• 멤브레인
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• 제26권1호
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• pp.70-75
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• 2016

본 연구에서는 하수처리수를 원수로 사용하여 직접 접촉식 막증발법을 적용하여 원수 온도와 원수 유량 변화에 따른 하수처리수의 COD, TN, TP, TOC의 제거율 변화와 여과플럭스의 변화를 측정하였다. 또한 하수처리수에 의한 분리막의 오염 가역성을 평가하기 위해 1차 증류수만을 사용하여 물리세정을 수행한 후 플럭스의 회복률을 측정하였다. 실험결과 원수의 온도 및 유량에 관계없이 원수가 3배 농축될 때까지 여과를 진행하였음에도 불구하고 하수처리수의 주요 오염물질인 COD, TN, TP, TOC에 대한 제거율이 92% 이상으로 높게 나타났다. 또한 비교적 낮은 온도인 $50^{\circ}C$와 $60^{\circ}C$에서 원수의 유량에 따라 최소 13.8 LMH에서 20.3 LMH로 높은 여과플럭스를 나타냈다. 그리고 높은 농축계수까지 여과 실험을 진행했음에도 불구하고 낮은 여과플럭스의 감소를 나타냈으며 1차 증류수를 이용한 짧은 시간 동안의 물리세정만으로 최소 90% 이상의 높은 여과 플럭스 회복율을 나타냈다. 따라서 하수처리수 재이용을 위한 공정으로 막증발법의 적용이 충분히 가능할 것으로 판단된다.

• 한국세라믹학회지
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• 제36권2호
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• pp.145-150
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• 1999

고체산화물 연료전지의 양극재료로서 Gd1-xSrxMnO3을 구연산법으로 합성하였으며, 이의 결정구조, 전기전도도 및 열팽창률을 조사하였다. 또한 합성한 Gd1-xSrxMnO3을 8mol% yttria stabilized zirconia(8YSZ) 혹은 Ce0.8Gd0.2O1.9(CGO) 전해질과의 반응성을 조사하였다. Gd1-xSrxMnO3의 결정구조는 Sr함량이 증가함에 따라 orthorhombic (0$\leq$X$\leq$0.3)에서 cubic(0.4$\leq$X$\leq$0.5)을 거쳐 tetragonal (X=0.6)로 변하였다. Sr 함량이 증가함에 따라 Gd1-xSrxMnO3의 전기전도도는 증가하였다. 열팽창률은 Sr 함량이 30mol% 이상인 경우 함량이 증가함에 따라 증가하는 경향을 보이는 8YSZ, CGO와 비슷한 거동을 보였다. 8YSZ 및 CGO와의 반응성을 보기 위하여 Gd1-xSrxMnO3과 이들을 각각 혼합하여 130$0^{\circ}C$에서 48시간 동안 열처리했을 경우 8YSZ와는 SrZrO3의 반응물을 형성하였으나 CGO와는 반응을 하지 않았다.

• 대한임상전기생리학회지
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• 제9권1호
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• pp.41-49
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• 2011

This study purposes to conduct visual feedback and body posture control training on stroke patients with pusher syndrome in order to reduce their pusher syndrome. This study also examines changes resulting from the training and applies the guidelines necessary for documentation of patient/customer management. The participant for this study was one patient with pusher syndrome. The study progressed from a medical examination of the subject followed by evaluation, diagnosis, prognosis, intervention and treatment plan, and finally re-examination in order of precedence. Problems in the participant's functional activities, difficulties in changes from sitting postures into standing postures, and maintaining standing postures were determined as primary restrictions on activities and the improvement of these activities was set up as a goal through discussions with the patient. Interventions were mainly implemented to reduce the pusher syndrome with visual feedback provided using mirrors and exercises focusing on leaning in order to maintain posture while sitting. Changes from supine postures to sitting postures and the degree of changes in maintaining standing postures were compared between before and after the intervention by measuring times in the same environment and the degree of pusher syndrome was measured using the SCP tool. The process of this clinical practice was documented. The SCP score that indicates the degree of changes in the participant's pusher syndrome changed from 3.75 points to 0.8 point indicating a decrease in pushing. Among functional activities, posture changes from sitting postures to standing postures and maintaining standing postures were improved. In addition, since the patient could maintain standing postures, the patient could walk indoors. In this case study, mirrors and body posture control training used as interventions to relieve pusher syndromes can be easily applied in clinics to examine the form of functional recovery. The results indicated that these intervention methods were effective and thus it is thought that the results can be used as basic data to utilize these intervention methods diversely. In addition, the documentation of patient/client management was applied as actual documentation in Korean and based on the results, we could show decision making processes for patients' functional goals and objectively explain problems, prognoses and changes made through the interventions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.11-11
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• 2010

