• 경영과학
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• 제34권2호
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• pp.15-33
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• 2017

This paper considers a Bayesian Network analysis for understanding the heterogeneous cross-category effects of different promotion activities and developing an efficient overall promotion strategy for a large retail store. More specifically we differentiate price reduction promotion and floor promotion and study their heterogeneous effect on consumer purchase behavior under a market basket setting. We then utilize Bayesian networks in identifying complex association structure in market basket dataset by analyzing the effects of different promotional activities and also include the effects of time, family income and size. We find from our Bayesian network analysis that the dominant cross-category promotion effect of price promotion is the indirect effect whereas the dominant cross-category promotion effect of floor promotion is the direct effect. Also, among the demographic variables we find that family size of the household is linked with more product categories compared to income and see that there are differences in the extent of the effects by product category. Finally, we also show the existence of products acting as a network hub and how they can be utilized by retailers faced with a limited marketing budget and suggest a more efficient promotion strategy.

• Archives of Pharmacal Research
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• 제24권5호
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• pp.455-465
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• 2001

The highly potent cytotoxic DNA-DNA cross-linker consists of two cyclopropa[c]pyrrolo[3,4-3]indol-4(5H)-ones insoles [(+)-CPI-I] joined by a bisamido pyrrole (abbreviated to "Pyrrole"). The Pyrrole is a synthetic analog of Bizelesin, which is currently in phase II clinical trials due to its excellent in vivo antitumor activity. The Pyrrole has 10 times more potent cytotoxicity than Bizelesin and mostly form DNA-DNA interstrand cross-links through the N3 of adenines spaced 7 bp apart. The Pyrrole requires a centrally positioned GC base pair for high cross-linking reactivity (i.e., $5^1$-T$AT_2$A*-$3^1$), while Bizelesin prefers purely AT-rich sequences (i.e., $5^1$-T$AT_4$A*-$3^1$, where /(equation omitted) represents the cross-strand adenine alkylation and A* represents an adenine alkylation) (Park et al., 1996). In this study, the high-field $^1$H-NMR and rMD studies are conducted on the 1 1-mer DNA duplex adduct of the Pyrrole where the 5′(equation omitted)TAGTTA*-3′sequence is cross-linked by the drug. A severe structural perturbation is observed in the intervening sequences of cross-linking site, while a normal B-DNA structure is maintained in the region next to the drug-modified adenines. Based upon these observations, we propose that the interplay between the bisamido pyrrole unit of the drug and central C/C base pair (hydrogen-bonding interactions) is involved in the process of cross-linking reaction, and sequence specificity is the outcome of those interactions. This study suggests a mechanism for the sequence specific cross-linking reaction of the Pyrrole, and provides a further insight to develop new DNA sequence selective and distortive cross-linking agents.

• Korea-Australia Rheology Journal
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• 제21권2호
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• pp.91-102
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• 2009

This paper describes an extension of viscoelastic Group Interaction Modelling (GIM) to predict the relaxation response of linear, branched and cross-linked structures. This model is incorporated into a Monte Carlo percolation grid simulation used to generate the topological structure during the isothermal cure of a gel, so enabling the chemorheological response to be predicted at any point during the cure. The model results are compared to experimental data for an epoxy-amine systems and good agreement is observed. The viscoelastic model predicts the same exponent power-law behaviour of the loss and storage moduli as a function of frequency and predicts the cross-over in the loss tangent at the percolation condition for gelation. The model also predicts the peak in the loss tangent which occurs when the glass transition temperature surpasses the isothermal cure temperature and the system vitrifies.

• Fibers and Polymers
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• 제5권3호
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• pp.225-229
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• 2004

The effect of UV and $^60{Co}$ gamma radiations on the physical and mechanical properties of nylon 6 mono-filaments with different draw ratios has been studied. Specimens were exposed to either up to 25 Mrad of gamma or up to 168 hrs of intense UV irradiation. The results show that nylon mono-filaments exposed to gamma rays, with much higher quantum energy than UV, undergo a larger extent of molecular chain scission. Higher irradiation dose also results in the production of insoluble, macroscopic three-dimensional cross-linked network structure. The amorphous regions with a lower density of cohesive energy (lower molecular orientation) show a higher extent of cross linking reaction whereas amorphous regions with a higher density of cohesive energy (higher orientation) show higher extent of chain scission reaction, irrespective of UV ray or gamma ray irradiation.

