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A Kinetic Study on the Hydration Process of Barley Kernels with Various Polishing Yields (도정수율별 보리의 수화공정(水和工程)에 관(關)한 속도론적(速度論的) 연구(硏究))

  • Mok, Chul-Kyoon;Lee, Hyun-Yu;Nam, Young-Jung;Min, Byong-Yong
    • Korean Journal of Food Science and Technology
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    • v.15 no.2
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    • pp.136-140
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    • 1983
  • The hydration characteristics of barley kernels with various polishing yields were investigated at temperatures of $20-60^{\circ}C$ and their sorption kinetics were studied. The moisture gain in initial stage of hydration was directly proportional to square root of hydration time and there was a break point at the moisture gain of 0.45-0.55g $H_2O/g$ solid. The hydration rate was great in order of polishing yield of 50, 70, 95, 90 and 100%, and increased with increasing hydration temperature. The diffusivity of water into barley kernels followed Arrhenius equation, and the activation energies in hydration reaction of polished barley were ranged from 6.9 to 9.5 Kcal/mole and that of non-polished one was 11.6Kcal/mole.

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Preference of undergraduate students after first experience on nickel-titanium endodontic instruments

  • Kwak, Sang Won;Cheung, Gary Shun-Pan;Ha, Jung-Hong;Kim, Sung Kyo;Lee, Hyojin;Kim, Hyeon-Cheol
    • Restorative Dentistry and Endodontics
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    • v.41 no.3
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    • pp.176-181
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    • 2016
  • Objectives: This study aimed to compare two nickel-titanium systems (rotary vs. reciprocating) for their acceptance by undergraduate students who experienced nickel-titanium (NiTi) instruments for the first time. Materials and Methods: Eighty-one sophomore dental students were first taught on manual root canal preparation with stainless-steel files. After that, they were instructed on the use of ProTaper Universal system (PTU, Dentsply Maillefer), then the WaveOne (WO, Dentsply Maillefer). They practiced with each system on 2 extracted molars, before using those files to shape the buccal or mesial canals of additional first molars. A questionnaire was completed after using each file system, seeking students' perception about 'Ease of use', 'Flexibility', 'Cutting-efficiency', 'Screwing-effect', 'Feeling-safety', and 'Instrumentation-time' of the NiTi files, relative to stainless-steel instrumentation, on a 5-point Likert-type scale. They were also requested to indicate their preference between the two systems. Data was compared between groups using t-test, and with Chi-square test for correlation of each perception value with the preferred choice (p = 0.05). Results: Among the 81 students, 55 indicated their preferred file system as WO and 22 as PTU. All scores were greater than 4 (better) for both systems, compared with stainless-steel files, except for 'Screwing-effect' for PTU. The scores for WO in the categories of 'Flexibility', 'Screwing-effect', and 'Feeling-safety' were significantly higher scores than those of PTU. A significant association between the 'Screwing-effect' and students' preference for WO was observed. Conclusions: Novice operators preferred nickel-titanium instruments to stainless-steel, and majority of them opted for reciprocating file instead of continuous rotating system.

Association of chairside salivary aMMP-8 findings with periodontal risk assessment parameters in patients receiving supportive periodontal therapy

