본 연구의 목적은 '날씨와 기후' 단원에 대한 수업 후, 수업방법(설명식 수업과 발견식 수업)과 학습자의 인지양식에 따른 학업파지 효과를 조사하는 것이다. 연구대상은 광주에 있는 남자고등학교의 1학년 185명과 남여공학고등학교의 1학년 189명을 대상으로 하였다. 연구대상 학생들 중 남자고등학교의 92명과 남여공학고등학교의 95명을 설명식수업집단으로, 그리고 남자고등학교의 93명과 남여공학고등학교의 94명을 발견식 수업집단으로 선정하였다. 모든 학생들은 그들의 인지양식에 따라 장 독립적 학습자, 중간적 학습자, 장 의존적 학습자로 분류되었다. 연구 결과는 다음과 같이 요약할 수 있다. 첫째, 지구과학 학습내용의 수업 3주일 후 학업파지검사에서 발견식 수업방법이 설명식 수업방법에 비해 이해와 적용영역에서 더 효과적인 것으로 나타났다. 그러나 지식영역에 있어서는 유의미한 차이가 없었다. 둘째, 학업파지검사에서 장 독립적 인지양식의 학습자들이 장 의존적 인지양식의 학습자들에 비해 이해와 적용영역에서 더 효과적인 것으로 나타났다. 셋째, 학업파지검사에서 수업방법과 학습자의 인지양식 간의 상호연관성에 대한 유의미한 차이는 없었다.

영양염류의 농도와 수리학적체류시간에 따른 달뿌리풀의 질소ㆍ인 흡수 실험 결과로서 NH4-N, NO3-N, PO4-P의 흡수량은 각각 체류시간에 따라 유의한 영향을 미쳤으며(F=44.93, 95.52, 12.70, Pm2, 평균 수질농도 0.308 NH4-N, 1.461 NO3-N, 0.348 PO4-P mg/L, 체류시 간 1일~ 5일 범위에서 1 m2 1일 기준의 흡수량이 각각 7.31~20.15 NH4

신문 용지용(用) 지료(紙料)의 조성조건(調成條件)에 따른 보류(保留)의 변화를 연구(硏究)한 결과 다음과 같은 사실을 알수가 있었다. 1. 온도(溫度)의 상승(上昇)에 따라 보류(保留)는 지료(紙料)의 종류 및 배합비(配合比)에 관계없이 감소(減少)하였으며 GP보다 DIP가 온도(溫度)변화에 민감(敏感)하였다. 2. pH변화에 따른 보류(保留)의 변화는 GP와 DIP 및 GP/DIP=50/50 모두 pH5에서 보류(保留)가 가장 높았으며 pH 5보다 높거나 낮으면 감소(減少)하였고 DIP가 GP보다 감소(減少)가 적었다. 3. Alum첨가(添加)에 따른 보류(保留)의 변화는 GP와 GP/DIP=50/50의 경우 2% 첨가(添加)에서 보류(保留)가 가장 높았고 DIP는 3% 첨가(添加)에서 가장 높았다. 4. 보류(保留)는 지료(紙料)의 응집작용(凝集作用)과 밀접한 관련이 있었다.

1. "과피원판저지대법"으로 사과 탄달병 방제약제의 지속성, 전착제 및 살충제혼용의 효과를 검정하였다. 2. 살균제를 뿌린 후 시일이 경과할 수록 살균력은 줄었다. 공시 약제 중에서 Difolatan의 약효가 가장 컸으며 15일 후에도 의 살균력이 있었고 그 다음은 Tuzet, Phaltan, 보르도액 , Delan의 순위였다. 3. 인공강우량이 많을수록 Tozet의 약효는 줄었으나 전착제를 첨가함으로색 약제의 유실을 경감할 수 있었다. 시판 상품인 리노 1,2호 및 Tween 20 보다도 탈지분유 및 콩추출액의 효과가 현저히 좋았다. 4. Phaltan을 단용하는 것보다 EPN, Folithion, Parathion 및 Lebaycid 를 섞어서 실온에 12일간 두어도 어느 것이나 살균핵과에는 현저한 차이가 없었다.

