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Evaluation for applicability of river depth measurement method depending on vegetation effect using drone-based spatial-temporal hyperspectral image (드론기반 시공간 초분광영상을 활용한 식생유무에 따른 하천 수심산정 기법 적용성 검토)

  • Gwon, Yeonghwa;Kim, Dongsu;You, Hojun
    • Journal of Korea Water Resources Association
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    • v.56 no.4
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    • pp.235-243
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    • 2023
  • Due to the revision of the River Act and the enactment of the Act on the Investigation, Planning, and Management of Water Resources, a regular bed change survey has become mandatory and a system is being prepared such that local governments can manage water resources in a planned manner. Since the topography of a bed cannot be measured directly, it is indirectly measured via contact-type depth measurements such as level survey or using an echo sounder, which features a low spatial resolution and does not allow continuous surveying owing to constraints in data acquisition. Therefore, a depth measurement method using remote sensing-LiDAR or hyperspectral imaging-has recently been developed, which allows a wider area survey than the contact-type method as it acquires hyperspectral images from a lightweight hyperspectral sensor mounted on a frequently operating drone and by applying the optimal bandwidth ratio search algorithm to estimate the depth. In the existing hyperspectral remote sensing technique, specific physical quantities are analyzed after matching the hyperspectral image acquired by the drone's path to the image of a surface unit. Previous studies focus primarily on the application of this technology to measure the bathymetry of sandy rivers, whereas bed materials are rarely evaluated. In this study, the existing hyperspectral image-based water depth estimation technique is applied to rivers with vegetation, whereas spatio-temporal hyperspectral imaging and cross-sectional hyperspectral imaging are performed for two cases in the same area before and after vegetation is removed. The result shows that the water depth estimation in the absence of vegetation is more accurate, and in the presence of vegetation, the water depth is estimated by recognizing the height of vegetation as the bottom. In addition, highly accurate water depth estimation is achieved not only in conventional cross-sectional hyperspectral imaging, but also in spatio-temporal hyperspectral imaging. As such, the possibility of monitoring bed fluctuations (water depth fluctuation) using spatio-temporal hyperspectral imaging is confirmed.

A Study on the Radiographic Diagnosis of Caroli's Disease (카롤리병의 방사선학적 진단에 대한 고찰)

  • Yeo-jin Hong;Min-a Kim;Soo-bin Kim;Jin-joo Song;Kyoung-hoon Jang;Min-cheol Jeon;Man-Seok Han
    • Journal of the Korean Society of Radiology
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    • v.17 no.3
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    • pp.385-392
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    • 2023
  • Caroli's disease is a fibrocystic liver disease. Autosomal recessive disorder is characterized by congenital multiple dilatation of the bile duct. Computerized tomography, magnetic resonance imaging, cholangiography and ultrasound are among the methods for diagnosing caroli disease. Computerized tomography is essential for detecting and distinguishing fibroplastic liver disease and is useful for determining intrahepatic bile duct dilatation. However, awareness of the possible side effects of using contrast mediums is necessary. A typical method of magnetic resonance cholangiography is used for magnetic resonance imaging. A non-invasive examination can reduce the pain of the patient, and the anatomical structure of the bile pancreatic duct and the presence or absence of lesions can be easily and quickly observed. Biliary contrast is an effective diagnostic method that can directly visualize various cystic dilatations throughout the enlarged bile duct. However, since this procedure is also an invasive procedure, it is recommended not for diagnosis but for treatment purposes. Ultrasonography can confirm similar findings to computerized tomography. The hepatic artery root is difficult to prove with conventional grayscale ultrasound. However, it is of clinical value in that it can not only describe dilated bile ducts with vascular roots in the tube but also easily identify color Doppler signals in the tube. With the development of video diagnostics, early diagnosis has become possible through computerized tomography, magnetic resonance imaging, cholangiography, and ultrasound. In order to further contribute to the development of video diagnostics so that long-term prognosis can be improved after treatment through early diagnosis, we examined what aspects of each test's caroli disease appear.

