• Title/Summary/Keyword: 4-period development

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Annual Change and C:N:P ratio in Particulate Organic Matter in Chinhae Bay, Korea (한국진해만 입자유기물 함량과 C:N:P 비의 연변화)

  • LEE, PIL-YONG;KANG, CHANG-KEUN;PARK, JONG-SOO;PARK, JOO-SUCK
    • 한국해양학회지
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    • v.29 no.2
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    • pp.107-118
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    • 1994
  • An investigation of the annual change and C:N:P ratio in particulate organic matter (POM) in Chinhae Bay, a semi-enclosed bay of the southern coast of Korean Peninsula, was carried out for a period of 12 months between January and December, 1993. The concentrations of POM have a broad range: 198∼4,416 ugC/l, 24∼792 ugN/l and 4.5∼69.0 ugP/l, Marked seasonal changes of POM, particularly particulate organic carbon (POC) and nitrogen (PON), were observed in the surface water. Generally, the concentration of POM peaks in summer. The C:N:P composition ratio of particulate organic matter, which is high in summer, also shows a seasonal change. The C:N assimilation ratio is constant at 6.53, which is consistent with the Redfield ratio. The significant linear relationship between POM and chlorophyll-a in the surface water during the survey period (except for January and February) and the C:N ratio suggest that the concentration of POM is controlled by phytoplankton biomass. POM peaks in summer, a period characterized by high freshwater input and the strong stratification, as a result of the intense proliferation of phytoplankton by a large amount of nutrient loading from the tributaries. On the other hand, the high C:P and N:P ratios in summer indicate that P is limited for phytoplankton growth owing to N-enrichment from a high input of freshwater with a high dissolved inorganic N:P ratio.

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The Analysis on the KAIE Articles using Social Network Analysis (사회연결망 분석을 활용한 정보교육학회 논문 분석)

  • Park, SunJu
    • Journal of The Korean Association of Information Education
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    • v.20 no.6
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    • pp.543-552
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    • 2016
  • Recently, a number of researches focus on social network analysis and it is applied to various fields not only in social science area but also in natural science area. Therefore, the social network analysis and the text analysis were conducted in order to analyze the current trend of the theses in information education field. The result indicated that the most frequently mentioned words were consistent with the development of information technology and the change in information education curriculum. That is, the mentioned words were computer aided instruction (CAI) and courseware for period 1, ICT for period 2, smart and scratch for period 3, and in period 4, computational thinking ability and coding appeared for the first time. Moreover, as the result of social network analysis, it concluded the research topics became more complicated and detailed as the words diversified throughout the period in which the simplified network in period 1 changed its configuration into a structure with more diversified words of higher centrality.

Groundwater Hydrological Study of Silla Well in Gyeongju (경주 신라우물의 지하수 수문학적 연구)

  • Bae, Sang Keun
    • Journal of Environmental Science International
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    • v.25 no.1
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    • pp.99-105
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    • 2016
  • In this paper, a groundwater hydrological study of the Gyeongju well during the Silla period is conducted to investigate how sufficiently the Gyeongju well supplied water demand at the time. It is assumed that the current geology and soil condition in Gyeongju remain similar to the Silla period. Also, the land use and land coverage during the Silla period is estimated based on the current land condition in Gyeongju. Precipitation during the Silla period is analyzed using precipitation data from 1984 to 2014 provided by Gyeonju weather station. Precipitation analysis is applied based on 3 different scenarios; precipitation intensity during the Silla period was Case (1) the same as, Case (2) 30% more, and Case (3) 30% less than the precipitation intensity of the last decade (2005~2014). Furthermore, to observe the use of the well in Gyeongju during droughts, the following condition(Case (4)) is also considered; ten year drought during the Silla period was the same as the ten year drought from 1984 to 2014. Available amount of groundwater development is analyzed using NRCS-CN method. The results show that the potential amount of groundwater in Gyeongju during Silla era was for Case (1) $62,825,272m^3/year$, Case (2) $93,606,567m^3/year$, Case (3) $32,277,298m^3/year$, and Case (4)$32,870,896m^3/year$. Also, it has been shown that $45,260,000m^3$ of groundwater were required to supply to all households in Gyeongju during Silla era. Therefore, if the precipitation intensity during Silla era was similar with the last decade, the groundwater would provide enough supply to all households in Gyeongju. However, in the case that the precipitation intensity during Silla era was 30% less than the last decade or a ten year drought happened, it is predicted that the water use in Gyeongju would have been limited.