Thin-film-transistors (TFTs) that can be deposited at low temperature have recently attracted lots of applications such as sensors, solar cell and displays, because of the great flexible electronics and transparent. Transparent and flexible transistors are being required that high mobility and large-area uniformity at low temperature [1]. But, unfortunately most of TFT structures are used to be $SiO_2$ as gate dielectric layer. The $SiO_2$ has disadvantaged that it is required to high driving voltage to achieve the same operating efficiency compared with other high-k materials and its thickness is thicker than high-k materials [2]. To solve this problem, we find lots of high-k materials as $HfO_2$, $ZrO_2$, $SiN_x$, $TiO_2$, $Al_2O_3$. Among the High-k materials, $Al_2O_3$ is one of the outstanding materials due to its properties are high dielectric constant ( ~9 ), relatively low leakage current, wide bandgap ( 8.7 eV ) and good device stability. For the realization of flexible displays, all processes should be performed at very low temperatures, but low temperature $Al_2O_3$ grown by sputtering showed deteriorated electrical performance. Further decrease in growth temperature induces a high density of charge traps in the gate oxide/channel. This study investigated the effect of growth temperatures of ALD grown $Al_2O_3$ layers on the TFT device performance. The ALD deposition showed high conformal and defect-free dielectric layers at low temperature compared with other deposition equipments [2]. After ITO was wet-chemically etched with HCl : $HNO_3$ = 3:1, $Al_2O_3$ layer was deposited by ALD at various growth temperatures or lift-off process. Amorphous InGaZnO channel layers were deposited by rf magnetron sputtering at a working pressure of 3 mTorr and $O_2$/Ar (1/29 sccm). The electrodes were formed with electron-beam evaporated Ti (30 nm) and Au (70 nm) bilayer. The TFT devices were heat-treated in a furnace at $300^{\circ}C$ and nitrogen atmosphere for 1 hour by rapid thermal treatment. The electrical properties of the oxide TFTs were measured using semiconductor parameter analyzer (4145B), and LCR meter.

• Journal of Periodontal and Implant Science
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• 제26권4호
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• pp.873-887
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• 1996

Platelet-derived growth factor(PDGF) is one of the polypeptide growth fators. PDGF has been reported as a biological mediator which regulates activities of wound healing process including the cell proliferation, migration and metabolism. Recent studies indicated that demineralized root surface as the primary site for growth factor application has advantages over other application method, especially due to binding capacity of growth factor for exposed matrix component of deminera1ized dentin surface. The purpose of this study is to evaluate optimal application time of PDGF-BB on proliferation of human gingival fibroblasts using deminera1ized dentin surface as primary application site. Human gingival fibroblasts and dentin slabs were prepared from the first premolar tooth extracted for the orthodontic treatment, cells were cultured in DMEM/I0% FBS at the $37^{\circ}C$, 5% CO2 incubator. All of the dentin slabs were preconditioned with Tetracycline HCI(100mg/ml) solution and rinsed in PBS. In the cell proliferation experiment, experimental group was immersed in DMEM containing 10% FBS, 50ng/rnl PDGF-BB during different time(30sec, 1, 2, 4, 8 minutes) and dried. Cells at concentration of $1{\times}10^5$cells/ml were seeded in each culture well which contained dentin slabs and incubated for 6 hours. Then, all of the dentin slabs were moved into new 24 well culture dish and incubated for 24, 48, 72 hours. The cell counting was done by hemocytometer with inverted phase contrast microscope after trypsinization. The results were as follows : The application of PDGF-BB for 1, 2 min slightly increased the number of gingival fibroblasts, and the application of PDGF-BB for 4, 8 min prominently increased the number of gingival fibroblasts. The application of PDGF-BB for 4 min showed maximum proliferation rate of gingival fibroblasts at 24, 48, 72 hours, and the application of PDGF-BB for 8 min showed less proliferation rate of gingival fibroblasts compared to the application of PDGF-BB for 4 min at 24, 48, 72 hours. In conclusion, the application of PDGF-BB for 4 min appeared to be optimal to obtain maximum proliferation of gingival fibroblasts using demineralized dentin surface as primary applicaton site of PDGF-BB.

