컵(Cup) 색에 따른 기본 맛과 커피의 관능특성 인지 연구

차성수,조윤주,윤혜현,Cha, Sung Soo,Jo, Yun Ju,Yoon, Hye Hyun 한국식품조리과학회 2018 한국식품조리과학회지 Vol.34 No.3

Purpose: The study was conducted to investigate the basic taste and the sensory properties of coffee according to cup color. Methods: Attribute difference tests were performed for basic taste solution and coffee samples in six different colored paper cups by 68 trained panelists. In addition, a check-all-that-apply (CATA) was conducted to evaluate flavor characteristics of coffee samples. Results: Based on the basic taste test, the scores of sweetness and saltiness were higher for samples in red and orange cups than those in other colored cups. while the highest bitterness score was observed in black cups. Moreover, sweetness of coffee was stronger in red cups, while sourness was highest in yellow and green cups. Bitterness, opacity, concentration and body of coffee in black cups were stronger than those of coffee samples in other colored cups, while the overall flavor of coffee in green cups was highest. The CATA revealed that the coffee sample in the green cup showed the most flavor attribute. Conclusion: This study showed that cup color influenced the perceived basic taste and sensory characteristics of coffee samples.

순수 티타늄 주조체의 주형온도에 따른 용탕반응성 및 표면거칠기

차성수,송영주,박수철,Cha, Sung-Soo,Song, Young-Ju,Park, Soo-Chul 대한치과기공학회 2010 대한치과기공학회지 Vol.32 No.4

Purpose: The purpose of this study was to observe the change of metal-mold reaction and surface roughness in titanium casting specimens for phosphate-silica alumina bonded investment with mold temperatures. Methods: The metal-phosphate silica alumina bonded mold interface reaction and surface roughness of titanium casting specimens according to mold temperatures were investigated. The Specimens were analysed by scanning electron microscopy and surface roughness tester. Results: The oxidation behavior indicated by the growth of oxide thickness. The titanium-oxide layer were consisted two layer of a porous external and a dense internal one. The reaction layer and surface roughness increased with increasing investment material temperature. Conclusion: In this work, The most suitable mold temperature in casting of pure titanium was $200^{\circ}C$.

어트리션 밀링법으로 제조된 티타늄합금의 상변화 및 미세조직특성

차성수,Cha, Sung-Soo 대한치과기공학회 2001 대한치과기공학회지 Vol.23 No.1

Microstructure and phase transformation of Ti-Ni-Cu alloy powders produced by using attrition milling method were studied. Mixed powders of Ti-(50-X)Ni-XCu ($X=0{\sim}20$ at%) in composition range were mechanically alloyed for maximum 20 hours by using SUS 1/4" ball in argon atmosphere. Ball to powder ratio was 50: 1 and impeller speed was 350rpm. Mechanically alloyed with attrition millimg method. powder was heat treated at the temperature up to $850^{\circ}C$ for 1 hour in the $10^{-6}$ torr vacuum. Ti-Ni-Cu alloy powders have been fabricated by attrition milling method. and then phase transformation behaviours and microstructual properties of the alloy powders were investigated to assist in improving the the high damping capacity of Ti-Ni-Cu shape memory alloy powders. The results obtained are as follows: 1. After heat treating of fully mechanically alloyed powder at $850^{\circ}C$ for 1hour. most of the B2 and B 19' phases was formed and $TiNi_3$ were coexisted. 2. The B 19' martensite were formed in Ti-Ni-Cu alloy powders whose Cu-content is less than 5a/o. where as the B19 martensite in those whose Cu-content is more than 10at%. 3. The powders of as-milled Ti-Ni-Cu alloys whose Cu-contents is less than 5at% are amorphous. whereas those of as-milled Ti-Ni-Cu alloys whose Cu-content is more than 10at% are crystalline. This means that Cu addition tends to suppress amorphization of Ti-Ni alloy powders.

