• Journal of the Korean Chemical Society
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• v.39 no.12
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• pp.910-917
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• 1995

Analytical conditions for single column ion chromatographic determination of five anions such as F-, Cl-, NO2-, NO3-, and SO42- were optimized with respect to analysis time and separation efficiency. At the optimum condition of 2.0 mM phthalic acid at pH 4.5, five anions were effectively separated in 10 minutes so that analysis time could be reduced by 40% compared to other recommended conditions. Under this condition all the calibration curves of five anions were linear with a correlation coefficient > 0.999. Analytical results for nine commercial bottled waters were presented.

• Polymer(Korea)
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• v.29 no.1
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• pp.54-58
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• 2005

The hydrolytic behavior of microbial poly[(R)-3-hydroxybutyrate]](P(3HB)) has been studied by using two model systems, Langmuir monolayer and solution-grown single crystals (SCs), for elucidating the mechanism for both alkaline and enzymatic degradations. An initial degradation of SCs of P(3HB) leads to breakup lamellae parallel to their short axis (b-axis). Similarly, ridge formation on the lamellar surface appears along the b-axis at lower quenching temperature than melting temperature. Both results support that the lamellar crystals contain less-ordered and more thermally sensitive regions along the b-axis. Although the enzymatic hydrolysis of P(3HB) monolayers was similar to its alkaline one, the enzymatic degradation of P(3HB) monolayers occurred at higher constant surface pressure than the alkaline degradation. This behavior might be attributed to the size of enzymes which is much larger than that of alkaline ions; that is, the enzymes need larger contact area with monolayers to be activated.

• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.857-864
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• 2005

Dealuminated and alkali/alkaline-earth metal exchanged Y-type and ZSM-5 zeolites were prepared as catalytic materials. Comparing with the composition of starting material, the magnitude of Si/Al ratio was increased after dealumination and cation exchange process. The ratio of Si/Al on surface was appeared to be larger than that in bulk. The destruction of basic frame in catalysts observed was understood to be due to a detachment of aluminum, which results in reducing framework while increasing non-framework. This phenomenon becomes more serious with increasing time of steam treatment and even more significant for the cation exchanged catalysts. The desorption peaks of the NO-TPD profiles taken after dealumination and cation exchanged Y-type and ZSM-5 zeolites shifted to the low temperature region. It was also found that the longer the steam treatment time, the degree of shift toward low temperature region was increased. The catalytic activities are dependent on the nature of cation exchanged, the ratio of Si/Al and the ratio of framework/non-framework by a change in basic frame.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.109-116
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• 1996

The relationship between antioxidant activities and physicochemical properties of several fractions obtained from freeze-dried (FD) coffee were investigated. The nine kinds of fraction were consecutively extracted from FD coffee with solvents in increasing order of polarity, and the higher polarity of the solvent the higher extraction yield of the fraction. The antioxidant activities of the fractions were determined by Rancimat and oven test on edible oils. The antioxidant activities of the fractions increased in the order of acetone>ethanol>methanol>50% methanol/water>water fraction, and the antioxidant activities of them were higher on lard than on soybean oil. The antioxidant activity of each fraction was strongly related to the contents of total phenol, total nitrogen content and acidity, whereas color intensity, reducing power, carboxylic acid content showed little contribution to the activity. All fractions had three peaks maxima at 208, 275 and 324 nm on UV-visible spectra, but the only one at 324 nm was linealy proportional to the antioxidant activities of the fractions.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.5
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• pp.537-543
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• 2006

There have been many recent studies on the nonlinear rainfall-runoff modeling, where the use of neural networks is shown to be quite successful. Due to fundamental limitation of linear structures, employing linear models has often been considered inferior to the neural network approaches in this area. However, we believe that with an appropriate extension, the concept of linear impulse responses can be a viable tool since it enables us to understand underlying dynamics principles better. In this paper, we propose the use of multiple impulse responses for the problem of rainfall-runoff analysis. The proposed method is based on a simple and fixed strategy for switching among multiple linear impulse-response models, each of which satisfies the constraints of non-negativity and uni-modality. The computational analysis performed for a certain Korean hydrometeorologic data set showed that the proposed method can yield very meaningful results.

• Asian Journal of Turfgrass Science
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• v.20 no.2
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• pp.253-264
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• 2006

It is a general trend that golf courses have been developed on mountain areas or in valleys due to economical or legal reasons in Korea. Therefore, most of golf courses have special landscape characteristics of brooks and ridge lines as well as peaks. Development of golf courses in the regions of intermediate valley significantly influences ecological factors such as biodiversity, hydrology, and biogeochemical cycles due to changes in original ecosystems of valleys, ridges, and peaks. This study developed a comprehensive framework to incorporate ecological principles and examples into the landscape planning and design process. The restoration system fur water environment may significantly minimize the ecological impacts from developing golf courses. Biotops and artificial damps have been applied to a golf course construction site in southern part of Korea, requiring a restoration of existing water ecosystem by the local EPA. The detailed drawings and water restoration plans were presented in this paper.

