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The impacts of the experince of donation for education to improve the teaching efficacy of pre-technology teacher with Invent touring activity (발명체험 교육기부활동이 예비기술교사의 교수 효능감에 미치는 영향)

  • Choi, Yu-Hyun;Lim, Yun-Jin;Lee, Eun-Sang;Lee, Dong-Won
    • 대한공업교육학회지
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    • v.38 no.2
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    • pp.156-175
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    • 2013
  • The purpose of this study was to verify that the impacts of experience of donation for education to improve the teaching efficacy of pre-technology teacher. The Invention experience of donation for education was performed with Invent-touring sponsored by Chunnam National University Invention Education Center for Teachers and was included by development of creative problem solving program, program execution and evaluation. Research participants were Technology education Majors and minors 20 students. The active locations were D children community center, K alternative school, D Elementary School and D middle school. For the study, various literature researches were reviewed intensively about donation for education and teaching efficacy. The instrument for the study was the modified STEBI(Science Teaching Efficacy Beliefs Instrument) for technology education by 3 experts. This study was designed by single group pre and post test design (One-Group Pretest-Posttest Design) and was conducted by the pre-test and post-test. Check the reliability of the tool was conducted with Cronbach ${\alpha}$ coefficient analysis, pre-test 0.840, post-test 0.746. The analysis of data from the 5% significance level, paired sample t-test was performed using the SPSS 19.0 statistical tool. The results were as follows: 1. Teaching efficacy of pre-technology teachers who participated in the invention experience for educational donation technology has improved. 72. The qualitative study was performed by the interviews with students who participated in. Humanism was positively change and learning opportunity was provided to develop the competence of technology education teacher. Based upon the conclusion of this study, the donation activity for invention education need to use learning strategies for pre-technology teacher to improve teaching efficacy.

Spatio-temporal Variations in the Dynamics and Export of Large Wood in Korean Mountain Streams (우리나라 산지계류에 있어서 유목 동태의 시.공간적 다양성과 그에 따른 유출 특성)

  • Seo, Jung Il;Chun, Kun Woo;Kim, Suk Woo;Im, Sangjun
    • Journal of Korean Society of Forest Science
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    • v.101 no.3
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    • pp.333-343
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    • 2012
  • In-stream large wood (LW) has a critical impact on the geomorphic characteristics relevant to ecosystem management and disaster prevention, yet relatively little is known about variations in its dynamics and subsequent export on the watershed-scale perspective in Korea. Here we review variations in the dynamics and subsequent export of LW as a function of stream size, which is appropriate for Korean mountain streams. In upstream channels with narrow bankfull widths and low stream discharges, a massive amount of LW, resulting from forest dynamics and hillslope processes, may persist for several decades on valley floor. These pieces, however, are eventually transported during infrequent debris flows from small tributaries, as well as peak hydrology in main-stem channels. During the transport, these pieces suffer fragmentation caused by frictions with boulders, and stream bank and bed. Although infrequent, these events can be dominant processes in the export of significant amounts of LW from upstream channel networks. In downstream channels with wide bankfull widths and high stream discharges, LW is dominantly recruited by forest dynamics and bank erosion only at locations where the channel is adjacent to mature riparian forests. With the LW pieces that are supplied from the upstream, these pieces are continuously transported downstream during rainfall events. This leads to further fragmentation of the LW pieces, which increases their transportability. With decreasing stream-bed slope, these floated LW pieces, however, can be stored and form logjams at various depositional sites, which were developed by interaction between channel forms and floodplains. These pieces may decay for decades and be subsequently transported as particulate or dissolved organic materials, resulting in the limitation of LW fluvial export from the systems. However, in Korea, such depositional sites were developed in the extremely limited streams with a large dimension and no flood history for decades, and thus it does not be expected that the reduction of LW export amount, which can be caused by the long-term storage. Our review presents a generalized view of LW processing and is relevant to ecosystem management and disaster prevention for Korean mountain streams.