치과기공실 공기중 및 치과기공사의 혈액, 요중 중금속 함량에 관한 연구

차성수,Cha, Sung-Soo 대한치과기공학회 1988 대한치과기공학회지 Vol.10 No.1

The purpose of this study was to determine the concentration of cadmium, nickel and chromium in the air of the work-place, blood of and urine of workers and compare the level of those heavy metals by the duration of work, work-place, process of work, smoking and other factors. In this study, 48 male dental laboratory technicans and 72 office workers as the control group were subjected. The concentration of cadmium, nickel and chromium in their blood sand urine, and that of heavy metals in the air of their work-rooms were examined and analyzed from June I 1987 to September 30, 1987. The results were as follows : 1. The concentration of cadmium in the air was the highest in the porcelain part, $0.0087{\pm}0.0016mg/m^3$, that of nickel was the highest in the crown bridge part, $0.4253{\pm}0.0052mg/m^3$, and that of chrnmium was highest in the partial denture part, $0.1063{\pm}0.0024mg/m^3$. 2. cadmium, nickel and chromium concentrations in the blood and urine of dental laboratory techincians were higher that in the office workers'. Especially the concentration of cadmium in the blood($1.92{\pm}1.23{\mu}g$/100ml) of th dental laboratory techician was about two times as high as that in the office workers'($0.90{\pm}0.73{\mu}g$/100ml), and the concentration of nickel in the urine($48.53{\pm}38.83{\mu}g$/e) of the dental laboratory thchnician was about two times as high as that in the office worker's($20.24{\pm}15.35{\mu}g$/e). 3. there was no difference in the concentration of cadmium, nickel and chromium in the blood and urine with a longer duration of work. 4. The concentration of cadmium and chromium in the blood and urine differed significantly depending upon the place of work. The concentration of cadmium was the highest in the blood of dental laboratory technicians working kin the poreclain part marking at $2.53{\pm}1.08{\mu}g$/100ml. The chromium level was the heighest in the blood of partial denture park workers with a concentration of $3.60{\pm}1.02{\mu}g$/100ml. Concerning the level of cadmium in urine, it was the highest in the porcelain part workers with a concentration of $3.41{\pm}3.15{\mu}g$/e. 5. The concentration of cadmium in the urine of metal trimming and polishing group($2.64{\pm}2.41{\mu}g$/e) was higher than that of non-metal trimming and polishing group($1.39{\pm}1.18{\mu}g$/e). 6. The concentration of chromium in the blood of smoking group($2.46{\pm}1.54{\mu}g$/100ml)was higher than that lf non-smoking group($1.54{\pm}1.25{\mu}g$/100ml). 7. The height positive correlation coefficient was shown between the concentration of nickel and chromium in the blood among the all correlations between 3metals(Cd, Ni, Cr) in the blood and those in urine. The correlation coefficient was relatively high(r=0.605,,p<0.01). In general, the higher the concentration of heavy metals in the air of work places the higher the concention lf them in the blood and urine of workers, mere attention should be paid to the working environment of dental laboratory workers, Furthermore, continuous biological monitoring and further research are required for an efficient health management for dental laboratory workers.

티타늄 및 티나늄-팔라듐 합금의 수소처리에 관한 연구

차성수,Cha, Sung-Soo 대한치과기공학회 1993 대한치과기공학회지 Vol.15 No.1

Effects of hydrogenation on microstructure and mechanical properties of pure Ti and Ti-0.15Pd alloy have been studied by means of optical microscopy, differential scanning calorimeter(DSC), Xray diffraction and micro vicker's hardness test. Grain size of pure Ti and Ti-0.15Pd alloy decresed largely by hydrogenation finer than that of pure Ti and the grain size refinement was evedent in Ti-0.15Pd alloy than that in pure Ti. Ti-.015Pd alloy carried out solution treatment at 950$^{\circ}C$, the transformation of $\alpha$' martensite was occured. The amount of Hydrogen absorption in Ti-.015Pd alloy was higher than that in pure Ti. Decomposition of hydride in pure titanium and Ti-0.15Pd alloy increased largely by hydrogenation, and micro vicker's hardness of Ti-.015Pd alloy was largely than that of pure Ti by 30% after hydrogenation. The micro vicker's hardness of Ti-0.15Pd alloy after solution treatment and dehydrogenation were higher at $\beta$ phase ranger(950$^{\circ}C$) than that phase range(750$^{\circ}C$).

