본 연구는 실시간 온라인으로 진행되는 학부 교양 초급 한국 어 수업에서 강의식 수업과 플립 러닝식 수업을 실시하고 각 수업 방 식에 대한 학습자 인식 및 수업 효율성을 살펴보는 데 목적이 있다. 이를 위해 ZOOM에서 8주간 각 수업 방식을 적용한 한국어 수업을 진행하고 사후 설문 조사를 실시하였다. 그 결과 학습자들은 강의식 수업보다는 플립 러닝식 수업에 긍정적인 반응을 보였으며, 강의식 수 업에서는 ‘어휘 및 문법’ 영역, 플립 러닝식 수업에서는 ‘듣기, 읽기, 쓰 기, 말하기’ 영역의 수업 효율성이 높게 나타났다. 이에 실시간 온라인 으로 진행되는 초급 한국어 수업의 효율을 높이기 위해서는 수업 환 경과 언어 영역의 특성을 고려한 혼합된 수업 방식이 필요할 것이다.

To this day, conflicts have intensified between managers who want to preserve biosphere reserves and citizen who want to develop them. Based on this problem, this study seeks to investigate the establishment of a forum for communication between various stakeholders and to promote the economic development of local communities while preserving biodiversity. First, in terms of conservation, the results indicated that Gyeonggi Province and Namyangju City highly valued direct conservation activities in biosphere reserves, whereas Pocheon and Uijeongbu City highly valued indirect conservation functions through management or monitoring. Second, in terms of development, it was found that there were differences in the roles, perceptions and responsibilities with respect to biosphere reserves among the different layers of government: the central government agency, the Cultural Heritage Administration, the metropolitan government, Gyeonggi-do, and the local governments, Pocheon, Namyangju, and Uijeongbu. Third, in terms of logistical support, which serves as a function for communication and practical participation among management entities, the results suggested that it was necessary to establish a comprehensive decision-making organization for efficient management and operation and to provide opportunities for active participation. The study can be utilized as a basic reference for developing efficient communication by management entities in protected areas with similar challenges.

This study used a batch DAF (dissolved air flotation) jar tester to evaluate the algae removal efficiency of alum and PAC coagulants during coagulation, flocculation, and flotation. Optimal coagulant dosages were 0.06 ~ 0.15 mL/L (12.0 ~ 26.0 mg Al/L,17%), 0.08 ~ 0.20 mL/L (10.0 ~ 24.0 mg Al/L, 12%), 0.25 ~ 0.30 mL/L (25.0 ~ 30.0 mg Al/L, 10%) for PAC, and 3.0 ~ 5.0 mL/L (81.0 ~ 135.0 mg Al/L, 2.7%) for alum. Turbidity of treated water was 1.0 ~ 2.0 NTU in optimal coagulation, flocculation, and flotation conditions for the four coagulants types. The amount of coagulant injected tended to decrease with increasing Al content in the coagulant, as follows : 17% PAC < 12% PAC < 10% PAC < 2.7% alum. Turbidity removal efficiencies were in the order of 12% PAC (93.6%) > 10% PAC (92.7%) > 17% PAC (91.3%) > 2.7% Alum (88.1%).

Rats are one of the most widely used animals in biomedical sciences because their metabolism and physiology are comparable to humans. In recent years, gene-targeted models have been developed using various animal species utilizing engineered nucleases such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated gene (Cas). It has recently become possible to efficiently transfect CRISPR/Cas into embryos via electroporation. However, electroporation can damage fertilized eggs; therefore, it is important to determine the optimal embryo culture conditions. A standardized approach for routine and reproducible rat transgenesis will render rat models more accessible for research. We performed experiments to obtain rat embryos with efficient superovulation and synchronization, and to investigate the appropriate medium conditions for pronuclear stage embryos subjected to electroporation stimulation for the introduction of engineered nuclease.

본 연구에서는 꼬막(cockle), 전복(abalone), 가리비(scallop) 패각을 이용하여 중금속 제거효율 평가를 수행하였다. 꼬막, 전복, 가리비의 주 구성광물은 각각 아라고나이트, 아라고나이트와 방해석, 방해석으로 구 성되어 있다. 각 패각들의 비표면적은 2.7241 m2/g에서 4.5481 m2/g까지 다양하며 가리비 > 전복 > 꼬막이다. 반응 후 중금속 분석 결과 As는 패각에 의한 흡착이나 pH 상승에 의한 침전 제거 효과가 나타나지 않았다. 납은 반응 초기에 모든 패각 시료에서 모두 제거되었다. 카드뮴과 아연은 매질에 따라 약간의 차이가 있지만 제거 효율은 가리비 > 전복 > 꼬막 순으로 나타났다. 중금속 제거 효율은 가열 시료가 원시료 비해 약간 높 으며, 비표면적이 클수록 높은 경향이 있다.

