• Title/Summary/Keyword: low-order control

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Efficient Multi-spot Monitoring System Using PTZ Camera and Wireless Sensor Network (PTZ 카메라와 무선 센서 네트워크를 이용한 효율적인 다중 지역 절전형 모니터링 시스템)

  • Seo, Dong-kyu;Son, Cheol-su;Yang, Su-yeong;Cho, Byung-lok;Kim, Won-jung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.581-584
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    • 2009
  • Recently, the cameras which used for observation are installed in children protection area and local crime prevention area in order to protect life and property and by its work being recognized and are installed more. Normal cameras have cost problem to observe multiple area and detail, because they can observe only one place. PTZ camera can observe multiple area by moving focus by schedule or remote control, but it can't automatically move the focus of it to the place where event occurred, because it can't recognize the place. In this study, we can monitor multiple area effectively, by installing a wireless sensor node equipped with temperature, lighting, gas and human detection sensor to each area, to monitor many place low-price and actively and to move the focus of PTZ camera to preset position, and send recorded video to the user, when the various sensor data received from wireless sensors in observation area are to be determined abnormal by analyzing. In addition, at night we can record a scene using infrared, but to reduce power consumption of lighting system which are installed to improve resolution, it supplies power to the lighting system when event occurred. So we were able to implement low power green monitoring system.

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Oral Health Behavior and Dietary Habits of Dental Hygiene Students and Caries-Causing Factor Test (치위생과 학생의 구강건강행위 및 식이습관과 우식발생요인검사)

  • Kim, Ki-Eun;Hwang, Ji-Min
    • The Journal of the Convergence on Culture Technology
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    • v.4 no.4
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    • pp.135-144
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    • 2018
  • The purpose of this study is to investigate the relationship between oral health behavior and dietary habits and caries occurrence test and to provide basic data necessary for prevention of dental caries. The average salivary salivary fraction was 8.35ml and the non - amorphous salivary fraction was 2.41ml. The salivary buffering ability was 9.29 and the mean glucose retention time was 15.81 minutes. In the Streptococcus mutans colony count test, low risk group <105 was 80.5% and low risk group <105 was 84.4% in Lactobacillus colony count test. Correlation between caries test scores showed a positive correlation between salivary ratio and non - salivary ratio, saliva buffering ability, non - salivary fraction and glucose retention time, and Lactobacillus. Factors affecting the irritant saliva fraction were alcohol as a factor affecting the ratio of nuts, pork, and non - irritant saliva. In order to prevent dental caries, proper dietary control education should be combined with dental caries activity test and oral health education for proper eating habits.

Developement of Small 360° Oral Scanner Embedded Board for Image Processing (소형 360° 구강 스캐너 영상처리용 임베디드 보드 개발)

  • Ko, Tae-Young;Lee, Sun-Gu;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.22 no.4
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    • pp.1214-1217
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    • 2018
  • In this paper, we propose the development of a Small $360^{\circ}$ Oral Scanner embedded board. The proposed small $360^{\circ}$ oral scanner embedded board consists of image level and transfer method changing part FPGA part, memory part and FIFO to USB transfer part. The image level and transmission mode change unit divides the MIPI format oral image received through the small $360^{\circ}$ oral cavity image sensor and the image sensor into low power signal mode and high speed signal mode and distributes them to the port and transfers the level shift to the FPGA unit. The FPGA unit performs functions such as $360^{\circ}$ image distortion correction, image correction, image processing, and image compression. In the FIFO to USB transfer section, the RAW data transferred through the FIFO in the FPGA is transferred to the PC using USB 3.0, USB 3.1, etc. using the transceiver chip. In order to evaluate the efficiency of the proposed small $360^{\circ}$ oral scanner embedded board, it has been tested by an authorized testing institute. As a result, the frame rate per second is over 60 fps and the data transfer rate is 4.99 Gb/second

The effect of policy on Korean personal assistance service for persons with disabilities of labor market participation (장애인활동지원서비스제도의 노동시장 참여에 대한 정책효과)

