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Characterization of contribution of vehicle emissions to ambient NO2 using stable isotopes (안정동위원소를 이용한 이동오염원에 의한 대기 중 NO2의 거동특성 연구)

  • Park, Kwang-Su;Kim, Hyuk;Yu, Suk-Min;Noh, Seam;Park, Yu-Mi;Seok, Kwang-Seol;Kim, Min-Seob;Yoon, Suk Hee;Kim, Young-Hee
    • Analytical Science and Technology
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    • v.32 no.1
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    • pp.17-23
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    • 2019
  • Sources of NOx are both anthropogenic (e.g. fossil fuel combustion, vehicles, and other industrial processes) and natural (e.g. lightning, biogenic soil processes, and wildfires). The nitrogen stable isotope ratio of NOx has been proposed as an indicator for NOx source partitioning, which would help identify the contributions of various NOx sources. In this study, the ${\delta}^{15}N-NO_2$ values of vehicle emissions were measured in an urban region, to understand the sources and processes that influence the isotopic composition of NOx emissions. The Ogawa passive air sampler was used to determine the isotopic composition of $NO_2$(g). In urban tunnels, the observed $NO_2$ concentration and ${\delta}^{15}N-NO_2$ values averaged $3809{\pm}2656ppbv$ and $7.7{\pm}1.8$‰, respectively. The observed ${\delta}^{15}N-NO_2$ values are associated with slight regional variations in the vehicular $NO_2$ source. Both $NO_2$ concentration and ${\delta}^{15}N-NO_2$ values were significantly higher near the expressway ($965{\pm}125ppbv$ and $5.9{\pm}1.4$‰) than at 1.1 km from the expressway ($372{\pm}96ppbv$ and $-11.5{\pm}2.9$‰), indicating a high proportion of vehicle emissions. Ambient ${\delta}^{15}N-NO_2$ values were used in a binary mixing model to estimate the percentage of the ${\delta}^{15}N-NO_2$ value contributed by vehicular NOx emissions. The calculated percentage of the ${\delta}^{15}N-NO_2$ contribution by vehicles was significantly higher close to the highway, as observed for the $NO_2$ concentration and ${\delta}^{15}N-NO_2$.

The Real States of Affairs and Features of Fortune-Telling in Gwang-Ju (광주 점복(占卜)문화의 실상과 특징)

  • Pyo, In Ju
    • Korean Journal of Heritage: History & Science
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    • v.43 no.4
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    • pp.4-23
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    • 2010
  • Danggol, in other words the hereditary shaman, is a person who is performing the Gut(the Korean shamanistic ritual) as the job but fortuneteller simply tells someone's fortunes. Nowadays most of fortunetellers think their works are wholly managed the Gut as the holy jobs. But Generally this kinds of jobs, we think it is lower than ordinary people's level of education in the korea. Actually we can meet eleven fortunetellers who have a college diploma out of them, so we can know that their education's level is increasing gradually. On the other hand a house of fortunetellers is the place where can lead the way of our lives in the method of seeing one's past life or making predictions of someone's coming events etc. Gradually this place seems to be separated with a private home, so the most of them is managing as the monthly rent. Consequently this houses are heavily located at the Gyerim five-way crossing, the Yang-dong Dakjeonmeory street, Jungheung-dong local culture street area. Each fortunetellers have the different ways of fortune-telling because this methods are decided by their one's characters. So their fortune-telling time and its time required for a task is far different. The methods of telling it is very much different in accordance with the learning fortuneteller or spiritualistic fortuneteller. But the process of fortune-telling is common like as a preparatory stage, carrying a Jumsa(fortune-telling) stage and acting by a Jumsa stage. These steps are sequential but linked together. There are six special features of fortune-telling culture in Gwang-Ju. 1. The role of a fortuneteller and Bosal(spirit-descended shaman) runs at the same time. 2. The house of fortune-telling is doing Gutdang(ritual house)'s works. 3. Its location are heavily collectivized at the specific districts. 4. The learning fortuneteller are increasing gradually. 5. The youth are growing use in the fortune-telling house. 6. There are many person that are visiting this house because of individual problems not their family's problems.