In order to photocatalytically treat organic matter (CODCr) and chromaticity effectively, chemical coagulation and sedimentation processes were employed as a pretreatment of the leachate produced from landfill in Jeju Island. This was performed using FeCl3･6H2O as a coagulant. For the treated leachate, UV/TiO2 and UV/TiO2/H2O2 systems were investigated, using 4 types of UV lamps, including an ozone lamp (24 W), TiO2 as a photocatalyst, and/or H2O2 as an initiator or inhibitor for photocatalytic degradation. In the chemical coagulation and sedimentation process using FeCl3･6H2O, optimum removal was achieved with an initial pH of 6, and a coagulant dosage of 2.0 g/L, culminating in the removal of 40% CODCr and 81% chromaticity. For the UV/TiO2 system utilizing an ozone lamp and 3 g/L of TiO2, the optimum condition was obtained at pH 5. However, the treated CODCr and chromaticity did not meet the emission standards (CODCr: 400 mg/L, chromaticity: 200 degrees) in a clean area. However, for a UV/TiO2/H2O2 system using 1.54 g/L of H2O2 in addition to the above optimum UV/TiO2 system, the results were 395 mg/L and 160 degrees, respectively, which were within the emission standard limits. The effect of the UV lamp on the removal of CODCr, and chromaticity of the leachate decreased in the order of ozone (24 W) lamp > 254 nm (24 W) lamp > ozone (14 W) lamp > 254 nm (14 W) lamp. Only CODCr and chromaticity treated with the ozone (24 W) lamp met the emission standards.

본문은 한중 공업품의 발전현황을 바탕으로 중국과 RCEP 회원국 2011~2020년에 대해 패널데이터로 시변적(Time-Varing) 확률적 변경 중력모형을 구축하여 한중 양국의 공업품의 무역 효율과 잠재력에 대해 분석한다. 연구를 통해 경제규모, 노동력, 공동적 언어가 한중 양국의 공업품 무역에 긍정적인 영향을 미치면 지리적 거리에서 부정적 작용을 미친다. FTA협정, 대외 직접투자는 양국의 무역 효율 상승을 추진과 비교적 높은 경제자유도와 양호한 상업 환경은 양국의 수출무역의 억제를 감소시킨다. 한중 공업품 무역효율은 RCEP 회원국 순위에서 중후반에 위치하고 있어 자본 기술 집약형 제품의 수출 성장공간이 비교적 크다. 중국은 핵심 기술 경쟁력 향상으로 기업환경 개선하여 한중 양국의 협력을 강화하여 RCEP 제도의 긍정적 측면을 충분히 발휘한다.

As a herbal supplement, Dioscorea batatas Decne (DBD) presents potent antioxidant activity and diverse health benefits. In the present study, functions of a 30 kDa glycoprotein isolated from DBD (hereafter, DBD glycoprotein) in the regulation of feed efficiency and fecal malodor in mice were explored. DBD glycoprotein produced protective effect against cytotoxicity induced by the ecotoxicological endocrine-disrupting substance bisphenol A in gastrointestinal epithelial HT-29 cells. To investigate its potential roles in the regulation of feed efficiency and fecal malodor, mice were administered an oral injection of DBD glycoprotein for 2 weeks. Compared with the control values, the weight of internal organs (liver, heart, kidney, and spleen) and levels of glutamate pyruvate transaminase, glutamate oxaloacetate transaminase, and lactic dehydrogenase were not significantly changed during DBD glycoprotein administration for 2 weeks. Interestingly, DBD glycoprotein improved feed efficiency and reduced hydrogen sulfide concentration without altering the ammonia level in mouse feces. Collectively, these results indicate that DBD glycoprotein is a functional agent that exerts gastrointestinal protective effects against ecotoxicological substances, improves feed efficiency, and reduces fecal malodor.