• 복식
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• 제44권
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• pp.181-199
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• 1999

The industry of modern clothing has deviated from the overflow of commercialism and the standardization and nowadays is going toward pursuing art, creativity, and high added value. This trend brings the return of the natural materials from the synthetic textiles and increases the value of old and handmade fabrics. Finally, the handmade-paper, which is a natural material, comes to be reconsidered as a new material for the clothing. Therefore, as the natural materials and the manufacture of handmade clothing are rising again, the qualitative improvement and globalization of clothing industry should be first realized through the developments of creative and various clothing materials and new expressing techniques. The above investigation and study have been synthesized and analyzed as follows: First, through the study on the origin of the paper clothing, its historical background and the process of its development, we've learned these two facts following : the paper clothing of the East in the past mostly had practiced meanings. On the other hand, in the West it had meanings which were raised the artist's emotions and beauty-consciousness to the artistic level by the various kinds of expressing methods. Second, handmade-paper was manufactured by the embedding method, which mixed mulberry pulp, gauze, corn, hair, sisal, silk and so on. It was found that handmade-paper had the affluent and proper texture as the clothing material and was be able to control the clarity through the variation of thickness. It was also confirmed that the creative and original texture with hand-worked molding beauty was obtained by the use of handmade-paper. Third, when the handmade-paper is used, the molding beauty of plane, relievo, and solid can be freely pursued, and various and effective molding conformation can be constructed by the effect of superposition and repetition. Also, because the maximum discretion from the various optional manufacturing methods is allowed, the molding beauty can be maximized when the clothes are manufactured with handmade-paper. Fourth, the gauze with strong drape was combined to overcome the stiffness and the tearing of the paper. As a result, the durability and the wearability of the paper were strengthened and thus the thus the applications as the clothing material were enlarged. In conclusion, in order to enhance the value, creativity, practicality, and artistic sense of the design for modern clothing, the clothes made of handmade-paper should be more studied. Moreover, for the generalization of paper clothes, the studies on the development of practical paper with paper with water resistance, post-treatment after dyeing, flexibility, and durability should be done. I really hope that this study will be the motive to provoke the possibility of handmade-paper as new clothing material in not only practical sense but also artistic sense.

• 한국식품영양학회지
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• 제17권3호
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• pp.246-253
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• 2004

본 연구에서는 초산과 가열로 연화된 다시마의 유연조직을 유지하기 위하여 친수성이 강한hydrocolloid를 사용, 저장 중 연화 안정성, 열 용융 특성 및 점성, 관능성 등의 변화를 검토하였다. 그 결과 Avrami equation에서 고화속도상수는 carrageenan이 0.05로 가장 작게 나타났으며 저장기간 동안 연화 다시마 paste의 경도는 carrageenan의 경우는 저장 2일후에 거의 변화를 보이지 않았다. 또 경도속도는 carrageenan이 0.28 kg/mm/day로 가장 작게 나타났다. 연화 다시마 paste의 열용융 신전성(伸剪性)은 carrageenan이 가장 좋은 것으로 나타났으며 유동특성은 rheopectic을 나타내었다. 특히 carrageenan은 경시적인 점성 변화가 가장 적게 일어났으며 유의차(p<0.05)를 나타내었다. 연화 다시마의 L, a, b값의 변화는carrageenan의 경우 다른 것과 유의차를 보였으며(p<0.05) 색깔 선호도, 냄새, 응집성, 연화 정도, 가공 접합성, 그리고 전반적인 기호성 등은 carrageenan이 가장 좋은 것으로 나타났다. 결론적으로 친수성 hydrocolloid의 사용은 연화 다시마 Paste의 품질과 저장 안정성에 좋은 영향을 미치고 그 중 carrageenen이 연화 안정성에 가장 좋은 것으로 나타났다.

