• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.123-132
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• 2016

The importance of energy saving technology for managing greenhouse was recently highlighted. For practical use of energy in greenhouse, it is necessary to simulate energy flow precisely and estimate heating/cooling loads of greenhouse. So the main purpose of this study was to develope and to validate greenhouse energy model and to estimate annual/maximum energy loads using Building Energy Simulation (BES). Field experiments were carried out in a multi-span plastic-film greenhouse in Jeju Island ($33.2^{\circ}N$, $126.3^{\circ}E$) for 2 months. To develop energy model of the greenhouse, a set of sensors was used to measure the greenhouse microclimate such as air temperature, humidity, leaf temperature, solar radiation, carbon dioxide concentration and so on. Moreover, characteristic length of plant leaf, leaf area index and diffuse non-interceptance were utilized to calculate sensible and latent heat exchange of plant. The internal temperature of greenhouse was compared to validate the greenhouse energy model. Developed model provided a good estimation for the internal temperature throughout the experiments period (coefficients of determination > 0.85, index of agreement > 0.92). After the model validation, we used last 10 years weather data to calculate energy loads of greenhouse according to growth stage of greenhouse crop. The tendency of heating/cooling loads change was depends on external weather condition and optimal temperature for growing crops at each stage. In addition, maximum heating/cooling loads of reference greenhouse were estimated to 644,014 and $756,456kJ{\cdot}hr^{-1}$, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.5
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• pp.451-457
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• 2006

The purpose of this study is to measure fundamental data required for the prediction of rice quality and to develop regression models to predict protein, amylose, moisture and fatty acid contents, and Toyo taste meter value (TTMV) of brown and polished rice from hulled rice NIR spectra. NIR spectra of hulled rice measured in transmittance mode (850-1050 nm) and in reflectance mode (400-2500 nm) were used to predicted chemical compositions of brown rice and polished rice. For most chemicals, the transmittance spectra could provide better calibration results than the reflectance ones. Beside the Toyo taste meter value (TTMV), the hulled rice spectra could predict chemical contents with the determination coefficients higher than 0.8. Spectra of hulled rice measured in transmittance mode could be used for the prediction of chemical compositions in brown rice and polished rice precisely. However, taste value of polished rice was a constituent that was hardly to be predicted.

• Journal of Biosystems Engineering
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• v.17 no.3
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• pp.247-259
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• 1992

This study intended to measure the desorption and adsorption EMC of four years old Peeled ginseng, Unpeeled ginseng and Taegeuk ginseng under various conditions$20^{\circ}C$, $30^{\circ}C$, $40^{\circ}C$, $50^{\circ}C$) and five levels of relative humidity from 31% to 88%) by the static method. Four widely used EMC models were selected and evaluated. Also the empirical model was evaluated. The results are summarized as follows ; 1) EMC difference between ginseng size was not found but found between ginseng species. EMC difference between Peeled ginseng and Unpeeled ginseng was not found. EMC of Peeled ginseng and Unpeeled ginseng was higher than that of Taegeuk ginseng. 2) The hysteresis, which is difference between desorption and adsorption EMC, was found. Desorption EMC was higher than adsorption EMC. The hysteresis at the same temperature decreased as relative humidity increase. The difference of hysteresis between Peeled ginseng and Unpeeled ginseng was not large and the hysteresis of Taegeuk ginseng was smaller than those of other species. 3) Among the selected models, Henderson model was the best to predict the adsorption EMC of White ginseng(Peeled and Unpeeled ginseng), and Oswin model was the best to predict the desorption EMC of White ginseng and the desorption and adsorption EMC of Taegeuk ginseng. The models are as follows ; (a) White ginseng(Peeled and Unpeeled ginseng) ${\circ}$ Desorption EMC(Oswin model) : $$M=(0.1272-0.0007420T){\cdot}[RH/(1-RH)]^{(0.4164+0.001368T)}$$ ${\circ}$ Adsorption(Henderson model) : $$1-RH={\exp}[-0.0003480T_k\;{M_o}^{0.9231}]$$ (b) Taegeuk ginseng ${\circ}$ Desorption EMC(Oswin model) : $$M=(0.1051-0.0008439T)[RH/(1-RH)]^{(0.4553+0.003425T)}$$ ${\circ}$ Adsorption EMC(Oswin model) : $$M=(0.08247-0.0007559T){\cdot}[RH/(1-RH)]^{(0.5760+0.005540T)}$$ 4) The developed empirical models could predict the desorption and adsorption EMC for White and Taegeuk ginseng more precisely than selected models. The empirical models are as follows ; (a) White ginseng(Peeled and Unpeeled ginseng) ${\circ}$ Desorption EMC : $$M=0.124-0.000647T-0.216RH+0.373RH^2$$ ${\circ}$ Adsorption EMC : $$M=0.0879-0.000663T-0.197RH+0.399RH^2$$. (b) Taegeuk ginseng ${\circ}$ Desorption EMC : $$M=0.159-0.000728T-0.429RH+0.565RH^2$$ ${\circ}$ Adsorption EMC : $$M=0.123-0.000662T-0.384RH+0.555RH^2$$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.826-833
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• 2017

