• Korean Journal of Ecology and Environment
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• v.49 no.3
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• pp.228-235
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• 2016

Aquatic ecosystems are receiving various harmful effects due to anthropogenic chemical pollutions. To protect wildlife, risk assessments of the chemicals are conducted using reference indexes of toxicity estimated by species-level laboratory tests and/or micro-/mesocosm community-level studies. However, the existing micro-/mesocosm communities are structurally too complicated, and it is also difficult to compare the experimental results directly with those from species-level tests. Here, we developed a procedure of a simple bi-trophic microcosm experiment which contains the common species (a green algae, Pseudokirchneriella subcapitata and a cladoceran, Daphnia magna) for testing chemical toxicities. For the proper operation of bitrophic microcosm experiment, the minimum required concentration of primary producer (P. subcapitata) is $5{\times}10^5cells\;mL^{-1}$. The microcosm system showed higher stability when the initially introduced D. magna population was composed of neonates (<24-h old) than adults and those mixture. This simple microcosm system would be an applicable tool to estimate the disturbing impacts of pollutants on plant-herbivore interactions, and linking the species- and population-/community level risk assessments in the future studies.

• Korean Journal of Ecology and Environment
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• v.53 no.2
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• pp.173-184
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• 2020

Irrigation ponds, 'dumbeong', which are artificially constructed water resources for traditional farming, serve as a biological shelter connecting seasonally created rice paddy fields to local freshwater ecosystems. This 2018 study surveyed 143 irrigation ponds in the western Civilian Control Zone (CCZ) area from August to September, revealing species diversity and community characteristics of benthic macroinvertebrates. A total of 13,454 individuals of macroinvertebrates were captured and classified into 3 phyla, 5 classes, 17 orders, 59 families, 192 species. Among Insecta, the most frequently recorded order was Odonata, 55 spp.(33.7%), followed by Coleoptera, 52 spp. (31.9%), Hemiptera, 34 spp. (20.8%), Diptera, 17 spp. (9.8%), Ephemeroptera, 3 spp. (2.4%), Trichoptera, 1 spp. (0.6%) and Lepidoptera, 1 spp. (0.6%). Taxon of non-Insecta consisted of Mollusca, 14 spp. (48.2%), Annelida, 11 spp. (37.9%) and Arthropoda, 4 spp. (3.4%). The analysis of Diversity Index (H'), Species Richness Index (RI), Dominance Index (DI) and Evenness Index (J') revealed the general stability of communities in the study sites. A total of 28 rare species were found in 98 study sites, including three endangered species designated by the Ministry of Environment. These results showed that the species diversity and rarity of macroinvertebrates in the study area were greater than those of previous research on lentic wetlands (lake, etc.) and national conserved wetlands(Upo-swamp, etc.) in Korea. A conservation planning of aquatic ecosystems in the western CCZ area, therefore, should focus on conservation of irrigation ponds.

• Korean Journal of Community Nutrition
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• v.7 no.6
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• pp.833-843
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• 2002

