• Food Engineering Progress
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• v.14 no.4
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• pp.307-315
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• 2010

The safety and security of food supply should be one of the primary responsibilities of any government. Estimation of nation's food commodity intakes is important to control the potential risks in food systems since food hazards are often associated with quality and safety of food commodities. The food intake databases provided by Korea National Health and Nutrition Examination Survey (KNHANES) are good resources to estimate the demographic data of intakes of various food commodities. A limitation of the KNHANES databases, however, is that the food intakes surveyed are not based on commodities but ingredients and their mixtures. In this study, reasonable calculation strategies were applied to convert the food intakes of the ingredients mixtures from the KNHANES into food commodity intakes. For example, Perilla leaf consumed with meat, raw fish, and etc. in Korean diets was used to estimate its Korean intakes and develop algorithms for demographic analysis. Koreans have consumed raw, blanched, steamed, and canned perilla leaf products. The average daily intakes of the perilla leaf were analyzed demographically, for examples, the intakes by gender, age, and etc. The average daily intakes of total perilla leaf were 2.03${\pm}$0.27 g in 1998, 2.11${\pm}$0.26 g in 2001, 2.29${\pm}$0.27 g in 2005, 2.75${\pm}$0.35 g in 2007, and 2.27${\pm}$0.20 g in 2008. Generally, people equal to or over 20 years of age have shown higher perilla leaf intakes than people below 20. This study would be contributed to the estimation of intakes of possible chemical contaminants such as residual pesticides and subsequent analysis for their potential risk.

• Journal of Climate Change Research
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• v.2 no.4
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• pp.237-251
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• 2011

This study presents a review on the recent climate change over the Korean peninsula, which has experienced a significant change due to the human-induced global warming more strongly than other regions. The recent measurement of carbon dioxide concentrations over the Korean peninsula shows a faster rise than the global average, and the increasing trend in surface temperature over this region is much larger than the global mean trend. Recent observational studies reporting the weakened cold extremes and intensified warm extremes over the region support consistently the increase of mean temperature. Surface vegetation greenness in spring has also progressed relatively more quickly. Summer precipitation over the Korean peninsula has increased by about 15% since 1990 compared to the previous period. This was mainly due to an increase in August. On the other hand, a slight decrease in the precipitation (about 5%) during Changma period (rainy season of the East Asian summer monsoon), was observed. The heavy rainfall amounts exhibit an increasing trend particularly since the late 1970s, and a consecutive dry-day has also increased primarily over the southern area. This indicates that the duration of precipitation events has shortened, while their intensity became stronger. During the past decades, there have been more stronger typhoons affecting the Korean peninsula with landing more preferentially over the southeastern area. Meanwhile, the urbanization effect is likely to contribute to the rapid warming, explaining about 28% of total temperature increase during the past 55 years. The impact of El Nino on seasonal climate over the Korean peninsula has been well established - winter [summer] temperatures was generally higher [lower] than normal, and summer rainfall tends to increase during El-Nino years. It is suggested that more frequent occurrence of the 'central-Pacific El-Nino' during recent decades may have induced warmer summer and fall over the Korean peninsula. In short, detection and attribution studies provided fundamental information that needed to construct more reliable projections of future climate changes, and therefore more comprehensive researches are required for better understanding of past climate variations.

• Journal of Climate Change Research
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• v.4 no.4
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• pp.305-316
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• 2013

The purpose of this study is to monitor the flux of $CO_2$ between the atmosphere and forest. The main research activities are conducted at Taehwa Mt. (Gangju, Kyeonggi, Korea), The Taehwa site is located 60 km north-east from the center of Seoul Metropolitan Area. The TRF flux tower is in the middle of a Korean Pine (Pinus koraiensis) plantation ($400m{\times}400m$), surrounded by a mixed forest. Eddy covariance method was used for $CO_2$ flux above the forest. $CO_2$ flux was measured from September to November 2011 and March to June 2012. It was found that $CO_2$ fluxes were observed between the atmosphere and forest. $CO_2$ was absorbed by plants through photosynthesis during the day and released during the night. $CO_2$ flux were respectively observed 0.7~0.2, 0.5~0.1, $0.3{\sim}0.1mgCO_2m^{-2}s^{-1}$ in Septem- ber, October, November 2011. $CO_2$ fluxes released by plants in the early morning(00:00~07:30h) and evening(18:00~24:00h) time. But $CO_2$ was absorbed by plants through photosynthesis in the day time(08:00~7:30h).