It is important to localize trains precisely for the purpose of controlling them and there have been many studies designed to accomplish this without the need for wayside systems. Since trains run on fixed railway lines, it is possible to search in one direction to localize them. Moreover, it is also possible to know the shape of the line in advance. In the case of high speed trains, their speed and, therefore, their Doppler frequency is relatively high and the railway line is either linear or circular with a large radius. In this study, we utilize these features and propose a train localization method using the Doppler frequency of the signals transmitted from two points (base stations). We derive localization equations for a linear line, circular line, and mixed line (linear plus circular) respectively. Though Doppler radars are usually used to measure speed, the proposed method obtains the location information and the speed successively using the ratio of the doppler frequencies of two signals without knowing the location information or the speed. Computer simulations are performed to show the variation of the estimation error according to the train's location and the measurement error level. The conditions required to obtain the target error level and the increase in the estimation error according to the measurement error are compared between the proposed and conventional methods. The results show the superior performance and robustness of the proposed method.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.5
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• pp.77-87
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• 2018

Traffic Density is the most important of the three primary macroscopic traffic stream parameters, because it is most directly related to traffic demand(Traffic Engineering, 2004). It is defined as the number of existing vehicles within a given distance at a certain time. However, due to weather, road conditions, and cost issues, collecting density directly on the field is difficult. This makes studies of density less actively than those of traffic volume or velocity. For these reasons, there is insufficient attempts on divers collecting methods or researches on the accuracy of measured values. In this paper, we used the 'Density Measuring System' based on the synthesise technology of several camera images as a method to measure density. The collected density value by the 'Density Mesuring System' is selected as the true value based on the density define, and this value was compared with the density calculated by the traditional measurement methods. As a result of the comparison, the density value using the fundamental equation method is the closest to the true value as RMSE shows 1.8 to 2.5. In addition, we investigated some issues that can be overlooked easily such as the collecting interval to be considered on collecting density directly by calculating the moment density and the average density. Despite the actual traffic situation of the experiment site is LOS B, it is difficult to judge the real traffic situation because the moment density values per second are observed max 16.0 (veh/km) to min 2.0 (veh/km). However, the average density measured for 15 minutes at 30-second intervals was 8.3-7.9 (veh/km) and it indicates precisely LOS B.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.1
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• pp.42-52
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• 2017

DASH (Dynamic Adaptive Streaming over HTTP) is an adaptive streaming technique that enables transmission of multimedia content when clients request the multimedia contents to server. In this system, to ensure the best quality of the content to satisfy users, it is necessary to precisely measure the residual bandwidth. However, the measured residual bandwidth by the DASH, which is not considering the transmission features of TCP, varies by the size of previous media segment, which makes it hard to ensure QoE to users. In this paper, we excluded the TCP Slow start range from measurement of residual bandwidth and suggested the new DASH bandwidth measuring method to decrease the error. Then, we realized the method in DASH system based on open source, and compared the existing measuring method. The new method showed that the accuracy of result has increased by 20%. Also, it could improve the QoE of users in terms of service quality and number of changes of segment quality.

• Journal of the Korean Institute of Educational Facilities
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• v.1 no.1
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• pp.33-40
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• 1994

This study was taken to increase efficiency in reviewing documents of school facilities from the network of ERIV(Educational Resources and Information Center, USA). Outline of the ERIC network, and the structure, role, function of the ERIC thesaurus are introduced. A thesaurus have developed for information retrieval purpose provides the filing labels which permit information to be stored by one person and retrieved by another. As an information system grows, its thesaurus is systematically built and refined to the point where it represents, in a very special sense, the vocabulary of subject field. The Thesaurus of ERIC Descriptors represents such a vocabulary for the field education. An understanding of its origins, its function and its limitations, is just as important to the teacher, the student of education or the educational researcher as it is for the indexer or custodian of the information pool it represents. If the Thesaurus is understood and used in an appropriate way, it can give all educators not only insight into the ERIC system but also an increased awareness of the language of their field. A great many terms are necessary to describe the many aspects of education, and the task of relating them in even an approximately consistent way is an enormous one. The undertaking should be managed by people who not only know what they are talking about but who also should be able to predict what people in their field are lilely to be talking about in the near future. It should also enlist people who are willing to pay term to another within the system. To engage a large number of these two kinds of people over a long period of time is very likely to cost a great deal of money. There is very little proprietary value in producing such a list of terms, for it can very easily be copied, adapted, updated, etc. Thus, because of its high cost and low proprietary value, it becomes a task likely to be funded only by a government. A government has many ways of spending its money. However, after the decision has been made to spend money to produce an authority list, one must decide how this authority is to be delegated. The history of the development of the ERIC Thesaurus is the history of how this authority was delegated. Scientific research has thrived on efforts to define terms as precisely as possible. It is difficult to say with certainty, however, that solutions to social problems have thrived on a simple diet of scientific research. Contemporary crises demand new and imaginative ways of conceiving problems and talking about them. If this Thesaurus or any other scheme for normalizing or controlling language inhibits in the slightest measure the creative use of language, it is against it use. Only if the principles and details of the Thesaurus are misunderstood can it be used as a constraint on language in a negative sense. Students of education of every kind should see the The-saurus as an opportunity to become increasingly self-conscious about their language and thus about their assumptions and their approaches to educational problems.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.2
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• pp.183-191
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• 2007