Usefulness of Deep Learning Image Reconstruction in Pediatric Chest CT (소아 흉부 CT 검사 시 딥러닝 영상 재구성의 유용성)

  • Do-Hun Kim;Hyo-Yeong Lee
    • Journal of the Korean Society of Radiology
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    • v.17 no.3
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    • pp.297-303
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    • 2023
  • Pediatric Computed Tomography (CT) examinations can often result in exam failures or the need for frequent retests due to the difficulty of cooperation from young patients. Deep Learning Image Reconstruction (DLIR) methods offer the potential to obtain diagnostically valuable images while reducing the retest rate in CT examinations of pediatric patients with high radiation sensitivity. In this study, we investigated the possibility of applying DLIR to reduce artifacts caused by respiration or motion and obtain clinically useful images in pediatric chest CT examinations. Retrospective analysis was conducted on chest CT examination data of 43 children under the age of 7 from P Hospital in Gyeongsangnam-do. The images reconstructed using Filtered Back Projection (FBP), Adaptive Statistical Iterative Reconstruction (ASIR-50), and the deep learning algorithm TrueFidelity-Middle (TF-M) were compared. Regions of interest (ROI) were drawn on the right ascending aorta (AA) and back muscle (BM) in contrast-enhanced chest images, and noise (standard deviation, SD) was measured using Hounsfield units (HU) in each image. Statistical analysis was performed using SPSS (ver. 22.0), analyzing the mean values of the three measurements with one-way analysis of variance (ANOVA). The results showed that the SD values for AA were FBP=25.65±3.75, ASIR-50=19.08±3.93, and TF-M=17.05±4.45 (F=66.72, p=0.00), while the SD values for BM were FBP=26.64±3.81, ASIR-50=19.19±3.37, and TF-M=19.87±4.25 (F=49.54, p=0.00). Post-hoc tests revealed significant differences among the three groups. DLIR using TF-M demonstrated significantly lower noise values compared to conventional reconstruction methods. Therefore, the application of the deep learning algorithm TrueFidelity-Middle (TF-M) is expected to be clinically valuable in pediatric chest CT examinations by reducing the degradation of image quality caused by respiration or motion.

A Comprehensive Review of Geological CO2 Sequestration in Basalt Formations (현무암 CO2 지중저장 해외 연구 사례 조사 및 타당성 분석)

  • Hyunjeong Jeon;Hyung Chul Shin;Tae Kwon Yun;Weon Shik Han;Jaehoon Jeong;Jaehwii Gwag
    • Economic and Environmental Geology
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    • v.56 no.3
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    • pp.311-330
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    • 2023
  • Development of Carbon Capture and Storage (CCS) technique is becoming increasingly important as a method to mitigate the strengthening effects of global warming, generated from the unprecedented increase in released anthropogenic CO2. In the recent years, the characteristics of basaltic rocks (i.e., large volume, high reactivity and surplus of cation components) have been recognized to be potentially favorable in facilitation of CCS; based on this, research on utilization of basaltic formations for underground CO2 storage is currently ongoing in various fields. This study investigated the feasibility of underground storage of CO2 in basalt, based on the examination of the CO2 storage mechanisms in subsurface, assessment of basalt characteristics, and review of the global research on basaltic CO2 storage. The global research examined were classified into experimental/modeling/field demonstration, based on the methods utilized. Experimental conditions used in research demonstrated temperatures ranging from 20 to 250 ℃, pressure ranging from 0.1 to 30 MPa, and the rock-fluid reaction time ranging from several hours to four years. Modeling research on basalt involved construction of models similar to the potential storage sites, with examination of changes in fluid dynamics and geochemical factors before and after CO2-fluid injection. The investigation demonstrated that basalt has large potential for CO2 storage, along with capacity for rapid mineralization reactions; these factors lessens the environmental constraints (i.e., temperature, pressure, and geological structures) generally required for CO2 storage. The success of major field demonstration projects, the CarbFix project and the Wallula project, indicate that basalt is promising geological formation to facilitate CCS. However, usage of basalt as storage formation requires additional conditions which must be carefully considered - mineralization mechanism can vary significantly depending on factors such as the basalt composition and injection zone properties: for instance, precipitation of carbonate and silicate minerals can reduce the injectivity into the formation. In addition, there is a risk of polluting the subsurface environment due to the combination of pressure increase and induced rock-CO2-fluid reactions upon injection. As dissolution of CO2 into fluids is required prior to injection, monitoring techniques different from conventional methods are needed. Hence, in order to facilitate efficient and stable underground storage of CO2 in basalt, it is necessary to select a suitable storage formation, accumulate various database of the field, and conduct systematic research utilizing experiments/modeling/field studies to develop comprehensive understanding of the potential storage site.

