• Title/Summary/Keyword: Time trend analysis

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A Proposal for Promotion of Research Activities by Analysis of KOSEF's Basic Research Supports in Animal Resources Science Field (한국과학재단의 동물자원과학 분야의 기초연구지원 추이분석을 통한 연구활동지원 활성화 제언)

  • Min, T.S.;Park, S.H.;Kim, S.Y.;Kim, Y.Y.;Lee, H.T.;Han, In-K.
    • Journal of Animal Science and Technology
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    • v.47 no.1
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    • pp.115-132
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    • 2005
  • This research was conducted to make suggestions for the promotion of research activities in the field of animal resources sciences, and we evaluated the research funding trend and the present status of research funding offered by KOSEF in this field. Comparative portion of the number of research projects and grants in this field to other fields has a tendency to be decreased year by year except recent few years. Researchers in this field have received more research funding from the group-based program than from the individual-based program. Also, they have received less money(per project) than did researchers in the fields of general agricultural sciences and other science and technology. Researchers in this field ranges from 43 to 51 years of age and showed 48 years of average age. It was found that researchers who has been funded in the field of animal resources sciences have showed tendency of publication of more articles to SCI journals in recent 5 years. The strong points of the animal resources of agricultural sciences field in South Korea include: lots of researchers, the establishment of research infra-structure, the excellence in research competitiveness and technology level. However, its weaknesses are: a lack of leadership in relevant societies and institutes, a predicted shortfall of researchers in the next generation and insufficient research productivity. The opportunities include: increasing the importance of the biotechnology industry, activating international cooperation researches and exploring the multitude of possible research areas to be studied. However, some concerns still exist, such as threats from developed countries for the government to open the agricultural market, the reduction of the number of full-time farms and intensification of needs for economic and social effects. The diverse actions and systems based upon the strongpoint, weakness, opportunity and threats above-mentioned are required to encourage research activities in the field of animal resources of agricultural sciences in Korea In addition, researchers in this fields would make an effort to keep pace with international society as well as domestic demands.

Study on Characteristics of Change in Calorific Value and Carbon Emission Factor of Domestic Petroleum Energy Source (국내 석유계 에너지원의 열량 및 탄소배출계수 변화 특성 연구)

  • Doe, Jin-woo;Lim, Wan-gyu;Kang, Hyung-kyu;Hwang, In-ha;Ha, Jong-han;Na, Byung-ki
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.4
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    • pp.1046-1057
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    • 2017
  • Country-specific emission factors should be developed and used instead of IPCC defaults to improve national GHG inventories to Tier 2 and above. Since the country-specific emission factors depend on the type of energy source, energy process, and time trend, identifying the value of each energy source is an important part of building an accurate inventory. In this study, calorific value and carbon emission factor for petroleum energy sources on the basis of calorific value conversion standard for energy source, which are notified in Korea, are collected by 2013 and 2016, and calorific value, carbon content and carbon emission factor And a comparative analysis was conducted. In addition, net calorific values and carbon emission factors calculated for each petroleum based energy source are compared with those shown in 2006 IPCC Guideline.

The Characteristics of Submarine Groundwater Discharge in the Coastal Area of Nakdong River Basin (낙동강 유역의 연안 해저지하수 유출특성에 관한 연구)

  • Kim, Daesun;Jung, Hahn Chul
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1589-1597
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    • 2021
  • Submarine groundwater discharge (SGD) in coastal areas is gaining importance as a major transport route that bring nutrients and trace metals into the ocean. This paper describes the analysis of the seasonal changes and spatiotemporal characteristicsthrough the modeling monthly SGD for 35 years from 1986 to 2020 for the Nakdong river basin. In this study, we extracted 210 watersheds and SGD estimation points using the SRTM (Shuttle Radar Topography Mission) DEM (Digital Elevation Model). The average annual SGD of the Nakdong River basin was estimated to be 466.7 m2/yr from the FLDAS (Famine Early Warning Systems Network Land Data Assimilation System) recharge data of 10 km which is the highest resolution global model applicable to Korea. There was no significant time-series variation of SGD in the Nakdong river basin, but the concentrated period of SGD was expanded from summer to autumn. In addition, it was confirmed that there is a large amount of SGD regardless of the season in coastal area nearby large rivers, and the trend has slightly increased since the 1980s. The characteristics are considered to be related to the change in the major precipitation period in the study area, and spatially it is due to the high baseflow-groundwater in the vicinity of large rivers. This study is a precedentstudy that presents a modeling technique to explore the characteristics of SGD in Korea, and is expected to be useful as foundational information for coastal management and evaluating the impact of SGD to the ocean.