This study was carried out to investigate the effect of hygiene education on the microbiological changes of processing utensils and the environmental in the manufacture of cereals and to evaluate the Cd, Pb contents and nutrient compositions of 11 cereals. The result of microbiological evaluation was that fungi, coliforms and staphylococcus species were detected in employees, on equipment, utensils and environments in the first inspection. Fungi were detected in most of the cereals, staphylococcus species were detected in soybeans, perilla seeds and sea tangle How, and bacillus cereus was detected in sorghum and black sesame seeds. The water content of rice, barley, glutinous rice, brown rice and carrot flour in packaged products, and in carrot flour, angelica keiskei, carrot, sea mustard and potato in bulk products was in excess of 8.0%. The Pb content of cereals was 0.14-0.51 mg/kg and Cd was not found. The acid value of Job s tears flour and black sesame seed flour was higher than 5.0 mg/g oil. Cereals were manufactured from 41 different cereals and grains, legumes, seeds and nuts, vegetables, potatoes, seaweeds, fruits, glucose and salt. The average content of cereals and grains, legumes, and seeds and nuts in cereals was 75.75%, 16.19% and 4.93%, respectively. The mean nutrient content per 100 g of cereals was calories 365.8kcal, protein 13.3 g, fats 5.9 g, carbohydrates 63.4 g, Ca 91.8 mg, p 269.9 mg, Fe 3.15 mg, Na 76.2 g, K 421.8 mg, Zn 2.33 mg, Vit. A 12.5 R.E., Vit. B$_1$0.23 mg, Vit. $B_2$ 0.16 mg, Vit. $B_6$ 0.46 mg, Niacin 3.5 mg, Vit. C 1.36 mg, folic acid 62.3 $\mu$g and Vit. E 1.24 mg. When nutrients value of 48 g of cereals and 200 $m\ell$l of milk was compared to 1/3 of the RDA, the values were below than 60% of 1/3 of the RDA except Na, K, Vitamin $B_1$ and C contents. The average carbohydrate : protein : fat ratio of energy intake was 54.27 : 17.45 : 28.28, respectively. Therefore, a training program consisting of the education of the staff in surveillance and standard operating procedures, the elimination of dangerous procedures, sanitation checklist, the implementation of Preparation methods and standard recipes for cereals is required.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.3
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• pp.262-271
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• 2000

This study was carried out to clarify the spatial and temporal patterns of benthic environments and macrobenthos on the subtidal soft-bottom in Chonsu Bay. Seasonal surface water temperature was similar to the bottom layer, but freshwater discharges into the outlets dereased the surface salinity around the dyke in summer. Bottom dissolved oxygen was decreased deeply around the dyke and created the de-oxygenated layer during summer. Sediment grain size was consisted of finer at the neighboring of the dyke than the mouth of the bay. Organic matters including the sediment were decreased at the mouth of the bay. A total of 311 species ($769\;ind./m^2$) were identified. Polychaetes were the most abundant faunal group in the number of species and densities. The number of species revealed the spatial patterns that it was higher in the mouth of the bay, and their densities showed seasonal changes by mass recruitment occurred at the most of the area in summer, At this time, opportunistic species, Lumbrineris iongifolia and Theora fragilis, were also recruited massively. Chonsu Bay were classified into five station groups by the cluster analysis. The dominant species around the dyke were composed to opportunistic species, those in middle area were Sternaspis scutata, Paraplionospio pinnata, and those in the mouth of the bay were Mediomastus californiensis, Nephtys polybranchia. Seasonal fluctuations and spatial difference of environments seem to have influenced to the species compositions and affected to the stability of benthic ecosystems spatial-temporally In Chonsu nay.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.599-604
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• 2015

This study was conducted the vegetation clustering analysis for the 3 mountains of Mt. Bulam, Mt. Daemo, Mt. Bonghwa which were the urban forests of Seoul. Based on the results of the analysis related to the vegetation clustering, it was found that the clustering of Mt. Bulam consisted of pine trees(Pinus densiflora)-Mongolian oak(Quercus mongolica), Hornb eam(Carpinus laxiflora)-Pitch pine(P. rigida), oriental oak(Q. variabilis) - a wild pear tree(Sorbus alnifolia) while the clustering of Mt. Daemo consisted of Pitch pine-Japanese larch(Larix leptolepis), Poplar(Populus tomentig landulosa)- black birch(Betula davurica pall). Meanwhile, the clustering of Mt. Bonghwa consisted of pine trees-a wild pear tree Community and Sawtooth oak(Q. acutissima)-Cherry Blossoms(Prunus serrulata). In relation to the similarity index by region in Mt. Bulam, Mt. Daemo, and Mt. Bonghwa, the similarity index of Mt. Bulam and Mt. Daemo stood at as high as 0.634, suggesting the distribution of similar vegetation, and the dominance index of the Mt. Daemo region was found to be 0.166 which suggests the dominance of many species compared to other regions. In addition, the results of species diversity showed that Mt. Daemo had the highest stability, and the species diversity, maximum species diversity, evenness indices were highest in Mt. Bulam, followed by Mt. Bonghwa and Mt. Daemo. The dominance index was the lowest in Mt. Bulam, followed by Mt. Bonghwa and Mt. Daemo.