  • Schmalz, Gerhard;Kummer, Max Kristian;Kottmann, Tanja;Rinke, Sven;Haak, Rainer;Krause, Felix;Schmidt, Jana;Ziebolz, Dirk
    • Journal of Periodontal and Implant Science
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    • v.48 no.4
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    • pp.251-260
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    • 2018
  • Purpose: The aim of this retrospective cross-sectional study was to evaluate whether salivary findings of active matrix-metalloproteinase 8 (aMMP-8) chairside (point of care; POC) tests were associated with periodontal risk assessment parameters in patients receiving supportive periodontal therapy (SPT). Methods: A total of 125 patients receiving regular SPT were included, and their records were examined. The following inclusion criteria were used: a diagnosis of chronic periodontitis, at least 1 non-surgical periodontal treatment (scaling and root planning) with following regular SPT (minimum once a year), at least 6 remaining teeth, and clinical and aMMP-8 findings that were obtained at the same appointment. In addition to anamnestic factors (e.g., smoking and diabetes), oral hygiene indices (modified sulcus bleeding index [mSBI] and approximal plaque index), periodontal probing depth simultaneously with bleeding on probing, and dental findings (number of decayed, missing, and filled teeth) were recorded. Salivary aMMP-8 levels were tested using a commercial POC test system (Periomarker, Hager & Werken, Duisburg, Germany). Statistical analysis was performed using the t-test, Mann-Whitney U test, Fisher's exact test, and ${\chi}^2$ test, as appropriate (P<0.05). Results: Only the mSBI was significantly associated with positive salivary aMMP-8 findings (aMMP-8 positive: $27.8%{\pm}20.9%$ vs. aMMP-8 negative: $18.0%{\pm}14.5%$; P=0.017). No significant associations were found between aMMP-8 and smoking, diabetes, periodontal parameters, or parameters related to the maintenance interval (P>0.05). Conclusions: Salivary aMMP-8 chairside findings were not associated with common parameters used for periodontal risk assessment in patients receiving SPT. The diagnostic benefit of POC salivary aMMP-8 testing in risk assessment and maintenance interval adjustment during SPT remains unclear.

MICRODONTIA IN A CHILD TREATED WITH CHEMOTHERAPEUTIC AGENT (항암 화학치료를 받은 아동의 치아발육이상 : 증례 보고)

  • Kye, Hi-Ran;Lee, Jae-Ho;Kim, Seong-Oh;Sohn, Heung-Kyu
    • Journal of the korean academy of Pediatric Dentistry
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    • v.26 no.1
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    • pp.146-150
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    • 1999
  • With the improved cure rates for childhood malignant conditions in the past decade, late effects of cancer therapy must be recognized to minimize their impact on the quality of life in long-term survivors. Chemoradiation therapy is a major part of pediatric oncology treatment and is implicated in causing tooth agenesis, microdontia, root shortening, early apical closure, and coronal hypocalcification. Dental development may be affected by illness, trauma, chemotherapy, or radiation therapy at any point prior to complete maturation. Treatment given during the first 3.5 years of life was more likely to affect the dental lamina and crown formation and result in a small tooth. Dental treatment affected by chemoradiation damage to developing teeth includes orthodontic tooth movement, prosthetic abutment consideration, periodontal health, space maintenance, requirement for home fluoride regimens to protect hypomineralized teeth, and enodontic procedures. Dental abnormalities are common in patients treated for cancer, and these children require aggressive dental follow-up. Meticulous surveillance may facilitate detection of abnormalities, enabling the dental practitioner to intervene earlier in promoting a more aggressive regimen of oral care, thus reducing the morbidity associated with dental sequelae of oncotherapy, specifically periodontal disease and malocclusion. In this case, we report microdontia of all permanent second premolar and second molar in an 8 year old boy treated with chemotherapeutic agents during period of active dental development(14 months to 38 months of age).

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Parameter Estimation of Intensity-Duration-Frequency Formula Using Genetic Algorithm(II): Separation of Short and Long Durations (유전자알고리즘을 이용한 강우강도식 매개변수 추정에 관한 연구(II): 장.단기간 구분 방법의 제시)

  • Shin, Ju-Young;Kim, Tae-Son;Kim, Soo-Young;Heo, Jun-Haeng
    • Journal of Korea Water Resources Association
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    • v.40 no.10
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    • pp.823-832
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    • 2007
  • In this study, the separation of short and long durations for estimation the parameters of IDF curve is suggested by using Multi-Objective Genetic Algorithm (MOGA). Objective functions are to minimize root mean squared error (RMSE) and relative RMSE between observed and computed values. The criteria for separation are two; the first one is to estimate more precisely the parameters of IDF curve and the second is to make a single IDF curve without non-continuous duration point. For this purpose 22 rainfall recording gauges operated by Korea Meteorological Administration are selected and three IDF curves that are used generally in South Korea are tested. The result shows that the IDF curve developed by Heo et al. (1999) would be the best of three tested IDF curves, and the suggested parameter estimation method using MOGA can compute more reliable parameters compared with empirical regression analysis.

