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Evaluation of Rapeseed Seedling Quality According to Varieties and Seedling Ages for Spring Cultivation Transplanting (유채 봄 재배 기계이식을 위한 품종별 육묘 일수에 따른 묘소질 평가)

  • An, Da-Hee;Cha, Young-Lok;Kim, Kwang-Soo;Shin, Woon-Chul;Lee, Ji-Eun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.66 no.3
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    • pp.256-264
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    • 2021
  • Rapeseed (Brassica napus L.) is generally sown in late autumn and harvested in early summer in Korea, however, spring cultivation has also been attempted in some areas because frequent climate changes induce reducing productivity. Therefore, there is a need for a transplanting technology that is relatively easy to control of cropping season according to changes in cultivation conditions. In this study, to find out the optimal characteristics of seedlings for machine transplanting of spring cultivation, seedling morphological characteristics were investigated according to the seedling age of three varieties for 2020 and 2021. The hypocotyl length was less than 2 cm in both years and the 40-day-old seedling was the shortest among all seedling ages. The number and size of leaf were increased with longer seedling age in both years. To evaluate seedling quality, total seedling length, seedling weight, and impact resistance were measured before transplanting. Total seedling length was the longest in 40-day-old seedlings and the shortest in 25-day-old seedlings in both years. In the case of seedling weight, no significant differences were observed depending on the seedling age and the impact resistance increased with increasing seedling age. Finally, 'Jungmo7001', 'Naehan', and 'Tamla' showed a high transplanting rate in seedlings grown for more than 30 days, 35 days, and 40 days, respectively, in the field using a general transplanter. These results suggest that the proper seedling age for transplanting is limited depending on the rapeseed varieties. The suitable seedling cultivation method can be selected for different cultivation environments.

A study on the characteristics of Goryeo dynasty cargo tag mokkans In comparison with mokkans of the Song and Yuan dynasty (고려시대 화물표 목간의 특징에 대한 고찰 - 중국 송·원대(宋·元代) 목간과의 비교를 중심으로 -)

  • LEE, Yeonjae
    • Korean Journal of Heritage: History & Science
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    • v.54 no.4
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    • pp.60-77
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    • 2021
  • From 2007 to 2011, four Goryeo Dynasty vessels, namely the Taean treasure ship, Taean Mado Shipwreck No.1, No.2, No.3 were discovered in Taean area, Chungcheongnam-do province. From the shipwrecks, 175 pieces of mokkan (wooden tablet) were excavated. These mokkans are the only case of Goryeo Dynasty and represent the unique usage of mokkan as cargo tags, after the paper replaced the wooden tablets as writing materials. The Taean mokkans provide details, such as the year, recipient, port of origin, types of the cargo, quantity and unit, the name of the responsible person for shipment. Thus, they enable us to speculate about the characteristics of the cargo. Furthermore, through studying the writing style, form, material and manufacturing method, researchers can extract which form and characteristics were favored at that time. The Taean mokkans have no preset style for writing. Therefore, they can be written selectively and freely. And since the mokkan were attached to cargos, mokkans with furrows on upper side were favored, and efficiency and simplification of the manufacturing process were priorities in making mokkans. The Taean mokkans can be compared to those from the Shinan ship and the Quanzhou ship because those are of the same era and use. On the writing styles and information, Chinese mokkans are focused on the cargo owners, while The Taean mokkan includes more detailed information, such as the recipients. In forms, Chinese mokkans have maximum thickness of 1.0 centimeter and have pointed edges in lower parts, while mokkans from Taean do not have fixed thickness or edges. Furthermore, Chinese mokkans and Korean mokkans have different styles from manufacturing methods and material selections. These differences between Chinese and Goryeo mokkan are related to the differences between littoral-transport Goryeo ships and ocean-transport Chinese ships, such as shipping distances, types of cargo, shipping systems, packing methods, and transport operators. At the moment, because there are only small amount of data and materials of Chinese mokkan, comparative studies regarding Goryeo and Chinese mokkan can only be fragmentary. However, this article can be a base from which to expand the scope of Goryeo mokkan studies.