An Optimization Method of Measuring Heart Position in Dynamic Myocardial Perfusion SPECT with a CZT-based camera (동적 심근관류 SPECT에서 심장의 위치 측정방법에 대한 고찰)

  • Seong, Ji Hye;Lee, Dong Hun;Kim, Eun Hye;Jung, Woo Young
    • The Korean Journal of Nuclear Medicine Technology
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    • v.23 no.1
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    • pp.75-79
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    • 2019
  • Purpose Cadmium-zinc-telluride (CZT) camera with semiconductor detector is capable of dynamic myocardial perfusion SPECT for coronary flow reserve (CFR). Image acquisition with the heart positioned within 2 cm in the center of the quality field of view (QFOV) is recommended because the CZT detector based on focused multi-pinhole collimators and is stationary gantry without rotation. The aim of this study was to investigate the optimal method for measuring position of the heart within the center of the QFOV when performing dynamic myocardial perfusion SPECT with the Discovery NM 530c camera. Materials and Methods From June to September 2018, 45 patients were subject to dynamic myocardial perfusion SPECT with D530c. For accurate heart positioning, the patient's heart was scanned with a mobile ultrasound and marked at the top of the probe where the mitral valve (MV) was visible in the parasternal long-axis view (PLAX). And, the marked point on the patient's body matched with the reference point indicated CZT detector in dynamic stress. The heart was positioned to be in the center of the QFOV in rest. The coordinates of dynamic stress and rest were compared statistically. Results The coordinates of the dynamic stress using mobile ultrasound and those taken of the rest were recorded for comparative analysis with regard to the position of the couch and analyzed. There were no statistically significant differences in the coordinates of Table in & out, Table up & down, and Detector in & out (P > 0.05). The difference in distance between the 2 groups was measured at $0.25{\pm}1.00$, $0.24{\pm}0.96$ and $0.25{\pm}0.82cm$ respectively, with no difference greater than 2 cm in all categories. Conclusion The position of the heart taken using mobile ultrasound did not differ significantly from that of the center of the QFOV. Therefore, The use of mobile ultrasound in dynamic stress will help to select the correct position of the heart, which will be effective in clinical diagnosis by minimizing the image quality improvement and the patient's exposure to radiation.

Utility Evaluation of Supportive Devices for Interventional Lower Extremity Angiography (인터벤션 하지 혈관조영검사를 위한 보조기구의 유용성 평가)

  • Kong, Chang gi;Song, Jong Nam;Jeong, Moon Taek;Han, Jae Bok
    • Journal of the Korean Society of Radiology
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    • v.13 no.4
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    • pp.613-621
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    • 2019
  • The purpose of this study is to evaluate the effectiveness of supportive devices which are for minimizing the patient's movement during lower extremity angiography and to verify image quality of phantom by analyzing of Mask image, DSA image and Roadmap image into SNR and CNR. As a result of comparing SNR with CNR of mask image obtained by DSA technique using the phantom alone and phantom placed on the supportive devices, there was no significant difference between about 0~0.06 for SNR and about 0~0.003 for CNR. The study showed about 0.11~0.35 for SNR and 0.016~0.031 for CNR of DSA imaging by DSA technique about only water phantom of the blood vessel model and the water phantom placed on the device. Analyzing SNR and CNR of Roadmap technique about water phantom on the auxiliary device (hardboard paper, pomax, polycarbonate, acrylic) and water phantom alone, there was no significant difference between 0.02~0.05 for SNR and 0.002~0.004 for CNR. In conclusion, there was no significant difference on image quality by using supportive devices made by hardboard paper, pomax, polycarbonate or acryl regardless of whether using supportive devices or not. Supportive devices to minimize of the patient's movement may reduce the total amount of contrast, exam-time, radiation exposure and eliminate risk factors during angiogram. Supportive devices made by hardboard paper can be applied easily during angiogram due to advantages of reasonable price and simple processing. It is considered that will be useful to consider cost efficiency and types of materials and their properties in accordance with purpose and method of the study when the operator makes and uses supportive devices.