Effects of Bacillus-based probiotics on growth performance, nutrient digestibility, and intestinal health of weaned pigs

  • Mun, Daye;Kyoung, Hyunjin;Kong, Myunghwan;Ryu, Sangdon;Jang, Ki Beom;Baek, Jangryeol;Park, Kyeong Il;Song, Minho;Kim, Younghoon
    • Journal of Animal Science and Technology
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    • v.63 no.6
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    • pp.1314-1327
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    • 2021
  • Bacillus is characterized by the formation of spores in harsh environments, which makes it suitable for use as a probiotic for feed because of thermostability and high survival rate, even under long-term storage. This study was conducted to investigate the effects of Bacillus-based probiotics on growth performance, nutrient digestibility, intestinal morphology, immune response, and intestinal microbiota of weaned pigs. A total of 40 weaned pigs (7.01 ± 0.86 kg body weight [BW]; 28 d old) were randomly assigned to two treatments (4 pigs/pen; 5 replicates/treatment) in a randomized complete block design (block = BW and sex). The dietary treatment was either a typical nursery diet based on corn and soybean meal (CON) or CON supplemented with 0.01% probiotics containing a mixture of Bacillus subtilis and Bacillus licheniformis (PRO). Fecal samples were collected daily by rectal palpation for the last 3 days after a 4-day adaptation. Blood, ileal digesta, and intestinal tissue samples were collected from one pig in each pen at the respective time points. The PRO group did not affect the feed efficiency, but the average daily gain was significantly improved (p < 0.05). The PRO group showed a trend of improved crude protein digestibility (p < 0.10). The serum transforming growth factor-β1 level tended to be higher (p < 0.10) in the PRO group on days 7 and 14. There was no difference in phylum level of the intestinal microbiota, but there were differences in genus composition and proportions. However, β-diversity analysis showed no statistical differences between the CON and the PRO groups. Taken together, Bacillus-based probiotics had beneficial effects on the growth performance, immune system, and intestinal microbiota of weaned pigs, suggesting that Bacillus can be utilized as a functional probiotic for weaned pigs.

Model Design and Applicability Analysis of Interactive Electronic Technical Manual for Planning Stage of Construction Projects (건설공사 기획단계 전자매뉴얼의 적용 모형 구성 및 효과 분석)

  • Kwak, Joong-Min;Kang, Leen-Seok
    • Land and Housing Review
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    • v.12 no.2
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    • pp.121-139
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    • 2021
  • Technical documents in the construction field are changing from paper documents to electronic ones. As a result, the industry witnesses a trend of using portable electronic devices in searching or retrieving necessary information such as relevant regulations. Despite the improvement in the accessibility to general technical documents, a limitation is still found in accessing the electronic documents on the regulations. We see the barrier for field engineers to enhance their technical knowledge. One of major barriers is that videos, animations, and virtual reality information to enhance the visual understanding of technical content related to regulations are not linked. It is the interactive electronic technical manual (IETM) that can address such issues. The IETM is an electronic document system that enables real-time information acquisition while operating in the form of conversations with users by linking multimedia functions to document types such as specifications and guidelines. This study establishes a model of the IETM that can be operated in the planning stage of a construction project. The study also verifies its usability with a hypothetical case study. This study aims to improve the usability of the IETM in the construction project by analyzing the application effect of the IETM using the AHP technique.