A Study on the Characteristics of the Atmospheric Environment in Suwon Based on GIS Data and Measured Meteorological Data and Fine Particle Concentrations (GIS 자료와 지상측정 기상·미세먼지 자료에 기반한 수원시 지역의 도시대기환경 특성 연구)

  • Wang, Jang-Woon;Han, Sang-Cheol;Mun, Da-Som;Yang, Minjune;Choi, Seok-Hwan;Kang, Eunha;Kim, Jae-Jin
    • Korean Journal of Remote Sensing
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    • v.37 no.6_2
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    • pp.1849-1858
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    • 2021
  • We analyzed the monthly and annual trends of the meteorological factors(wind speeds and directions and air temperatures) measured at an automated synoptic observation system (ASOS) and fine particle (PM10 and PM2.5) concentrations measured at the air quality monitoring systems(AQMSs) in Suwon. In addition, we investigated how the fine particle concentrations were related to the meteorological factors as well as urban morphological parameters (fractions of building volume and road area). We calculated the total volume of buildings and the total area of the roads in the area of 2 km × 2 km centered at each AQMS using the geographic information system and environmental geographic information system. The analysis of the meteorological factors showed that the dominant wind directions at the ASOS were westerly and northwesterly and that the average wind speed was strong in Spring. The measured fine particle concentrations were low in Summer and early Autumn (July to September) and high in Spring and Winter. In 2020, the annual mean fine particle concentration was lowest at most AQMSs. The fine particle concentrations were negatively and weakly correlated with the measured wind speeds and air temperatures (the correlation between PM2.5 concentrations and air temperatures was relatively strong). In Suwon city, at least for 6 AQMSs except for the RAQMS 131116 and AQMS 131118, the PM10 concentrations were affected mainly by the transport from outside rather than primary emission from mobile sources or wind speed decrease caused by buildings and, in the case of PM2.5, vise versa.

Effect of Reversible Air-circulation Fans on Air Uniformity in a Cultivation Facility for Oyster Mushroom (느타리재배사 정역 제어 대류팬이 공기 균일도에 미치는 영향)

  • Yum, Sung Hyun;Kim, Si Hwan
    • Journal of Bio-Environment Control
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    • v.30 no.4
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    • pp.383-392
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    • 2021
  • It has been known that oyster mushrooms cultivated in facilities with thermal insulation have been strongly affected by inner environments. Forced air-circulation fans exert much direct influence on disturbing air inside the facility so the matter is of particular interest. This study is carried out to investigate the measured levels of air uniformity in a cultivation facility for oyster mushroom in the various cases that reversibly controlled air-circulation fans which drove the flow in the upward and reverse direction by turn and unidirectional fans by which the wind blew upwards only were operated from July 1 to 10. The actual survey for the selection of ongoing operation cases presented that farmers, even though there were some discrepancies, have made use of fans in a way that it paused for 5-30min after running for 5-15min by turn. The level of air uniformity in the case of adopting reversible fans revealed a slight difference of 1.4-1.8℃ (Temp.) and 7.8-8.7% (R.H.) under the condition of not using a cooler during the investigation period. By contrast, unidirectional fans showed a noticeable difference of 3.2-3.7℃ and 14.0-15.4%, which meant that air uniformity driven by reversible fans much more increased compared to that for unidirectional fans. Among the twenty operational applications considered for reversible fans, the circumstance that the wind blew upwards for 10-15min and ceased for 5-10min and blew again in the reverse direction for 10-15min in succession gave minor improvements at the level of air uniformity, but at present there was somewhat difficult to make decision on which cases were optimally best. It seems necessary that the effects of reversible fans on air uniformity as well as qualities of oyster mushrooms have to be appraised in the cultivation period and the flow visualization needs to be done to ascertain the performance of air mixture.

