• Title/Summary/Keyword: Effective size

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Effectiveness and Learning Experience of Dental Communication Course Training in Dental Hygiene Schools (치위생학과 교육과정에서의 치과의료커뮤니케이션 교과목 운영 사례연구)

  • Choi, Yong-Keum;Shin, Bo-Mi;Son, Jung-Hui;Park, Deok-Young
    • Journal of dental hygiene science
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    • v.16 no.2
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    • pp.134-141
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    • 2016
  • The purpose of this study was to develop a dental communication course in dental hygiene schools that included theory, practice, and skill for effective dental communication. Thirty-six senior dental hygiene students in a dental hygiene school took a dental communication course and responded to a questionnaire. The instrument used in the study was a modified form of Kim's communication skill self-assessment sheet. The self-assessment questionnaire about communication competencies was administered before and after the class, and the difference between scores at each time point was analyzed using the Wilcoxon signed rank sum test. Among seven elements of dental communication competencies, the competency of "information gathering" was significantly improved (p=0.008). Students' scores on perception of the importance (p=0.019) and necessity (0.016) of a communication course significantly increased after the course. Competencies in communication are essential requirement for dental hygienists. This study showed the possibility of communication skill training. An objective evaluation tool regarding students' communication competencies should be developed. Further studies with larger samples size are needed to develop a standardized comprehensive communication course in dental hygiene schools.

Analysis of Cloud Properties Related to Yeongdong Heavy Snow Using the MODIS Cloud Product (MODIS 구름 산출물을 이용한 영동대설 관련 구름 특성의 분석)

  • Ahn, Bo-Young;Cho, Kuh-Hee;Lee, Jeong-Soon;Lee, Kyu-Tae;Kwon, Tae-Yong
    • Korean Journal of Remote Sensing
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    • v.23 no.2
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    • pp.71-87
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    • 2007
  • In this study, 14 heavy snow events in Yeongdong area which are local phenomena are analyzed using MODIS cloud products provided from NASA/GSFC. The clouds of Yeongdong area at observed at specific time by MODIS are classified into A, B, C Types, based on the characteristic of cloud properties: cloud top temperature, cloud optical thickness, Effective Particle Radius, and Cloud Particle Phase. The analysis of relations between cloud properties and precipitation amount for each cloud type show that there are statistically significant correlations between Cloud Optical Thickness and precipitation amount for both A and B type and also significant correlation is found between Cloud Top Temperature and precipitation amount for A type. However, for C type there is not any significant correlations between cloud properties and precipitation amount. A-type clouds are mainly lower stratus clouds with small-size droplet, which may be formed under the low level cold advection derived synoptically in the East sea. B-type clouds are developed cumuliform clouds, which are closely related to the low pressure center developing over the East sea. On the other hand, C-type clouds are likely multi-layer clouds, which make satellite observation difficult due to covering of high clouds over low level clouds directly related with Yeongdong heavy snow. It is, therefore, concluded that MODIS cloud products may be useful except the multi-layer clouds for understanding the mechanism of heavy snow and estimating the precipitation amount from satellite data in the case of Yeongdong heavy snow.

Entrepreneurs' Competencies and Business Performance: A Meta-Analysis (창업가의 역량이 기업성과에 미치는 영향에 대한 메타분석)

  • Lee, Hye Young;Kim, Jin Soo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.14 no.5
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    • pp.13-24
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    • 2019
  • The purpose of this study is to provide a theoretical basis for future studies by systematically integrating existing empirical studies that examine the relationship between the entrepreneurs' competencies and business performance. As the results of empirical studies examining the relationship between the entrepreneurs' competencies and business performance are mixed, this study tries to derive different results from individual studies through meta-analysis into standardized statistics(effect sizes). To accomplish the purpose, this study developed hypotheses about the positive effects of the entrepreneurial competencies including opportunity recognition competency, managerial competency, technical-functional competency, strategic competency, and relationship competencies on the business performance through theoretical reviews of the literature. Also, this study conducted meta-analysis with 15 sample data using open source based statistical program 'R'. The results of this study are as follows. The opportunity recognition competency, managerial competency, technical-functional competency, strategic competency, and relationship competency were found to significantly affect financial business performance. Also, each of the factors had a moderate effect size on the performance. Among these competencies, the most effective factor was the strategic competency, followed by the opportunity recognition competency, technical-functional competency, and relationship competency. There is still no study using meta-analysis on the relationship between the entrepreneurs' competencies and business performance in South Korea. Therefore, the results of this study are expected to provide implications for developing the theoretical basis of future studies.

