• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.167-174
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• 2019

A process-oriented crop growth model can simulate the biophysical process of rice under diverse environmental and management conditions, which would make it more versatile than an empirical crop model. In the present study, we examined chronology and background of the development of the rice growth models in Korea, which would provide insights on the needs for improvement of the models. The rice crop growth models were introduced in Korea in the late 80s. Until 2000s, these crop models have been used to simulate the yield in a specific area in Korea. Since then, improvement of crop growth models has been made to take into account biological characteristics of rice growth and development in more detail. Still, the use of the crop growth models has been limited to the assessment of climate change impact on crop production. Efforts have been made to apply the crop growth model, e.g., the CERES-Rice model, to develop decision support system for crop management at a farm level. However, the decision support system based on a crop growth model was attractive to a small number of stakeholders most likely due to scarcity of on-site weather data and reliable parameter sets for cultivars grown in Korea. The wide use of the crop growth models would be facilitated by approaches to extend spatial availability of reliable weather data, which could be either measured on-site or estimates using spatial interpolation. New approaches for calibration of cultivar parameters for new cultivars would also help lower hurdles to crop growth models.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.208-220
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• 2019

The seasonality of leaf fall has important implications for understanding the response of trees' phenology to climate change. In this study, we quantified the leaf fall pattern with a model to estimate the timing and speed of leaf litter according to species and considered the nutrient use strategy of canopy species. In the autumns of 2015 and 2016, leaf litter was collected periodically using 36 litter-traps from the deciduous forests in Gwangneung and sorted by species. The seasonal leaf fall pattern was estimated using the non-linear regression model of Dixon. Additionally, the resorption rate was calculated by analyzing the nitrogen concentration of the leaf litter at each collection time. The leaf litter generally began in early October and ended in mid-November depending on the species. At the peak time (T50) of leaf fall, on average, Carpinus laxiflora was first, and Quercus serrata was last. The rate of leaf fall was fastest (18.6 days) for Sorbus alnifolia in 2016 and slowest (40.8 days) for C. cordata in 2015. The nitrogen resorption rates at T50 were 0.45% for Q. serrata and 0.48% for C. laxiflora, and the resorption rate in 2015 with less precipitation was higher than in 2016. Since falling of leaf litter is affected by environmental factors such as temperature, precipitation, photoperiod, and $CO_2$ during the period attached foliage, the leaf fall pattern and nitrogen resorption differed year by year depending on the species. If we quantify the fall phenomena of deciduous trees and analyze them according to various conditions, we can predict whether the changes in leaf fall timing and speed due to climate change will prolong or shorten the growth period of trees. In addition, it may be possible to consider how this affects their nutrient use strategy.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.175-186
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• 2019

Efforts have been made to introduce the climate smart agriculture (CSA) for adaptation to future climate conditions, which would require collection and management of site specific meteorological data. The objectives of this study were to identify requirements for construction of agricultural meteorology information service system (AMISS) using technologies that lead to the fourth industrial revolution, e.g., internet of things (IoT), artificial intelligence, and cloud computing. The IoT sensors that require low cost and low operating current would be useful to organize wireless sensor network (WSN) for collection and analysis of weather measurement data, which would help assessment of productivity for an agricultural ecosystem. It would be recommended to extend the spatial extent of the WSN to a rural community, which would benefit a greater number of farms. It is preferred to create the big data for agricultural meteorology in order to produce and evaluate the site specific data in rural areas. The digital climate map can be improved using artificial intelligence such as deep neural networks. Furthermore, cloud computing and fog computing would help reduce costs and enhance the user experience of the AMISS. In addition, it would be advantageous to combine environmental data and farm management data, e.g., price data for the produce of interest. It would also be needed to develop a mobile application whose user interface could meet the needs of stakeholders. These fourth industrial revolution technologies would facilitate the development of the AMISS and wide application of the CSA.