This study was carried out to analyze water cycle characteristics and evaluate water retention function in Jeju Gotjawal forest from 2013 to 2017. The average ratio of throughfall, stemflow, interception loss in Seonhul Gotjawal (SH) and Cheongsu Gotjawal (CS) was 43.1%, 15.8%, and 41.1%, respectively. Rainfall-throughfall, rainfall-stemflow, and rainfall-interception loss were expressed as linear regression equation (p<0.001). The comparison results showed that SH was higher than CS (p<0.05), indicating that the canopy area had an important effect on the difference in stand structure. The average water resources retention rate of the Gotjawal region was 41.9%, which is similar to the total water resources retention rate (40.6%) of Jeju Special Self-Governing Province (JSSGP). Currently, the development of Gotjawal is in progress in JSSGP. The development of Gotjawal will lead to a decrease in the water resources retention rate due to changes in the surface environment such as an increase in impervious areas, which will affect the total groundwater content of JSSGP. Therefore, the conservation of the Gotjawal area is judged to be very important from the point of view of water conservation.

The aim of this study was to investigate the amount (i.e., retention volume) and chemical composition of Natural volatile organic compounds (NVOCs) across different sites in a temperate forest. The three forest sites that were considered include riparian zones (site 1), streams (site 2), and densely-canopied areas (site 3). From May to October 2021, a mini pump was used to measure the collected NVOCs. These measurements were conducted once a month, from 10:30 am to 11:30 am; these times encompass peak visitation times. In the tree layers of the site 1 and 2, Quercus acuta was dominant, whereas Camellia japonica dominated their subtree layers. On the other hand, the tree layer of site 3 was dominated by Castanopsis sieboldii, whereas Camellia japonica dominated its subtree layer. The retention volume and chemical composition of NVOCs was as follows: benzaldehyde (107.528ppm), α-pinene (37.868ppm), linalool (16.258ppm), eucalyptol (14.818ppm), and sabinene hydrate (14.679ppm). In particular, the retention volume of benzaldehyde decreased as temperature increased. In contrast, the retention volume of α-pinene increased as the temperature increased. The differences in forest topography across the studies sites were in the following order: riparian area> forest area> stream area.

This study investigates determinants of talent retention in textile and garment companies located in Vietnam’s Binh Duong province to propose feasible actions for their sustainable development in the current context of competition on the labor market. This study uses selfcompleted questionnaires to collect data which are then analysed with statistical methods including scale reliability, exploratory factor analysis, and multiple linear regression. Specifically, results from an official survey of 129 people who are regarded as talents in related companies show that there are ten determinants, ranked in descending order of their importance, including: working environment; training and promotion opportunities; salary and benefits; personal loyalty; relationship with colleagues; nature of work; organizational recognition; type of ownership; relationship with superiors; and working experience. Moreover, it is also found that foreign companies are better in retaining their talents than private domestic ones. These findings suggest that, depending on their available resources, organizations need to focus on some of these factors to improve their talent retention; among them, it is critical to provide creative space or create conductive working environment by providing talents with proper tools and equipment for them to feel excited with their work and get things done in an optimal, efficient and effective manner.

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.

In this study, to analyze the change of mass of concrete structure subjected to fire damage, cement paste was exposed at high temperature to maintenance time and analyzed mass change characteristics by TGA analysis. As a result of analysis, the mass reduction rate of cement paste decreased with increasing heating time after heating at high temperature.