A Study on the Feminism in Contemporary Fashion Design (현대패션에 표현된 페미니즘에 관한 연구)

  • 금기숙
    • Journal of the Korean Society of Costume
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    • v.30
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    • pp.211-225
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    • 1996
  • In this paper we discuss the corelation be-tween feminism and fashion and examine its influnce on mordern fashion. And we also try to infer what the fashion design will be like in the future by understanding the value of modern fashion from a new viewpoint. The Early Feminism which advocated the similarity between man and women held the thought that women could be equal to men only when they behaved in the same way as men did, In 1970s when the pendulum of the Early Feminism movement reached its highest point a manish look began to flourish. The manish look introduced the items once employed only for men such as trench costs tidy tailored suits shirts and ties to women clothes. It has taken root deeply in women's life and is still employed in various ways by many designers. From the late 1970s the pendulum of feminism movement began to swing toward the Essentialist Feminism which emphasized the differences between men and women. It focused not on the negative image of women seen from male-oriented viewpoints but on their positive image and stressed women's sexual characteristic to make distinction between two genders. in fashion the Essentialist Feminism played a role in bringing about a sexy look which stressed the erotic silhouette of woman's body. The latest feminism is the socio-cultural one. It sees the distinction between men and women as sexual discrimination and introduces the androgynous human which carries the characteristic of two sexes. it leads to ambiguity of sex roles and at the same time serves to make androgynous social atmosphere by admitting the coexistence of two genders. The androgynous idea in fashion is expressed as a new trend which crosses men and women's own beauty while keeping their own identity intact. As we have briefly reviewed feminism in fashion has been presented in various ways with regard to expressing the nature of men and women. And it has continuously indicated the ultimate message of the salvation of mankind such as the respect for humanity and recovery of humanism.

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심근조영심초음파에서 심장의 움직임을 보정한 비침습적 심근관류모델의 정량적 평가

  • 이재훈;김희중;정남식;임세중;김기황
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2003.09a
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    • pp.49-49
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    • 2003
  • 목적 : 심초음파는 비침습적이므로 반복적으로 정확히 심질환의 경과를 관찰하여 치료효과 및 수술시기를 정할 수 있는 검사로서 임상적으로 매우 유용하다. 실시간 심근조영심초음파에 의한 time intensity 평가는 부위별로 수행됨으로 연속적으로 위치하는 관심영역이 intensity에 있어 심장의 움직임 변화에 영향을 받는다. Time intensity 곡선의 최적의 곡선맞춤을 위해 주기적인 심장 운동 매개변수를 조합해 기존의 모델을 보정한 안정적인 측정방법을 제시한다. 방법 : 심장의 운동에 의한 특징적인 정보를 설명하기 위해 기존의 문헌에 제시된 지수 함수에 주어진 심박수로 만들어진 시간에 관한 일반적인 정형파 함수를 추가한다. C(t) = A[1 - exp($\beta$t)] + Dsine(2$\pi$ft + $\theta$) C(t): videointensity A: plateau videointensity (blood volume) $\beta$: capillary blood velocity (rate constant of rise in videointensity) t: pulsing interval (ms) D: displacement from the periodic variance of the curve (estimated motion field from the ejection point for the ratio between systole and diastole) f: heart rate $\theta$: transit time issue A $\times$ $\beta$ : myocardial blood flow 관상동맥의 관류 데이터에 대한 실험이 펄스간격에 대한 비디오 세기로 수행되었다. 그리고 이러한 결과들이 the sum of squares due to error, R square, root mean squared error로 평가되었다. 결과 : 실험결과, 주기적인 심장의 움직임과 심박출 시점으로부터의 변위를 잘 기술하고 곡선에서의 측정 점들이 예측된 심장 움직임에 따라 성공적으로 표시되었다. 뿐만 아니라 보정된 모델이 현저한 적합도의 향상을 보여주었다. 결론 : 제시된 접근방법은 각각의 측정에서 심장 운동 영역의 변화에 독립적이며 측정 시점에 의해 영향받지 않고 심근 관류의 안정적인 측정이 가능하다. 심장의 움직임에 관한 매개변수를 조합한 모델로 곡선접합을 수행함으로써 관류의 정량적 정보를 좀더 정확하게 얻을 수 있으며 임상적 이용을 가능하게 할 것으로 기대된다.