A comparison and prediction of total fertility rate using parametric, non-parametric, and Bayesian model (모수, 비모수, 베이지안 출산율 모형을 활용한 합계출산율 예측과 비교)

  • Oh, Jinho
    • The Korean Journal of Applied Statistics
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    • v.31 no.6
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    • pp.677-692
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    • 2018
  • The total fertility rate of Korea was 1.05 in 2017, showing a return to the 1.08 level in the year 2005. 1.05 is a very low fertility level that is far from replacement level fertility or safety zone 1.5. The number may indicate a low fertility trap. It is therefore important to predict fertility than at any other time. In the meantime, we have predicted the age-specific fertility rate and total fertility rate by various statistical methods. When the data trend is disconnected or fluctuating, it applied a nonparametric method applying the smoothness and weight. In addition, the Bayesian method of using the pre-distribution of fertility rates in advanced countries with reference to the three-stage transition phenomenon have been applied. This paper examines which method is reasonable in terms of precision and feasibility by applying estimation, forecasting, and comparing the results of the recent variability of the Korean fertility rate with parametric, non-parametric and Bayesian methods. The results of the analysis showed that the total fertility rate was in the order of KOSTAT's total fertility rate, Bayesian, parametric and non-parametric method outcomes. Given the level of TFR 1.05 in 2017, the predicted total fertility rate derived from the parametric and nonparametric models is most reasonable. In addition, if a fertility rate data is highly complete and a quality is good, the parametric model approach is superior to other methods in terms of parameter estimation, calculation efficiency and goodness-of-fit.

Change of Subalpine Coniferous Forest Area over the Last 20 Years (아고산 침엽수림 분포 면적의 20년간 변화 분석)

  • Kim, Eun-Sook;Lee, Ji-Sun;Park, Go-Eun;Lim, Jong-Hwan
    • Journal of Korean Society of Forest Science
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    • v.108 no.1
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    • pp.10-20
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    • 2019
  • The purpose of this study is to identify the long-term area changes in the subalpine coniferous forests in Korea in order to understand the changes in the subalpine forest ecosystems vulnerable to climate change. We analyzed 20 years of time-series Landsat satellite images (mid 1990s, mid 2010s) for change detection of coniferous forests and compared with the long term changes of climate information to identify their relationship in the study area. As a result, the area of coniferous forests in the study region decreased by 25% over 20 years. The regions with largest changes are Seoraksan, Baegunsan-Hambaeksan-Jangsan, Jirisan, and Hallasan. The region with the largest decrease in area was Baegunsan (reduced area: 542 ha), and the region with large decrease in area and the largest rate of decrease was Hallasan (rate of decrease: 33.3%). As the Jeju region has the most rapid temperature rise, it is projected that Hallasan is the most vulnerable forest ecosystem affected by climate change. The result of this study shows that from a long-term perspective the overall coniferous forests in the subalpine region are declining, but the trend varies in each region. This national and long-term information on the change of coniferous forests in the subalpine region can be utilized as baseline data for the detailed survey of endangered subalpine coniferous trees in the future.

Effect of LED Irradiation on Growth Characteristids of Ginseng Cultivated in Plastic Film House

  • Seo, Sang Young;Cho, Jong hyeon;Kim, Chang Su;Kim, Hyo Jin;Kim, Dong Won;An, Min Sil;Yoon, Du Hyeon
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.10a
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    • pp.45-45
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    • 2019
  • This experiment was carried out using artificial clay and LED in the plastic film house (irradiation time: 08:00~18:00/day). Seedlings (n = 63 per $3.3m^2$) of ginseng was planted on May 17, 2018. LED was combined with red and blue light in a 3:1 ratio and irradiated with different light intensity. The average air temperature from April to September was $12.3^{\circ}C$ $-26.0^{\circ}C$ and it was the the highest at $26.0^{\circ}C$ in August. The test area where fluorescent lamp was irradiated tended to be somewhat higher than the LED irradiation area. The chemical properties of the test soil are as follows. pH levels was 5.3~5.5, EC levels 0.45~0.52 dS/m and OM levels 33~37%. The total nitrogen content was 0.35~0.47% and the available $P_2O_5$ contents was 13.7~16.0 mg/kg, which was lower than the suitable level of 70~200 mg/kg. Exchangeable cations K and Mg contents were within acceptable ranges, but the Ca contents was $28{\sim}38cmol^+/kg$ levels higher than the permissible level ($2{\sim}6cmol^+/kg$). Germination of ginseng leaves took 8~9 days and the overall germination rate was 70~75%. The photometric characteristics of LED light intensity are as follows. The greater the light intensity, the higher the PAR (Photosynthetic Action Radiation) value, illuminance and solar irradiation. Photosynthetic rate was also increased with higher light intensity was investigated at $1.7{\sim}3.2{\mu}mol\;CO_2/m^2/s$. Leaf temperature ($23.7{\sim}24.8^{\circ}C$) by light intensity was the same trend. The growth of aerial parts (plant height etc.) were generally excellent when irradiated with 3 times the light intensity, the growth of the ginseng aerial parts were excellent as follows. The plant height was 42.6 cm, stem length was 25.2 cm, leaf length was 9.6 cm and stem diameter was 5.0 mm. The growth of underground part (root length etc.) was the same, and the root length was 24.4 cm, the tap root length was 6.0 cm, diameter of taproot was 18.2 mm and the fresh root weight was 17.2 g. There were no disease incidence such as Alternaria blight, Gray mold and Anthracnose. Disease of Damping off occurred 2.2~3.6% and incidence ratio of rusty root ginseng was 14.6~20.7%. Leaf discoloration rate was 13.7~48.9% and increased with increasing light intensity. Ginsenoside content of ginseng by light intensity is under analysis.

