• Journal of Korean Society of Environmental Engineers
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• v.28 no.8
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• pp.866-871
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• 2006

The nutrient recovery in phosphate crystallization process was investigated by using laboratory scale uptlow reactors, adopting sequencing batch type configuration. The industrial waste lime was used as potential cation source with magnesium salt($MgCl_2$) as control. The research was focused on its successful application in a novel integrated sludge treatment process, which is comprised of a high performance fermenter followed by a crystallization reactor. In the struvite precipitation test using synthetic wastewater first, which has the similar characteristics with the real fermentation effluent, the considerable nutrient removal(about 60%) in both ammonia and phosphate was observed within $0.5{\sim}1$ hr of retention time. The results also revealed that a minor amount(<5%) of ammonia stripping naturally occurred due to the alkaline(pH 9) characteristic in feed substrate. Stripping of $CO_2$ by air did not increase the struvite precipitation rate but it led to increased ammonia removal. In the second experiment using the fermentation effluent, the optimal dosage of magnesium salt for struvite precipitation was 0.86 g Mg $g^{-1}$ P, similar to the mass ratio of the struvite. The optimal dosage of waste lime was 0.3 g $L^{-1}$, resulting in 80% of $NH_4-N$ and 41% of $PO_4-P$ removal, at about 3 hrs of retention time. In the microscopic analysis, amorphous crystals were mainly observed in the settled solids with waste lime but prism-like crystals were observed with magnesium salt. Based on mass balance analysis for an integrated sludge treatment process(fermenter followed by crystallization reactor) for full-scale application(treatment capacity Q=158,880 $m^3\;d^{-1}$), nutrient recycle loading from the crystallization reactor effluent to the main liquid stream would be significantly reduced(0.13 g N and 0.19 g P per $m^3$ of wastewater, respectively). The results of the experiment reveal therefore that the reuse of waste lime, already an industrial waste, in a nutrient recovery system has various advantages such as higher economical benefits and sustainable treatment of the industrial waste.

• Restorative Dentistry and Endodontics
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• v.33 no.2
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• pp.107-114
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• 2008

This study was performed to assess the radiopacity of a variety of canal filling and retrograde root-end filling materials according to the specification concerning root canal obturation materials. Ten materials including Gutta-percha pellets, amalgam, Fuji II LC, $Dyract^{(R)}$ AP, Super $EBA^{(R)}$, $IRM^{(R)}$, AH $26^{(R)}$, $Sealapex^{TM}$, Tubli-$Seal^{TM}$, and dentin were evaluated in this study. In the first part, densitometric reading of an each step of aluminum step wedge on occlusal film were performed at 60 kVp (0.2, 0.3, 0.4 s), 70 kVp (0.2, 0.3, 0.33 s) to decide appropriate voltage and exposure time. In the second part, ten specimens which are 5 mm in diameter and 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 mm in thickness, were fabricated from each material studied. The specimens were radiographed simultaneously with an aluminum step wedge under decided condition (60 kVp, 0.2 s). The mean radiographic density values of the materials were transformed into radiopacity expressed equivalent thickness of aluminum (mm Al). The following results were obtained. 1. Among the various conditions including 0.2 s, 0.3 s, 0.4 s at 60 kVp and 0.2 s, 0.3 s, 0.33 s at 70 kVp, the appropriate voltage and exposure time that meet the requirement of density from 0.5 to 2.0 was 0.2 s at 60 kVp. 2. All of the materials in this study had greater radiopacity than the minimun level recommended by ISO No. 4049 standards. 3. Most of the materials had greater radiopacity than 3 mm Al requirement of ANSI/ADA specification No. 57 (2000) and ISO No. 6876 (2001) standards except for Fuji II LC and Dyract. It suggests that all experimental canal filling and retrograde root-end filling materials have a sufficient radiopacity that meet the requirement concerning root canal obturation materials except for Fuji II LC and Dyract.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.114-120
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• 1985

This study was conducted to investigate the important weeds occurring in onion and garlic planted in paddy field as the succeeding crop of rice and to evaluate the effect of competition between these crops and weeds on the yield of onion and garlic. In terms of quantity occurred, Persicaria hydropiper, Chenopodium ficifolium, Alopecurus aequalis, Poligonum aviculare, Echinochloa crus-galli, and Bothrisospermum tenellum appeared to be the major weeds in onion and garlic fields. Annual broadleaves were composed of 90.0 and 94.3% of total weed dry weight in onion and in garlic fields, respectively. Among these weeds, P. hydropiper was the most dominant species in onion and C. ficifolium in garlic fields. The higher Simpson's index such as 0.67 in garlic as compared to 0.40 in onion can be attributed to the presence of a C. ficifolium, which is existed in a single dominant species. The full season competition between the crops and these weeds resulted in yield reduction of onion by 23.9% and garlic by 31.9%, showing weed dry weight, 448.18 and 418.40 g/$m^2$ in onion and garlic fields, respectively. The maintenance of weed free condition for about 4 weeks after weed emergence could be the prerequisite to obtain the maximum yield of these two crops.