• 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 Ecology and Environment
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• v.52 no.2
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• pp.126-135
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• 2019

We carried out a literature review of fish food sources research in the coast - estuary areas of Korean peninsula for the last fifty years(1969~2018). A total of 101 research papers were reviewed, of which 81 were published in domestic journals, 7 were puliched in domestic reports and 14 were published in international journals. When divided into the decade periods, 21 papers (19.4%) between 1990 and 1999 and 26 papers (24.1%) between 2000 and 2009, and 42 papers (48.1%) were published in 2010 and 2018, respectively. When divided into the survey area by a bearing (East sea, South-East sea, South Sea, and West Sea), 65 papers(69.1%) were carried out in the South Sea. Followed by 13 papers (13.8%) in the East Sea and 8 papers (8.5%) in the West Sea and the South-East Sea, respectively. The surveyed area was dominant in Gwangyang Bay (18 papers; 24.3%), followed by Gadeok-do (8 papers; 10.8%). Of the diversity indices, 14 indices were used to calculate the ecological status. The dominant indices were IRI(Index of relative importance), Pi(Prey-specific abundance) followed by E (electivity index) and Bi (dietary breadth index). A total of 11 statistical methods were used to find feeding strategy. The correlation analysis and Bray-Curtis similarity matrix were applied most frequently. In terms of ecological research topics, the papers focused on seasonal or spatial differences before 2000. Since 2000, specifically, the international journal papers have been published based on competition, sympatric, niche overlap and other ecological topics.

• (The)Study of the Eastern Classic
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• no.67
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• pp.345-378
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• 2017

In the scriptures of "$Ch{\bar{u}}n-qi{\bar{u}}$(春秋)", the expression method of '$Ch{\bar{u}}n-w{\acute{a}}ng-zh{\bar{e}}ng-yu{\grave{e}}$(春王正月 : It's spring. It's the first month regulated by the king.)' was used as Jì-yuè-fǎ(紀月法 : the rules to determine the first month(正月)), the month of winter solstice was regarded as the first month of a year, and three years since then were named as $Ch{\bar{u}}n$(春 : spring). With regard to this "$Ch{\bar{u}}n-qi{\bar{u}}$"Wáng-lì("春秋"王曆 : the calendar regulated by the king of $Zh{\bar{o}}u$(周) dynasty in "$Ch{\bar{u}}n-qi{\bar{u}}$"), depending on whether Confucius(孔子) changed and recorded the names of the months and the season or not, there were three different arguments; the theory that 'Confucius changed the names of both the months and the season'(孔子改月 改時說), the view that 'Confucius changed the name of the season, not the names of the months'(孔子不改月 改時說), and then the theory that 'Confucius changed neither the names of the months nor the name of the season'(孔子不改月 不改時) since Song(宋) dynasty. The first view was taken by $Hh{\acute{u}}-{\bar{a}}n-gu{\acute{o}}$(胡安國) and $C{\grave{a}}i-ch{\acute{e}}n$(蔡沈), and the second theory was mentioned by Chéng-yí(程?) and Zhū-zǐ(朱子). The advocates of the third view had become remarkable since Ming(明) dynasty, and one of representatives was Wàng-yáng-míng(王陽明). All of them based their arguments on ancient scriptures and Confucian legal books, and there were cases of taking the same records as the support for different opinions. Confucius' so-called 'Chūn-qiū-bǐ-fǎ(春秋筆法 : the method to describe historical facts by making clear discrimination between right and wrong)' and '$Sh{\grave{u}}-{\acute{e}}r-b{\grave{u}}-zu{\grave{o}}$(述而不作 : the attitude to succeed virtuous men's achievements and only explain and describe them not creating and adding new contents)' could come from thoughts of $Z{\bar{u}}n-w{\acute{a}}ng$(尊王 : to respect the king with the virtues of benevolence, righteousness, propriety, wisdom and sincerity). Therefore, even though Confucius is assumed to have been the writer of "$Ch{\bar{u}}n-qi{\bar{u}}$(春秋)", whether he actually changed and recorded the names of the months and the season in the calendar used in "$Ch{\bar{u}}n-qi{\bar{u}}$" is doubtful. These theories on Confucius's intervention in the calendar of "$Ch{\bar{u}}n-qi{\bar{u}}$" hadn't been discussed as conflicting in reality until Tang(唐) dynasty.

