arc-hitectual space. Environment of native site (Daeducksan, Piseulsan) and growth characteristics of experiment plot were investigated and analyzed in this study. The results of this study were as follows; 1. In the case of environment of native site, the relative light intensity was about 10% and distribution of species were primarily north slope. Gradient of Daeducksan and Piseulsan were 10$^{\circ}$, 18$^{\circ}$ Soil textures was Lic both and field capacity of Daeducksan and Piseulsan were 69%, 73.5%. The soil pH of Daeducksan and Piseulsan were 6.1 and 5.8. The both content of organic matter and C.E.C. were high markedly. The P2O5 content of Daeducksan showed high but total nitrogen showed nearly the same level when comparing with the common dry field condition. 2. In tree layer, Daeducksan composed of broadleaved forest of 80% involving Quercus variabilis, and Piseulsan composed of coniferous forest of 80% involving Pinus densiflora on the other hand. Daeducksan, therefore, was more appearance species than Piseulsan in herbaceous layer. 3. Result in ANOVA Test, significance followed with light intensity was recognized in plant height, leaf width, leaf length, leaf thick and No. of leaf, while in the case of soil was not. Plant height was longest in 1% and leaf width, leaf length was largest in 25%. Therefore ornamental value of leaf was the very best in 25%. 4. Result in correlation coefficient analysis, plant height was correlated leaf width, leaf length. The longer plant height, the smaller leaf width, leaf length. In relative light intensity of 1%, flower was hardly expected because of the more shade, the less flower. Disporum smilacinum is expected great use as ground covers in the shades of tall-building or hdavy woods.

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Design of Push Agent Model Using Dual Cache for Increasing Hit-Ratio of Data Search (데이터 검색의 적중률 향상을 위한 이중 캐시의 푸시 에이전트 모델 설계)

  • Kim Kwang-jong;Ko Hyun;Kim Young-ja;Lee Yon-sik
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.6 s.38
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    • pp.153-166
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    • 2005
  • Existing single cache structure has shown difference of hit-ratio according to individually replacement strategy However. It needs new improved cache structure for reducing network traffic and providing advanced hit-ratio. Therefore, this Paper design push agent model using dual cache for increasing hit-ratio by reducing server overload and network traffic by repetition request of persistent and identical information. In this model proposes dual cache structure to do achievement replace gradual cache using by two caches storage space for reducing server overload and network traffic. Also, we show new cache replace techniques and algorithms which executes data update and delete based on replace strategy of Log(Size) +LRU, LFU and PLC for effectiveness of data search in cache. And through an experiment, it evaluates Performance of dual cache push agent model.

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AN ELECTRON MICROSCOPIC STUDY ON THE EFFECTS OF IRRADIATION ON THE BUCCAL MUCOSA OF RAT (방사선조사가 백서 협점막에 미치는 영향에 관한 전자현미경적 연구)

  • Choi Syng Kyu;Lee Sang Rae
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.17 no.1
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    • pp.7-20
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    • 1987
  • The author studied the acute reaction of cobalt-60 irradiation to buccal mucosa in rats and difference of the effects of single versus fractionated exposure. 195 Sprague Dowley strain rats, weighing about 120gm, were used in this experiment. 3 rats served as controls and the remaining 192 rats were divided into six groups of 32 rats each. Experimental group Ⅰ, Ⅱ, Ⅲ were received a single dose of 15Gy, 16.5Gy, 18Gy and group Ⅳ, Ⅴ, Ⅵ were received two equal sized fractionated dose of 9Gy, 9.75Gy, 10.5Gy at 4 hour intervals, respectively. The experimental groups were irradiated with cobalt-60 teletherapy unit, Picker model 4M 60 (Field size, 12x5 cm, SSD, 50㎝, Dose rate, 222cGy/min, Depth, 1㎝). The animals were sacrificed at 1, 2, 3, 6, 12 hours, 1, 3, 7 days after irradiation and the changes of the irradiated buccal mucosa were observed by electron and light microscopy. The results were as follows: 1. A single exposure was more damaging than fractionated exposure, and as the radiation dose increased, the changes of cell organelles became faster, but the healing of radiation-induced damage in fractionated exposure was faster than in single exposure. 2. The radiation-induced changes of the basal cells were the most prominent in 18Gy-single exposure group, and the least in 18Gy-fractionated exposure group. 3. Electron-microscopically, there appeared nuclear changes, swelling of mitochondria and rough endoplasmic reticulum, decrease of free ribosome, presence of vesicles, widening of intercellular space, and loss of basal lamina. The early remarkable changes were partly loss of nuclear membrane and swelling of mitochondria. 4. Light-microscopically, derangement and pyknosis of basal cells, hydropic changes of spinous cells, enlargement of granular cells, indistinctness of basement membrane, and proliferation of epithelium were observed.