• Korean Journal of Heritage: History & Science
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• v.40
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• pp.307-323
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• 2007

One of the distinguishing features of late Jeosun s Hanshi (poem in Chinese) is the numerous creation of Yeonjachyung Keesokshi (serial poem on folklore) which describes the folk manner and folk way of life in detail. Keesokshi s subject matter is the folklike in general including local features, geography, climate, local production, humanity, social conducts, and daily labor for living as well. By its material characteristics, Keesokshi reflects detailed life conditions of the society members in each levels, and represents the local customs as well as the folk emotions. Among the several kinds of Keesokshis, a Sesi Keesokshi focuses only in reciting the folk customs on each seasonal festival days, and the great numbers of such serial poems appear during the latter part of the Jeosun Dynasty. Its overall background is the transition of artistic trend which came after many social changes such as expansion of realism, uprising national consciousness, shaken status system, and the rising of 'Jeosun si motives in the Hansi history. Moreover, each writers various experiences and their interests in the reality and critical minds of common people contributed a crucial roll in creation of Sesi Keesokshi. 178 of the 584 remaining serial Sesi Keesokshi are written particularly about the folk customs in The Grand Full Moon Festival (the first full moon of a year by the lunar calendar). These Hanshis widely reflect the common ways of living by directly accepting the seasonal folk customs as the subject matters. Especially, close to the reality, these poems positively express the people's simple vigorous lives and create unrestrained lively image by describing the joys and sorrows of the folk ewistence along with their craving. Also, it is notable to have customs such as 'Shil-Ssa-Um' and 'No-gu-ban-kong-yang' as subjects for its rarity in other literatures.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.5
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• pp.208-214
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• 2019

The glass of $BaO-GeO_2-La_2O_3-ZnO$ system with a transmittance of more than 75 % at mid-wave infrared (MWIR) region in the range of $3{\mu}m$ to $5{\mu}m$ is manufactured and its property is evaluated. After selecting construction that can melt glass through flow button test, $BaO-GeO_2-La_2O_3$ system where 10 mol%, 20 mol% of ZnO were added respectively were melted at $1350^{\circ}C$ for 1 hour and $BaO-GeO_2-La_2O_3$ system of glass was manufactured. Among them, with 20 mol% of ZnO, 16 mol% BaO-56 mol% $GeO_2-8mol%$ $La_2O_3-16mol%$ ZnO system of glass was found to has less than $660^{\circ}C$ of glass transition temperature, more than 1.70 of refractive index, and more than 530 of knoop hardness. Therefore, it is concluded that glass of $BaO-GeO_2-La_2O_3-ZnO$ system of glass with 20 mol% ZnO has good melting conditions at low temperatures and excellent optical properties, thus, can be utilized for special optical materials field.

• Korean Journal of Heritage: History & Science
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• v.40
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• pp.271-306
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• 2007

One of the distinguishing features of late Jeosun's Hanshi (poem in Chinese) is the numerous creation of Yeonjachyung Keesokshi (serial poem on folklore) which describes the folk manner and folk way of life in detail. Keesokshi's subject matter is the folklike in general including local features, geography, climate, local production, humanity, social conducts, and daily labor for living as well. By its material characteristics, Keesokshi reflects detailed life conditions of the society members in each levels, and represents the local customs as well as the folk emotions. Among the several kinds of Keesokshis, a Sesi Keesokshi focuses only in reciting the folk customs on each seasonal festival days, and the great numbers of such serial poems appear during the latter part of the Jeosun Dynasty. Its overall background is the transition of artistic trend which came after many social changes such as expansion of realism, uprising national consciousness, shaken status system, and the rising of 'Jeosunsi' motives in the Hansi history. Moreover, each writer's various experiences and their interests in the reality and critical minds of common people contributed a crucial roll in creation of Sesi Keesokshi. 178 of the 584 remaining serial Sesi Keesokshi are written particularly about the folk customs in The Grand Full Moon Festival (the first full moon of a year by the lunar calendar). These Hanshis widely reflect the common ways of living by directly accepting the seasonal folk customs as the subject matters. Especially, close to the reality, these poems positively express the people's simple vigorous lives and create unrestrained lively image by describing the joys and sorrows of the folk existence along with their craving. Also, it is notable to have customs such as 'Shil-Ssa-Um' and 'No-gu-ban-kong-yang' as subjects for its rarity in other literatures.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.2
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• pp.29-37
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• 2019