Quality Characteristics of Ginseng Seed Oil Obtained by Different Extraction Methods (추출방법에 따른 인삼씨유의 품질특성)

  • Kim, Ji-Eun;Lee, Seul;Yoo, Kyung-Mi;Lee, Kyoung-Hae;Kim, Kyung-Tack;Lee, Myung-Hee;Hwang, In-Kyeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.3
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    • pp.439-445
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    • 2014
  • This study aimed to determine the quality characteristics of ginseng seed oil as well as evaluate the efficacy of ginseng seed oil as a food resource. Ginseng seed oil was obtained by different extraction methods; from solvent extraction oil, supercritical fluid extraction oil, and screw pressed extraction oil. Total unsaturated fatty acids were present at 97.72~97.92%. Oleic acid (80.13~81.16%) was the highest, followed by linoleic acid (14.98~15.69%). The total phenol content (mg gallic acid equivalent/100 g oil) was higher in screw pressed extraction oil ($56.32{\pm}1.47$) compared to others. ${\gamma}$-Tocopherol was only present in ginseng seed oil and screw pressed extraction oil showed the highest levels of ${\gamma}$-tocopherol ($5.95{\pm}0.25$ mg/100g oil) among the tested samples. Screw pressed extraction oil showed the greatest oxidative stability with an induction time of 16.58 hours. Acid values and peroxide values of ginseng seed oil increased with increasing storage period. The total phenol and ${\gamma}$-tocopherol contents were higher in screw pressed extraction oil than in other ginseng seed oils, which suggests that screw pressed extraction oil has the greatest oxidative stability.

Inhibitory Activities of Water Extracts of Black Ginseng on HCl/Ethanol-Induced Acute Gastritis through Anti-Oxidant Effect (흑삼 열수 추출물의 항산화 효과를 통한 염산/에탄올로 유발된 위염 억제 작용)

  • Kim, Min Yeong;Kwon, O Jun;Noh, Jeong Sook;Roh, Seong-Soo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.9
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    • pp.1249-1256
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    • 2016
  • Black ginseng (BG) obtained by a 9-fold steaming process of Panax ginseng has been reported to have anti-oxidative, anti-obesity, and anti-diabetes effects. The current study evaluated the protective effect of BG by steaming time in an HCl/ethanol-induced acute gastritis model. BG was divided into four samples according to steaming-drying processing (Gin1, Gin3, Gin6, and BG). High performance liquid chromatography analysis, free radical scavenging activity, and total phenol and flavonoid contents were examined in ginseng and four BG samples. Compared with ginseng, BG showed a stronger radical scavenging effect and higher contents of total phenol and flavonoids. To evaluate the anti-gastritic effect of BG, mice were distributed into five groups: normal mice (N), acute gastritic mice with distilled water (CON), acute gastritic mice with 100 mg/kg of ginseng (Gin0), acute gastritic mice with 100 mg/kg of BG (BG), and acute gastritic mice with 10 mg/kg of sucralfate (SC). After 1 hour of pre-treatment with water, extracts (Gin0 and BG), or drug (SC), experimental groups except for N were orally administered 0.5 mL of 150 mM HCl/60% ethanol (v/v) mixture. Blood was collected 1 hour later from the heart, and gastric tissue was harvested. Reactive oxygen species (ROS) levels were measured in serum, and related protein expression was examined by Western blot assay. In HCl/ethanol-induced acute gastritic mice, treatment with ginseng or BG improved mucosal damage in the histological evaluation. The serum ROS level significantly decreased in the BG-treated group compared with the CON group. Furthermore, expression of inflammatory cytokines significantly decreased in the BG-treated group compared with the CON group. Based on these results, antioxidant and anti-gastritic activities of ginseng were enhanced by streaming-drying processing, in part due to an increase in biological active compounds.

Analysis of Enhancement Effect and Attachment Ability of Beneficial Intestinal Microflora in Puffed Grain Foods Using Confocal Laser Scanning Microscopy (곡물 소재 팽화식품에서 장내 유익균의 증진 효과 분석 및 공초점 현미경을 이용한 부착능 평가)