Rural residential environment: Identifying trends through text network analysis (텍스트 네트워크 분석을 활용한 농촌 주거환경 연구 동향)

  • Lee, Cha Hee
    • Journal of Korean Society of Rural Planning
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    • v.26 no.1
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    • pp.39-49
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    • 2020
  • The study analyzed the frequency of simultaneous occurrence of keywords presented in a total of 805 papers published in domestic journals from 1995 to 2019 by social network analysis(SNS) method, and examined core keywords of each period(5 years), in order to understand the research trends of the rural residential environment. The main results are as follows. First, as a result of the analysis of centrality, 'Community', 'Tourism' and 'Comprehensive Rural Village Development Project' were the top 3 keywords. Second, examined by each period, the top keywords are 'Eco Friendly' in 2000~2004, 'Tourism' in 2005~2009 and 2010~2014, 'Community' in 2015~2019. Third, comparing the structural characteristics of core keywords 2nd, 3rd, and 4th period, a network centering on 'Tourism' was clearly formed in the 2nd period. 'Tourism' was divided into 'Community' and a movement to form a separate group appeared in the 3rd period. In the 4th period, 'Community' was found to form a network without direct connection with 'Tourism'. The results of this study suggest the trend change of viewpoint for the rural area in the domestic research on rural residential environment. It has been confirmed that while the research had been carried out with the viewpoint of rural area as a 'tourist attraction' or 'sightseeing spot' for the urban citizens until the mid-2010s, in the research of late 2010s the viewpoint has settled down as a 'residential space' or 'space for new economic activities' of a variety of rural residents.

An Analysis on the Rural Research Trends using Topic Modeling (토픽모델링을 활용한 농촌연구 동향분석)

  • Kim, Gaeun;Jeong, yookyung;Lim, Yeonghun
    • Journal of Korean Society of Rural Planning
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    • v.29 no.4
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    • pp.81-92
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    • 2023
  • The purpose of this study is to identify rural research topics, differences in research topics over time, and key mediators through the analysis of academic research trends using topic modeling. This study analyzed a total of 1,183 articles published in the Journal of Rural Planning and Rural Society over a 23-year period (2000-2022). We categorized rural research topics into 30, examined the proportion of research in each topic, and identified major changes in research topics over time. We also identified key words that mediate between research topics. The study found that, first, rural research trends can be categorized into five types (resources and utilization, area/space, people, ecosystem/environment, and tourism), with area/space being the most studied. Subtopics include rural amenities, rural disappearance/village miniaturization, and rural landscape management. Second, the research topics for each period were different. In the first period(2003-2007), the main research topics were rural amenities and Agricultural production- based climate vulnerability assessment. In the second period(2008-2012), the main research topics were Rural extinction and village depopulation, and rural landscape management, and in the third period(2013-2017), the main research topics were rural sixth industrialization and rural ecotourism. In the fourth period(2018-2022), rural development planning and rural life services(life SOC) were the main research topics. The significance of this study is that it extends the existing method of analyzing research trends and provides basic data to enhance comprehensive insights and understanding of rural research.

Studies on the Preservation of Apple -Effect of Inorganic Compounds Applied in the Field on the Shelf-life of Apples- (사과 저장(貯藏)에 관한 연구(硏究) -무기영양(無機營養)이 사과의 저장(貯藏)에 미치는 영향-)

  • Park, Nou-Poung;Kim, Yun-Jin;Kim, Sung-Kih;Rhee, Chong-Ouk
    • Korean Journal of Food Science and Technology
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    • v.9 no.1
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    • pp.13-18
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    • 1977
  • In order to improve the storage ability of Spur Red Delicious apple, calcium ingredients were applied to the apple tree during the growing period, and then the effects of calcium on appearances and respiratory activity of harvest apples were investigated during the storage period. The results of this work were summarized as follows: 1. The freshness of apples treated by calcium compounds reached $73{\sim}78%$, but that of control group was 68% by March of next year. 2. The respiratory rate of the apples that had been applied the high concentration of ammonium sulfate in field during the growing period, was accelerated rather than control group, and that of calcium treatment groups was continuously inhibited during the storage period. 3. The direct foliar application of calcium compounds in the field was more effective than dipping apples in calcium chloride solution for better quality and improving storage ability after harvest. 4. The freshness and hardness relatively not much decreased in calcium treatment groups even after 5 month storage.

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The effect of aluminum coating to corrugated packaging on quality characteristics of Enoki mushrooms (Flammulina velutipes) during storage (골판지 포장지의 알루미늄 코팅이 팽이버섯의 저온저장 중 품질 특성에 미치는 영향 )

