• Journal of Pharmaceutical Investigation
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• 제25권1호
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• pp.1-7
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• 1995

After oral administration of various drinking solutions, the initial absorption rate of water through gastrointestinal tract of the rabbits was evaluated using tritinated water $(^3H_2O)$ as a marker to develop the sports drinking beverage for Korean people. The polynomial curve fitting over 20 min was performed using computer program to obtain the initial absorption rate of water from the tangent line of the fitted equation because initial absorption rate of water was more critical compared to elimination rate during exercise. The amount of water absorbed was increased but a large variation was observed among testing preparations in a small study group $(2{\leq}n{\leq}6)$. The initial absorption rate of water from isotonic sports drinking beverages was statistically significant when compared to hypertonic cola but was not significant when compared to hypotonic solutions (potable water and barley water). In case of hypertonic sports dringking beverages (i.e. Takeda), initial absorption rate of water was not improved and efficient when compared to other isotonic sports dringking beverages. The initial absorption rate of water from prescribed isotonic sample solution containing electrolytes, carbohydrates, and vitamins was not statistically significant when compared to other isotonic drinking beverages but showed similar absorption profile. It was obvious that isotonic solutions simultaneously containing electrolytes, vitamins and carbohydrates (sugar and glucose) had a tendency to increase the initial absorption of water compared to hypotonic (potable water and barley water) and hypertonic preparations (orange juice and cola). Although statistical significance of initial absorption rate of water between isotonic sports drinking beverages and hypotonic potable and barley water was not observed, unlike the hypertonic solutions, isotonic sports drinking beverages may aid not only to replenish loss of water, electrolytes and other nutrients during the exercise but also to prevent dehydration and muscle fatigue, resulting in improved physical performance in an exhausted condition.

• Restorative Dentistry and Endodontics
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• 제40권4호
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• pp.255-261
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• 2015

Objectives: The aim of this study was to evaluate the effect of three different drinks on the color parameters of four different restorative materials. Materials and Methods: Three different composites (Filtek Ultimate Universal Restorative, Filtek Ultimate Flowable, and Filtek Silorane, 3M ESPE) and a polyacid-modified composite resin material (Dyract XP, Dentsply DeTrey GmbH) were evaluated. Eighty-four disc-shaped specimens of 8 mm in diameter and 2 mm in thickness were prepared (n = 21 each). Color coordinates ($L^*a^*b^*$, ${\Delta}L^*$, ${\Delta}a^*$, ${\Delta}b^*$, and ${\Delta}E^*$) were measured using a $V{\dot{I}}TA$ Easyshade Compact ($V{\dot{I}}TA$ Zahnfabrik) after 24 hr of storage (baseline) and after 30 day of storage in three different beverages of black tea, Coca cola, or water (control) (n = 7). In each beverage, the specimens were stored three times a day, one hr each, for 30 day. The color changes (${\Delta}E$) were calculated and were analyzed by Kruskal-Wallis and Dunn multiple comparison test. Results: The color difference (${\Delta}E^*$) of the resin materials ranged between 1.31 and 15.28 after 30 day of immersion in the staining solutions. Dyract XP in Coca cola ($15.28{\pm}2.61$) and black tea ($12.22{\pm}2.73$) showed the highest mean ${\Delta}E^*$ value after 30 day, followed by Filtek Ultimate Universal Restorative ($5.99{\pm}1.25$) and Filtek Ultimate Flowable ($4.71{\pm}1.40$) in black tea (p < 0.05). Conclusions: The compomers displayed unacceptable color changes at the end of 30 day in all beverages. Among resin composites, the silorane based composite exhibited relatively good color stability than the others. Filtek Ultimate Universal Restorative and Filtek Flowable showed similar color changes in all beverages.

