• Korean Journal of Ecology and Environment
• /
• v.51 no.1
• /
• pp.124-134
• /
• 2018

We analyzed research topics, temporal distribution of field sites, and researcher network of 1,508 limnology publications in the Korean Journal of Limnology (1968~2012) and the Korean Journal of Ecology and Environment (2013~2017). We found that water quality and sediment, phytoplankton, invertebrates, and fish were major subjects during the study periods. Survey of flora and fauna and physiological experiment of freshwater species were the largest subjects during 1970~80s, while other subjects including production, behavior, modeling, and ecological assessment have been rapidly increased since the 1990s. Most of the biological taxa equally studied lotic and lentic system, however, invertebrates and fish related studies more focused on the lotic system. Spatially, the field site of Korean limnology studies was found to be concentrated in main river channels runs through urban areas and artificial lakes than preserved natural areas. Freshwater system, located at the elevation range of 301~400 m (upstream of main channels), had the lowest number of field sites. Collaboration among researchers and different institution types have been steadily increased and expanded as the number of publications increased.

• Journal of Food Hygiene and Safety
• /
• v.24 no.1
• /
• pp.86-93
• /
• 2009

This study was conducted to determine microbiological assessment on edible ices, which is one of mandatory items for HACCP application, and to provide basic scientific data for the improvement of HACCP system. In HACCP applied edible ice companies, the contamination levels of total counts, yeast and mold, and coliform from raw materials, mixed samples before sterilization, mixed samples after sterilization, and final products of edible ices were lower than those of non-HACCP applied edible ice companies. Foodborne pathogens, such as L. monocytogenes, Salmonella spp., B. cereus, B. aureus, Y. enterocolitica were not detected in all samples of edible ices from HACCP applied edible ice companies, but S. aureus was isolated1 from 1 raw material, 1 mixed samples before sterilization and 1 final product of edible ices from non-HACCP applied edible ice companies, respectively.

• Journal of Wetlands Research
• /
• v.18 no.3
• /
• pp.313-323
• /
• 2016

Water temperature affects physical and biological processes in ecologies on river system and is important conditions for growth rate and spawning of fish species. The objective of this study is to compare models for water temperature during the summer season for the Fourchue River (St-Alexandre-de-Kamouraska, Quebec, Canada). For this, three different models, which are CEQUEAU, Auto-regressive Moving Average with eXogenous input and Nonlinear Autoregressive with eXogenous input, were applied and compared. Also, future water temperature in the Fourchue river were simulated and analyzed its result based on the CMIP5 climate models, RCP 2.6, 4.5, 8.5 climate change scenarios. As the result of the study, the water temperature in the Fourchue river are actually changed and median water temperature will increase $0.2{\sim}0.7^{\circ}C$ in June and could decrease by $0.2{\sim}1.1^{\circ}C$ in September. Also, the UILT ($24.9^{\circ}C$) for brook trout are also likely to occurred for several days.

• Journal of Korea Water Resources Association
• /
• v.49 no.2
• /
• pp.155-164
• /
• 2016

Algal blooms not only destroy fish habitats but also diminish biological diversity of ecosystem which results into water quality deterioration of 4 major rivers in South Korea. The relationship between algal bloom and environmental factors had been analyzed through the cross-correlation function between concentration of chlorophyll a and other environmental factors. However, time series of cross-correlations can be affected by the stochastic structure such auto-correlated feature of other controllers. In order to remove external effect in the correlation analysis, the pre-whitening procedure was implemented into the cross correlation analysis. The modeling process is consisted of a series of procedure (e.g., model identification, parameter estimation, and diagnostic checking of selected models). This study provides the exclusive correlation relationship between algae concentration and other environmental factors. The difference between the conventional correlation using raw data and that of pre-whitened series was discussed. The process implemented in this paper is useful not only to identify exclusive environmental variables to model Chl-a concentration but also in further extensive application to configure causality in the environment.

• Journal of Food Hygiene and Safety
• /
• v.27 no.1
• /
• pp.24-29
• /
• 2012

A total of 187 samples of leafy vegetables and fruits were acquired at traditional markets and department stores in Seoul, Korea. Samples were tested for microorganism distributions and for the presence of pathogenic bacteria. The aerobic mesophilic counts ranged between 2.5 and 9.4 log CFU/g, with the highest count recorded from the dropwort. Counts of psychrotrophic microorganisms were as high as those of the mesophilic microorganisms. Total coliform populations between 1.0 and 7.8 log CFU/g were found in 90.9% of the samples. Microbiological counts for fruits were very low. $Escherichia$ $coli$ was isolated in 24 (12.8%) samples. $Staphylococcus$ $aureus$ and $Clostridium$ $perfringens$ contamination were found in 15 (8.0%) and 20 (10.7%) samples. $Salmonella$ species and $Listeria$ $monocytogenes$ were detected in 2.7 and 0.5% of samples, respectively. Among the total 187 samples, 8 samples were contaminated by more than two pathogens. $E.$ $coli$ O157:H7 was not detected in any of the samples. The microbial contamination levels determined in the present study may be used as the primary data to execute microbial risk assessment of fresh vegetables and fruits.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.12 no.4
• /
• pp.264-276
• /
• 2010