Purpose DMIDR(Discovery Molecular Imaging Digital Ready, General Electric Healthcare, USA) is a PET/CT scanner designed to allow application of PSF(Point Spread Function), TOF(Time of Flight) and Q.Clear algorithm. Especially, Q.Clear is a reconstruction algorithm which can overcome the limitation of OSEM(Ordered Subset Expectation Maximization) and reduce the image noise based on voxel unit. The aim of this paper is to evaluate the performance of reconstruction algorithms and optimize the algorithm combination to improve the accurate SUV(Standardized Uptake Value) measurement and lesion detectability. Materials and Methods PET phantom was filled with $^{18}F-FDG$ radioactivity concentration ratio of hot to background was in a ratio of 2:1, 4:1 and 8:1. Scan was performed using the NEMA protocols. Scan data was reconstructed using combination of (1)VPFX(VUE point FX(TOF)), (2)VPHD-S(VUE Point HD+PSF), (3)VPFX-S (TOF+PSF), (4)QCHD-S-400((VUE Point HD+Q.Clear(${\beta}-strength$ 400)+PSF), (5)QCFX-S-400(TOF +Q.Clear(${\beta}-strength$ 400)+PSF), (6)QCHD-S-50(VUE Point HD+Q.Clear(${\beta}-strength$ 50)+PSF) and (7)QCFX-S-50(TOF+Q.Clear(${\beta}-strength$ 50)+PSF). CR(Contrast Recovery) and BV(Background Variability) were compared. Also, SNR(Signal to Noise Ratio) and RC(Recovery Coefficient) of counts and SUV were compared respectively. Results VPFX-S showed the highest CR value in sphere size of 10 and 13 mm, and QCFX-S-50 showed the highest value in spheres greater than 17 mm. In comparison of BV and SNR, QCFX-S-400 and QCHD-S-400 showed good results. The results of SUV measurement were proportional to the H/B ratio. RC for SUV is in inverse proportion to the H/B ratio and QCFX-S-50 showed highest value. In addition, reconstruction algorithm of Q.Clear using 400 of ${\beta}-strength$ showed lower value. Conclusion When higher ${\beta}-strength$ was applied Q.Clear showed better image quality by reducing the noise. On the contrary, lower ${\beta}-strength$ was applied Q.Clear showed that sharpness increase and PVE(Partial Volume Effect) decrease, so it is possible to measure SUV based on high RC comparing to conventional reconstruction conditions. An appropriate choice of these reconstruction algorithm can improve the accuracy and lesion detectability. In this reason, it is necessary to optimize the algorithm parameter according to the purpose.

• Korean Journal of Ecology and Environment
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• v.51 no.4
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• pp.331-344
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• 2018

Lotic organisms in streams are affected by natural and anthropogenic disturbances such as increase of heavy rainfall event caused by climate change and flow regime change caused by weir constructions. Based on domestic and foreign literature, 157 Korean benthic macroinvertebrate taxa were selected species as potential lotic candidates. Three shoreline sites (total 54 samples) were surveyed consecutively before ('08~'09), during ('10~'12) and after ('13~'16) the construction of the weirs (Gangcheon, Yeoju and Ipo weir) in the Namhan-River for tracing changes of lotic communities. As a result, water flow of the Ipo-wier and water quality variables such as T-N, T-P, BOD5, etc. of the weir section revealed no significant changes. Physical habitat conditions such as the flow velocity and streambed substrate evidently changed. Particulary, flow velocity measured at sampling points along with each microhabitat drastically decreased and particle size of streambed substrate steadily decreased after weir constructions. Lotic organisms also decreased after construction, especially Hydropsychidae (insecta: Trichoptera) acutely decreased from $3,526ind.\;m^{-2}$ to $2ind.\;m^{-2}$ As a result of CCA, lotic species such as Hydropsyche valvata, Hydropsyche kozhantschikovi, Cheumatopsyche brevilineata, Cheumatopsyche KUa, Macrostemum radiatum, etc. correlated with the flow velocity, streambed substrate. Therefore, the decrease of the flow velocity and substrate size after weir construction seemed to be closely related to the decrease of the individual abundances of the lotic organisms independently of water quality. In order to evaluate the influence of the ecosystem on the flow regime change more accurately, it is necessary to study the indicator species based on the resistance or preference of the flow.