Anomaly Detection for User Action with Generative Adversarial Networks (적대적 생성 모델을 활용한 사용자 행위 이상 탐지 방법)

  • Choi, Nam woong;Kim, Wooju
    • Journal of Intelligence and Information Systems
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    • v.25 no.3
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    • pp.43-62
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    • 2019
  • At one time, the anomaly detection sector dominated the method of determining whether there was an abnormality based on the statistics derived from specific data. This methodology was possible because the dimension of the data was simple in the past, so the classical statistical method could work effectively. However, as the characteristics of data have changed complexly in the era of big data, it has become more difficult to accurately analyze and predict the data that occurs throughout the industry in the conventional way. Therefore, SVM and Decision Tree based supervised learning algorithms were used. However, there is peculiarity that supervised learning based model can only accurately predict the test data, when the number of classes is equal to the number of normal classes and most of the data generated in the industry has unbalanced data class. Therefore, the predicted results are not always valid when supervised learning model is applied. In order to overcome these drawbacks, many studies now use the unsupervised learning-based model that is not influenced by class distribution, such as autoencoder or generative adversarial networks. In this paper, we propose a method to detect anomalies using generative adversarial networks. AnoGAN, introduced in the study of Thomas et al (2017), is a classification model that performs abnormal detection of medical images. It was composed of a Convolution Neural Net and was used in the field of detection. On the other hand, sequencing data abnormality detection using generative adversarial network is a lack of research papers compared to image data. Of course, in Li et al (2018), a study by Li et al (LSTM), a type of recurrent neural network, has proposed a model to classify the abnormities of numerical sequence data, but it has not been used for categorical sequence data, as well as feature matching method applied by salans et al.(2016). So it suggests that there are a number of studies to be tried on in the ideal classification of sequence data through a generative adversarial Network. In order to learn the sequence data, the structure of the generative adversarial networks is composed of LSTM, and the 2 stacked-LSTM of the generator is composed of 32-dim hidden unit layers and 64-dim hidden unit layers. The LSTM of the discriminator consists of 64-dim hidden unit layer were used. In the process of deriving abnormal scores from existing paper of Anomaly Detection for Sequence data, entropy values of probability of actual data are used in the process of deriving abnormal scores. but in this paper, as mentioned earlier, abnormal scores have been derived by using feature matching techniques. In addition, the process of optimizing latent variables was designed with LSTM to improve model performance. The modified form of generative adversarial model was more accurate in all experiments than the autoencoder in terms of precision and was approximately 7% higher in accuracy. In terms of Robustness, Generative adversarial networks also performed better than autoencoder. Because generative adversarial networks can learn data distribution from real categorical sequence data, Unaffected by a single normal data. But autoencoder is not. Result of Robustness test showed that he accuracy of the autocoder was 92%, the accuracy of the hostile neural network was 96%, and in terms of sensitivity, the autocoder was 40% and the hostile neural network was 51%. In this paper, experiments have also been conducted to show how much performance changes due to differences in the optimization structure of potential variables. As a result, the level of 1% was improved in terms of sensitivity. These results suggest that it presented a new perspective on optimizing latent variable that were relatively insignificant.

Development of a deep neural network model to estimate solar radiation using temperature and precipitation (온도와 강수를 이용하여 일별 일사량을 추정하기 위한 심층 신경망 모델 개발)