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.9-18
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• 2013

The aim of this study is to provide the basic data for yacon [Samallanthus sonchifolius (Poepp. & Endl.) H. Robinson] in dietary food. The nutritional compositons, such as protein, ash, carbohydrate, dietary fiber, vitamin and fructooligosaccharide, were analyzed for 4 yacon germplasm lines. Yacon has low calories with only 46~56 kcal/100 g. The contents of water, fat, ash, protein, carbohydrate and dietary fiber were ranged 85.9~86.8%, 0.1~0.2%, 0.2~0.3%, 0.5~0.7%, 12.2~13.1% and 1.05~1.14%, respectively. The iodine-starch test did not show any color or precipitation reaction, which indicates that yacon has no starch content. However, in the absence of starch, yacon is rich in fluctooligosaccharide, which is between 9.6~11.1%. Maltose is present in the larger amount, followed by sucrose, glucose, and fructose in terms of free sugars. The analysis of minerals revealed that yacon contains potassium in the larger amount of 141~176 mg/100 g F.W., followed by magnesium at 8.2~10.6 mg, calcium, and sodium representing the least present mineral. Yacon proved to have a total of 17 types of amino acids, which are between 404.0~581.8 mg per 100 g of yacon. Glutamic acid, the main sweetening component, is present in the large amount of 94.0~182.2 mg/100 g F.W., followed by aspartic acid, arginine, and alanine. The proportion of the essential amino acid was 24.8~33.6%. Results of analysis also showed that yacon contains 0.001~0.024 mg, 0.03~0.11 mg, 0.02~0.3 mg, 0.3~0.4 mg and 14.1~20.6 mg of ${\beta}$-carotene, thiamin, riboflavin, niacin, and ascorbic acid, respectively. It is also likely to be highly used as functional food material in the future because it is abundant in both fluctooligosaccharide and antioxidants which are important functional components.

• Journal of agricultural medicine and community health
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• v.42 no.4
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• pp.234-243
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• 2017

Objective: This study was aimed to evaluate the effectiveness of the diabetes education program implemented in a community hypertension and diabetes education center. Methods: Participants were thirty nine diabetic patients who received the education program in the center from May 2014 through May 2015. The education program consisted of two sessions for 2 days (45 minutes per session) regarding clinical information, nutrition and exercise for type 2 diabetes patients. Initially, they were assessed for general characteristics, knowledge on diabetes, self-efficacy and self-care behaviors. Reassessment was performed on their knowledge and self-efficacy directly after the program, and on self-care behaviors at 12 weeks after the program. Results: The mean score of diabetes knowledge was significantly increased from $5.27{\pm}2.10$ to $8.21{\pm}1.20$ (p<0.001) between before and after the program. The self-efficacy score was also significantly increased from $6.88{\pm}1.72$ to $8.16{\pm}1.47$ (p<0.001). The self-care behavior score was significantly increased from $3.59{\pm}1.89$ before the program to $4.35{\pm}1.29$ (p<0.001) at 12 weeks after the program. Conclusion: The diabetes education program may be effective on the improvement of knowledge, self-efficacy and self-care behaviors in type 2 diabetic patients.

• The Korean Journal of Air & Space Law and Policy
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• v.31 no.2
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• pp.177-214
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• 2016

During more than 20 years of practice, Civil Aviation Law has experienced three times of amendments since it was enacted in 1995. But these revisions are limited to the technical level. The problems and limitations have become increasingly prominent in its implementation. Firstly, the civil aviation law is the result of interests game among several departments and some legal issues was left behind and the regulation was very vague as a result. Secondly, the process of aviation legislation is the process that the country has undergone profound changes and social transformation. The 20 years is long enough for the society to undergo tremendous changes and 1995 version of civil aviation law does not keep pace of development of economy. There was a serious lag between reality and the law. In order to actively promote the development of the aviation industry and overcome implementation issues of the Civil Aviation Law, Civil Aviation Administration of China (CAAC) initiated modification procedure the law and published new draft of Civil Aviation Law in August 2016. The spirit of this modification is to learn and absorb new achievements of domestic and foreign legislation and the International Convention on civil aviation. Furthermore, the purpose of the revision is to provide favorable policy for the development of civil aviation industry and improve aviation safety and supervision, strengthen and protection of consumer rights and interests, to enhance the safety of civil aviation activities, and promote the development of general aviation. This revision concerned to the 78 articles which are revised or deleted and 24 articles added. The highlights of the draft include but not limited to the enhancement of security management, clarification of the main responsibility for production safety. And also it added the provisions related to the construction of effective tracking capability of public air transport enterprises and license system on the transport of dangerous goods. Compared with the existing civil aviation law, the draft has made a great improvements. But there are several deficiencies and limitations in the drafts. These problems need to be supplemented and perfected through further amendments in near future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.548-553
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• 2010