• Korean Journal of Heritage: History & Science
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• v.39
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• pp.165-189
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• 2006

The purpose of this study is to examine process and organization of local government-managed construction by reviewing official documents and materials in regard to the official residences and castles officially constructed in Dongnae in the 19c Chosun Dynasty. Results of this study can be described as follows. 1) The construction of official residences requires exchanges of official documents among upper and lower governmental agencies concerned. Previously prepared for some 1 or 2 months, the construction was proceeded through proceeded from Paok to Gaegi, Ipju, Sangryang, Gaeok and to Iptaek. Such construction was carried out independently and concurrently Gijang and Yangsan neighboring Dongnae provided cooperation by way of supplying labor and timbers. 2) Dongnaebu castle was constructed under local autonomy system, like other government-oriented works, as governor of Dongnae became responsible for defending such establishment in 1739. The castle was built up in 1731 as an establishment with 6 gated and 15 forts. Directly controlled by governor of Dongnae, the castle continued to be partially repaired until the 19th century. Under the regime of Daewongun, the castle was enlarged and extended for military strengthening. Besides the gate having double-gated structure for the outside wall, the other five gates came to have bastions and 30 forts were additionally established, dramatically changing the structure of the castle as whole. 3) Government-managed construction was often implemented by an organization whose members included local government officials, lower administrative agencies and local influential persons. The construction of official residences was implemented by Gamyeokdogam which was headed by Jwasu of Hyangcheong. In the construction, chief of military officials became supervisor, who was responsibly supported by Saekri. The construction of castled were divided into several works, for example, establishments of fortress, tower gate and quarrying stone were implemented by the organization of Paejang, Gamkwan and Saekri. As a military official, Gamkwan supervised the construction. Saekri was in charge of related internal affairs. Paejang was an technical expert leading several workers. The construction of castles in 1870 were organized as a general rule having particularity of social conditions on Dongnae.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.2
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• pp.20-24
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• 2019

Purpose Molecular Breast Imaging (MBI) scan is used in nuclear medicine, for which $^{99m}Tc-sestaMIBI$ is administered by intravenous injection. However, the breast uptake rate of $^{99m}Tc-sestaMIBI$ is less than 1% of the total dose administered, relying on blood flow conditions of organs. The purpose of this study is to evaluate the impact of changes to body temperature on the uptake of $^{99m}Tc-sestaMIBI$ in breast tissue. Materials and Methods We investigated 30 breast cancer patients who performed more than one follow-up MBI scan. All scans were acquired by Discovery 750B (Genral Electric Healthcare, USA). $^{99m}Tc-sestaMIBI$ injected with 740 MBq (20 mCi), after 60 minutes, gained bilateral breast CC (CranioCaudal), MLO (Medio Lateral Oblique) View. The follow-up examination was then classified into 15 body temperature control group and 15 body temperature non-control group, and gained breast image in the same way as before. The breast uptake rate was analyzed in the MLO View of the opposite side of the lesion, and blind images were evaluated. Results The breast uptake rate increased by 30.31% in the body temperature control group and it was statistically significant(P<0.05), and 0.96% in the body temperature non-control group, and it was not statistically significant(P=0.955). There was a significant difference in the uptake rate between the body temperature control and the non-control group of P value of 0.01. Evaluation of blind images showed significant results in terms of the quality of the images. Conclusion Increased breast tissue uptake was observed when the subject was kept warm. When the body temperature was raised after injection, dilation of the peripheral blood vessels can be achieved. As a result, the blood flow became smooth and the breast uptake rate increased. In addition, an increase in breast tissue uptake will improve the quality of images.