• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.1-7
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• 2018

The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay is commonly used for analyzing the cell viability. In this study, effects of various solvents, different lights, and zinc protoporphyrin (ZnPP) on the chemical behavior of MTT formazan were investigated. The color response of MTT formazan in NaOH was highly pronounced; the absorbance of MTT formazan in 0.1 N NaOH at 550 nm was >2-fold higher than that in water, dimethyl sulfoxide (DMSO), methanol, and ethanol. MTT formazan in DMSO and NaOH (>0.1 N) was relatively stable under fluorescent and UV light at 365 nm; its rapid degradation was induced under UV light at 254 nm in all solvents. ZnPP degraded MTT formazan under light in a time- and concentration-dependent manner; MTT formazan in 0.1 N NaOH was the most sensitive to ZnPP, followed by DMSO. These results suggest that NaOH and DMSO might be suitable media for MTT formazan for monitoring photosensitizing properties.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.52-52
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• 2012

Poly(phenylene sulfide)(PPS)는 내열성 및 내화학성이 뛰어난 고분자 소재로, 대표적인 엔지니어링 플라스틱 중 하나이다. PPS는 벤젠 링에 황원자가 파라 치환 형태로 교대로 존재하는 결정성 고분자이며, 다른 대부분의 고성능 섬유고분자가 용융되지 않는 것과는 달리 용융되는 열가소성 소재이다. PPS는 높은 내약품성과 열에 대한 장기적인 안정성을 나타내고, 방염제 첨가 없이도 방염화가 가능하며, 전기 절연성이 뛰어나고, 형태안정성도 우수하다. 또한 $200^{\circ}C$ 이하에서는 어떤 용매에도 용해되지 않으며, $200^{\circ}C$ 이상에서도 몇 가지 방향족 화합물에만 제한된 범위 내에서 용해되는 우수한 내약품성을 나타낸다. PPS의 내열성을 더욱 우수하게 하기 위해 고분자 사슬을 가교할 수 있다. 가교에는 열처리 또는 감마선, 전자선, 자외선 조사를 이용할 수 있는데 열에 의한 가교는 균일한 열전달과 고온이 필요하며 감마선 및 전자선 조사는 설비의 고비용과 방사선 노출 위험으로 인해 비친환경적이다. 반면에 자외선 조사법은 다루기 쉽고 비용이 적게 들고 친환경적인 장점을 가진다. 본 연구에서는 PPS film의 열안정성을 향상시키기 위해 자외선 조사를 이용하여 PPS film의 광가교를 수행하였다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.05a
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• pp.87-91
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• 2008

The study examined fire resistance of concrete followed by change of mixed rate in PP and NY composite fiber and the results were as follows. In the event of fluidity in concrete not set, plane satisfied 600±100, its target slump flow, and fluidity was reduced as organic fiber's mixed rate was increased. Air amount satisfied 3.0±1.0, its target air amount, and didn't have distinct differences in reduction and increase according to organic fiber's kind and change of its mixed rate. However, it had a tendency that fluidity was reduced as the mixed rate was increased. In characteristics of hardening concrete, the 28th day compressive strength followed by organic fiber's kind and change of its mixed rate didn't have a lot of differences and satisfied high strength scope as about 70MPa. In spalling characteristics after fire resistance test, spalling was happened in non-mixture, plane combination, and P1N0. In other combinations, spalling resistance was happened. The relic compressive strength rate was 56%, the best condition, in P3N1(PP0.03%, NY0.01% compositeness) mixing PP fiber with NY fiber at once.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.6
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• pp.55-64
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• 2017

High-capacity, high-definition image applications need to process considerable amounts of data at high speed. Accordingly, users of these applications demand a high-speed parallel execution system. To increase the speed of a parallel execution system, Park (2004) proposed a technique, called MAMS (Multi-Access Memory System), to access data in several execution units without the conflict of parallel processing memories. Since then, many studies on MAMS have been conducted, furthering the technique to MAMS-PP16 and MAMS-PP64, among others. As a memory architecture for parallel processing, MAMS must be constructed in one chip; therefore, a method to achieve the identical functionality as the existing MAMS while minimizing the architecture needs to be studied. This study proposes a method of miniaturizing the MAMS architecture in which the architectures of the ACR (Address Calculation and Routing) circuit and MMS (Memory Module Selection) circuit, which deliver data in memories to parallel execution units (PEs), do not use the MMS circuit, but are constructed as one shift and conditional statements whose number is the same as that of memory modules inside the ACR circuit. To verify the performance of the realized architecture, the study conducted the processing time of the proposed MAMS-PP64 through an image correlation test, the results of which demonstrated that the ratio of the image correlation from the proposed architecture was improved by 1.05 on average.