  • Kang, DaeGyoon;Hyun, Shinwoo;Kim, Kwang Soo
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.21 no.2
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    • pp.85-96
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    • 2019
  • Solar radiation is an important variable for estimation of energy balance and water cycle in natural and agricultural ecosystems. A deep neural network (DNN) model has been developed in order to estimate the daily global solar radiation. Temperature and precipitation, which would have wider availability from weather stations than other variables such as sunshine duration, were used as inputs to the DNN model. Five-fold cross-validation was applied to train and test the DNN models. Meteorological data at 15 weather stations were collected for a long term period, e.g., > 30 years in Korea. The DNN model obtained from the cross-validation had relatively small value of RMSE ($3.75MJ\;m^{-2}\;d^{-1}$) for estimates of the daily solar radiation at the weather station in Suwon. The DNN model explained about 68% of variation in observed solar radiation at the Suwon weather station. It was found that the measurements of solar radiation in 1985 and 1998 were considerably low for a small period of time compared with sunshine duration. This suggested that assessment of the quality for the observation data for solar radiation would be needed in further studies. When data for those years were excluded from the data analysis, the DNN model had slightly greater degree of agreement statistics. For example, the values of $R^2$ and RMSE were 0.72 and $3.55MJ\;m^{-2}\;d^{-1}$, respectively. Our results indicate that a DNN would be useful for the development a solar radiation estimation model using temperature and precipitation, which are usually available for downscaled scenario data for future climate conditions. Thus, such a DNN model would be useful for the impact assessment of climate change on crop production where solar radiation is used as a required input variable to a crop model.

The Character of Bogamni group and trends in the surrounding area seen through the stone chamber (석실로 본 나주 복암리 세력과 주변 지역의 동향)

  • Kim, Nak jung
    • Korean Journal of Heritage: History & Science
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    • v.49 no.1
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    • pp.44-67
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    • 2016
  • This article studied the character of Bogamri group and trends in the surrounding area through recently excavated stone chambers. The first type of stone chamber constructed at Bogamni cemetry was Northen Kyushu style stone chamber tomb with corridor. However, According to recent survey Wa style vertical stone lined tomb had constructed earlier than these stone chamber along the southwest cost. It is likely that the background of these Wa style stone tomb was the beginning of formal diplomatic relations between Baekje and Wa. At first, grave goods as well as burial had been Wa style, but gradually local burial element and mortuary practices added. And large tomb had beginning to appear. The representative tombs are Yeongam Okyari Jangdong tomb and Naju Gaheugni Shinhueng tomb. They were built in the middle of the fifth century. It is most likely that the location was selected with regard to the use or securing of inland waterway. But the next step, Yeongsangang river style stone chamber with corridor had constructed at Jeongchon tomb. That tomb is very close to Bogamni tombs and structure and grave goods are very similar also. So these two groups were considered to be the same community. Hereby, It is believed that the inland waterway using power had been turned over to Bogamni group. Bogamni group had constantly constructed stone chamber until seventh century. This represent that Bogamni group had thrived as a leading force in the Yeongsangang river basin. After under the direct control of Baekje, Bogamni group had continued the close relationship with Wa. For this reason, Bogamni group had influenced southwest cost as well as Yeongsangang river basin. It can be estimated by the Bogamni style stone chamber founded at islands of Shinan.

Study on Korea Social Perceptions on the Forest Fires of Newspaper Analysis (신문사설 분석을 통한 산불에 대한 사회적 인식연구)

  • Kim, Bomi;Park, Joowon
    • Journal of Korean Society of Forest Science
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    • v.108 no.1
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    • pp.88-96
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    • 2019
  • The purpose of this study is to understand when forest fire as a natural phenomenon becomes constructed as social issues in Korea; how the forest fire-related discourses in the editorials reflecting the social perceptions have been changed regarding the principal subject and the measures of the forest fire management; and whether the social perception on the forest fire affects the forest fire policy of the state. From the analysis of a total of 44 editorials related to forest fires from 1988 to 2017. By the using, in the forest fire-related editorials the social perceptions on forest fires are forest fire editorials categories, main keywords, contents of social perception on 'the main subject responsible for forest fire management,' 'forest fire prevention measures,' categorization, frequency analysis and context analysis of words used. It is found that in the first-period forest fire management measures were recognized as a part of the overall forest management. In the second period, the approaches of ecological management emerged on the part of forest fire management. As forest fires were managed as a type of social disaster during the third period, such perceptions were gradually reinforced that the state should protect the people from the forest fire. In the 3rd, 4th, and 5th National Forest Plan, the forest fire management policy of each period was focused in enlightening the general public, protecting forest resources ecosystems, and preventing loss of lives, respectively. As a result of the analysis of social perceptions and comparing them to the forest fire policies through the analysis of editorials on forest fires, it is found that the social perception on the forest fire and forest fire management plan has changed having interconnections.