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A Study on the Research Topics and Trends in South Korea: Focusing on Particulate Matter (토픽모델링을 이용한 국내 미세먼지 연구 분류 및 연구동향 분석)

  • Park, Hyemin;Kim, Taeyong;Kwon, Daewoong;Heo, Junyong;Lee, Juyeon;Yang, Minjune
    • Korean Journal of Remote Sensing
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    • v.38 no.5_3
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    • pp.873-885
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    • 2022
  • The particulate matter (PM) has emerged as a hot topic around the world as it has been reported that PM is related to an increase in mortality and prevalence rates. In South Korea, the importance of PM has been recognized since the late 1990s, and various studies on PM have been conducted. This study investigated the PM research topics and trends for papers (D=2,764) published in Research Information Sharing Service (RISS) using topic modeling based on Latent Dirichlet Allocation (LDA). As a result, a total of 10 topics were identified in the whole papers, and the PM research topics were classified as 'PM reduction (Topic 1)', 'Government policy and management (Topic 2)', 'Characteristics of PM (Topic 3)', 'PM model (Topic 4)', 'Environmental education (Topic 5)', 'Bio (Topic 6)', 'Traffic (Topic 7)', 'Asian dust (Topic 8)', 'Indoor PM (Topic 9)', 'Human risk (Topic 10)'. In particular, the proportion of papers on topics 'Government policy and management (Topic 2)', 'PM model (Topic 4)', 'Environmental education (Topic 5)', and 'Bio (Topic 6)' to the toal number of papers increased over time (linear slope > 0). The results of this study provide the new literature review methodology related to particulate matter and the history and insight.

Comparison of the National Park Ecosystem Health Assessment and an Advanced Assessment System (국립공원 생태계 건강성 평가 시스템 개선 연구)

  • Myeong, Hyeon Ho;Kim, Jeong Eun;Kim, Hye Ri;Oh, Jang Geun
    • Ecology and Resilient Infrastructure
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    • v.8 no.2
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    • pp.112-119
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    • 2021
  • In 2012, the National Park Service conducted an ecological health assessment to efficiently preserve and manage the ecosystem. The need for improving pre-existing management indicators was recognized from the revised Natural Park Act because, while the indicators of the existing evaluation system focused on endangered species, ecosystem disturbance, diversity, water quality (BOD, DO), and habitat fragmentation, they did not reflect the lack of indicators for marine ecological assessment, policy changes, and the time demands. The evaluation results comprised a five-point grading system, which made the analysis of immediate changes, difficult. Therefore, the benthic pollution index (BPI) and habitat restoration indicators were added to improve the evaluation system. The National Park was assessed using 10 classifications, however, only four classifications were evaluated. The ratings were divided into five states, and ten classes were presented as pictograms. The assessment results showed a similar trend as the indicators were improved, increasing from level 3 to level 5. However, the results of the Wolaksan National Park after improvement in the indicators were lower than that before the improvement, whereas, for the Juwangsan National Park, it was higher. This study aims at contributing to the scientific and systematic management of the national park ecosystem by improving the ecological health assessment system.