Comparison of Reflectance and Vegetation Index Changes by Type of UAV-Mounted Multi-Spectral Sensors (무인비행체 탑재 다중분광 센서별 반사율 및 식생지수 변화 비교)

  • Lee, Kyung-do;Ahn, Ho-yong;Ryu, Jae-hyun;So, Kyu-ho;Na, Sang-il
    • Korean Journal of Remote Sensing
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    • v.37 no.5_1
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    • pp.947-958
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    • 2021
  • This study was conducted to provide basic data for crop monitoring by comparing and analyzing changes in reflectance and vegetation index by sensor of multi-spectral sensors mounted on unmanned aerial vehicles. For four types of unmanned aerial vehicle-mounted multispectral sensors, such as RedEdge-MX, S110 NIR, Sequioa, and P4M, on September 14 and September 15, 2020, aerial images were taken, once in the morning and in the afternoon, a total of 4 times, and reflectance and vegetation index were calculated and compared. In the case of reflectance, the time-series coefficient of variation of all sensors showed an average value of about 10% or more, indicating that there is a limit to its use. The coefficient of variation of the vegetation index by sensor for the crop test group showed an average value of 1.2 to 3.6% in the crop experimental sites with high vitality due to thick vegetation, showing variability within 5%. However, this was a higher value than the coefficient of variation on a clear day, and it is estimated that the weather conditions such as clouds were different in the morning and afternoon during the experiment period. It is thought that it is necessary to establish and implement a UAV flight plan. As a result of comparing the NDVI between the multi-spectral sensors of the unmanned aerial vehicle, in this experiment, it is thought that the RedEdeg-MX sensor can be used together without special correction of the NDVI value even if several sensors of the same type are used in a stable light environment. RedEdge-MX, P4M, and Sequioa sensors showed a linear relationship with each other, but supplementary experiments are needed to evaluate joint utilization through off-set correction between vegetation indices.

Effect of Various LED Light Wavelengths on the Growth of Food-borne Bacteria (다양한 파장의 LED 조사가 주요 식중독 미생물의 생장에 미치는 영향)

  • Lee, Ji-Eun;Xu, Xiaotong;Jeong, So-Mi;Kim, Su-Ryong;Kim, Han-Ho;Kang, Woo-Sin;Ryu, Si-Hyeong;Lee, Ga-Hye;Ahn, Dong-Hyun
    • Journal of Life Science
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    • v.31 no.10
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    • pp.905-912
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    • 2021
  • In this study, four common food-borne bacteria, namely, Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, and Bacillus subtilis, were targeted via irradiation with 270 nm UV C-LED, 365 nm UV A-LED, 465~475 and 620~630 nm visible-LED, and 850 and 5,000~7,000 nm infrared-LED light. The effect on the growth of each bacterial species was investigated. In the case of 270 nm UV C-LED, all four strains showed inhibitory effects compared with the control group when irradiated for 10 or 30 min. Furthermore, when irradiated with 365 nm UV A-LED for 1 or 3 hr, B. subtilis showed 100% growth inhibition. When irradiated with 465~475 nm visible-LED for 1 hr, all four strains showed no significant difference from the control group but showed significant growth inhibition when irradiated for 3 hr. S. aureus and B. subtilis treated with 620~630 nm visible-LED; S. typhimurium and S. aureus treated with 850 nm infrared-LED; and E. coli, S. typhimurium, and S. aureus treated with 5,000~7,000 nm infrared-LED were confirmed to significantly proliferate compared with the control group. The results of this experiment show the potential of the use of various LED light sources as a food preservation and application technology by examining their effect on the inhibition and growth of food-borne bacteria and by grasping the characteristics of each wavelength.