Molecular Breeding of Tobacco Plants Resistant to TMV and PVY (분자생물학적 TMV 및 PVY 저항성 연초 육종)

  • E.K. Pank;Kim, Y.H.;Kim, S.S.;Park, S.W.;Lee, C.H.;K.H.Paik
    • Proceedings of the Korean Society of Tobacco Science Conference
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    • 1997.10a
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    • pp.134-152
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    • 1997
  • Plant viruses of tobacco including tobacco mosaic virus (TMV) and potato virus Y (PVY) cause severe economic losses in leaf-tobacco production. Cultural practices do not provide sufficient control against the viruses. Use of valuable resistant cultivars is most recommendable for the control of the viruses. However, conventional breeding programs are not always proper for the development of virus-resistant plants mostly owing to the frequent lack of genetic sources and introduction of their unwanted properties. Therefore, we tried to develop virus-resistant tobacco plants by transforming commercial tobacco cultivars, NC 82 and Burley 21, with coat protein (CP) or replicase (Nlb) genes of TMV and PVY necrosis strain (PVY-VN) with or without untranslated region (UTR) and with or without mutation. Each cDNA was cloned and inserted in plant expression vectors with 1 or 2 CaMV 35S promotors, and introduced into tobacco leaf tissues by Agrobacterium tumefaciens LBA 4404. Plants were regenerated in kanamycin-containing MS media. Regenerated plants were tested for resistance to TMV and PVY In these studies, we could obtain a TMV-resistant transgenic line transformed with TMV CP and 6 genetic lines with PVY-VN cDNAs out of 8 CP and replicase genes. In this presentation, resistance rates, verification of gene introduction in resistant plants, stability of resistance through generations, characteristics of viral multiplication and translocation in resistant plants, and resistance responses relative to inoculum potential and to various PVY strains will be shown. Yield and quality of leaf tobacco of a promising resistant tobacco line will be presented.

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Growth and Yield in Early Seasonal Cultivation for Rice Double Cropping in Southern Korean Paddy Field (벼 2기작 재배를 위한 조기재배 환경에서 벼 생육 및 수량변화)

  • Ku, Bon-Il;Choi, Min-Kyu;Kang, Shin-Ku;Park, Tae-Seon;Kim, Young-Doo;Park, Hong-Kyu;Ko, Jae-Kwon;Lee, Byun-woo
    • Journal of the Korean Society of International Agriculture
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    • v.23 no.5
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    • pp.520-530
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    • 2011
  • This study was carried out to evaluate the possibility of rice double cropping in Korea by assessing the growth and yield performance of rice cultivars transplanted at the extremely-early date. When the transplanted rice seedling was exposed to low temperature below 0℃, the survival rate decreased drastically. However, short exposure to below 0℃ one or two times did not damage transplanted rice seedling so severely. Thus, the earliest transplanting in spring would be possible when minimum temperature rises above 0℃. Compared with the conventional seedling nursery tray (CSNT), seedling rearing with the potted nursery tray was more effective for increasing leaf age and seedling dry weight during nursery period. In the first rice cropping, rice cultivation with seedlings reared in PSNT showed shorter growth duration and cumulative temperature from transplanting to heading than that with seedlings reared in CSNT. The earliest heading date on July 4 in Jinbuolbyeo was earlier by two to three days than that of Dunaebyeo. If rice has not exposed to cold damage, the earliest heading date of Jinbujolbyeo can advance to June 30 or July 1. In this case, rice harvest would be possible on August 5, enabling the rice transplanting of the second rice cropping before August 10. At transplanting time with low temperature damage rice yield were less than 400 kg/10a while rice yield exceeded 400 kg/10a at transplanting time without low temperature damage.