• 한국지구과학회지
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• 제25권8호
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• pp.674-683
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• 2004

과학연구를 하는 방법은 매우 다양하다. 과학영재아들로 하여금 본연의 과학연구능력을 개발하고 구현하도록 하는 목적을 달성한다는 것은 이미 알려진 영재교육의 목표이다. 여기서 과학연구능력이라고 할 때 과학연구의 요소는 무엇인가 살펴볼 필요가 생기며 하나의 과학연구가 존재하기 보다는 다양한 연구밥법이 공존한다는 입장이 더 설득력이 있다. 본 연구는 연구능력의 다양한 측면과 특성을 알아보는 탐색연구이며 더 세부적으로 들어가서 과학과정 능력 중 실험설계능력에 초점을 맞추었다. 물론 연구능력이라고 할 때에는 문제발견, 과학지식, 자아통찰 등 다양한 영역이 포함된다. 본 연구에서는 실험설계능력을 보기 위해 1990년 Fowler가 개발한 Diet Cola Test를 국내의 학생들이 사용할 수 있도록 번안하여 사용하였다. 전국 과학영재교육 프로그램에 참여하는 학생 중 총 705명의 초등학교 3학년에서 고등학교 1학년 학생들이 연구대상이 되었으며 과학교육분야에서의 문제중심학습과 창의적 사고력이라는 부분에 초점을 맞추어 연구자료를 해석하였다.

• 영재교육연구
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• 제16권1호
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• pp.43-60
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• 2006

과학영재교육의 사례를 살펴보는 것은 영재교육의 형성적 평가라는 차원에서 의미가 있다. 이에 본 연구에서는 학생들의 선발과정에서 얻어진 성취도검사자료, 구술시험, 창의력 검사, 문제해결능력검사 결과와 학생들이 입학후의 과학수행이 어떤 관계가 있는지를 알아보고자 했다. 과학영재 특히 지구과학반 7학년과 8학년을 대상으로 한 본 연구는 과학탐구의 기본적인 요소인 실험설계능력에 초점을 맞추었다. 실험설계능력으로 나타난 실제적인 과학 활동 수행의 결과가 선발과 어떤 관계를 갖는가를 알아봄으로써 과학영재프로그램의 재조명을 꾀하고자 하였다.

• 치위생과학회지
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• 제19권3호
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• pp.154-161
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• 2019

Background: The market for vitamin drinks is expanding both in Korea and worldwide. However, it was difficult to find studies regarding the possibility of tooth erosion induction due to vitamin drinks. The purpose of the present in vitro study was to evaluate the effect of tooth erosion caused by a few commercial vitamin beverages on bovine teeth enamel in terms of erosion depth and fluorescence loss. Methods: Three experimental groups (vitamin drinks), a positive control group (Coca-Cola), and a negative control group (mineral water) were established. Each group consisted of 5 specimens obtained from sound bovine teeth. The pH and titratable acidity of beverages were measured. Specimens were immersed in the beverages and artificial saliva for 6 and 18 hours, respectively. This cycle was repeated for 5 days. The depth of the tooth loss caused by tooth erosion (erosion depth) and maximum loss of fluorescence (Max ${\Delta}F$) were measured using the microscope and quantified light-induced fluorescence-digital, respectively. For the statistical analysis, the Kruskal-Wallis test and ANOVA were used to compare the erosion depth and Max ${\Delta}F$ of the enamel surfaces. In addition, Spearman correlations were estimated. Results: The pH of the three vitamin beverages ranged from 2.65 to 3.01, which is similar to that of the positive control group. All beverages, except mineral water, had sugar and acidic ingredients. Vitamin drinks and the positive control, Coca-Cola, caused tooth erosion lesions, and showed significant differences in erosion depth compared to mineral water (p<0.05). The vitamin beverages with low pH were associated with high erosion depth and Max ${\Delta}F$. Conclusion: Vitamin drinks have the potential to cause tooth erosion.