Damage to the natural environment is becoming increasingly complex in modern society, expanding to impact not only the environment but also society and the economy. Various systems and policies based on sustainability have been promoted internationally. Legal systems and policies based on evaluation systems such as land environment assessment and urban ecological status maps, have been implemented in Korea. However, most of Korea institutions and policies related to the natural environment have been directed toward the conservation of the natural environment, and restricted to in simple theoretical frameworks with various limitations. Therefore, this study analyzed the definition and value of the natural environment for a fundamental conceptual approach to the valuation of the natural environment. Based on this, we modeled the policy process for a flexible evaluation system suitable for the actual situation of Korea natural environment through a review of the integration of environmental policy proposed in Europe.

In this study, we evaluated the effect of the type of sewage sludge (digested, non digested) on drying efficiency according to the polymer injection rate. The drying characteristics were shown using a near-infrared ray (NIR) and a microwave. As a result of the drying characteristics with NIR at a polymer dose ratio of 8%, the heating up period is up to 6 minutes after the start of the drying experiment. Afterwards, the constant rate drying period of the digested sludge (A, C and G sites) was 6 minute → 18 minute, showing a rapid decrease in moisture. On the other hand, non digested sludge (B, D, E, F, H, I, J and K sites) showed gradual drying characteristics compared to digested sludge until complete drying (10%). As the polymer dose ratio of 10% and 12%, the heating up period for digested sludge is up to 6 minute after the start of the experiment. Afterwards, the constant rate drying period of the digested sludge was 6 minute → 20 minute, showing a rapid decrease in moisture. On the other hand, the heating up period of non digested sludge was up to 10 minute after the start of the experiment, and the constant rate drying period was 10 minute → 22 minute, which was shorter than digested sludge. As a result of the drying characteristics with microwave at a polymer dose ratio of 8%, 10% and 12%, the constant rate drying period the digested sludge was 4 minute → 20~22 minute, showing a rapid decrease in moisture. On the other hand, non digested sludge of the constant rate drying period was 4 minute → 22~30 minute, which was longer than digested sludge.

코로나 상황(Covid-19)의 장기화로 인해 현장에서 이루어지던 많은 교육과정들이 온라인 시스템을 활용한 교육으로 전환되고 있으며, 예비교사 교육과정의 필수 과정인 교육실습 역시 온라인 교육으로 시행되었다. 본 연구의 초점은 비대면 교육시대의 온라인 교육실습을 위한 실습지도교사와 예비교사의 요구를 분석하는 것이다. 이를 위해, 첫째, 2019년 충청권 교사연구회를 통해 드러난 실습지도교사와 예비교사들의 온라인 플랫폼에 요구되는 콘텐츠와 세부 기능에 대한 요구를 파악하고, 2020년 5개의 충청권 실습학교들이 실시한 온라인 교육실습의 내용을 살펴보아 현장의 요구가 어떻게 실천되었는지를 살펴보았다. 둘째, 2020년 온라인 교육실습을 경험한 각기 다른 대학교 소속 4명의 예비교사들의 경험을 살펴 기억해야 할 가치와 교육실습의 의미에 대해 고찰해보았다. 연구의 결과로서, 실습지도교사는 실습의 전 과정의 흐름을 드러내는 콘텐츠의 중요성, 학생들은 실제실습의 과정에 초점이 맞춰진 콘텐츠들의 중요성을 언급했다. 실습지도교사와 예비교사 모두 소통을 중심으로 한 온라인 교육실습의 가치를 드러냈다.

Repeated use of land is depleting future resources and causing many ecological problems, prompting the need for a natural resource policy focusing on effective conservation. This study aims to identify methods based on international cases useful for introducing sustainable conservation of domestic natural resources. Currently, South Korea has developed and enforced many management and evaluation strategies for natural resources. However, due to limitations on policies and management, they show signs of strain. Therefore, this study compares and analyzes international conservation policies for nature and scenery, such as Germany’s impact mitigation regulation, the USA’s HEA (habitat equivalency analysis) and REA (resource equivalency analysis) policies, and Japan’s three laws for landscape and greenery, to achieve the following three goals: first, find natural resources suitable for South Korea and define them. Second, plan goals for mitigation of total natural resources and build a basis for them. Third, establish effective complete plans for evaluating the total amount of natural resources.