  • Kim, Song Sook;Kim, Yoo-Min;Na, Ga-Yeon;Baek, Seung-Hee;Lee, Kun-Chul
    • Journal of the Korea Convergence Society
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    • v.12 no.4
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    • pp.267-274
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    • 2021
  • This study used data from the 6rd and 12th year of the Korean Welfare Panel to evaluate the effects of the Personal Assistance Service(PAS) system on the labor market of PAS users' participation. For the purpose of this study, 64 program groups using the Korean PAS and 344 control groups not using the Korean PAS were selected using Caliper matching among the propensity score matching. A chi-square test was used for the difference in characteristics between groups, and a simple difference-in-differences (DID) model and a double-difference multiple regression analysis of DID were performed to estimate the effect of thepolicy before and after the Korean PAS. As a result of the study, it was found that statistically, PAS had no significant effect on the labor market. This is due to the low number of system users, resulting in low post-hoc power, incomplete matching and limited availability of PAS Assistants for Disabled People. Therefore, In order to demonstrate the effectiveness of the Personal Assistance Service(PAS) system, specialized services and systems that meet the needs of the disabled and household members should be implemented.

Validity of Linear Combination Approach based on Net Damping Analysis of Cable-Damper System (케이블-댐퍼 시스템의 전체감쇠비 해석을 통한 선형조합 접근법의 유효성)

  • Kim, Hyeon Kyeom;Hwang, Jae Woong;Lee, Myeong Jae
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.5A
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    • pp.467-475
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    • 2009
  • Existing studies have suggested Universal Curve only for supplemental damping by damper. Therefore net damping has been determined by means of arithmetic summation between intrinsic, aero-damping of cable and supplemental damping of damper. However linear combination approach by means of the arithmetic summation is not enough theoretical background. So validity of this approach should be verified in order to design adequate cable-damper system by engineers. This study establishes governing differential equation which can consider intrinsic, aero-damping and supplemental damping as well. And also analysis method is solved by combination of muller method and successive iteration method. Consequently, this study succeeds in verification for validity of linear combination approach. As a result of this study, linear combination approach is limitedly effective in case of low stiffness and optimum damping coefficient of damper, short distance from support to damper, lower vibration mode, low aero-damping, and normal windy environment. Whereas this study will be effective in case of opposite conditions, and existing studies or linear combination approach occur to further error. Meaning of this study presents exact solution for net damping of cable-damper system, and verifies linear combination approach by means of the analysis method. In the future, if monitoring of optimum damping coefficient of a damper against aero-damping is feasible on time, algorithm of this study will be available for control of cable and semi-active damper system such as magneto-rheological damper.

Batch Scale Storage of Sprouting Foods by Irradiation Combined with Natural Low Temperature - III. Storage of Onions - (방사선조사(放射線照射)와 자연저온(自然低溫)에 의한 발아식품(發芽食品)의 Batch Scale 저장(貯藏)에 관한 연구(硏究) - 제3보(第三報) 양파의 저장(貯藏) -)

  • Cho, Han-Ok;Kwon, Joong-Ho;Byun, Myung-Woo;Yang, Ho-Sook
    • Applied Biological Chemistry
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    • v.26 no.2
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    • pp.82-89
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    • 1983
  • In order to develop a commercial storage method of onions by irradiation combined with natural low temperature, two local varieties of onions, precocious species and late ripening, were stored at natural low temperature storage room ($450{\times}650{\times}250cmH.$; year-round temperature change, $2{\sim}17^{\circ}C$; R.H., $80{\sim}85%$) on batch scale following irradiation with optimum dose level. Precocious and late varieties were all sprouted after five to seven months storage, whereas $10{\sim}15$ Krad irradiated precocious variety was $2{\sim}4%$ sprouted after nine months storage, but sprouting was completly inhibited at the same dose for late variety. The extent of loss due to rot attack after ten months storage were $23{\sim}49%$ in both control and irradiated group of precocious variety but those of late variety were only $4{\sim}10%$. The weight loss of irradiated precocious variety after ten months storage was $13{\sim}16$, while that of late variety was $5.3{\sim}5.9%$ after nine months storage. The moisture content, during whole storage period, of two varieties were $90{\sim}93$ with negligible changes. The total sugar content differed little with varieties and doses immediatly after irradiation, but decreased by the elapse of storage period. 33.6% of its content was decreased in control and 12.5% in irradiated group but $20{\sim}26$ decreased in both control and irradiated group of late variety after nine months storage. No appreciable change was observed immediately after irradiation irrespective of variety and dose, but decreased slightly with storage. Ascorbic acid content of precocious variety was increased slightly with dose immediately after irradiation, but those of late variety decreased slightly. Ascorbic acid content were generally decreased during whole storage period. An economical preservation method of onions appliable to late variety, would be to irradiate onion bulbs at dost range of $10{\sim}15$ Krad followed by storage at natural low temperature storage room.

