• Journal of Mechanical Science and Technology
• /
• 제14권5호
• /
• pp.490-498
• /
• 2000

The authors have proposed methods (lead crowning and profile modification) for modifying the geometry of spur gears and investigated the contact pattern as well as the transmission errors to recommend the appropriate amount of modification. Based on the investigation, dynamic load of the modified spur gear drive has been calculated, which is helpful to predict the life of the designed gear drive. Computer programs for simulation of meshing, contact and dynamics of the modified spur gears have been developed. The developed theory is illustrated with numerical examples.

• Macromolecular Research
• /
• 제10권5호
• /
• pp.291-295
• /
• 2002

Atomic force microscopy(AFM) was used to study the polyethylene(PE) surfaces grafted and immobilized with acrylic acid by Ar plasma treatment. The topographical images and parameters including RMS roughness and Rp-v value provided an appropriate means to characterize the surfaces. The plasma grafting and immobilization method were a useful tool for the preparation of surfaces with carboxyl group. However, the plasma immobilization method turned out to have a limitation to use as a means of preparation of PE surface with specific functionalities, due to ablation effect during the Ar plasma treatment process.

• 한국염색가공학회지
• /
• 제13권4호
• /
• pp.256-263
• /
• 2001

Polyester fabrics were irradiated by UV produced by the low pressure mercury lamp. UV irradiation broke a C-H bond of PET fiber and caused the carbonyl groups on the fiber surfaces. Surface modification of PET fibers were accelerated by pretreatment with methanol, ethanol and acetone. The irradiated PET was dyed with basic dyes having cationic groups. The dye uptakes were proportional to irradiation times, and in inversely proportional to irradiation distances. The tensile strengths of PET fabrics decreased by UV irradiation. Washing fastness of PET dyeings were good, about 4-5 grade,andlightfastnesswerepoor, about l grade.

• 한국지진공학회:학술대회논문집
• /
• 한국지진공학회 2003년도 추계 학술발표회논문집
• /
• pp.231-238
• /
• 2003

The overstrength factor and the ductility factor are the two important factors that determines response modification factors used in current seismic codes. The objective of this paper is to obtain the overstrength and ductility factors of special concentric braced frames. For this purpose pushover analysis is performed with model structures until the maximum inter-story drift reaches 2.5% of story height. According to the analysis results, the overstrength factors increase as the height of structures decreases and the span length increases. Ductility factors for mid-story structures turns out to be higher than the other structures and span length does not contribute much to ductility factors.

• 한국식품영양과학회지
• /
• 제19권3호
• /
• pp.219-223
• /
• 1990

Myofibrillar protein from Alaska pollack was modified with acetic anhydride at pH 7.5 and $25^{\circ}C$ and changes in functional properties as affected by the degree of modification were determined. Acetylation of myofibrillar protein resulted in protein with unique functional properties dependent upon the degree of acetylation. By selecting appropriate degree of modification it was possible to control protein solubility heat coagulability calcium precipitability foaming and emulsion capa-city.

• 한국재료학회지
• /
• 제9권1호
• /
• pp.65-72
• /
• 1999

In order to minimize flexible printed circuit(FPC), which is used in computer, communication, medical facility, aviation space industry, it is required to improve the interfacial adhesion of polymide/epoxy or polyimide/polyimide consists of FPC. In this study, it was considered to improve the adhesion strength of polyimide/epoxy joint by introducing functional group on polyimide film and improving mechanical property of epoxy. Functional group on polyimide film was introduced by changing polyimide film surface to polyamic acid in KOH aqueous solution. The optimum conditions for surface modification were the concentration of 1M KOH and treatment time of 5min. Also, the optimum adhesion strength of polyimide/epoxy joint was obtained using rubber modified epoxy and polyamic acid as a base resin and curing agent of epoxy adhesive, respectively. The degree of surface modification of polyimide film examined with contact angle measurement of FTIR, thus modification of polyimide to polyamic acid was identified. Fracture surface of plymide/epoxy joint was analyzed by scanning electron microscopy, and modified polyamic acid reimidezed to polymide as increasing curing temperature.