Comparison and Review of GBEF% on the Anterior and Right Lateral Images of Nuclear Hepatobiliary Scan (핵의학 간담도 스캔 시, 전면상과 우측 측면상에서의 담낭박출률에 대한 비교 및 고찰)

  • Lee, Eun-Byeol;Kim, Jae-Il;Do, Yong-Ho;Llm, Jung-Jin;Cho, Sung-Wook;Noh, Gyeong-Woon
    • The Korean Journal of Nuclear Medicine Technology
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    • v.22 no.2
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    • pp.92-96
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    • 2018
  • Purpose In case of nuclear medical hepatobiliary scan, To quantitatively evaluate contractility of a gallbladder, gallbladder ejection fraction (GBEF%) is calculated from anterior images using fatty meal. However, when a gallbladder and other organs overlap on an anterior image, the gallbladder ejection fraction is not accurately evaluated. In order to reduce this error, the objective of our study was to figure out whether there is a significant difference in GBEF% calculated from the anterior and right lateral images. Materials and Methods After intravenous injection of 99mTc-Mebrofenin 370 MBq to randomly 50 patients who visited our hospital, we started to examine nuclear hepatobiliary scan. Using skylight(Philips, United States), we acquired anterior and right lateral image at 10 minutes, 20 minutes, 30 minutes, 60 minutes, 90minutes after injection. Using images at 60 and 90 minutes, gallbladder ejection fraction (GBEF%) was calculated from the anterior and right lateral images using JETstream workspace. For drawing more accurate ROI, CT images were referenced and 4 radiologists calculated the GBEF% in the same image and calculated the average value. We assessed whether there was a significant difference in GBEF% calculated from the anterior and right lateral images using SPSS program(Statistical Package for the Social Science, SPSS Ver.18 Inc. USA). Results About randomly 50 patients, the average value of the GBEF% calculated from the anterior image was 63.212 and the average value of the GBEF% calculated from the right lateral image was 62.666. GBEF% decreased 0.433% on the right lateral image compared with anterior image. Result of paired sample t-test, p value is over 0.05. So, there was no significant difference in GBEF% calculated from the anterior and right lateral images. Conclusion In the case that a gallbladder and other organs are not separated on an anteior image, Right lateral image would be better to acquire more accurate GBEF% than using anterior image.

A Study on the Thermal Conductivity Measurement for Planting Mats of Landscaping (조경용 식생매트의 열전도율 측정에 관한 연구)

  • Cha, Uk Jin;Yang, Geon Seok
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.6
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    • pp.85-96
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    • 2018
  • Developed nations have implemented various policies to reduce greenhouse gases since the 1997 Kyoto Protocol in order to minimize the effects of global warming. Korea should also reduce energy consumption in the industrial sector, and the transportation and building sectors in order to achieve its greenhouse gas reduction target of 37 percent compared to the Business As Usual levels. The government implements various laws and regulations for reducing energy consumption. To reduce energy consumption in the building sector, in particular, the Energy Conservation Design Standards are enforced according to the 'Enforcement Support for Green Building Construction'. The amount of electricity used to maintain room temperature at $28^{\circ}C$ in these buildings have a 30% reduction (measured on the walls and rooftop) in power usage compared to buildings not required to meet these standards. Although the effect of these energy savings on landscaping is proven, this demonstration is not effective for energy saving since it is not a suitable method for the 'Energy Saving Design Standards of Buildings'. For landscaping to be effective as far as a component of energy reduction, the perfusion rate of the building should be calculated based on the thermal conductivity of the component materials for the energy saving designs with respect to the basis of Article 14 of the Green Building Act. Therefore, the purpose of this study is to ensure that the planting-based mats currently being widely used in the landscape industry can have insulating performance suitable for the 'Energy Saving Design Standards' of Buildings according to the 'Enable Green Building Construction Methods'.