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Study of Oil Palm Biomass Resources (Part 5) - Torrefaction of Pellets Made from Oil Palm Biomass - (오일팜 바이오매스의 자원화 연구 V - 오일팜 바이오매스 펠릿의 반탄화 연구 -)

  • Lee, Ji-Young;Kim, Chul-Hwan;Sung, Yong Joo;Nam, Hye-Gyeong;Park, Hyeong-Hun;Kwon, Sol;Park, Dong-Hun;Joo, Su-Yeon;Yim, Hyun-Tek;Lee, Min-Seok;Kim, Se-Bin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.48 no.2
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    • pp.34-45
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    • 2016
  • Global warming and climate change have been caused by combustion of fossil fuels. The greenhouse gases contributed to the rise of temperature between $0.6^{\circ}C$ and $0.9^{\circ}C$ over the past century. Presently, fossil fuels account for about 88% of the commercial energy sources used. In developing countries, fossil fuels are a very attractive energy source because they are available and relatively inexpensive. The environmental problems with fossil fuels have been aggravating stress from already existing factors including acid deposition, urban air pollution, and climate change. In order to control greenhouse gas emissions, particularly CO2, fossil fuels must be replaced by eco-friendly fuels such as biomass. The use of renewable energy sources is becoming increasingly necessary. The biomass resources are the most common form of renewable energy. The conversion of biomass into energy can be achieved in a number of ways. The most common form of converted biomass is pellet fuels as biofuels made from compressed organic matter or biomass. Pellets from lignocellulosic biomass has compared to conventional fuels with a relatively low bulk and energy density and a low degree of homogeneity. Thermal pretreatment technology like torrefaction is applied to improve fuel efficiency of lignocellulosic biomass, i.e., less moisture and oxygen in the product, preferrable grinding properties, storage properties, etc.. During torrefacton, lignocelluosic biomass such as palm kernell shell (PKS) and empty fruit bunch (EFB) was roasted under an oxygen-depleted enviroment at temperature between 200 and $300^{\circ}C$. Low degree of thermal treatment led to the removal of moisture and low molecular volatile matters with low O/C and H/C elemental ratios. The mechanical characteristics of torrefied biomass have also been altered to a brittle and partly hydrophobic materials. Unfortunately, it was much harder to form pellets from torrefied PKS and EFB due to thermal degradation of lignin as a natural binder during torrefaction compared to non-torrefied ones. For easy pelletization of biomass with torrefaction, pellets from PKS and EFB were manufactured before torrefaction, and thereafter they were torrefied at different temperature. Even after torrefaction of pellets from PKS and EFB, their appearance was well preserved with better fuel efficiency than non-torrefied ones. The physical properties of the torrefied pellets largely depended on the torrefaction condition such as reaction time and reaction temperature. Temperature over $250^{\circ}C$ during torrefaction gave a significant impact on the fuel properties of the pellets. In particular, torrefied EFB pellets displayed much faster development of the fuel properties than did torrefied PKS pellets. During torrefaction, extensive carbonization with the increase of fixed carbons, the behavior of thermal degradation of torrefied biomass became significantly different according to the increase of torrefaction temperature. In conclusion, pelletization of PKS and EFB before torrefaction made it much easier to proceed with torrefaction of pellets from PKS and EFB, leading to excellent eco-friendly fuels.