  • Jeong, Myeong-Kyo;Oh, Do-Geon;Kwon, Oh-Sung;Jeong, Jun-Young;Lee, Ym-Shik;Kim, Kwang-Yup
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.9
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    • pp.1071-1080
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    • 2017
  • This study examined the adhesiveness of beneficial intestinal bacteria to whole-grains using confocal scanning laser microscopy (CLSM), to demonstrate the prebiotic effects of whole-grains, and to develop prebiotic puffed snacks with these whole-grains. CLSM has been used to observe the adhesiveness of Lactobacillus acidophilus, which belongs to beneficial intestinal bacteria, to whole-grain powders using optical sectioning techniques. The enhanced effects on the growth of beneficial intestinal bacteria with the hot water grain extract were verified using an indirect count method. Finally, a puffed snack was produced with the prebiotic effect and the quality was evaluated by checking the chromaticity and degree of hardness. As a result, L. acidophilus exhibited adhesive ability to whole-grain powders and growth of selected beneficial intestinal bacteria were improved significantly. The Hunter L value of the developed puffed snack increased when seasoning was added. The hardness of the puffed snack with seasoning was higher than that of the control. The results of a sensory evaluation showed that the puffed snack with seasoning was highly rated in the overall preference compared to the control.

Effect of Plasma-activated Water Process on the Growth and Functional Substance Content of Lettuce during the Cultivation Period in a Deep Flow Technique System (담액수경재배 시스템에서 플라즈마수 처리가 상추의 생육 및 페놀류 함량에 미치는 영향)

  • Noh, Seung Won;Park, Jong Seok;Kim, Sung Jin;Kim, Dae-Woong;Kang, Woo Seok
    • Journal of Bio-Environment Control
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    • v.29 no.4
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    • pp.464-472
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    • 2020
  • We suggest a hydroponic cultivation system combined with a plasma generator to investigate the changes in the growth and functional substance content of lettuces during the cultivation period. Lettuce seedlings of uniform size were planted in semi-DFT after seeding for 3 weeks, and the plasma-activated water was intermittently operated for 1 hour at an 8 hours cycle for 4 weeks. Lettuces grew with or without plasma-activated water with the nutrient solution in hydroponics culture systems. Among the reactive oxygen species generated during plasma-activated water treatment, brown spots and necrosis appeared in the individuals closer to the plasma generating device due to O3, and there was no significant difference in the growth parameters. While the rutin and total phenolic content of the lettuce shoot grown in the nutrient solution were higher than that of the plasma-activated water, epicatechin contents in plasma-activated water were significantly greater than the nutrient solution. However, in the roots, all kinds of secondary metabolites measured in this work, rutin, epicatechin, quercetin, and total phenolic contents, were significantly higher in the plasma-activated water than the control. These results were indicated that the growth of lettuce was decreased due to the reactive oxygen species such as ozone in the plasma-activated water, but the secondary metabolites in the root zone increased significantly. It has needed to use this technology for the cultivation of root vegetables with the modified plasma-activated water systems to increase secondary metabolite in the roots.

Analysis of Heating Characteristics of Multi-Layered Insulation Curtain with Silica Aerogel in Greenhouses (실리카 에어로겔을 이용한 다겹보온커튼의 온실 난방 특성 분석)

  • Jin, Byung-Ok;Kim, Hyung-Kweon;Ryou, Young-Sun;Lee, Tae-Seok;Kim, Young-Hwa;Oh, Sung-Sik;Kang, Geum-Choon
    • Journal of Bio-Environment Control
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    • v.29 no.4
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    • pp.320-325
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    • 2020
  • This study aimed to analyze thermo-keeping and economic feasibility by utilizing silica aerogel, which has been attracting attention as a new material, complementing the disadvantages of the conventional multi-layered thermal screen, and producing and installing multi-layered thermal screen. The multi-layered thermal screen used in the experiment was produced in two combinations using a non-woven fabric containing silica aerogel and measured and compared the temperature and fuel consumption changes due to differences in practice with the multi-layered thermal screen being sold and used on the market. Experimental results show that the temperature and relative humidity changes due to the differences of the multi-layered thermal screens in the single-span greenhouse and the multi-span greenhouse were small but remained almost the same temperature and relative humidity. It is judged that this shows that the multi-layered thermal screen using silica aerogel is not inferior to the conventional multi-layered thermal screen. As a result of a comparative analysis of heating energy, the aerogel-based multi-layered thermal screen reduced fuel consumption by about 15% in the single-span greenhouse and about 20% in the multi-span greenhouse compared to the conventional multi-layered thermal screen. It is clear that heating energy is saved as a greenhouse size and duration increase. It was found that the silica aerogel-based multi-layered screen was more breathable and warmer than the conventional multi-layered thermal screen, but It was found that the multi-layered screen used in the multi-span greenhouse was heavier and stiff compared with the conventional multi-layered thermal screen, indicating less workability and operability. Therefore, improvements were applied to the multi-layered screens used in the single-span greenhouses. It was confirmed that the replacement of internal insulation materials reduced thickness and improved stiffness so that there could be sufficient possibility for farmers to use.