The objectives of this study were to introduce the methods of soil respiration measurement, to review soil respiration studies conducted in Korea, and to suggest potential issues generated from using various methods for soil respiration measurement. According to the measurement principles, the methods of soil respiration measurements are classified as: alkali absorption method (AA), closed chamber method (CC), closed dynamic chamber method (CDC), and open flow method (OF). Based on the litereaure review on soil respiration studies in Korea, the CDC method was mostly used by the researchers (62%), followed by the AA (17%), OF (13%) and CC (8%) methods. Along with these methods, various instruments were used such as LI-6400-09, EGM-3, EGM-4, and automatic soil respiration chamber. Most of the soil respiration measurements were carried out in forest ecosystems and the reported soil respiration showed a wide range of variations from 130 to 900 mg $CO_2\;m^{-2}h^{-1}$. Continuous monitoring of soil respiration with minimal disturbance and the potential inconsistency in measurements are still the challenges facing the researchers, causing a paucity in quality datasets of sufficient quantity. Few attempts of intercomparison among different methods hinder the data users from synthetic analysis and assessment of the collected datasets. In order to better estimate soil carbon budget and understand their exchange mechanisms in key ecosystems of Korea, it is necessary to measure soil respiration at various plant functional types, soils, and climate conditions over a decadal time scale along with the study on the partitioning of soil respiration into autotrophic and heteorotrophic components.

• Korean Journal of Childcare and Education
• /
• v.7 no.2
• /
• pp.181-203
• /
• 2011

The purposes of this study were to examine the perception of directors and child care providers regarding the Seoul-type Child Care Accreditation and its operating system. The objects were 309 directors and child care providers at accredited Seoul-type child care centers. The collected data was analyzed using frequency, percentiles, and ${\chi}^2$. The results are as follows: First, the majority of directors and child care providers perceived 'the preparation for effective quality control of child-care service' as the primary purpose of the Seoul-type Child Care Accreditation. Many of them responded that the child care centers meeting the purpose of accreditation would be 'private' and 'home-based' ones. Seoul-type Child Care Accreditation was easier to pass compared to National Child Care Accreditation. The directors and child care providers perceived that the accreditation will narrow the gap between public and private child care centers. Second, in operating customized child-care service, most directors preferred 'submits only the same plan as that of a designated one', but most child care providers preferred 'assessment after providing customized child-care'. For the reliable child-care service and accounting management system, both subject groups showed general satisfaction with 'current system'. Third, both subject groups responded that 'overtime pay for child care providers' and 'government's consistent child-care policy' were what they desire most to improve Seoul-type Child Care Accreditation.

• Journal of Convergence for Information Technology
• /
• v.10 no.3
• /
• pp.115-125
• /
• 2020

Problem-Based Learning is the most commonly used teaching method in the field of education as the demand for talented people with creative problem-solving abilities has increased in recent society. In this study, we developed a tool that can simply and regularly measure the learning effects of applying Problem-Based Learning on the classroom. Twenty-two preliminary items for the development were constructed by gathering expert opinions about items collected in existing research of Problem-Based Learning effects measurement. Using this preliminary items, data were collected from 124 students who took the subject-based study. And the validity and reliability were verified through Rash analysis. 11 of 124 students and 1 of 22 items were found to nonconforming and excluded. In addition, the optimal scale for the configuration of this tool was found to be a four-point scale, and the reliability of separation on the subject and the item was found to be excellent. We hope that the assessment tools of Problem-Based Learning effectiveness developed in this study will be actively used to measure learning effectiveness and manage the quality of education.

• Journal of the Korea Institute of Building Construction
• /
• v.15 no.4
• /
• pp.425-431
• /
• 2015

Since the construction of Kori 1 was completed in 1978, the construction projects for nuclear power plant are increasingly expanded into domestic and foreign sites. However, some of construction sites of nuclear power plant have the problems of process delay and cost loss due to lack of ability of risk management. The construction of reactor containment building in nuclear power plant is especially dotted with many risk factors because it needs professional skills and large-scale resources due to long duration compared with different construction phase. Therefore, it needs the study that analyzes risk factors expected in construction of reactor containment building and suggests way of stable performance of projects. So, this study assesses risk factors of construction of reactor containment building. For the objectives, this study uses survey for group of minority specialists of 36 experts. The risks of 24 factors is classified by criterions of process, cost, safety, and quality and the results of assessment is analyzed by analytic hierarchy process. As the results, the importance and priority of risk factors classified by each criterion were calculated and the applicability of analytic hierarchy process was identified to analyze risk factors of nuclear power plant construction. These will be baseline data for risk management in construction phase of reactor containment building.

• Korean Journal of Environmental Biology
• /
• v.31 no.4
• /
• pp.419-428
• /
• 2013

The objectives of this research were to determine ecological characteristics and chemical gradients in two different loach populations-Misgurnus anguillicaudatus ($M_a$) and Koreocobitis rotundicaudata ($K_r$). Eight chemical parameters were compared to test the chemical preferences between the two species. The population of Kr occurred more in better water quality, compared to the $M_a$-population. The $M_a$-population co-occurred more with tolerant species (TS) and omnivores, whereas the $K_r$-population co-occurred more with sensitive species (SS) and insectivores. The differences in the tolerance and trophic composition matched well with the result of stream health assessment, based on the multi-metric model of Index of Biological Integrity (IBI). The IBI value in habitat with the $M_a$-population was "19.6" (range: 8~40) indicating a fair condition, and the IBI values of $K_r$-population was 29.4 (range: 12~40) indicating good condition. Similar results were found in physical habitat health analysis (QHEI). Overall, data analysis showed that the $M_a$-population belong to the tolerant species and $K_r$-population belong to sensitive species in the tolerance classification.