The Effects of Iron Powder Agglomeration on the Copper Removal Efficiency during Cementation Process for Treating Mine Drainages (광산배수 처리를 위한 세멘테이션 공정 중 구리제거효율에 대한 철분 응집의 영향)

  • Na, Hyunjin;Eom, Yuik;Hong, Seunggwan;Yoo, Kyoungkeun
    • Resources Recycling
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    • v.28 no.5
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    • pp.74-79
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    • 2019
  • The effects of equivalent of iron powder, particle size, agitation speed on the removal efficiency of copper ion were investigated by adding iron powder as cementation agents to simulated mine drainage solution with 117.15 mg/L Cu ion. The 50 % of Cu was removed at 90 min with 2 equivalent of iron powder while more than 99 % of Cu was removed at 60 min with 16 equivalent at 200 rpm and $20^{\circ}C$. The removal efficiencies of Cu ion were not different using 2 equivalent of $48{\mu}m$ and $150{\mu}m$ iron powder, and the removal efficiency increased rapidly with increasing the agitation speed to more than 400 rpm. This lower removal efficiency resulted from agglomeration of iron powder observed by SEM, which could reduce the effective specific surface area. More than 99 % of copper ion was removed using 2 equivalent of $48{\mu}m$ iron powder at 60 min, 600 rpm and $20^{\circ}C$.

Dietary Exposure to Transgenic Rice Expressing the Spider Silk Protein Fibroin Reduces Blood Glucose Levels in Diabetic Mice: The Potential Role of Insulin Receptor Substrate-1 Phosphorylation in Adipocytes

  • Park, Ji-Eun;Jeong, Yeon Jae;Park, Joon Beom;Kim, Hye Young;Yoo, Young Hyun;Lee, Kwang Sik;Yang, Won Tae;Kim, Doh Hoon;Kim, Jong-Min
    • Development and Reproduction
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    • v.23 no.3
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    • pp.223-229
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    • 2019
  • Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance (IR). T2DM is correlated with obesity and most T2DM medications have been developed for enhancing insulin sensitivity. Silk protein fibroin (SPF) from spiders has been suggested as an attractive biomaterial for medical purposes. We generated transgenic rice (TR) expressing SPF and fed it to diabetic $BKS.Cg-m+/+Lepr^{db}$ mice to monitor the changes in blood glucose levels and adipose tissue proteins associated with energy metabolism and insulin signaling. In the present study, the adipocyte size in abdominal fat in TR-SPF-fed mice was remarkably smaller than that of the control. Whereas the adenosine monophosphate-activated protein kinase (AMPK)-activated protein kinase and insulin receptor substrate 1 (IRS1) protein levels were increased in abdominal adipose tissues after TR-SPF feeding, levels of six-transmembrane protein of prostate 2 (STAMP2) proteins decreased. Phosphorylation of AMPK at threonine 172 and IRS1 at serine 307 and tyrosine 632 were both increased in adipose tissues from TR-SPF-fed mice. Increased expression and phosphorylation of IRS1 at both serine 307 and tyrosine 632 in adipose tissues indicated that adipocytes obtained from abdominal fat in TR-SPF-fed mice were more susceptible to insulin signaling than that of the control. STAMP2 protein levels decreased in adipose tissues from TR-SPF-fed mice, indicating that STAMP2 proteins were reducing adipocytes that were undergoing lipolysis. Taken together, this study showed that TR-SPF was effective in reducing blood glucose levels in diabetic mice and that concurrent lipolysis in abdominal adipocytes was associated with alterations of AMPK, IRS1, and STAMP2. Increased IRS1 expression and its phosphorylation by TR-SFP were considered to be particularly important in the induction of lipolysis in adipocytes, as well as in reducing blood glucose levels in this animal model.