An Investigation of Reliability and Safety Factors in RC Flexural Members Designed by Current WSD Standard Code (현행(現行) 허용응력설계법(許容應力設計法)으로 설계(設計)되는 RC 휨부재(部材)의 신뢰성(信賴性)과 안전율(安全率) 고찰(考察))

  • Shin, Hyun Mook;Cho, Hyo Nam;Chung, Hwan Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.1 no.1
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    • pp.33-42
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    • 1981
  • Current standard code for R.C. design consists of two conventional design parts, so called WSD and USD, which are based on ACI 318-63 and 318-71 code provisions. The safety factors of our WSD and USD design criteria which are taken primarily from ACI 318-63 code are considered to be not appropriate compared to out country's design and construction practices. Furthermore, even the ACI safety factors are not determined from probabilistic study but merely from experiences and practices. This study investigates the safety level of R.C. flexural members designed by the current WSD safety provisions based on Second Moment Reliability theory, and proposes a rational but efficient way of determining the nominal safety factors and the associated flexural allowable stresses of steel bars and concretes in order to provide a consistent level of target reliability. Cornell's Mean First-Order Second Moment Method formulae by a log normal transformation of resistance and load output variables are adopted as the reliability analysis method for this study. The compressive allowable stress formulae are derived by a unique approach in which the balanced steel ratios of the resulting design are chosen to be the corresponding under-reinforced sections designed by strength design method with an optimum reinforcing ratio. The target reliability index for the safety provisions are considered to be ${\beta}=4$ that is well suited for our level of construction and design practices. From a series of numerical applications to investigate the safety and reliability of R.C. flexural members designed by current WSD code, it has been found that the design based on WSD provision results in uneconomical design because of unusual and inconsistent reliability. A rational set of reliability based safety factors and allowable stress of steel bars and concrete for flexural members is proposed by providing the appropriate target reliability ${\beta}=4$.

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Why Your Manuscripts Were Rejected or Required a Major Revision: An Analysis of Asia Pacific Journal if Information Systems (MIS 논문의 '게재 불가' 및 '수정 후 재심사' 사유: Asia Pacific Journal of Information Systems 심사소견서 분석)