Variations in Ammonium Removal Rate with Tidal State in the Macrotidal Han River Estuary: Potential Role of Nitrification (한강기수역에서의 암모늄 제거율 변화 및 질산화의 잠재적 역할)

  • Hyun, Jung-Ho;Chung, Kyung-Ho;Park, Yong-Chul;Choi, Joong-Ki
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.1
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    • pp.33-39
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    • 1999
  • In order to understand the importance of tidal action and $NH_4{^+}$ -nitrification in the removal of dissolved oxygen (DO) and $NH_4{^+}$, concentrations of DO, $NH_4{^+}$, $NO_2{^-}$ and $NO_3{^-}$ were measured with time for water samples collected at different tidal state in the eutrophic macrotidal Han River estuary. Field measurements indicated that most environmental parameters, except for the water temperature and DO concentration, were tightly controlled by the eutrophic freshwater runoff and large-scale tidal action. Dark incubation of the water sample at $25^{\circ}C$ showed that the removal rates of DO and $NH_4{^+}$ in high tide sample were 2.76 ${\mu}M\;O_2\;d^{-1}$ and 1.76 ${\mu}M\;N\;d^{-1}$ respectively, and increased to 5.66 ${\mu}M\;O_2\;d^{-1}$ and 3.36 ${\mu}M\;N\;d^{-1}$ respectively, in low tide sample. These changes indicated that microbial degradation and uptake of organic matter and inorganic nutrients were more active during low tide. $NH_4{^+}$-nitrification responsible for total DO removal in low tide (23.81%) and $NH_4{^+}$ turnover rates due to $NH_4{^+}$-nitrification in low tide (0.18 $d^{-1}$) were approximately 3.7 times and 3 times, respectively, higher than those in high tide. These results indicated that $NH_4{^+}$ -nitrifying bacteria introduced into the Han River estuary during low tide played a significant role in the removal of DO and $NH_4{^+}$. The decreasing removal rates in DO and $NH_4{^+}$ with the increasing tidal level seemed to be associated with the salinity impact on the halophobic freshwater $NH_4{^+}$-nitrifying bacteria. The results implied that anthropogenic $NH_4{^+}$ sources should be treated prior to the freshwater runoff into the estuary for the effective control of $NH_4{^+}$ in the Han River estuary. These results also suggest that parallel ecological studies on the chemoautotrophic nitrifying bacteria are essential for the elucidation of nitrogen cycles in the eutrophic Han River estuary.

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Perspective of breaking stagnation of soybean yield under monsoon climate