Data collection strategy for building rainfall-runoff LSTM model predicting daily runoff (강수-일유출량 추정 LSTM 모형의 구축을 위한 자료 수집 방안)

  • Kim, Dongkyun;Kang, Seokkoo
    • Journal of Korea Water Resources Association
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    • v.54 no.10
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    • pp.795-805
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    • 2021
  • In this study, after developing an LSTM-based deep learning model for estimating daily runoff in the Soyang River Dam basin, the accuracy of the model for various combinations of model structure and input data was investigated. A model was built based on the database consisting of average daily precipitation, average daily temperature, average daily wind speed (input up to here), and daily average flow rate (output) during the first 12 years (1997.1.1-2008.12.31). The Nash-Sutcliffe Model Efficiency Coefficient (NSE) and RMSE were examined for validation using the flow discharge data of the later 12 years (2009.1.1-2020.12.31). The combination that showed the highest accuracy was the case in which all possible input data (12 years of daily precipitation, weather temperature, wind speed) were used on the LSTM model structure with 64 hidden units. The NSE and RMSE of the verification period were 0.862 and 76.8 m3/s, respectively. When the number of hidden units of LSTM exceeds 500, the performance degradation of the model due to overfitting begins to appear, and when the number of hidden units exceeds 1000, the overfitting problem becomes prominent. A model with very high performance (NSE=0.8~0.84) could be obtained when only 12 years of daily precipitation was used for model training. A model with reasonably high performance (NSE=0.63-0.85) when only one year of input data was used for model training. In particular, an accurate model (NSE=0.85) could be obtained if the one year of training data contains a wide magnitude of flow events such as extreme flow and droughts as well as normal events. If the training data includes both the normal and extreme flow rates, input data that is longer than 5 years did not significantly improve the model performance.

A Study on the Effect of Applying Water Seepage Lowering Method Using Swelling Waterstop for Expansion Joint in the Concrete Dam (콘크리트 댐에서 수축이음부의 수팽창성 차수재를 이용한 침투저감 공법 적용효과 연구)

  • Han, Kiseung;Lee, Seungho;Kim, Sanghoon;Kim, Sejin;Pai, Sungjin
    • Journal of the Korean GEO-environmental Society
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    • v.22 no.10
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    • pp.21-29
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    • 2021
  • Most concrete gravity-type dams in and out of the country were constructed by column method to control cracks caused by concrete hydration heat generated during construction, resulting in a certain level of leakage after impoundment through various causes, such as contraction joints and construction joints. However, due to the characteristics of concrete structures that shrink and expand according to temperature, concrete dams have vertical joints and drains to allow penetration. PVC waterproof shows excellent effects in completion of the dam, which however increases the possibility of interfacial failure due to different thermal expansion. Other causes of penetration may include problems with quality control during installation, generation of cracks due to heat of hydration of concrete, waterproofing methods, etc. In the case of Bohyunsan Dam in Yeongcheon, North Gyeongsang Province, the amount of drainage in the gallery was checked and underwater, and it was confirmed that there are many penetrations from drainage holes connected to vertical joints, and that some of the PVC waterproofs are not fully operated. As a new method to prevent penetration through vertical joints, D.S.I.M. (Dam Sealing Innovation Method) developed by World E&C was applied to Bohyunsan Dam and checked the amount of drainage in the gallery. As a result of first testing three most leaking vertical joints, the drain in the gallery was reduced by 87% on the average and then applied to the remaining 13 locations, which showed a 83% reduction effect based on the total drain in the gallery. Summing up these results, it was found that D.S.I.M. preventing water leakage from the upstream face is a valid construction method to reduce the water see-through and penetration quantity seen in downstream faces of concrete dams. If D.S.I.M. is applied to other concrete dams at domestic and abroad, it is expected that it will be very effective to prevent water leakage through vertical joints that are visible from downstream faces.