Through out the world dental caries seems to be decreased as it is difficult to make an accurate diagnosis for dental caries. The traditional diagnostic method which is probing and x-ray taking has many limitations to diagnose the early caries, so there were recommendations for the needs of new equipments such as laser fluorescence(LF), digital imaging fiber-optic trans-illumination(DIFOTI), and quantitative light fluorescence (QLF) which were developed from various study results. Also confocal laser scanning microscopy(CLSM) and ultrasonics are used for research progression. This study is to evaluate whether it is possible to monitor accurately for remineralization amount of enamel surface early caries using DIFOTI or LF After inducing artificial caries to bovine teeth to 10 participants remineralization was enhanced by 0 ppm and 500 ppm fluoride mouth rinse solution for 3 weeks. Then they were cross sectioned and analyzed using gold standard of the lesion depth measured by CLSM. The following results were obtained: 1. The measured percentage of light intensity(luminosity ratio) by DIFOTI increased with remineralization period, and showed significant reverse correlation with lesion depth measured by CLSM (p<0.01). 2. The measurement of laser fluorescence increased with remineralization period, and showed significant correlation with lesion depth measured by CLSM (p<0.01). 3. To the result for CLSM, 500 ppm fluoride mouth rinse group showed rapid rate for decreased tendency of lesion depth than 0 ppm fluoride mouth rinse group. In conclusion DIFOTI system was used to measure accurately for the remineralization amount of early surface caries, it is a very useful equipment to detect precisely the changes for early enamel caries remineralization during treatments.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.2 s.302
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• pp.113-120
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• 2005

3D reconstruction of a scene structure from un-calibrated image sequences has been long one of the central problems in computer vision. For 3D reconstruction in Euclidean space, projective reconstruction, which is classified into the merging method and the factorization, is needed as a preceding step. By calculating all camera projection matrices and structures at the same time, the factorization method suffers less from dia and error accumulation than the merging. However, the factorization is hard to analyze precisely long sequences because it is based on the assumption that all correspondences must remain in all views from the first frame to the last. This paper presents a new projective reconstruction method for recovery of 3D structure over long sequences. We break a full sequence into sub-sequences based on a quantitative measure considering the number of matching points between frames, the homography error, and the distribution of matching points on the frame. All of the projective reconstructions of sub-sequences are registered into the same coordinate frame for a complete description of the scene. no experimental results showed that the proposed method can recover more precise 3D structure than the merging method.

• Journal of Acupuncture Research
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• v.33 no.4
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• pp.15-31
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• 2016

Objectives : The aim of this study is to review the instruments used to assess patient condition and the effects of Korean medical treatment for patients injured in traffic accidents in clinical studies in the Korean medical field published in South Korea. Methods : A literature study was performed, and clinical studies on patients injured in traffic accidents visiting Korean medical clinics or hospitals were examined. Data about chief complaints, tools used to assess either patients' condition or the effectiveness of Korean medical treatment, and time point of assessment were extracted. The studies were classified according to symptom. The use-frequency and the parent category of the assessment tools were also analyzed. Results : 78 studies were selected and classified into 5 categories based on the chief complaints, neck pain, lower back pain, headache, psychological symptoms and unspecified symptoms. Various scales were used to report the patient's pain severity, and functional or psychological status resulting from traffic accidents. Pain index, in particular VAS, was most frequently used and a few mechanical instruments and Korean medicinal assessment tools were mentioned. Conclusion : Most instruments used in Korean medicine clinical studies on patients injured in traffic accidents are self-reported tools. To assess both the patient's condition precisely and the effectiveness of Korean medical treatment on patients injured in traffic accidents, more appropriate and unified tools should be designed that consider pain, functional disability, psychological status and objective assessments measured by devices together.