  • Shiraiwa, Tatsuhiko
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.8-9
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    • 2017
  • Soybean yield has been low and unstable in Japan and other areas in East Asia, despite long history of cultivation. This is contrasting with consistent increase of yield in North and South America. This presentation tries to describe perspective of breaking stagnation of soybean yield in East Asia, considering the factors of the different yields between regions. Large amount of rainfall with occasional dry-spell in the summer is a nature of monsoon climate and as frequently stated excess water is the factor of low and unstable soybean yield. For example, there exists a great deal of field-to-field variation in yield of 'Tanbaguro' soybean, which is reputed for high market value and thus cultivated intensively and this results in low average yield. According to our field survey, a major portion of yield variation occurs in early growth period. Soybean production on drained paddy fields is also vulnerable to drought stress after flowering. An analysis at the above study site demonstrated a substantial field-to-field variation of canopy transpiration activity in the mid-summer, but the variation of pod-set was not as large as that of early growth. As frequently mentioned by the contest winners of good practice farming, avoidance of excess water problem in the early growth period is of greatest importance. A series of technological development took place in Japan in crop management for stable crop establishment and growth, that includes seed-bed preparation with ridge and/or chisel ploughing, adjustment of seed moisture content, seed treatment with mancozeb+metalaxyl and the water table control system, FOEAS. A unique success is seen in the tidal swamp area in South Sumatra with the Saturated Soil Culture (SSC), which is for managing acidity problem of pyrite soils. In 2016, an average yield of $2.4tha^{-1}$ was recorded for a 450 ha area with SSC (Ghulamahdi 2017, personal communication). This is a sort of raised bed culture and thus the moisture condition is kept markedly stable during growth period. For genetic control, too, many attempts are on-going for better emergence and plant growth after emergence under excess water. There seems to exist two aspects of excess water resistance, one related to phytophthora resistance and the other with better growth under excess water. The improvement for the latter is particularly challenging and genomic approach is expected to be effectively utilized. The crop model simulation would estimate/evaluate the impact of environmental and genetic factors. But comprehensive crop models for soybean are mainly for cultivations on upland fields and crop response to excess water is not fully accounted for. A soybean model for production on drained paddy fields under monsoon climate is demanded to coordinate technological development under changing climate. We recently recognized that the yield potential of recent US cultivars is greater than that of Japanese cultivars and this also may be responsible for different yield trends. Cultivar comparisons proved that higher yields are associated with greater biomass production specifically during early seed filling, in which high and well sustained activity of leaf gas exchange is related. In fact, the leaf stomatal conductance is considered to have been improved during last a couple of decades in the USA through selections for high yield in several crop species. It is suspected that priority to product quality of soybean as food crop, especially large seed size in Japan, did not allow efficient improvement of productivity. We also recently found a substantial variation of yielding performance under an environment of Indonesia among divergent cultivars from tropical and temperate regions through in a part biomass productivity. Gas exchange activity again seems to be involved. Unlike in North America where transpiration adjustment is considered necessary to avoid terminal drought, under the monsoon climate with wet summer plants with higher activity of gas exchange than current level might be advantageous. In order to explore higher or better-adjusted canopy function, the methodological development is demanded for canopy-level evaluation of transpiration activity. The stagnation of soybean yield would be broken through controlling variable water environment and breeding efforts to improve the quality-oriented cultivars for stable and high yield.

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Identification of LED Lights for the Attraction of Bemisia Tabaci and Effect of Host Plant in the Initial Periods (담배가루이 유인용 LED 선발과 기주식물이 초기 유인력에 미치는 영향)

  • Kwon, D.H.;Kwon, M.J.;Yang, D.Y.;Ahn, Y.K.;Hong, K.H.;Park, M.R.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.22 no.2
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    • pp.123-133
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    • 2020
  • Four LEDs (blue, green, red, and white light) were tested to identify the most attractive wave length to utilize as the forecasting tools for the B. tabaci in glass houses. Attractiveness was evaluated by the total number of the B. tabaci attached to a yellow sticky trap. In the condition of no host plant supplement, the attraction efficacy was ordered from high to low as blue light (107.3±2.5), white light (83.0±12.1), red light (58±21.8), and green light (39.7±8.1). In the supplement of the host plant, the attraction was observed in the order of blue light (52±17.4), red light (38.7±5.8), green light (12.7±1.5), and white light (11.7±5.0). In both experimental conditions, blue light showed the highest attraction. In terms of the host plant effect to LED attraction, it varied following as white light (85.9%), green light (68.1%), blue light (51.6%), and red light (33.3%). This result suggests that red light is the least affected by the host plant. In the evaluation of the relative control efficacy, it was determined following as red light (66.7%), blue light (48.5%), green light (31.9%) and white light (14.1%) (F3,8 = 14.7, P = 0.001). Taken together, blue light had a very high initial attraction, and red light was revealed low attraction effect by the supplement of the host plant. In field demonstration experiments, a high attractive efficacy was not observed due to low-temperature conditions, but similar higher attractive efficacy was observed in blue and red lights compared to the control. The commercialization of LEDs using red and blue in the future is expected to provide important information regarding B. tabaci population density forecast in glass house.