Correlation Analysis between Damage of Expansion Joints and Response of Deck in RC Slab Bridges (RC 슬래브교의 신축이음 손상과 바닥판 응답과의 상관관계 분석)

  • Jung, Hyun-Jin;An, Hyo-Joon;Park, Ki-Tae;Jung, Kyu-San;Kim, Yu-Hee;Lee, Jong-Han
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.6
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    • pp.245-253
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    • 2021
  • RC slab bridges account for the largest portion of deteriorated bridges in Korea. However, most RC slabs are not included in the first and second classes of bridges, which are subject to bridge safety management and maintenance. The highest damaged components in highway bridges are the subsidiary facilities including expansion joints and bearings. In particular, leakage through expansion joints causes deterioration and cracks of concrete and exposure of reinforced bars. Therefore, this study analyzed the effect of adhesion damage at expansion joints on the response of the deck in RC slab bridges. When the spacing between the expansion joints at both ends was closely adhered, cracks occurred in the concrete at both ends of the deck due to the resistance rigidity at the expansion joints. Based on the response results, the correlation analysis between displacements in the longitudinal direction of the expansion joint and concrete stress at both ends of the deck for each damage scenario was performed to investigate the effect of the occurrence of damage on the bridge behavior. When expansion joint devices at both sides were damaged, the correlation between displacement and stress showed a low correlation of 0.18 when the vehicles proceeded along all the lanes. Compared with those in the intact state, the deflections of the deck in the damaged case at both sides showed a low correlation of 0.34 to 0.53 while the vehicle passed and 0.17 to 0.43 after the vehicle passed. This means that the occurrence of cracks in the ends of concrete changed the behavior of the deck. Therefore, data-deriven damage detection could be developed to manage the damage to expansion joints that cause damage and deterioration of the deck.

A Study on the Protection of Personal Information in the Medical Service Act (의료법의 개인정보보호에 관한 연구)

  • Sung, Soo-Yeon
    • The Korean Society of Law and Medicine
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    • v.21 no.2
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    • pp.75-103
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    • 2020
  • There is a growing voice that medical information should be shared because it can prepare for genetic diseases or cancer by analyzing and utilizing medical information in big data or artificial intelligence to develop medical technology and improve patient care. The utilization and protection of patients' personal information are the same as two sides of the same coin. Medical institutions or medical personnel should take extra caution in handling personal information with high environmental distinct characteristics and sensitivity, which is different from general information processors. In general, the patient's personal information is processed by medical personnel or medical institutions through the processes of collection, creation, and destruction. Still, the use of terms related to personal information in the Medical Service Act is jumbled, or the scope of application is unclear, so it relies on the interpretation of precedents. For the medical personnel or the founder of the medical institution, in the case of infringement of Article 24(4), it cannot be regarded that it means only medical treatment information among personal information, whether or not it should be treated the same as the personal information under Article 23, because the sensitive information of patients is recorded, saved, and stored in electronic medical records. Although the prohibition of information leakage under Article 19 of the Medical Service Act has a revision; 'secret' that was learned in business was revised to 'information', but only the name was changed, and the benefit and protection of the law is the same as the 'secret' of the criminal law, such that the patient's right to self-determination of personal information is not protected. The Privacy Law and the Local Health Act consider the benefit and protection of the law in 'information learned in business' as the right to self-determination of personal information and stipulate the same penalties for personal information infringement such as leakage, forgery, alteration, and damage. The privacy regulations of the Medical Service Act require that the terms be adjusted uniformly because the jumbled use of terms can confuse information subjects, information processors, and shows certain limitations on the protection of personal information because the contents or scope of the regulations of the Medical Service Law for special corporations and the Privacy Law may cause confusion in interpretation. The patient's personal information is sensitive and must be safely protected in its use and processing. Personal information must be processed in accordance with the protection principle of Privacy Law, and the rights such as privacy, freedom, personal rights, and the right to self-determination of personal information of patients or guardians, the information subject, must be guaranteed.