• PNF and Movement
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• v.18 no.1
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• pp.107-116
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• 2020

Purpose: To investigate the effects of electromyography (EMG) biofeedback on the muscle activity of the trapezius, shoulder pain, function, and range of motion (ROM) in patients with subacromial impingement syndrome (SAIS). Methods: Sixteen patients (9 males and 7 females) with SAIS participated voluntarily. The main outcome measures were muscle activity of the trapezius, shoulder pain (VAS), ROM, and the shoulder pain and disability index (SPADI). Exercises with EMG biofeedback consisted of shoulder flexion in a standing position, shoulder external rotation in a side-lying position, and shoulder horizontal abduction in a prone position. Post measurements were taken immediately after EMG biofeedback training. Results: Middle and lower trapezius activity, as well as ROM, was significantly increased by exercise with EMG biofeedback (p<0.05). In addition, VAS and SPADI scores significantly decreased post-EMG biofeedback training (p<0.05). Conclusion: EMG biofeedback intervention is an effective exercise for SAIS patients to restore activity of the middle and lower trapezius and to improve pain, shoulder function, and ROM.

• Microbiology and Biotechnology Letters
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• v.47 no.1
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• pp.20-24
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• 2019

Moringa oleifera Lam (MOL) has been used as a traditional medicine to treat various cancers and inflammation. Whereas the bioactivities of the MOL leaf and seed are well reported, the study of the root is still rudimentary. In this study, the ethanol extract of MOL (EEMOL) and its subsequent organic solvent fractions were prepared and their anticoagulation activity in vitro and platelet aggregation inhibitory activity were evaluated. The EEMOL had negligible anticoagulation and strong platelet aggregation activities. However, the hexane and ethyl acetate fractions of EEMOL showed significant inhibition against thrombin, prothrombin, coagulation factors, and platelet aggregation, without hemolytic activity up to 1.0 mg/ml. Our results suggest that the active fractions of MOL root have potential as new anti-thrombosis agents.

• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.123-134
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• 2012

This work is to describe the geomorphological landscapes of of Dongcheon-gugok in Korea, and attempts to develop a basic data for traditional natural heritage. Dongcheon-gugok is a union of natural lanscape and human mind-activity. Therefore the study of natural landscape, which consists of geomorphological landscapes, provides a basic data for the use and conservation of traditional natural heritage. Dongcheon-gugok in Korea is almost distributed in the valley of mountainous areas of Taeback and Soback Mountain Ranges. The bedrocks of the areas of Dongcheon-gugok are almost granitic rocks and sedimentary rocks. The landscapes of Dongcheon-gugok is characterized by narrow meandering valley, so Gugok means nine-bended river. The elements of the geomorphological features is a broad flat rock with sheeting joints, joint-block seperated large blocks or tor, steep slope and rocky cliffs, pool, ripple, large or small scale waterfall, pot-hole, etc.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.28 no.3
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• pp.33-40
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• 2022

Background: The cross-body and the sleeper stretches have been used to improve posterior shoulder tightness (PST). However, such stretching techniques may not always help achieve scapular stability and may even aggravate patient's symptoms. Therefore, a new stretching technique (passive glenohumeral internal rotation with bridging) was developed as a more effective method that may allow for greater scapular stability without aggravating the symptoms. Thus, this study aimed to examine and compare this novel stretching technique to determine its effect on the range of motion (ROM) and acromio-humeral distance (AHD) in patients with glenohumeral internal rotation deficits (GIRD) with posterior shoulder tightness. Methods: A total of 30 symptomatic patients with asymmetrical GIRD were randomly assigned to two groups: the novel stretching group (n=15) and the joint mobilization group (n=15). The intervention was conducted twice a week for a total of four weeks. The ROM of shoulder internal rotation was measured by a goniometer and the AHD was evaluated by an X-ray before and after the intervention. Results: Both the treatments improved ROM and AHD in patients with GIRD (p<.05). However, the improvements in internal rotation ROM and AHD in the novel stretching group were significantly greater than that of the subjects in the mobilization group. There was a significant difference between the two groups (p<.05). Conclusion: These results show that both novel stretching and joint mobilization improved ROM and AHD in patients with GIRD with PST. However, novel stretching was more effective than joint mobilization.