• 대한화학회지
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• 제51권1호
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• pp.14-20
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• 2007

금(Au) 전극 위에 전해 석출한 철족 원소(Fe, Co, Ni)를 전극으로 phthalate 완충 용액에서 철족 원소의 부식과정을 조사하였다. Phthalate 완충용액의 pH의 변화에 대한 부식전위와 부식전류를 측정하여 각 원소(Fe, Co, Ni)전극의 산화반응과 환원반응에 대한 Tafel 기울기를 구하였으며 Tafel 기울기를 포함한 정량적인 전기화학 인자를 측정하여 전극의 산화반응과 환원반응에 대한 반응 메커니즘을 제안하였다. Phthalate 완충 용액에 존재하는 화학 종의 흡착은 철족 원소 전극의 산화반응에 영향을 미치는 것으로 보인다.

• 전기화학회지
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• 제10권1호
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• pp.14-19
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• 2007

Cu-RDE를 이용하여 borate 완충용액에서 Cu의 부식과 부동화 과정의 반응구조를 연구하였다. 혼합 전위(mixed potential) 이론을 도입하여 대류확산의 조건(convective diffusion)에서 회전속도의 증가에 따라 부식전위가 양의 방향으로 증가하는 모형을 발견하였다. 산화에 의한 생성물은 중간물질 $Cu(OH)_{ads}$를 거쳐, 부식, 부동화의 시작, 중간, 마지막 등의 영역에서 각각 ${Cu(OH)_2}^-,\;Cu_2O,\;Cu(OH)_2,\;CuO$인 것으로 제안하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.1041-1044
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• 1999

This paper propose a solution to resolve data overflow or leakage when a subscriber receive data to service provider. The set-top box can communicate with a service provider and can inform the service provider its data overflow or leakage. When service provider received this control signal, it changes data transmit rate and transmits data with changed rate. The buffer of set-top box is important because incoming data from a service provider are stored by it.

• 산업융합연구
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• 제5권2호
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• pp.21-32
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• 2007

This paper deals with the sequencing problem in the operation of the manufacturing systems with the constraint of buffer capacity. Some of studies for this theme have been progressed for several years. And then most of them considered only one objective, such as maximum lateness, machine utilization, makespan, mean flowtime and so on. This study deal with two objectives of the delivery for customers and the idle time of machines for producers. For the decision of sequence, the utility function is used. The developed heuristic algorithm presents a good solution. Through a numerical example, the procedures of the job sequencing is explained.

• Restorative Dentistry and Endodontics
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• 제26권4호
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• pp.341-349
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• 2001

Dental caries is the most common oral disease. There are many factors contributing to its development, but complete understanding and prevention are not fully known. However, it is possible to remineralize the early enamel curious lesion by fluoride containing remineralization solution. Recently the pH-cycling model has been used to examine the effect of fluoride solution on remineralization of artificial caries in vitro as it can closely simulate the conditions encountered in vivo within a carefully controlled environment. The aim of this study was to evaluate the remineralizing effects of supersaturated buffer solutions under pH-cycling model. The specimen with 3mm-diameter was made using mature bovine incisors which has no caries and has sound enamel surface. Early curious lesions were produced by suspending each specimens into demineralization solution at pH 5.0 for 33 hours and the specimen whose surface hardness value ranged from 25 to 45 VHN were used. The pH cycling treatment regimen consisted of 5 min soaks of three treatment solutions four times per days for 15 days and the continuous cycling of demineralization and remineralization were carried out for 15 days. Following the pH-cycling treatment regimen, the specimens' surface microhardness were measured by the Vickers hardness test (VHN) and analyzed by ANOVA and Duncan's multiple-range test. 1. The surface microhardness value of supersaturated solution, Senstime, and Gagline groups were increased after pH cycling, and that of supersaturated solution was significantly Increased compared to saline group(P<0.05). 2. The surface remineralization effect of fluoride containing solutions was accelerated by saliva under pH-cycling mode 3. The pH cycling model was considered appropriate to mimic the intra-oral pH changes when evaluating demineralization and remineralization in vitro. Under the results of above study, salivary remineralization effect can be improved by fluoride containing remineralization solution. The pH-cycling model was considered appropriate to mimic the intra-oral pH changes when evaluating demineralization and remineralization in vitro.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.263-268
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• 2001

In this paper, we present a new heuristic algorithm fur buffer allocation in FMS (Flexible Manufacturing System). It is conducted by using a genetic algorithm and simulation. First, we model the system by using a simulation software, \"Arena\". Then, we apply a genetic algorithm to achieve an optimal solution. VBA blocks, which are kinds of add-in functions in Arena, are used to connect Arena with the genetic algorithm. The system being modeled has seven workstations, one loading/unloading station, and three AGVs (Automated Guided Vehicle). Also it contains three products, which each have their own machining order and processing times. We experimented with two kinds of buffer allocation problems with a proposed heuristic algorithm, and we will suggest a simple heuristic approach based on processing times and workloads to validate our proposed algorithm. The first experiment is to find a buffer profile to achieve the maximum throughput using a finite number of buffers. The second experiment is to find the minimum number of buffers to achieve the desired throughput. End of this paper, we compare the result of a proposed algorithm with the result of a simple buffer allocation heuristic based on processing times and workloads. We show that the proposed algorithm increase the throughput by 7.2%.t by 7.2%.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.146-148
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• 2012

In our study, we have focused on optimizing good quality of ZnS buffer layer by chemical bath deposition (CBD) from a bath containing $ZnSO_4$, Thiourea and Ammonia in aqueous solution onto CIGS solar cells. The influence of deposition parameter such as pH, deposition temperature, stirring speed played a very important role on transmission, homogeneity, crystalline of ZnS buffer layer. The transmission spectrum showed a good transmission characteristic above 80% invisible spectral region. CIGS thin flim solar cell with ZnS buffer layer has been realized with the efficiency of 14.2%.

• 한국식품과학회지
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• 제32권5호
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• pp.1122-1127
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• 2000

자몽씨 추출물, 키토산, 인산용액을 콩나물 재배용수로 사용하여 콩나물 부패를 억제할 수 있는 재배방법을 검토하였다. 키토산과 인산용액은 콩나물의 생장에 특별한 저해를 일으키지 않으면서 재배수율을 증가시켰으며 특히 인산용액의 수율 증가와 부패억제 효과가 우수하였다. 인산용액의 관수회수가 증가함에 따라 대조구에 비해 12.3% 까지 수율이 증가하였으며 $4{\sim}8$회의 적은 관수회수에서도 높은 수율 증가와 뚜렷한 부패억제 효과를 확인하였다.

• 대한화학회지
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• 제19권5호
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• pp.381-385
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• 1975

Alunite 鑛으로 부터 칼륨과 알루미늄 成分을 完全히 分離하여 내는 方法으로 pH8.0인 緩衝溶液과의 反應에서 反應速度와 反應機構를 究明했다.

• 대한화학회지
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• 제56권1호
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• pp.47-53
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• 2012

Borate 완충용액에서 Zn의 부동화 피막이 생성되는 과정과 부동화 피막의 전기적 특성을 조사하였다. 이 때 생성되는 산화피막은 Mott-Schottky 식이 적용되는 n-형 반도체 성질을 보였으며, ZnO와 $Zn(OH)_2$로 구성되어 두 종류의 주개(깊은 주개와 얕은 주개)가 존재함을 알 수 있었다.