  • Lee, Choong-C.;Yun, Hae-Jung;Hwang, Seong-Hoon
    • Asia pacific journal of information systems
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    • v.19 no.2
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    • pp.179-193
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    • 2009
  • As the common saying attests, a publish-or-perish world, publishing is absolutely critical for academic researchers' successful careers. It is the most objectively-accepted academic performance criteria and the most viable way to attain public and academic recognition. Asia Pacific Journal of Information Systems(APJIS) has been recognized as the most influential domestic journal in Korean MIS field since July, 1991. Therefore, publishing in APJIS means your research is original, valid, and contributive. While most researchers learn how to publish an article in APJIS through a repetitive review process, thereby improving their chance of the' accepted' through their personal trial and error experiences, such valuable lessons and know-how tend to be kept personally and rarely shared. However, useful insights into research and publication skills could be also gained from sharing others' errors, neglect, and misjudgments which are equally critical in improving researchers' knowledge in the field (Murthy and Wiggins, 2002). For this reason, other academic disciplines make systematic efforts to examine the paper review process of major journals and share the findings from these studies with the rest of the research community members (Beyer et al., 1995; Cummings et al, 1985; Daft, 1995; Jauch and Wall, 1989; Murthy and Wiggins, 2002). Recognizing the urgent need to provide such type of information to MIS research community in Korea, we have chosen the most influential academic journal, APJIS with an intention to share the answer to the following research question: "What are the common problems found in the manuscripts either 'rejected' or 'required a major revision' by APJIS reviewers?" This study analyzes the review results of manuscripts submitted to APJIS (from January, 2006 to October, 2008), particularly those that were 'rejected' or required a 'major revision' at the first round. Based on Daft's(1995) study, twelve most-likelihood problems were defined and used to analyze the reviews. The twelve criteria for classification, or "twelve problems", are as follows: No theory, Concepts and operationalization not in alignment, Insufficient definition--theory, Insufficient rationale--design, Macrostructure--organization and flow, Amateur style and tone, Inadequate research design, Not relevant to the field, Overengineering, Conclusions not in alignment, Cutting up the data, and Poor editorial practice. Upon the approval of the editorial board of APJIS, the total 252 reviews, including 11 cases of 2005 and 241 cases from July, 2006 to October, 2008, were received without any information about manuscripts, authors, or reviewers. Eleven cases of 2005 were used in the pilot test because the data of 2005 were not in complete enumeration, and the 241 reviews (113 cases of 'rejection' and 128 ones of 'major revision') of 2006, 2007, and 2008 were examined in this study. Our findings show that insufficient rationale-design(20.25%), no theory(18.45%), and insufficient definition--theory(15.69%) were the three leading reasons of 'rejection' and 'major revision.' Between these two results, the former followed the same order of three major reasons as an overall analysis (insufficient rationale-design, no theory, and insufficient definition-theory), but the latter followed the order of insufficient rationale--design, insufficient definition--theory, and no theory. Using Daft's three major skills-- 'theory skills', 'design skills', and 'communication skills'-- twelve criteria were reclassified into 'theory problems', 'design problems', and 'communication problems' to derive more practical implications of our findings. Our findings show that 'theory problems' occupied 43.48%, 'design problems' were 30.86%, and 'communication problems' were 25.86%. In general, the APJIS reviewers weigh each of these three problem areas almost equally. Comparing to other disciplines like management field shown in Daft's study, the portion of 'design problems' and 'communication problems' are much higher in manuscripts submitted to the APJIS than in those of Administrative Science Quarterly and Academy of Management Journal even though 'theory problems' are the most predominant in both disciplines.

Characterization and breeding of a new cultivar Pleurotus ostreatus 'Heuksol' (느타리버섯 신품종 '흑솔'의 육성 및 특성)

  • Oh, Min-Ji;Im, Ji-Hoon;Shin, Pyung-Gyun;Oh, Youn-Lee;Jang, Kab-Yeul;Kon, Won-Sik
    • Journal of Mushroom
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    • v.15 no.3
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    • pp.129-133
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    • 2017
  • Oyster mushroom is a type of mushroom that is commonly cultivated and consumed in Korea. P. ostreatus 'Suhan' is a preferred cultivar for many mushroom farmers because it has a dark pileus and thick stipe. However, as it is very sensitive to environmental conditions, farmers consistently demand an alternative cultivar. To develop a new cultivar, the parental strains KMCC01680 ('Suhan') and KMCC00478 ('Gosol') were selected from various collected P. ostreatus strains by cultivating genetic resources. P. ostreatus 'Heuksol' was developed by the method of Mon-Mon crossing between monokaryotic strains derived from 'Suhan' and 'Gosol'. Thirty strains of 174 crossed strains were initially selected by cultivation experiments. After bulk cultivation tests, 'Heuksol' was selected. The nuclear DNA profile of 'Heuksol' was similar to those of the parental strains, 'Suhan' and 'Gosol', when RAPD (random amplified polymorphic DNA) primers and UPF (Universal PCR Fingerprinting) 2, 3, and 4 were used. The optimum temperature for mycelial growth was $30^{\circ}C$ for 'Heuksol', but medium-high temperatures were also appropriate, especially $13-20^{\circ}C$. The fruiting body production per bottle (1,100 mL) was approximately 140.8 g. When compared to the control strain 'Suhan', the thickness of the stipe of 'Heuksol' was greater than that of 'Suhan' (13.5 mm vs 9.4 mm). The pileus diameter of 'Heuksol' was similar to that of 'Suhan' and the pileus thickness of 'Heuksol' and 'Suhan' was 19.7 mm and 21.8 mm, respectively. 'Heuksol' had more a productive stipe number than 'Suhan' and the pileus of 'Heuksol' was dark gray, even at high temperatures. Therefore, it was suggested that this new cultivar, 'Heuksol', could provide an alternative to 'Suhan' and contribute to the profit of oyster mushroom farms.