• Journal of the Korean Operations Research and Management Science Society
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• v.36 no.4
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• pp.43-61
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• 2011

We first develop a value ecosystem framework to model the SDP(Service Delivery Process) of web services. Since the web service has been evolving from the basic web architecture (e.g., traditional world wide web) to a prosuming platform based on virtualization technologies, the proposed framework of the value ecosystem focuses on capturing the key characteristics of SDP in each type of web services. Even though they share the basic elements such as PP(Platform Provider), CA(Customization Agency) and user group, the SDP in the traditional web services (so-called Web1.0 in this paper) is quite different from the most recent one (so-called Web2.0). In our value ecosystem, users are uniformly distributed over (0, ${\Delta}$), where ${\Delta}$��represents the variety level of users' preference on the web service level. PP and CA provide a standard level of web service(s) and prosuming service package, respectively. CA in Web1.0 presents a standard customization package($s_a$) at flat rate c, whereas PP and CA collaborate and provide customization service with a usage-based scheme. We employ a multi-stage game model to analyze and compare the SDPs in Web1.0 and Web2.0. Our findings through analysis and numerical simulations are as follows. First, the user group is consecutively segmented, and the pattern of the segmentations varies across Web1.0 and Web2.0. The standardized service level s (from PP) is higher in Web1.0, whereas the amount of information created in the value ecosystem is bigger in Web2.0. This indicates the role of CA would be increasingly critical in Web2.0: in particular, for fulfilling the needs of prosuming and service customization.

• Journal of Photoscience
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• v.9 no.2
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• pp.102-105
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• 2002

Phoborhodopsin (pR or sensory rhodopsin II, sRII; the absorption maximum of ∼ 500 nm) is a retinoid protein and works as a photoreceptor of the negative phototaxis of Halobacterium salinarum. pharaonis phoborhodopsin (ppR or pharaonis sensory rhodopsin II, psRII) is a corresponding protein of Natronobacterium pharaonis. These sensory proteins form a complex with a cognate transducer protein in the membrane, and this complex transmits the light-signal to the cytoplasm to evoke avoidance reaction from blue-green light. Recently, the functional expression in Escherichia coli membrane of ppR was achieved, which can afford a large amount of the protein and enables mutant studies to clarify the role of various amino acid residues. A truncated transducer which can bind to ppR is also expressed in Escherichia. coli membrane. In this article, we will review properties of ppR mainly using observations of our laboratory; which contains photochemistry (photocycle), light-driven proton uptake, release and transport, F -helix titling during photocycle and association of the transducer.

• Composites Research
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• v.13 no.2
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• pp.81-90
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• 2000

For automotive applications, a sandwich sheet which was made of a 5182 aluminum alloy (AA5182) sheet and a polypropylene (PP) sheet, AA5182/PP/AA5182, has been developed. In order to evaluate its formability, the forming limit diagrams (FLD) of the 5182 aluminum alloy sheet with 0.2mm thickness and the sandwich sheet with 1.2mm thickness have been obtained based on the modified Marciniak-Kuczynski (M-K) theory. To account for the anisotropy of the sheet, Hill's 1948 yield function has been applied. The FLD of the sandwich sheet was predicted to be better than that of the AA5182 sheet, which was well confirmed by experiments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.1C
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• pp.59-64
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• 2004

We propose a new RLL(run length limited) (2,7) PP(parity preserving) code with 4 RMTR(repeated minimum transition run) for optical recording. The proposed code has better characteristics in terms of density ratio, RMTR, DC(direct current) component suppression, BER(bit error rate) and system complexity than (2,1O) code that currently applied in storage systems and (1,7) PP code that highly recommended as the next generation optical recording system. Some characteristics of the code are described with several simulations. And the proposed code's superiorites in performance is illustrated as compared with the other codes.

• Clean Technology
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• v.23 no.4
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• pp.388-392
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• 2017

In this study, a quantitative environmental impact assessment for the production process of breathable film was conducted employing Life Cycle Assessment (LCA) methodology. Among the various categories, Global Warming (GW) accounted for the highest impact (97%) followed by Human Toxicity (HT). And the key substances of various impact categories included HDPE, PP, and electricity. In the production process, the high impact resulted from mixing process (57%), lamination process (29%), and extruder process (10%). To improve environmental impact, it is necessary to design a new process system that reduces the amount of electricity used and that increases production yields, if raw materials such as HDPE and PP owe excluded.

• Journal of the Korea Institute of Building Construction
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• v.11 no.4
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• pp.353-362
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• 2011

High Strength Concrete (HSC) has weakness that in a fire, it is spalled and brittles. The phenomenon of spalling is made by water vapor's being confined in watertight concrete. This study is aimed to evaluate explosive spalling properties of high strength concrete with ${\square}100{\times}100{\times}200$ mm specimen and ${\square}400{\times}400{\times}1500$ mm column. To prevent spalling of concrete, fireproof coating and PP fiber are used. As a result, ${\square}400{\times}400{\times}1500$ mm column was prevented spalling likes ${\times}100{\times}100{\times}200$ mm specimen. When concrete protected failure to explosive spalling, quantity heat ratio (which fireproof coating specimen to pp fiber mixed specimen) between ${\square}100{\times}100{\times}200$ mm and ${\square}400{\times}400{\times}1500$ mm was maximum value at 20 minute, but difference of quantity heat ratio decreased and quantity heat ratio of each specimen is almost same at 30 minute.