• 동아시아식생활학회지
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• 제25권1호
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• pp.139-145
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• 2015

본 연구에는 메밀을 ${\alpha}$-amylase, ${\beta}$-amylase, glucoamylase 세 종류의 효소로 당화한 결과, 당도와 rutin, quercetin, 총 폴리페놀 함량이 증가하였고, 항산화 활성이 개선됨을 확인하였다. 당화 전 약 $1^{\circ}Brix$를 나타내던 메밀은 ${\alpha}$-amylase, ${\beta}$-amylase, glucoamylase로 당화하였을 때 최고 $10.27^{\circ}Brix$, $5.13^{\circ}Brix$, $11.13^{\circ}Brix$를 각각 나타내었다. Rutin과 quercetin의 함량도 당화 전보다 당화를 거치면서 증가하는 경향을 나타내었으며, ${\alpha}$-amylase로 당화하였을 때 rutin은 1.76배, quercetin은 2.09배 증가하였으며, ${\beta}$-amylase로 당화하였을 때 rutin은 1.58배 증가하였으며, glucoamylase로 당화하였을 때 rutin은 3.36배, quercetin은 6.58배 증가하였다. 총 폴리페놀과 DPPH radical 소거능을 측정한 결과, 당화를 하기 전과 비교하여 당화 후 총 폴리페놀 함량과 DPPH radical 소거능이 유의하게 증가하였다. 이러한 결과를 바탕으로 메밀의 당화는 메밀에 함유되어 있는 기능성 성분을 증가시켜 기능성 식품으로의 개발가능성을 높이는 것으로 판단된다.

• Physical Therapy Rehabilitation Science
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• 제5권3호
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• pp.138-142
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• 2016

Objective: The purpose of this study was to investigate how light touch with a finger affects balance ability when a posture is maintained in the condition of visual information blockage and to provide a fundamental material for developing balance ability in the process of rehabilitation treatment. Design: Cross-sectional study. Methods: The study subjects were 17 healthy men and women in their twenties and thirties who were studying at S University in Seoul. The system was comprised of an equilateral triangular force platform. Subjects were asked to step on the foot position of the force platform (Good Balance, Finland) barefooted for 30 seconds, with eyes closed, hands hanging down loosely, and feet comfortably apart. It was connected to a laptop by using Bluetooth technology. An experiment was conducted in the following three circumstances: 1) no-touch trial, 2) light touch to the back (T7 area), and 3) light touch to the middle finger of the left hand. Each subject was given a 10-minute break between consecutive measurements. The experimental circumstances were performed randomly. Anteroposterior sway (APSV), mediolateral sway velocity (MLSV), and velocity moment (VM) were measured. Results: The APSVs (mm/s) were $9.32{\pm}3.37$ and $5.45{\pm}2.98$; the MLSVs (mm/s), $6.39{\pm}3.35$ and $3.31{\pm}2.48$; and VM ($mm^2/s$), $17.13{\pm}11.75$ and $6.76{\pm}8.31$ in the first and second experimental circumstances, respectively. APSV, MLSV, and VM values were significantly improved with the 1) no-touch trial and 2) light touch to the back trail conditions compared with the 3) light touch to the middle finger of the left hand condition (p<0.05). Conclusions: This study revealed that the balance ability for maintaining a body posture was influenced more by light touch to the back (T7) than by light touch with the sensitive fingertip and body sway diminished after visual information was blocked.

• 공업화학
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• 제29권2호
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• pp.215-224
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• 2018

염산 5, 10, 15 wt% 용액(1.5, 3.0, 4.5 M; 석유정 산성화에 사용되는 범위)에 대하여 여러 가지 조건에서 자기장이 미치는 영향을 연구하였다. 자화된 염산의 pH 변화를 정상적인 염산과 비교하였다. Taguchi 실험 설계법을 사용하여 자장강도, 농도, 유속, 온도 및 시간의 영향을 모델링하였다. 실험 결과 자화에 따라 염산의 $H^+$ 농도가 42%까지 감소하였다. 자장 강도(기여도 28%), 염산의 농도(기여도 42%), 유속이 커지면 자기장 적용의 효과가 증가하였다. 염산에 대한 자기장의 영향은 용액의 유속과 가열에 의하여 영향받지 않았으며 시간에 따른 자기장 메모리가 유지되는 것으로 나타났다. 최대 $H^+$ 농도 변화에 대한 최적의 조합은 10% 염산 용액 및 4,300 Gauss일 때로 얻어졌다. 자화 과정 중 염산의 반응 속도가 감소하므로 자화된 염산은 탄화수소(원유 및 천연가스)정의 매질 산성화에 대한 대체 지연제로 비용면에서 경제적이고 신뢰성 있는 방법이 될 것으로 제안한다.