• 동아시아식생활학회지
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• 제13권1호
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• pp.1-8
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• 2003

The purpose of this study was to investigate the university students' recognition and preference of Korean rice cakes. Self administered questionnaires were collected from 302 students in Incheon area. Statistical data analysis was completed using a SPSS 10.0 program. The recognition of Korean rice cake was generally high: Injeolmi, Garaeddeok, Bakseolgi, Songpyun, Patsirooddeok, Bindaeddeok, Yaksik Julpyun, Gyungdan, Moojigaeddeok were high1y recognized, but Gaesungjooak, Sugyibyung, Seunggeomchopyun poorly recognized by university students. The most common consumption frequency rate of students was once or twice a month (Male 31.9%; Female 41.6%). Most students ate rice cakes as snack with water, Kimchi, fruits, beverage(Cola, Cider) and Korean traditional beverage(Sujunggwa, Sighye). The sales possibility of Korean rice cake at university canteens was dependent on the characteristics different from those of rice cafes itself, for example,. nutritional labelling, mass, atmosphere and package, etc.

• 한국포장학회지
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• 제15권3호
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• pp.105-111
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• 2009

In this work, source reduction of poly ethylene terephthalate (PET) packaging are discussed as aspect of sustainability, such as reuse, refill and recycling through the various treatment methods and historical studies for municipal solid waste (MSW) disposal. Since PET has good chemical, physical and mechanical properties, and provides good oxygen and carbon dioxide barrier properties, PET is one of the most widely used thermoplastic polyester in the U.S. and around the world. As the demand for non-renewable PET is increasing, several approaches have been developed to meet economical feasibility and environmental responsibility without degrading material performance. Several companies, such as Coca-Cola Co., Easterform Packaging Co. and Kraft, have tried to develop lightweight PET bottle, and some of lightweight PET bottles are already commercialized. Reuse and refilling for PET container is well developed in Europe, such as Denmark, German and Netherland by supportive legislation and policies. Recycling process is the best way to economically reduce PET waste. In consequence, advanced technique and further development must be provided due to increasing PET packaging waste.

• Journal of information and communication convergence engineering
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• 제10권4호
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• pp.349-358
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• 2012

Over a wireless sensor network (WSN), accurate localization of sensor nodes is an important factor in enhancing the association between location information and sensory data. There are many research works on the development of a localization algorithm over three-dimensional (3D) space. Recently, the complexity-reduced 3D trilateration localization approach (COLA), simplifying the 3D computational overhead to 2D trilateration, was proposed. The method provides proper accuracy of location, but it has a high computational cost. Considering practical applications over resource constrained devices, it is necessary to strike a balance between accuracy and computational cost. In this paper, we present a novel 3D localization method based on the received signal strength indicator (RSSI) values of four anchor nodes, which are deployed in the initial setup process. This method provides accurate location estimation results with a reduced computational cost and a smaller number of anchor nodes.

• 산업경영시스템학회지
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• 제22권50호
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• pp.313-322
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• 1999

EVA(Economic Value Added) is a management performance evaluation tool that determines whether a business is earning more than its true cost of capital. Leading corporations like Coca-Cola, AT&T and Briggs&Stratton have set up EVA measurement systems throughout their organizations. EVA reflects opportunity cost of equity ignored in calculating accounting profit and emphasizes the efficiency of capital employed by measuring how much the manufacturing and selling activities produce the economic profit in excess of cost of gross capital. In this paper, we define the concept of EVA and present an example to show the usefulness of EVA.

• 한국임상약학회지
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• 제3권1호
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• pp.21-30
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• 1993

The contents of caffeine in caffeine containing products in Korea, i.e., coffee. tea, cocoa and cola, and the individual pattern of consumption of caffeine containing beverages were studied to know the pattern of caffeine consumption. The correlation in between the amount of caffeine consumption and the obesity were also investigated. In results, the average contents of caffeine in the instant coffee was $31.8\pm4.4mg/g(mean{\pm}SD)$. The amount of caffeine in coffee were $68.2\pm13.0\;mg/cup$ in the vending machine coffee, and $76.6\pm12.1\;mg/cup$ in the coffee shop coffee. Average daily caffeine consumption per person was investigated to be 128mg with the wide range of 26mg-341mg. There was no correlation in the amount of daily caffeine consumption and the obesity.