액화석유가스(LPG) 지하저장기지에서의 TSP(Tunnel Seismic Prediction)탐사

차성수 ( Sung Soo Cha ) 대한지구물리학회 2002 지구물리 Vol.5 No.2

치과기공실 공기중 및 치과기공사의 혈액, 요중 중금속 함량에 관한 연구

차성수(Sung Soo Cha),김종열(Chong Youl Kim) 대한치과의사협회 1988 대한치과의사협회지 Vol.26 No.11

Ti-Pd합금의 열처리에 관한 연구

차성수 ( Sung-soo Cha ) 한국고등직업교육학회 2002 한국고등직업교육학회논문집 Vol.3 No.4

Effects of hydrogen treatment and heat treatment of Ti-Pd alloys have been studied by means of microstructures, differential scanning calorimeter(DSC), X-ray diffraction and micro vickers hardness test. Hydrogen treatment was conducted m tube furnace at 520°C for 1 hour with a stream of pure hydrogen. The released gas burned in a bunsen burner. The amount of hydrogen absorption in Ti-10Pd alloy was larger than that of Ti, Ti-20Pd. Decomposition of hydride in Ti-Pd alloys occurred between 250 and 400°C. Micro vickers hardness of Ti-10Pd alloy was increased by hydrogen treatment. Ti-Pd alloys carried out heat treatment at 750°C for 1 hour. The micro vickers hardness of Ti-Pd alloys were softened by heat treatment.

Ti-Pd합금의 주조성 및 기계적 성질에 관한 연구

차성수 ( Sung-soo Cha ) 한국고등직업교육학회 2003 한국고등직업교육학회논문집 Vol.4 No.2

Titanium is known to be an adequate material for biologic use. It has been widely used in dental fields. Due to casting difficulty, its clinical use had been somewhat limited for dental cast prosthesis. Development of specific casting technique for titanium was followed by clinical use of cast fixed and removable prosthesis. But useful supportive studies for its clinical use were not enough. In this study, the castability and mechanical properties of titanium were compared with Ti-Pd alloys. Cemented crown were cross-sectioned bucco-lingually and crown fitness, margin gap and casting porosity were evaluated with SEM micrographs. The results were as follows: The mean castability of Ti and Ti-Pd alloys were satisfactory. But there were significant differences between Ti and Ti-Pd alloys. The oxide layers of cast Ti-Pd alloys invested with bonded investment were more clear than that of cast pure Ti. And Microvickers hardness of Ti-Pd alloys was increased by palladium than that of cast pure Ti.

기계적합금화를 이용한 Ti-Ni(Cu)합금의 상변태거동 및 진동감쇠능에 관한 연구

차성수 ( Sung-soo Cha ) 한국고등직업교육학회 1999 한국고등직업교육학회 학술대회 논문집 Vol.1999 No.11

Phase transformation and damping properties of Al/Ti-Ni(Cu) sintered materials were studied. The mixtures of elemental powders(Ti-48.5 ~51.5 at.%Ni, Ti-45Ni-5Cu) were mechanical alloyed by high energe ball mil to control the fraction of martensite phase. After mechanical alloying for 10 hours, Ti and Ni element were alloyed completely and amorphous phase was formed, mechanically alloyed Ti-Ni powders were heat-treated at vacuum of 10-6 torr for crystallization. Amorphous phase were crstallized to martensite(B19’ )and austenite( B2)after heat treating for 1 hour at the temperature of 850 °C, and TiNi3 intermellic compound was particlly formed. Ball milled Al/Ti-Ni composite powders were swaged at room temperature and rolled at 450°C. Considerable amount of martensite phase was remained after swaging and rolling. Damping properties of Al/Ti-Ni sintered materials measured with cantilever beam method. The damping capacity of Al/Ti-Ni was increased with Ti amount of Ti-Ni intermetallic compounds and the damping capacity was related with amount of martensite phase. The best result of damping capacity was Ti-45Ni~5Cu casting material.