Vertical farming systems offer many advantages in urban spaces. They have also been proposed as an engineering solution to increase the productivity per unit area of cultivated land by extending crop production in the vertical dimension. However, soil water retention is a major constraint affecting the plant environment. This study analyzed the effects of growth environment of Tropaeolum majus and Fragaria spp., on the vertical farming system, by using four different types of cover material types including sphagnum moss (Control), a shading net (S.N.), multi-layered fabric (M.L.F.), and non-woven fabric (N.W.F.). The volumetric soil moisture contents and plant characteristics were investigated from May to September 2014. Plant materials were individually cultivated in hanging baskets measuring 30×17×17 cm, filled with a mixture of soil and perlite, and placed at 1.5m height. Each treatment was performed in quadruplicate and consisted of five plants, amounting to a total of 20 plants. The analysis indicated that different covers were associated with multiple functions and soil water retention improvements may have a positive impact on the vertical farming system. The difference in soil water retention increased in the following order: M.L.F. > Control > N.W.F. > S.N.. Furthermore, the differences in plant height and survival rate increased in the following order: M.L.F. > Control > N.W.F. > S.N. Therefore, M.L.F yielded satisfactory good response for the vertical farming system of cover materials. Our results clearly demonstrate that vertical spaces represent an attractive alternative to urban farming and suggest that further increases in yield may be achieved via different cover materials in vertical farming using hanging baskets.

This study was performed to investigate the effects of different cooking methods (boiling, roasting, stir-frying, and deep-frying) on folate retention in 6 kinds of mushrooms (Beech-, button-, Juda’s ear-, oak-, oyster-, and winter-mushrooms) frequently consumed in Korea. In order to assure reliability of analytical data, trienzyme extraction-L casei method was verified and analytical quality control was also evaluated. Folate contents of mushrooms varied by 6.04-64.82 g/100 g depending on the type of mushrooms. and were significantly affected by cooking methods. Depending on cooking methods, folate contents of mushrooms decreased by 22-48%, 2-31%, and 17-56% for Juda’s ear-, oak- and oyster-mushrooms, respectively, while 17-90% of folate was increased in Beech mushroom. Overall, the largest weight loss was found in boiled mushrooms, but the lowest one in deep-fried samples. True folate retention rates considering processing factor were less than 100% for all cooked mushrooms except for Beech samples. Overall, folate loss was the largest by boiling with water but the smallest by deep-frying. Both accuracy and precision of trienzyme extraction-L-casei method were excellent based on a recovery close to 100% and coefficient variations less than 3%. Quality control chart of folate analysis (n=26) obtained during the entire study and an international proficiency test (z-score=-0.5) showed that trienzyme extraction-L casei method is reliable enough for production of national folate database.

이전에 학습한 자료에 대하여 시험을 쳐 보는 것은 강력한 학습 이벤트로 작용할 수 있다. 이를 시험 효과라고 하는데, 본 연구에서는 시험 효과 검정을 위한 중세국어-현대국어 단어쌍을 개발하 여 사용하였다. 본 연구에서는 이를 활용하여 초기 테스트, 단서 회상 테스트, 단기 파지 간격에 따른 집단 간의 차이를 살펴보았다. 그 결과, 초기 테스트 집단이 매우 유의미한 결과를 나타내었 다. 이것은 학습 후 빠른 시간 안에 초기 테스트가 필요함을 강력히 지지한다. 그리고 단서 회상 테스트가 주어질 경우 더욱 그 효과가 뛰어났다. 그러므로 실제 교실 수업에서도 학습 후 테스트나 퀴즈의 형태를 통해 학습자의 학습을 도울 수 있으며, 형성평가 등을 적극 활용한 교수․학습을 설계할 것을 제안한다.

The mechanism of micro-bubble generation with a pump is not clarified yet, so the design of water treatment systems with a micro-bubble generating pump is based on trial and error methods. This study tried to explain clearly quantitative relationships of experimental micro-bubble concentration (Cair) of continuous operation tests with a micro-bubble generating pump and theoretical air solubility. Operation parameters for the tests were discharge pressure (Pg), water (Qw0) and air (q0) flow rates, orifice diameter (DO), and retention time (t). The experimental micro-bubble concentrations (Cair) at 4.8 atm of discharge pressure (Pg) were in the range of 21.04 to 25.29 mL/L. When the retention time (t) by changing the pipe line length (LP) increased from 1.22 to 6.77s, the experimental micro-bubble concentrations (Cair) increased from 25.86 to 30.78 mL air/L water linearly. The dissolved and dispersed micro-bubble concentrations (Cair) are approximately 4 times more than the theoretical air solubility.