A Critical Study of the Legend on the Chinese Ancient Dynasty's Succession before Yao-Shun Era : Focusing on the Rongchengshi in the Shanghai Bowuguan zang Zhanguo Chuzhushu(II) (上海博物館蔵戦国楚竹書 《容成氏》 の古帝王帝位継承説話研究)

  • 李承律
    • Journal of the Daesoon Academy of Sciences
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    • v.17
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    • pp.197-225
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    • 2004
  • The respective history of the Chinese Ancient Dynasties from the era of the ancient Emperors to the revolutionary era of Yin-Zhou殷周 was described in the Rongchengshi容成氏, one of the texts in Shanghai Bowuguan zang Zhanguo Chuzhushu(II)上海博物館藏戰國楚竹書(二) discovered in 1994 at an antique market in Hong Kong. Drawn from the historical explanations expressed in it, the anonymous author's own views on history could be observed as largely being composed of 'resignation'禪讓, 'usurpation'簒奪, and 'banishment/smite'放伐. Following the advent of the recently excavated bamboo slips of Rongchengshi, a careful reconsideration is urgently needed to the established interpretation on the origin of the ritual of resignation in the relevant academic circles. Because it shows us that the ritual of resignation as a way of the succession, judging from my analysis, was already realized by Nine Emperors('Rongchengshi', Zunlushi尊盧氏, Hexushi赫胥氏, Gaoxinshi高辛氏, Cangjieshi倉頡氏, Xuanyuanshi軒轅氏, Shennongshi神農氏, 渾沌氏, and Baoxishi包羲氏 and maybe the more) before the era of 'Yao-Shun'堯舜. Accordingly, the aforementioned fact, which has never been elaborated in the previous texts including the first Chinese historiography Shiji史記, is the only peculiar feature to the Rongchengshi itself. Thus, a simple but empirically important question could be raised here: Was this way of description an exceptional case, even as unaccepted in Warring States Period at that time? If then, the Rongchengshi could not but help being evaluated merely as a buried historical texts, without any influence on the ancient Chinese, along with its author. The Chu bamboo slips Tangyu zhi dao唐虞之道 from Guodian Chujian郭店 excavated in 1993, however, has a very similar content to the Rongchengshi in relevance to the historical existence of the ritual of resignation. From the sentence, expressed in Tangyu zhi dao, that "the sudden rise of 'Six Emperors'六帝 was due to the practice of resignation like the period of Yao-Shun", it could be easily presumed that the 'Six Emperors' was closely connected to the 'Nine Emperors' and maybe the more at that time. Comparing with the related extant literary texts and the excavated materials in a vigorous way, in this paper, I explore four significant questions from a more critical stand to the conventional studies. First of all, I explicate the distinctiveness of the Rongchengshi as an academically very precious materials. Secondly, and closely related to the above, I evaluate its status or significance in the history of the Chinese ancient thoughts. And thirdly, I make an endeavor to trace back to the date of its transcription. Finally, and the most crucially, I attempt to show what Schools it was originated from and what connections it had with the Schools in the acient China. In sum, some concluding remarks, having somewhat insightful and significant implications for the further studies in these issues, could be drawn from my exploration. Viewing from the historical perspective of thoughts, at first, the legend of Ancient Dynasty's Succession before Yao-Shun Era in the Rongchengshi had some interactions directly and closely with Zhangzi莊子, Muzi墨子, Guanzi管子, Xunzi荀子 and Tangyu zhi dao. Also in doing search for the unification in a transitional epoch from the late to the end of the Warring States period, the political stand of Shi士 and Ke客 was reflected in it as well as in the Tangyu zhi dao because they actively wanted to suggest the most appropriate model of the Emperor or the idealistic succession process and political realms.

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An Experimental Study on Fine Dust Emissions near Special Modified Asphalt Pavement and Conventional Asphalt Pavement (특수개질 및 일반 아스팔트 포장체 도로변의 미세먼지 발생에 대한 실험적 연구)

  • Tae-Woo Kang;Hyeok-Jung Kim
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.11 no.3
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    • pp.282-288
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    • 2023
  • In this study, we analyzed the amount of roadside fine dust generated from newly constructed specially modified asphalt pavement and general asphalt pavement from existing roads. We collected the 1,000 g (100 g/day) of dust samples from the roadside of the express bus terminal and commercial facility area in Chungcheongnam-do's C site at three-day intervals during the summer of 2022 and 2023. The collected samples were separated from fine dust according to size in the 75-150 ㎛ range and, were separated only from Tire and Road Wear Particles through density separation. No.1-3 are general asphalt pavement section as an existing road. Fine dust and Tire and Road Wear Particles in No.1-3 were 24.27 g, 24.36 g, 0.53 g, and 0.53 g, respectively, and the quantitative results for 2022 and 2023 were similar. On the other hand, No.4-6 are newly constructed specially modified asphalt pavement section. Fine dust decreased by 14.8 % and tire and road wear particles decreased by 29.6 % in 2023 compared to 2022 in No.4-6. In addition, according to the results of thermogravimetric analysis, Tire and road wear particles in No.1-3 are tire and road components at 30 % and 70 %, respectively. And Tire and road wear particles in No.4-6 are tire and road components at 35 % and 65 % in 2023, respectively. From these results, it was confirmed that the newly constructed specially modified asphalt pavement can be effective in reducing roadside fine dust and Tire and Road Wear Particles. However, there may be some shortcomings in conclusive research results due to limited space and sample collection period. In the future, we plan to conduct various case studies.