  • Ah-Na Kim;Kyo-Yeon Lee;Chae-Eun Park;Se Ri Kim;Song Yi Choi;Injun Hwang;Kyung Min Park;Sung-Gil Choi
    • Food Science and Preservation
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    • v.31 no.4
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    • pp.612-622
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    • 2024
  • We examined the physicochemical properties and microbial safety of Enoki mushrooms during storage at 5℃ for 9 weeks, with different packaging containers that are corrugated, Al-coated, and without packaging (control). The weight change of Enoki mushrooms in the different containers due to moisture loss was 1.9%, 0.9%, 0.6% for control, corrugated, and Al-coated packaging, respectively. The degree of browning rapidly increased as the storage period increased in the control sample. However, corrugated and Al-coated packaging suppressed the browning degree. The changes of color L-, a-, and b-vlaues were minimal changes in Al-coated packaging. There was no significant difference in the total amino acids, polyphenol oxidase, and peroxidase in corrugated packaging and Al-coated packaging, regardless of the storage period. The microbial growth such as total aerobic bacteria, yeast, and mold of Enoki mushroom during the storage period, were significantly suppressed in Al-coated packaging samples as compared to the control and corrugated packaging. In conclusion, Al-coated packaging has beneficial effects such as preventing moisture loss, maintaining browning degree, inhibiting oxidative enzyme reaction, and ensuring microbial safety of Enoki mushrooms during the storage period. Al-coated packaging is considered effective for extending the shelf-life and improving the storage and distribution of mushrooms.

Microbial Colonization at Early Life Promotes the Development of Diet-Induced CD8αβ Intraepithelial T Cells

  • Jung, Jisun;Surh, Charles D.;Lee, You Jeong
    • Molecules and Cells
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    • v.42 no.4
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    • pp.313-320
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    • 2019
  • Intraepithelial lymphocytes (IELs) develop through the continuous interaction with intestinal antigens such as commensal microbiome and diet. However, their respective roles and mutual interactions in the development of IELs are largely unknown. Here, we showed that dietary antigens regulate the development of the majority of $CD8{\alpha}{\beta}$ IELs in the small intestine and the absence of commensal microbiota particularly during the weaning period, delay the development of IELs. When we tested specific dietary components, such as wheat or combined corn, soybean and yeast, they were dependent on commensal bacteria for the timely development of diet-induced $CD8{\alpha}{\beta}$ IELs. In addition, supplementation of intestinal antigens later in life was inefficient for the full induction of $CD8{\alpha}{\beta}$ IELs. Overall, our findings suggest that early exposure to commensal bacteria is important for the proper development of dietary antigen-dependent immune repertoire in the gut.

A Study on Development Strategy of Industrial Complex using SWOT/AHP Analysis Theory - The Case of the Firms in Seoul Digital Industrial Complex (SWOT/AHP 분석기법을 이용한 산업단지의 발전 전략에 관한 연구: 서울디지털산업단지를 중심으로)

  • Kim, Bo Seok;Lee, Min Jung
    • The Journal of Information Systems
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    • v.24 no.4
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    • pp.61-81
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    • 2015
  • Purpose Seoul Digital Industrial Complex has remarkably grown both quantitatively and qualitatively in short period of time since it started restructuring project in 1997. It's also not few that there were various challenges and difficulties in this industrial complex due to fast growth in short-term, such as the deficient amenities, noncooperation among the related organizations. Now, it's time to overcome these challenges and difficulties to establish new strategy for the sustainable growth and development of this Industrial Complex. Methodology There are some previous researches but almost none of them considered the priority order of the development strategy having reflected the needs of industrial complex in point of customer. In this regard, this study suggests the development strategy of Seoul Digital Industrial Complex by supplementing the limits of proceeding researches and using the combined SWOT/AHP analysis theory. Findings Based on the final analysis result of survey by combined SWOT/AHP method, this study suggests the priority order of 4 development strategies for Seoul Digital Industrial Complex, such as SO strategy, ST strategy, WO strategy and WT strategy.

A Systematic Review of the Literature on Tattoo and Semi-permanent Makeup (문신 및 반영구화장에 관한 체계적 문헌고찰)

  • Soyeon Park;Eunkyung Seo;Sungwook Kang
    • Journal of the Korean Applied Science and Technology
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    • v.40 no.3
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    • pp.435-452
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    • 2023
  • This study was conducted for a systematic literature review according to the period, subject, and research method for 198 papers related to tattoo and semi-permanent makeup published from 1979 to 2022. By period, it was divided into the first period (1979-1994), the second period (1995-2005), the third period (2006-2012), and the fourth period (2013-2022). In the first period, research on health and medical aspects was the main focus, and in the second period, studies in various aspects such as art and culture began to appear. The 3rd period was characterized by increased research on semi-permanent makeup, and the 4th period was marked by a rapid increase in research on tattoos and semi-permanent makeup. By research topic, it was analyzed by dividing it into health and medical care, beauty, fashion and art, society and culture, law and system. As a result, cosmetic studies were most actively conducted to identify consumers' preferences and perceptions, and health and medical studies were the second most common. Recently, as the need for legalization has increased, studies related to laws and systems have increased rapidly, and studies on culture, history, and fashion have also been conducted. By research method, survey research were used the most, and various methods such as literature study and case studies were also used. This study is expected to further promote follow-up research in the future and contribute to the development of related industries.