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Implementation of the SLAM System Using a Single Vision and Distance Sensors (단일 영상과 거리센서를 이용한 SLAM시스템 구현)

  • Yoo, Sung-Goo;Chong, Kil-To
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.45 no.6
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    • pp.149-156
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    • 2008
  • SLAM(Simultaneous Localization and Mapping) system is to find a global position and build a map with sensing data when an unmanned-robot navigates an unknown environment. Two kinds of system were developed. One is used distance measurement sensors such as an ultra sonic and a laser sensor. The other is used stereo vision system. The distance measurement SLAM with sensors has low computing time and low cost, but precision of system can be somewhat worse by measurement error or non-linearity of the sensor In contrast, stereo vision system can accurately measure the 3D space area, but it needs high-end system for complex calculation and it is an expensive tool. In this paper, we implement the SLAM system using a single camera image and a PSD sensors. It detects obstacles from the front PSD sensor and then perceive size and feature of the obstacles by image processing. The probability SLAM was implemented using the data of sensor and image and we verify the performance of the system by real experiment.

Design of Radiation Hardened Shift Register and SEU Measurement and Evaluation using The Proton (내방사선용 Shift Register의 제작 및 양성자를 이용한 SEU 측정 평가)

  • Kang, Geun Hun;Roh, Young Tak;Lee, Hee Chul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.8
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    • pp.121-127
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    • 2013
  • Memory devices including SRAM and DRAM are very susceptible to high energy radiation particles in the space. Abnormal operation of the devices is caused by SEE or TID. This paper presents a method to estimate proton SEU cross section representing the susceptibility of the latch circuit that the unit cell of the SRAM and proposes a new latch circuit to mitigate the SEU. 50b shift register was fabricated by using the conventional latch and the proposed latch in $0.35{\mu}m$ process. Irradiation experiment was conducted at KIRAMS by using 43MeV proton beam. It was found that the proposed latch-shift register is not affected by the radiation environment compared to the conventional latch-shift register.

The Effect of Fashion Collage Program on Self-Identity and Creativity of College Students (패션콜라주 프로그램이 대학생의 자아정체감과 창의성에 미치는 영향)

  • Lee, Kyoung Hee;Lee, Seunghyun
    • Fashion & Textile Research Journal
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    • v.21 no.6
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    • pp.754-765
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    • 2019
  • The purpose of this study is to find out about the impact on self-identity and creativity of college students through the fashion collage program. The methods of research were content analysis and statistical analysis. The research subjects consisted of six fashion major college students experiment group and six control group students attending P university in Busan. The period of investigation was conducted once a week in the 9th session (2019. 04. 25. - 06. 18). The analysis criteria of fashion collage were divided into formality and contents, and the analysis criteria consisted of number of collage pieces, margin, overlapping, cut method, text position, color, space layout, and location of fashion design drawing. Collage maps were analyzed based on formal analysis, and fashion design drawings were analyzed based on formal and contents analysis. In order to verify the effectiveness of the fashion collage program, a pre-post test of self-identity and creativity was conducted. Statistical analysis was conducted by using the SPSS WIN 25.0 program, U-test of Mann-Whitney, Wilcoxon signed-rank test. In pre-post test of self-identity and creativity, there were significant differences. In conclusion, it has been shown that fashion collage programs are effective in improving self-identity and creativity for college students majoring in fashion. This study has a limitation of collage programs focused on self-discovery, so it should be carefully analyzed.

Performance Experiment and Evaluation of Water jet by the Explosives Position in Water-bag blasting using the Mist Guider (분무 가이더를 이용한 워터 백 기폭 시 폭약의 위치에 따른 분사 성능실험 및 평가)

  • Kim, Seung-Jun;Kim, Jung-Gyu;Ko, Young-Hun;Jung, Seung-Won;Baluch, Khaqan;Jin, Guochen;Yang, Hyung-Sik
    • Explosives and Blasting
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    • v.36 no.3
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    • pp.29-38
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    • 2018
  • With the recent industrial developments and economic development nationally, there has been a rapidly increasing demand for the use of underground space as locations for establishing social infrastructure and various convenience facilities. In this study, a mist-control system was developed to reduce the generation of dust in underground blasting. To enhance the dust-reduction effect, a guiding device was developed which is capable of adjusting the direction of the spray toward's the blasting face of mine or tunnel. A numerical analysis was performed by using the AUTODYN software, and results were compared with those published in basic experiments. To verify the mist-diffusion effect according to the position of explosives in a water bag, numerical analyses were conducted for the following cases: Explosives were set in the middle, and in the bottom of the water bag. The optimum condition was external detonation and center charge. The mist particle size from the result was suitable for the reduction of dust after blasting in underground mine and tunnel.