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Coulometric Titration for the Determination of Nonstoichiometry in Ni1-XO (전하량적정법에 의한 Ni1-XO의 Nonstoichiometry 측정)

  • Suh, Sang-hyuk;Oh, Seung-Mo
    • Applied Chemistry for Engineering
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    • v.2 no.4
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    • pp.385-392
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    • 1991
  • Nonstoichiometry and defect model for $Ni_{1-x}O$ were determined by coulometric titration method. In the temperature range of 1123-1198K and oxygen partial pressure of 0.21-0.1 atm, the nonstoichiometry was found to be proportional to the fourth root of the oxygen partial pressure. This pressure dependence can be explained by the fact that nonstoichiometric $Ni_{1-x}O$ contains singly ionized metal vacancies as the predominant point defects. At T=1173K and $Po_2=0.21atm$, the nonstoichiometry, x was $1.21{\times}10^{-4}$. The standard formation enthalpy of defects in $Ni_{1-x}O$ was found, on the basis of this defect model, to be 0.95 eV. Also the result indicates that both of singly and doubly ionized metal vacancies are simultaneously present at above 1248K.

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3D Geopositioning Accuracy Assessment Using KOMPSAT-2 RPC (KOMPSAT-2 RPC를 이용한 3차원 위치결정 정확도 분석)

  • Oh, Kwan-Young;Jung, Hyung-Sup;Lee, Won-Jin;Lee, Dong-Taek
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.29 no.1
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    • pp.1-9
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    • 2011
  • The objective of this paper is to improve the accuracy of the 3D geopositioning extracted from Rational Polynomial Coefficient(RPC) provide in the KOMPSAT-2 metadata files. In this paper, we developed the algorithm to adjust a RFM(Rational Functional Model), and could improve the accuracy of a RFM with this algorithm. Furthermore, when a RFM was adjusted with this algorithm, the effects of the number of GCPs on the accuracy of the adjusted RFM was tested. For accuracy assessment using adjusted RFM, 9 ground control points(GCPs) and 24 check points could be used. Results indicated that the root mean squared errors(RMSEs) of horizontal residual errors calculated 24 check points were 2.20(m). The achieved accuracy of three dimensional object-point determination was 1.72(m) in the X-dimension and 1.37(m) in the Y-dimension and 2.20(m) in the Z-dimension.

Effects of Menstrual Cycle Phase on Knee Muscle Activity during One Leg Landing in Non-athletic Females

  • Lee, Ji-Min;Shin, Won-Seob
    • The Journal of Korean Physical Therapy
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    • v.28 no.5
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    • pp.308-313
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    • 2016
  • Purpose: This study investigated the effects of sex hormones across menstrual cycle phases on knee muscle activity during one-leg landing in non-athletic females. Methods: Twenty-six healthy females who reported normal menstrual cycles for the previous three months were tested when estrogen levels were highest (ovulation) and lowest (menstruation). Knee muscle activity was analyzed based on electromyography (EMG) data recorded during landing on a 30-cm box. Before data collection, each subject was trained in single-leg landing tasks ten times. Landing was analyzed by measuring the average of three landing tasks. EMG data were collected between the moment of ground contact and the point of knee maximum flexion. The maximum voluntary isometric contraction (MVIC) for normalization that was recorded as the EMG root-mean-square (RMS) during landing was tested, with paired t-tests used to assess differences in knee muscle activity according to menstrual cycle phases. Results: The results showed that the soleus, semitendinosus, and lateral gastrocnemius muscle activity during landing was differed significantly during ovulation compared to that during menstruation (p<0.05). No significant differences in vastus medialis activity were found between menstrual and ovulatory phases during landing (p>0.05). Conclusion: Changes in the menstrual cycle in response to sex hormones changed the activity of muscles around the knee during landing. Females utilize different muscle activity control strategies during different phases of the menstrual cycle, which may contribute to increased ACL injury risk.