The Effective Recovery of Gold from the Invisible Gold Concentrate Using Microwave-nitric Acid Leaching Method (마이크로웨이브-질산침출방법에 의한 비가시성 금의 회수율 향상)

  • Lee, Jong-Ju;Myung, Eun-Ji;Park, Cheon-Young
    • Journal of the Mineralogical Society of Korea
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    • v.32 no.3
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    • pp.185-200
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    • 2019
  • This study aimed to liberate gold from invisible gold concentrate (Au = 1,840.00 g/t) through microwave nitric acid leaching experiments. For the purpose, this study conducted microwave-nitric acid leaching experiments and examined nitric acid concentration effect, microwave leaching time effect and sample addition effect. The results of the experiments were as follows: Au (gold) contents were not detected in all of the microwave leaching conditions. In the insoluble-residue, weight loss rate tended to decrease as the nitric acid concentration, microwave leaching time and sample addition increased. In an XRD analysis with solid-residue, it was suggested that gypsum and anglesite were formed due to dissolution of calcite and galena by nitric acid solution. When a fire assay was carried out with insoluble-residue, it was discovered that gold contents of the solid-residue were 1.3 (Au = 2,464.70 g/t) and 28.8 (52,952.80 g/t) times more than those of concentrate. But in the gold contents recovered, a severe gold nugget effect appeared. It is expected that the gold nugget effect will decrease if a sampling method of concentrate is improved in the microwave-nitric acid leaching experiments and filtering paper with smaller pore size is used for leaching solution and burned filter paper is used for sampling in lead-fire assay.

Study on the Storage Stability of Horse Fat in Jeju (제주산 말지방(Horse Fat)의 저장 안정성 향상에 관한 연구)

  • Kim, Mi Seon;Yoon, Kyung-Sup
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.46 no.1
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    • pp.31-42
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    • 2020
  • Horse fat is known to be an effective ingredient in Asia, and the horse fat itself, which is mixed with other ingredients at the additive level, is often sold as a finished product. In this case, physical properties of the horse fat raw material are important. Many horse fats produced in Korea (Jeju) have low temperature stability, so if not stored at low temperatures, segregation may occur. In the case of Japanese horse fat, it is partially hydrogenated or is used the solid phase as the horse fat by separating the liquid phase and the solid phase that is harder and more stable than the horse fat of Jeju. In this study, the physical properties were tested to improve the temperature stability even without the partial hydrogenation process of Jeju horse fat. Various oil gelling agents were used in the study. Results confirmed that the physical properties of the hydroxystearic acid added Jeju horse fat were improved. In addition, stability evaluations at temperatures of 25 ℃, 40 ℃, 45 ℃ and flow behavior evaluations at temperatures of 25 ℃, 30 ℃, 40 ℃ were performed for Jeju horse fat with hydroxystearic acid, 100% Jeju horse fat, and 100% Japanese horse fat. Results showed that the Jeju horse fat improved in flow behavior by adding hydroxystearic acid similar to that of Japanese horse fat. In addition, when the crystal state was observed under a microscope, the thermal stability was improved by decreasing the size of the needle-type crystals with the addition of hydroxystearic acid. Jeju horse fat containing hydroxystearic acid was found to have no physical problems even when stored at room temperature for a long time.