The Effects of Driving Rehabilitation Program on Cognitive Function in Elderly (운전재활프로그램이 노인의 인지기능에 미치는 효과)

  • Lee, Sungsook;Kim, Bora;Ha, Jaeyoung;Park, Jimin;Cho, Yeseul;Ha, Jinri;Hong, Useon;Kim, Sungwon
    • Journal of The Korean Society of Integrative Medicine
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    • v.2 no.4
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    • pp.91-100
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    • 2014
  • Purpose : The purpose of this experiment is to find out the effectiveness which exert influence on cognitive skills by using the Driver Rehabilitation program for senior citizens who are over 65 years old and live in Busan. Method : From July first, 2014 to August 28th, 2014, we researched the 60 elderly people who are over 65 and go to community relief center which is in Busan. - 30 are experimental group and the other is control group. In the experimental group, we used Nintendo wii's driving simulation program and RC Car driving program in the model road. For estimation, we used MVPT-3(Motor-Free Visual Perception Test-3), Trail Making Test - 1, Trail making Test - 2 and LOTCA(Loewenstein Occupational Therapy Cognitive Assessment). Result : Nintendo wii's driving simulation program and RC Car driving program in model road results efficient visual perception ability. This programs results effectively in visual perception ability and space perception ability. This programs results effectively in motor apraxia ability. This programs results effectively in control ability for visual perception. This programs results effectively in thinking operation. Conclusion : Nintendo Wii's driving simulation program and RC Car driving program in model road positively influence improving for visual perceptual ability and cognitive function of elderly people. Also it is considered as being more efficient for improving visual perceptual ability and cognitive function to implement basic rehabilitation training with driving rehabilitation program than basic training itself.

인지발달에 근거를 둔 수학학습 유형 탐색

  • 박성태
    • The Mathematical Education
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    • v.34 no.1
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    • pp.17-63
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    • 1995
  • The exploration of Mathematics-learningmodel on the basis of Cognitive development The purpose of this paper is to sequenctialize Mathematics-learning contents, and to explore teaching-learning model for mathematics, with on the basis of the theory of cognitive development and the period of condservation formation for children. The Specific topics are as follows: (1) Systemizing those theories of cognitive development which are related to Mathematics - learning for children. (2) Organizing a sequence of Mathematics - learning, on the basis of experimental research for the period of conservation formation for children. (3) Comparing the effects of 4 types of teaching - learning model, on the basis of inference activity and operational learning principle. $\circled1$ Induction-operation(IO) $\circled2$ Induction-explanation(IE) $\circled3$ Deduction-operation(DO) $\circled4$ Deduction-explanation(DE) The results of the subjects are as follows: (1) Cognitive development theory and Mathe-matics education. $\circled1$ Congnitive development can be achieved by constant space and Mathematics know-ledge is obtained by the interaction of experience and reason. $\circled2$ The stages of congnitive development for children form a hierarchical system, its function has a continuity and acts orderly. Therefore we need to apply cognitive development for children to teach mathematics systematically and orderly. (2) Sequence of mathematical concepts. $\circled1$ The learning effect of mathematical concepts occurs when this coincides with the period of conservation formation for children. $\circled2$ Mathematics Curriculum of Elementary Schools in Korea matches with the experimental research about the period of Piaget's conservation formation. (3) Exploration of a teaching-learning model for mathematics. $\circled1$ Mathematics learning is to be centered on learning by experience such as observation, operation, experiment and actual measurement. $\circled2$ Mathematical learning has better results in from inductional inference rather than deductional inference, and from operational inference rather than explanatory inference.

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Active Window to Reduce the Exterior Noise Flowed Through the Open Window (열린 창문을 통해 유입되는 소음을 저감하는 능동소음제어 창문)

  • Kwon, Byoung-Ho;Park, Young-Jin
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.21 no.9
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    • pp.820-827
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    • 2011
  • Recently, noise has been regarded as one of the most notorious and frequent environmental pollutions which can be often encountered not only in the living space but also in the industrial site. Studies on physiological and psychological effects of long-term noise exposure to human being have commanded the public interest on noise issues. Since environmental noises such as traffic noise and construction noise is mainly flowed through the open window, it is necessary to develop the active noise control system to reduce it inside the building. Although control speakers and microphones for the noise signal measurement in the control region are essential for the conventional active noise control methods, it is impossible to implement them in the control region in the building environment because the control region is the living quarter and they may hinder activities of the residents. Therefore, we proposed the active window system to reduce the exterior noise flowed through the open window with microphones installed outside the window and control speakers installed at the frame of the window. To confirm the performance of the proposed active window, we carried out the simulation and experiment using active window system with 8 control speakers. Simulation results showed the noticeable noise reduction effect inside the control region within the frequency range without the spatial aliasing. Experimental result showed that the total acoustic potential energy inside the room of the scale model is reduced to about 10dB within the interest of frequency range.