지금까지 컨테이너 자동화 터미널의 설계 및 운영 모델 개발은 주로 수출입 화물의 양적·하 기능에 특화된 서구 항만을 대상으로 수행되었기 때문에, 부산항처럼 다양한 On-Dock 서비스가 요구되는 컨테이너 항만에서는 자동화 터미널의 도입과 운영에 많은 제약이 따른다. 이에 본 연구의 목적은 부산항을 사례로 현재 컨테이너 물동량 구조와 터미널 내부 운영 특성을 진단하고, 기존 자동화 터미널 운영 모델의 부 분적인 변경을 통해 효과적인 공컨테이너 관리와 함께 터미널 운영비용을 절감하는 방안을 제시하는 것이다. 기존 수직 배열 자동화 컨테이너 터미널에 ‘인터체인지 이송 모델’을 적용하여 시뮬레이션 한 결과, 수정된 운영 모델은 구내 이송장비를 추가로 투입해야 하는 불리함에도 불구 하고 기존 운영 모델 대비 최대 22%의 TAT 단축과 함께 연간 터미널 매출의 9.4%에 달하는 운영비용 절감이 가능한 것으로 나타났다.

Ulmus davidiana Nakai (UDN) has been traditionally used as a herbal medicine in Korea. In the present study, we investigated the anti-ecotoxic potential of a 116 kDa glycoprotein isolated from UDN (UDN glycoprot ein) in regulating fecal malodor and feed efficiency in mice. We found that UDN glycoprotein (200 μg/ml) has an inhibitory effect on the cell death induced by an ecotoxicological endocrine disrupting chemical, bisphenol A, in colon epithelial HT-29 cells. UDN glycoprotein did not show significant differences regarding the weight of ecotoxicity-related organs (liver, heart, kidneys, and spleen) and the levels of serum glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, and lactate dehydrogenase in mice for 2 weeks, compared to the control. Additionally, UDN glycoprotein reduced the levels of hydrogen sulfide and ammonia as markers of fecal malodor in mice. Interestingly, UDN glycoprotein can improve the mouse feed efficiency. In conclusion, our data indicate that anti-ecotoxicological UDN glycoprotein has the ability to increase the feed efficiency and reduce the fecal malodor by maintaining the viability of colonic epithelial cells in mice.

A new chemosensor based on a self-assembled system has been devised to detect Hg2+ions efficiently. We demonstrated that the amphiphilic building blocks consisting of pyrene and boronic acid (1) aggregate in aqueous solutions and provide an outstanding sensing platform for sensitive detection. The self-assembled 1 exhibited high selectivity and sensitivity for Hg2+ion detection via fluorescence quenching, where the Hg2+ion detection ensued from a fast transmetallation of 1. The Stern-Volmer (SV) quenching constant for its fluorescence quenching by Hg2+ions was approximately 1.58 × 108 M-1. In addition, self-assembled 1 exhibited excellent sensing abilities at nano-molar concentration levels when tap water and freshwater samples were contaminated with of Hg2+ ions.

Seasonal changes in the CO2 fixation rate and water-use efficiency in the leaves of six evergreen and two deciduous broad-leaved tree species on Jeju Island, Korea, were measured using a portable photosynthesis analyzer, to identify which species are most efficient in taking up CO2 from the air. The CO2 fixation rate was high in the deciduous species in spring and summer and decreased in fall, whereas it was high in the evergreen species in summer and fall and decreased in winter. The rate remained high in the deciduous tree Prunus yedoensis from spring to fall (> 7.1 μmol CO2/m2/s) and in two evergreen trees, Castanopsis cuspidata var. sieboldii and Cinnamomum camphora, in summer and fall (7.0 9.9 μmol CO2/m2/s). Therefore, these tree species fix atmospheric CO2 effectively. The water-use efficiency was higher in evergreen species than in deciduous species regardless of the season. Exceptionally, it was high in the deciduous species Zelkova serrata in spring and summer (> 100 μmol CO2/mol H2O), suggesting that Z. serrata is a useful tree for dry conditions due to its tolerance of water stress. The regressions of the CO2 fixation rate versus the evaporation rate and stomatal conductance were linear and non-linear, respectively. This suggests that the stomatal activity of leaves plays an important part in CO2 fixation of plants. In conclusion, C. cuspidata var. sieboldii, C. camphora, and P. yedoensis should be planted along roads or in urban spaces for the greening of cities and mitigation of CO2 concentrations in the air.