This study was carried out to compare the physicochemical characteristics of Korean traditional wines fermented by addition of sorghum (Sorghum bicolor) using different nuruks (SH and BS nuruk). The alcohol contents of the fermented wines ranged from 12.36 to 13.21%. The brix degrees of sorghum wines fermented using SH and BS nuruks were $8.6\sim17.9^{\circ}Bx$ and $7.6\sim20.0^{\circ}Bx$ on addition ratio, respectively. Wine no addedsorghum using SH and BS nuruks showed pH 3.74 and 3.40, total acidity of 1.40 and 1.51%, and 0.441 and 0.149 of turbidity. With increase of sorghum addition, brix degree, pH, turbidity and L-value decreased whereas total acidity and a-value increased. Total color difference (${\Delta}Eab$) parameters of wines fermented in 30, 70 and 100% sorghum addition using SH and BS nuruk were 4.33, 6.63 and 26.13, and 4.08, 5.29 and 10.59. Glucose content decreased with increasing amounts of sorghum. Organic acids such as lactic acid and acetic acid were predominantly detected in the fermented wine. Finally, based on sensory evaluations, the wine fermented by BS nuruk showed the best overall quality at 30% sorghum addition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1369-1379
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• 2014

The physicochemical characteristics and antioxidant activities of leaf, stem, and root of ginger (Zingiber officinale R.) were determined. Nutrient composition, reducing sugar, saponin, mineral, heavy metal, total phenolic and total flavonoid contents, and antioxidant activities based on DPPH radical scavenging and FRAP assay were measured. Catechins, gingerols, shogaols, and capsaicin compositions were also determined by HPLC. The contents of water, proteins, fats, carbohydrates, fiber, and ash from ginger root were 6.4, 6.8, 3.2, 65.4, 7.3, and 18.2%, respectively. Crude fiber contents of leaf and stem were 4~5 times higher than those of root (P<0.05), and reducing sugar content of stem was about 3 times higher than those of root. Crude saponin contents were in the order of stem

• Korean Journal of Childcare and Education
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• v.5 no.2
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• pp.21-42
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• 2009

The purpose of this study was to examine the effects of reading and discussion activities on children's self-esteem in a social welfare center called 'Gongbubang.' A reading/discussion program was constructed to serve the purpose of the study and suit the selected children by referring to earlier studies that found reading programs were effective at boosting the self-esteem of elementary schoolers. The subjects in this study were 21 children in 'HaedamGongbubang', a general social welfare center located in an urban region in South Gyeongsang Province. Out of them, 12 children who involved four boys and eight girls were selected as an experimental group, and nine who included five boys and four girls were grouped into a control group. The reading/discussion program was implemented in eight sessions during a four-week period of time from September 23 to October 15, 2009, twice a week, 50 to 55 minutes each. The instrument used in this study was Yoon Hyang-mi(2008)'s Self-Esteem Inventory, and the collected data were analyzed with a SPSS 12.0 program. The major findings of the study were as follows: First, the reading and discussion activities had an effect on bolstering the general self, social self and academic self of the children in the Gongbubang, a social welfare center. Second, the reading and discussion activities were effective at improving the general self and academic self of the school boys in the Gongbubang, a social welfare center. Third, the reading and discussion activities had an effect on fostering the social self and academic self of the school girls in the Gongbubang, a social welfare center. The findings of the study illustrated that the reading and discussion activities had an effect on furthering the self-esteem of the children in the Gongbubang, a social welfare center, and those activities are expected to be conducive to the self-esteem of children in Gongbubangs, which are social welfare centers.

• Journal of The Korean Association For Science Education
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• v.38 no.2
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• pp.259-271
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• 2018

This study examined the effect of the SSI argumentation program based on social and emotional learning(SEL). The program consisted of 3 stages: (1) express their own feelings about SSI, identify the issues of SSI, and define a goal; (2) think of many possible solutions and envision results through argumentation; (3) select the best solution and make a decision based on warrants, data, and rebuttals. In each stage, the social-emotional strategies of self-awareness, self-management, social-awareness, relationship-management, and responsible decision making were used. Seventeen preservice biology teachers participated in this study during one semester dealing with four socioscientific issues. The results indicated that the preservice teachers, as time went on, became accustomed to expressing identifiable rebuttals, dispute talk, and asking questions. At the first SSI argumentation, argumentation mainly consisted of cumulative talk with no rebuttals, representing level 2 argumentation. Level 3 argumentation represented rebuttals that were implicit and weak, with cumulative talk. In level 2 and 3 argumentation, the preservice teachers represented understanding of others and compassion for self and others. Level 4 argumentation had rebuttals that were explicit, asking critical questions of the opposite sides. In addition, level 5 argumentation represented more than two controversial points with several instances of dispute talk. In levels 4 and 5, the preservice teachers became actively engaged in communication, inquiry self with others, managing vulnerability and negotiation.