Effect of Astragali Radix Pharmacocupuncture for Wound Healing of Full-Thickness Skin Wound in Mouse (황기약침이 전층피부손상 마우스의 치유에 미치는 영향)

  • Hong, Chang-Ho;Kang, Kyung-Hwa;Yoon, Hwa-Jung;Yoon, Hyoun-Min;Song, Choon-Ho;Kim, Cheol-Hong
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.31 no.1
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    • pp.22-31
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    • 2018
  • Objectives : In this study, we investigated whether Astragali Radix Pharmacocupuncture (ARP) has an effective on the full thickness defect wound healing process of mouse. Methods : A total of 50 mice (ICR mouse, 7 week-old male) were divided into control group and ARP group. A single full thickness skin defect was made on the dorsal side of the each mouse using an 8mm diameter biopsy punch. Control group were treated with 0.2㎖ saline and ARP group were treat with 0.2ml ARP at 8 points around the wound every three days total 4 times during the experimental period. The change in wound size, contraction rate, healing rate, and epithelization rate was measured by digital images taken on days 3, 6, 9, and 13, and evaluated using a digital image analysis program. Tissues were collected for histological analysis, RT-PCR, and Western blot on days 3, 6, 9, and 15. Results : The results are as follows. ARP group accelerated the rate of wound contraction, wound healing and epithelization compared to the control group. ARP group showed the decrease of inflammatory cells in early inflammatory phase compared to the control group. ARP group upregulated PECAM-1 mRNA and protein expression compared to the control group. ARP group inhibited the scar width and area compared to the control group. Conclusions: ARP showed positive effects on wound healing through the inhibition of inflammatory reaction and increase of PECAM-1 expression related to the wound healing process.

Biological Activity in Functional Cosmetic of Purple Sweet Potato Extracts (자색 고구마추출물의 기능성 화장품 활성)

  • Choi, Jae-Hong;Kim, Jin-Sung;Jo, Bun-Sung;Kim, Jeung-Hoan;Park, Hye-Jin;An, Bong-Jeun;Kim, Myung-Uk;Cho, Young-Je
    • Food Science and Preservation
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    • v.18 no.3
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    • pp.414-422
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    • 2011
  • The optimum condition for phenolics contents extraction from purple sweet potato was 12 hrs. in 50% ethanol. The electron donating scavenging activities (DPPH), ABTS radical cation decolorization (ABTS) and antioxidant protection factor (PF) of Jami, Yeonjami and Shinjami were higher than general sweet potato, and thiobarbituric acid reaction substance (TBARs) was below 30%. The minimum inhibitory concentration (MIC) against Staphylococcus aureus and Escherichia coli on skin were each 5,000 and 2,500 ppm in all purple sweet potatoes, and MIC of Jami was the lowest as 2,500 ppm against Staphlococcus epidermidis. The whitening (tyrosinase inhibitory) activity of purple sweet potatoes was the highest as 62.5% and 48.7% in Jami water and ethanol extracts. The anti-inflammation (hyaluronidase inhibitory) activity of purple sweet potatoes was the highest as 25.3% and 94.4% in Jami water and ethanol extracts. The safety of cosmetic with Jam; extracts was assessed by various safety profiles. pH and viscosity change of essence for 90 days was not detected. Cosmetic was stable to temperature and light for 90 days. The result to measure changes of skin color and pore size of the skin was that an aged skin was more effective than young skin.

Fabrication and Evaluation of Diameter 1 m Off-axis Parabolic mirror (직경 1 m 비축포물면의 가공 및 평가)

  • Yang, Ho-Soon;Lee, Jae-Hyeob;Jeon, Byung-Hyug;Lee, Yun-Woo;Lee, Kyoung-Muk;Choi, Se-Chol;Kim, Jong-Min
    • Korean Journal of Optics and Photonics
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    • v.19 no.4
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    • pp.287-293
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    • 2008
  • The collimator which makes a collimated beam, is an essential instrument for assembly and evaluation of telescopes. Recently, the Cassegrain type collimator has been widely used for its compact size as the focal length of high resolution cameras becomes longer. However, this kind of collimator has a disadvantage in that the secondary mirror is a heat source which can degrade the evaluation accuracy for an IR camera system. In this paper, we present the fabrication and measurement process for an off-axis parabolic mirror with the physical diameter pf 1 m, effective diameter 930 mm, and the focal length 6 m. After four months of works we obtained the final surface wave-front error of 30.4 nm rms ($\lambda$/138, ${\lambda}=4.2\;{\mu}m$), which is capable of evaluation of an IR camera as well as a visible camera.