• Korean Journal of Social Welfare
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• v.57 no.4
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• pp.225-251
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• 2005

This study examines the changing paradigm of family welfare policy and tries to find an appropriate model for the delivery system of family welfare service. First, the study reviews the contexts of family policy in new paradigm, and traces the changing process of family welfare-related administration from the ministry of human and health to the ministry of family and gender equality. Second, the study examines the principles of the delivery system for family welfare service to pursue the advancement of family policy. In conclusion, it proposes an alternative model for the successful settlement into community of family welfare delivery system, and a desirable position and role of family support center. The principles of the delivery system of family welfare service is fundamentally to make family policy come realistic, such as strengthening family stability through the harmonic reconciliation of work and family, preventing any forms of families from social safety net, and securing happy lives. Comprehensiveness, continuity, effectiveness, and accessibility of the system are also needed. In particular, family support center, recently very controversial, could be better as a representative council of networking various kinds of community organizations in the fields of family welfare enhancement, rather than organization of direct service provision, such as family counselling, education and therapy. Finally, an alternative model of delivery system for family welfare service is presented.

• Korean Journal of Community Nutrition
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• v.29 no.2
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• pp.129-143
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• 2024

Objectives: The objective of this study is to compare a nutritionally balanced soft blend diet (SBD) with a soft fluid diet (SFD) on the health of inpatients who have undergone oral and maxillofacial (OMF) surgery, ultimately aiming to enhance care outcomes, improve health-related quality of life (QOL), and increase satisfaction with the hospital. Methods: Thirty-two patients were randomized into two groups: sixteen received SFD and sixteen received SBD. Anthropometric, laboratory evaluations were conducted upon admission and discharge. Patients filled out questionnaires on demographics, diet satisfaction, food intake amount, and health-related QOL on the day of discharge, assessed using the EuroQoL 5 Dimensions 3 Level and EuroQoL Visual Analogue Scale (EQ-VAS) instruments. Data were analyzed with descriptive statistics, χ² tests for group differences, and paired nonparametric t-tests for within-group comparisons. The Mann-Whitney U test evaluated inter-group differences in preoperative weight and body mass index (BMI), postoperative changes, meal satisfaction, intake, health-related QOL, and self-assessed health status. P-values were set at a significance level of 0.05. Results: The SBD group had higher dietary intake (63.2% vs. 51.0%) and greater diet satisfaction (80.6 vs. 48.1, P < 0.0001) compared to SFD group. Health-related QOL, measured by EQ-VAS, was better in SBD group (70.3 vs. 58.8, P < 0.05). Postoperative weight and BMI decreased in SFD group but increased in SBD group (P < 0.01). Changes in laboratory results showed more stability in the SBD group. No postoperative infections were reported in SBD group, whereas SFD group had a 31.25% complication rate. Conclusions: While SFD is often recommended after OMF surgery to protect oral wound healing process, our study reveals that SBD not only enhances physical and psychological outcomes but also, somewhat unexpectedly, supports wound healing and reduces complications. Essentially, SBD promotes physical recovery and enhances health-related QOL than SFD by supporting both somatic and mental healing aspects.

• Journal of The Korean Society of Grassland and Forage Science
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• v.44 no.2
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• pp.113-117
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• 2024

This study was conducted to find a way to improve quality by observing changes in quality and microbial communities according to whether corn silage was treated with additives and the storage period, and to utilize them as basic research results. The experimental design was performed by 2×4 factor desigh, and the untreated (CON), and the additive inoculated (ADD) silage were stored and fermented for 30 (TH), 60 (ST), 90 (NT), and 120 (OHT) days, with each condition repeated 3 times. There was no change in the nutrient content of corn silage according to additive treatment and storage period (p>0.05). However, the change in DM and the increase in the relative proportions of lactic acid content and Lactobacillales according to the storage period (p<0.05) indicate that continuous fermentation progressed until OHT days of fermentation. Enterobacterales (33.0%), Flavobacteriales (14.4%), Sphingobacteriales (12.7%), Burkholderiales (9.28%) and Pseudomonadales (6.18%) dominated before fermentation of corn silage, but after fermentation, the diversity of microorganisms decreased sharply due to the dominance of Lactobacillales (69.4%) and Bacillales (11.5%), Eubacteriales (7.59%). Therefore, silage maintained good fermentation quality with or without microbial additives throughout all fermentation periods, but considering the persistence of fermentation even in long-term storage and the aerobic stability, it would be advantageous to use microbial additives.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.115-116
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• 2012