Estimation of Rice Canopy Height Using Terrestrial Laser Scanner (레이저 스캐너를 이용한 벼 군락 초장 추정)

  • Dongwon Kwon;Wan-Gyu Sang;Sungyul Chang;Woo-jin Im;Hyeok-jin Bak;Ji-hyeon Lee;Jung-Il Cho
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.25 no.4
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    • pp.387-397
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    • 2023
  • Plant height is a growth parameter that provides visible insights into the plant's growth status and has a high correlation with yield, so it is widely used in crop breeding and cultivation research. Investigation of the growth characteristics of crops such as plant height has generally been conducted directly by humans using a ruler, but with the recent development of sensing and image analysis technology, research is being attempted to digitally convert growth measurement technology to efficiently investigate crop growth. In this study, the canopy height of rice grown at various nitrogen fertilization levels was measured using a laser scanner capable of precise measurement over a wide range, and a comparative analysis was performed with the actual plant height. As a result of comparing the point cloud data collected with a laser scanner and the actual plant height, it was confirmed that the estimated plant height measured based on the average height of the top 1% points showed the highest correlation with the actual plant height (R2 = 0.93, RMSE = 2.73). Based on this, a linear regression equation was derived and used to convert the canopy height measured with a laser scanner to the actual plant height. The rice growth curve drawn by combining the actual and estimated plant height collected by various nitrogen fertilization conditions and growth period shows that the laser scanner-based canopy height measurement technology can be effectively utilized for assessing the plant height and growth of rice. In the future, 3D images derived from laser scanners are expected to be applicable to crop biomass estimation, plant shape analysis, etc., and can be used as a technology for digital conversion of conventional crop growth assessment methods.

Absorption Characteristics of Water-Lean Solvent Composed of 3-(Methylamino)propylamine and N-Methyl-2-Pyrrolidone for CO2 Capture (3-메틸아미노프로필아민과 N-메틸-2-피롤리돈을 포함한 저수계 흡수제의 CO2 포집 특성)

  • Shuai Wang;Jeong Hyeon Hong;Jong Kyun You;Yeon Ki Hong
    • Korean Chemical Engineering Research
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    • v.61 no.4
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    • pp.555-560
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    • 2023
  • Conventional aqueous amine-based CO2 capture has a problem in that a large amount of renewable energy is required for CO2 stripping and solvent regeneration in its industrial applications. This work proposes a water-lean absorbent that can reduce regeneration energy by lowering the water content in the absorbent with high absorption capacity for CO2. To this purpose, this water-lean solvent introduced NMP (N-methyl-2-pyrrolidone), which has a higher physical solubility in CO2 and a low specific heat capacity comparing to water, along with 3-methylaminopropylamine (MAPA), a diamine, into the absorbent. The circulating absorption capacity and absorption rate for CO2 of this water-lean solvent were measured using a packed tower. When NMP was added to the absorbent, the absorption rate was improved. In the case of the absorbent containing 2.5M MAPA was used, the maximum circulating absorption capacity was obtained when 10 wt% of NMP was included in absorbent. The overall mass transfer coefficient increased as the concentration of NMP increased. However, at loading values higher than 0.5, the increment in mass transfer coefficient decreased as the concentration of NMP increased. When the lean loading value is low, the mass transfer resistance due to viscosity of the absorbent is low, so the overall mass transfer coefficient increases with the addition of NMP. However, as the lean loading value increases, the viscosity of the absorbent increases, and the diffusivity of CO2 and MAPA decreases, resulting in sharply decreasing of the overall mass transfer coefficient.