• (The)Study of the Eastern Classic
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• no.49
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• pp.431-459
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• 2012

The purpose of this article is to compare and analyze the conventional expression of Hangul Ganchal in Cheosun Dynasty and Email. Conventional expression is used remarkably in introductions and conclusions. In introduction, it is used for addressing and safety greetings while in conclusion, it is used for closing address and closing words. In Cheosun Dynasty, an envelope of Ganchal only included the details of the receiver because the letter was genuinely delivered by someone who knew the receiver and the sender very well. An envelope of Ganchal is applicable to the screen of the internet which is used for emailing. In an email, we see the name of the sender and the title of the text and once we click the title, we are able to view the text. The difference between the Ganchal and the email was reflected on how the receiver's detail showed on Ganchal and the email show the sender's details. In a case of addressing in a letter while using the conventional expression, we can see how we use "To~" in humble term and " ~께" in a honorific term. We confirmed that the conventional expression has not yet settled in both of the Gnachal and email for the seasonal greetings. The safety greetings comprised with both of the senders' and receivers' latest updates. In Ganchal, this composition is well described conventionally, whereas in emails, only the receivers' latest news are written but the senders' latest updates are hard to be seen throughout the text. In Ganchal's closing section, the closing address and closing words were expressed conventionally. However, in the case of email; those were again hard to be found throughout. To conclude, in Ganchal the conventional expression was developed and placed in 16thcentury(Sun-eon) when there was a focus in our native language. In 17thcentury(Hyeon-eon), it stood still for a sometime and moved on to 19thcentury(Jing-eon) when there was a strong in fluence of Hangul Ganchal, which resulted in regression to the conservative expression. In general, we are able to confirm that the conventional expression is slowly disappearing.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.4
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• pp.312-326
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• 2020

Generation of weather forecasts at 100 m resolution through a statistical downscaling process was implemented by Korea Meteorological Administration Post- Processing (KMAPP) system. The KMAPP data started to be used in various industries such as hydrologic, agricultural, and renewable energy, sports, etc. Cheorwon area and Jeonbuk area have horizontal planes in a relatively wide range in Korea, where there are many complex mountainous areas. Cheorwon, which has a large number of in-situ and remotely sensed phenological data over large-scale rice paddy cultivation areas, is considered as an appropriate area for verifying KMAPP prediction performance in agricultural areas. In this study, the performance of predicting KMAPP temperature changes according to ecological changes in agricultural areas in Cheorwon was compared and verified using KMA and National Center for AgroMeteorology (NCAM) observations. Also, during the heat wave in Jeonbuk Province, solar radiation forecast was verified using Automated Synoptic Observing System (ASOS) data to review the usefulness of KMAPP forecast data as input data for application models such as livestock heat stress models. Although there is a limit to the need for more cases to be collected and selected, the improvement in post-harvest temperature forecasting performance in agricultural areas over ordinary residential areas has led to indirect guesses of the biophysical and phenological effects on forecasting accuracy. In the case of solar radiation prediction, it is expected that KMAPP data will be used in the application model as detailed regional forecast data, as it tends to be consistent with observed values, although errors are inevitable due to human activity in agricultural land and data unit conversion.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.11 no.4
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• pp.158-164
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• 2006

Yongdam Lake is the fifth largest artificial lake in Korea newly formed by the first impounding the Yongdam Multi-purpose Dam on December, 2002. Yongdam Lake, with her total water storage of 820 million M/T, is located at the roof-top region of the streams flowing into the just-constructed new Saemankeum Lake. Seasonal succession of phytoplakton in Yongdam Lake might affect cyanobacterial blooms in Saemankeum Lake by inoculating seasonal dominants. During 2002-2003 when the first impounding after the construction of Yongdam Multi-purpose Dam was still undergoing, summer cyanobacterial blooms by Anabaena, Microcystis, and Aphanizomenon were observed. Among these three, filamentous Anabaena is well known to have its species with $N_2-fixing$ ability and special cells such as heterocysts and akinetes as well as the vegetative cells. We established a clonal culture of Anabaena spiroides v. crasse (KNU-YD0310) from the live water samples collected at the bloom site of Yongdam Lake. The N- and P-nutrient requirement of the KNU-YD0310 was explored by the experimental cultivation of the laboratory strain. Ratio of heterocysts to vegetative cells increased as N-deficiency extended with its maximum at $N_2-fixing$ condition. The strain KNU-YD0310 exhibited considerable growth under N-limiting conditions while its growth was proportional to the initial phosphate-P concentration under P-deficient conditions. Under P-limiting conditions akinete density increased, which could be interpreted as an adaptation strategy to survive severe environment by transforming into resting stage. The above eco-physiological characteristics of Anabaena spiroides v. crassa might be useful as an ecological criterion in controlling cyanobacterial blooms at Shaemankeum Lake in near future.