본 연구에서는 빛 감성친화형 콘크리트에 광촉매를 적용하여 대기질 및 실내공기질을 개선하기 위한 LEFC 블록을 개발하고자 하였다. LEFC에 광촉매를 적용하게 되면 자외선 입사면 반대편에서도 투과로 인한 자외선이 존재하여 광촉매가 반응함으로써 일반 건축 자재를 적용한 경우보다 광촉매 반응효율이 크게 상승한다. 따라서 광촉매를 LEFC에 적용하기 위해 슬럼프, J-ring, L-box 테스트를 통한 자기충전성능을 평가하여 최적 배합을 결정하였고, 압축 및 휨 강도 시험을 통해 역학성능을 평가하였다. 그리고 TiO2 분포도를 확인하기 위해 SEM과 EDS 분석을 실시하였다. ALC골재와 단열재 적용으로 광촉매 사용량을 줄이고 단위중량을 감소시키는 방안을 활용하여 광촉매 효율을 증가시키는 빛투과 콘크리트 블록을 제작하였고, 향후 건조수축 등의 문제점 개선 및 NOx 제거 실험을 통한 LEFC 블록 성능 평가를 진행하고자 한다.

최근 노후화된 기반시설물의 지속적 증가와 시설물 안전에 대한 요구가 증대함에 따라 정부에서는 ‘18.12.31 지속가능한 기반시설관리 기본법을 제정, 공표하고 ’20.1.1 시행을 예고하였다. 본 연구는 기반시설관리법 적용대상인 시설의 성능개선 대상 사업에 일관적으로 적용할 수 있는 성능개선 의사결정에 필요한 성능개선 공통기준 프레임워크를 제안하는 것이다. 국내·외 유지관리 및 성능개선 현황조사 및 유사 제도·관리체계 검토를 통해 기반시설 성능개선의 적정성 판단을 유도하는 평가요소를 도출하였으며, 이를 통해 「기반시설관리법」의 효과적 실행에 필요한 세부 시행기준 마련 및 관리역량을 확보하고 기존 시설물의 성능개선을 위해 투입되는 예산의 효율성 확보하는데 기여할 수 있을 것으로 기대한다.

The purpose of this study was to evaluate the effects of different Hydraulic Retention Times (HRTs) on the contaminant removal efficiency using Aerobic Granular Sludge (AGS). A laboratory-scale experiment was performed using a sequencing batch reactor, and the Chemical Oxygen Demand (COD), nitrogen, orthophosphate removal efficiency, AGS/MLSS ratio, and precipitability in accordance with the HRT were evaluated. As a result, the COD removal efficiency was not significantly different with the reduction in HRT, and at a HRT of 6 h, the removal rate was slightly increased owing to the increase in organic loading rate. The nitrogen removal efficiency was improved by injection of influent division at a HRT of 6 h. As the HRT decreased, the MLSS and AGS tended to increase, and the sludge volume index finally decreased to 50 mL/g. In addition, the size of the AGS gradually increased to about 1.0 mm. Therefore, the control of HRT provides favorable conditions for the stable formation of AGS, and is expected to improve the contaminant removal efficiency with the selection of a proper operation strategy.

정부는 국가 차원에서 물류인프라의 확충과 물류전문기업의 육성을 통해 물류기업의 경쟁력 향상과 국제물류시장의 주도권을 확보하기 위해 지속적인 노력을 실시해오고 있으며, 특히 동북아 지역의 경제규모 및 교역량이 자치하는 비중이 급증함에 따라 동북아 지역의 물류 네트워크 선정을 위해 다양한 정책을 추진하고 있다. 이러한 정부의 정책의 일환으로 2006년부터 종합물류기업 인증제도를 도입하여 시행하고 있다. 이 제도는 물류정책기본법에 근거하여 설립된 정부의 물류전문기업 육성방안의 대표적인 정책 중 하나이다. 그러나 이 제도로 인해 물류기업에 대한 신뢰성을 높여 물류산업의 선진화 및 효율화에 기여하였다는 주장과 동 제도로 인해 기업의 부담과 대기업 위주의 시장 통폐합 우려 등의 부정적인 의견이 대립되고 있다. 이에 본 연구는 이러한 논란이 있는 현 시점에서 종합물류인증 기업 중 물류창고기업을 대상으로 효율성 분석을 통해 비효율의 실태와 개선방안을 제시하고자 한다. 분석방법으로는 DEA 분석을 통해 종합물류인증기업의 경영효 율성을 분석하며 비효율적인 기업의 투사값을 제시하며 벤치마킹의 대상이 될 수 있는 기업들의 참조집합을 제시하고자 하며 또한 분석결과 를 통해 벤치마킹의 대상이 되는 기업들을 제시하였다.