• 대한간호학회지
• /
• 제36권5호
• /
• pp.751-760
• /
• 2006

Purpose: This study was to evaluate the effects of a comprehensive life style modification program on glycemic control and stress response in type 2 diabetes. Method: The participants(n=34) with type 2 diabetes were divided into either a usual care(control) or treatment(experimental) group. The experimental group(n=21) received a program that was based on a comprehensive life style modification protocol at a weekly meeting for 16 weeks. They also participated in individually prescribed exercise and diet along with stress management and self monitoring. The participants were followed for 6 months, during which postprandial glucose, HbA$_{1C]$, and stress response inventory were measured. Result: The experimental group showed a significant lower postprandial glucose and stress response compared to those of the control group. However, there was no significant change in the HbA$_{1C]$ value in either group. Conclusions: These results suggest that a type 2 diabetes comprehensive lifestyle modification program may lead to clinical improvement in glycemic control and reduce the stress response.

• Carbon letters
• /
• 제3권4호
• /
• pp.219-225
• /
• 2002

The two-step surface modifications of activated carbon was carried out to improve the adsorption capacity of toxic heavy metal ions in liquid phase. Physical and chemical properties of the as-received activated carbon (AC) and two kinds of surface-modified activated carbons ($1^{st}AC$ and $2^{nd}AC$) were evaluated through the BET analysis, surface acidity, and oxides measurements. Specific surface area and pore volume did not significantly change, but surface oxide-group remarkably increased by the surface modification. Equilibrium and batch adsorptions of the various metals, such as Pb, Cd, and Cr, using AC, $1^{st}AC$, and $2^{nd}AC$ were performed at initial pH 5. The adsorption capacity and rate of $2^{nd}AC$ were higher than those of AC and $1^{st}AC$. The carboxylic/sodium carboxylate complex groups were developed from the two-step surface modification of activated carbon, which strongly affected the adsorption of metal ions.

• 대한한의학원전학회지
• /
• 제22권3호
• /
• pp.1-6
• /
• 2009

"Byeonjeungbang-yakjeongjeon(辨證方藥正傳)" was written in the year of 1946 by Lee Sanghwa(李常和) by adding on the original "Bang-yakhappyeon(方藥合編)". 850 formulas based on experience from the times of old and present were added to the original 588 of "Bang-yakhappyeon" and Kimsamul(金四物)'s Samultang(四物湯) modification[加減], Yun Chochang(尹草窓)'s Ijintang(二陳湯) and Pyeong-wisan(平胃散) modification, Idongwon(李東垣)'s Bojung-ikgitang(補中益氣湯) modification, and Pung(馮)'s Yukmijihwangtang(六味地黃湯) modification were added. The 60 medical texts that he consulted greatly influenced the formulas that were added, and of those books the ones of interest include "Seoksilbirok(石室秘錄)", "Byeonjeungrok(辨證錄)", "Byeonjeunggimun(辨證奇聞)" and "Bucheongjunamnyeogwa(傅靑主男女科)". If we analyze the 850 formulas of "Byeonjeungbang-yakjeongjeon", 290 of them, 34%, are related to Jinsatak(陣士鐸)'s medical texts, and of those 290, 15 are from "Seoksilbirok"(5%), 49 are from "Bucheongjunyeogwa"(17%), and 226 are from "Byeonjeungrok"(78%). So, the added formulas of Leesanghwa's "Byeonjeungbang-yakjeongjeon" have been greatly influenced by Jinsatak(陳士鐸), and by looking through Jin(陳)'s medical ideas one can find the origin of prescriptions and become more flexible.

• 한국농공학회지
• /
• 제30권4호
• /
• pp.62-70
• /
• 1988

This study was conducted to solve the problems for the unsuitable parameters and the uncertainty of design flood can be appeared by low outliers were inclined to the lower part from the trend of the balance of the data. Derivation of reasonable design flood was attempted finally by modification of low outliers with analysis of flood frequency by means of Log Pearson Type Ill distribution. Three subwatersheds were selected as studying basins with the annual maximum series including low outliers along Geum River basin. The results through this study were analyzed and summarized as follows. 1. Log Pearson Type In distribution was confirmed as a reasonable one by X$^2$ goodness of fit test at Gong Ju, Gyu Am, og Cheon watershed along Geum River basin. 2. Probable flood flows for each watershed were derivated by flood frequency curve with outliers. 3. Weighted skew coefficient for each watershed was calculated for the evaluation of freq- uency factor which is needed for the modification of low outlier. 4. It was confirrned that adjusted frequency curve has a lower tendency than that of deletion of low outlier in common at all watersheds. 5. Final probable flood flows were derivated by modification with evaluation of modified basic statistics for three watersheds. 6. In comparison with a frequency curve with modification and one with outlier, The former has a higher probable flood flow within three years of return periods than that of the latter, and vice versa over three years of return periods.