The demand for flexible electronic systems such as wearable computers, E-paper, and flexible displays has increased due to their advantages of excellent portability, conformal contact with curved surfaces, light weight, and human friendly interfaces over present rigid electronic systems. This seminar introduces three recent progresses that can extend the application of high performance flexible inorganic electronics. The first part of this seminar will introduce a RRAM with a one transistor-one memristor (1T-1M) arrays on flexible substrates. Flexible memory is an essential part of electronics for data processing, storage, and radio frequency (RF) communication and thus a key element to realize such flexible electronic systems. Although several emerging memory technologies, including resistive switching memory, have been proposed, the cell-to-cell interference issue has to be overcome for flexible and high performance nonvolatile memory applications. The cell-to-cell interference between neighbouring memory cells occurs due to leakage current paths through adjacent low resistance state cells and induces not only unnecessary power consumption but also a misreading problem, a fatal obstacle in memory operation. To fabricate a fully functional flexible memory and prevent these unwanted effects, we integrated high performance flexible single crystal silicon transistors with an amorphous titanium oxide (a-TiO2) based memristor to control the logic state of memory. The $8{\times}8$ NOR type 1T-1M RRAM demonstrated the first random access memory operation on flexible substrates by controlling each memory unit cell independently. The second part of the seminar will discuss the flexible GaN LED on LCP substrates for implantable biosensor. Inorganic III-V light emitting diodes (LEDs) have superior characteristics, such as long-term stability, high efficiency, and strong brightness compared to conventional incandescent lamps and OLED. However, due to the brittle property of bulk inorganic semiconductor materials, III-V LED limits its applications in the field of high performance flexible electronics. This seminar introduces the first flexible and implantable GaN LED on plastic substrates that is transferred from bulk GaN on Si substrates. The superb properties of the flexible GaN thin film in terms of its wide band gap and high efficiency enable the dramatic extension of not only consumer electronic applications but also the biosensing scale. The flexible white LEDs are demonstrated for the feasibility of using a white light source for future flexible BLU devices. Finally a water-resist and a biocompatible PTFE-coated flexible LED biosensor can detect PSA at a detection limit of 1 ng/mL. These results show that the nitride-based flexible LED can be used as the future flexible display technology and a type of implantable LED biosensor for a therapy tool. The final part of this seminar will introduce a highly efficient and printable BaTiO3 thin film nanogenerator on plastic substrates. Energy harvesting technologies converting external biomechanical energy sources (such as heart beat, blood flow, muscle stretching and animal movements) into electrical energy is recently a highly demanding issue in the materials science community. Herein, we describe procedure suitable for generating and printing a lead-free microstructured BaTiO3 thin film nanogenerator on plastic substrates to overcome limitations appeared in conventional flexible ferroelectric devices. Flexible BaTiO3 thin film nanogenerator was fabricated and the piezoelectric properties and mechanically stability of ferroelectric devices were characterized. From the results, we demonstrate the highly efficient and stable performance of BaTiO3 thin film nanogenerator.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.3
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• pp.85-107
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• 2011

This study analyzed the influence of supporting policy fund on financial performance of small & medium sized venture firms. The outcomes are as follows. First, it was found that 11 dependent variables in profitability, stability, activity, and growth represent have significantly positive influence on financial performances 4 years after policy fund rather than prior to the fund. In short, supporting policy fund is found to bring improvement on financial performance. Second, it was found that growth rate in asset as a growth indicator and interest coverage ratio as a stability indicator have significantly positive influence on operating income to sales and ROA, respectively. Third, it was found that operating income to sales as a profitability indicator and asset turnover ratio as an activity indicator have positive influence on current ratio. Finally operating income to sales as a profitability indicator and growth rate in sales as a growth indicator have positive influence on interest coverage ratio.