• 한국세라믹학회지
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• 제38권6호
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• pp.593-595
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• 2001

Zinc-phosphate glasses에 B$_2$O$_3$를 도입하여 borate, phosphate, boro-phosphate networks가 혼재되어 있는 highly cross-linked structures를 형성시켜 Phosphate glasses의 화학적 안정화를 검토하였다. Raman 측정 결과 B$_2$O$_3$와 P$_2$O$_{5}$는 잘 혼화된 polynary networks를 이루고 있으며, 이렇게 하여 증진된 구조적 cross-linking에 의하여 xB$_2$O$_3$.(1-x)Zn$_2$P$_2$O$_{7}$ glasses의 T$_{g}$, T$_{d}$는 증가하였고 동시에 CTE는 감소하는 결과를 가져왔다.

• 전기학회논문지
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• 제61권6호
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• pp.916-921
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• 2012

Sealant paste with silica immersed in cross-linked epoxy-acrylate polymer resin was prepared by thermal and UV curing process. The curing mechanism of polymer resin resulted from 2 functional groups of epoxy and acrylic structure. The properties of microstructure, thermal conductivity and mechanical strength were investigated for its various applications. The adhesion strength is increased by increasing the thermal curing time until 15 minutes, and curing efficiency is saturated over 20 minutes. The increase rate per day of pot life and viscosity is 4.8%, indicating it has excellent storage stability. It is found that the formulation of silica pastes can be applied to heavy industries, building materials, display and various industries.

• Archives of Pharmacal Research
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• 제20권1호
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• pp.46-52
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• 1997

To obtain more sensitive immunoassay for methamphetamine (MA) determination, the optimum condition of enzyme-linked immunosorbent assay (ELISA) was investigated in regard to immunogens, antibody purification methods and coating tracers. Activated MA, N-(4-aminobutyl)methamphetamine (4-ABMA), was conjugated with bovine serum albumin (BSA) or keyhole limpet hemocyanin (KLH) and used as immunogen. The antibodies were purified by protein G chromatography or various immunoaffinity chromatography-linked MA-protein ligands, such as MA-BSA, MA-KLH or MA-ovalbumin (OVA). Each purified antibody was characterized by means of sensitivity and cross-reactivity using the three MA-protein coating tracers, MA-BSA, MA-KLH and MA-OVA. The best sensitivity of each antibody was acquired with the MA-OVA tracer although the tracer concentration and the antibody titer level at optimum condition were varied. The antibody with high titer level did not always yield good sensitivity. At optimum condition, immunoaffinity chromatography-purified antibodies were better for sensitivity and for specificity than protein G-purified antibodies. The cross-reactivity of the purified antibodies seemed to be affected by immunogen structure and showed somewhat different patterns according to the immunoaffinity ligand utilized. These data show that the antibody purification method as well as choice of coating tracer and immunogen is essential for the sensitivity and specificity of EIA; the optimum condition for assay should be discovered using various methods and combinations.

• International journal of advanced smart convergence
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• 제11권3호
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• pp.187-196
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• 2022

In this paper, we propose an example of designing and constructing a roof-type solar power plant structure equipped with a Pseudo-BIPV (Building-Integrated Photovoltaic) shape suitable for use as a roof of a small warehouse with a sandwich-type panel structure. As the characteristics of the roof-type solar power generation facility to be installed in the small warehouse proposed in this study, the shape of the roof is not a general A type, but a right-angled triangle shape with the slope is designed to face south. We chose a structure in which an inverter for one power plant and a control facility are linked by grouping several roofs of buildings. In addition, the height of the roof structure is less than 20 cm from the floor, and it has a shape similar to that of the BIPV, so it is building-friendly because it is almost in close contact with the roof. At the same time, the roof creates a reflective light source due to the white color. By linking this roof with a double-sided solar panel, we designed it to obtain both the advantage of the roof-friendliness and the advantage of efficiency improvement for the electric power generation based on the double-sided panel. Compared to the existing solar power generation facilities using A-shaped cross-sectional modules, the power generation efficiency of roofs in this case is increased by more than 11%, which we can confirm, through the comparison analysis of monitoring data between power plants in the same area. Therefore, if the roof-type solar structure suitable for the small warehouse we have presented in this paper is used, the facilities of electric power generation is eco-friendly. Further it is easier to obtain facility certification compared to the BIPV, and improved capacity of the power generation can be secured at low material cost. It is believed that the roof-type solar power generation facility we proposed can be usefully used for warehouse or factory-based smart housing. Sensor devices for monitoring, CCTV monitoring, or safety and environment management, operating in connection with the solar power generation facilities, are linked with the Internet of Things (IoT) solution, so they can be monitored and controlled remotely.

• 공업화학
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• 제19권3호
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• pp.299-303
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• 2008

열경화가 가능한 PPV유도체인 poly[(2,5-dimethoxy-1,4-phenylenevinylene)-alt-(1,4-phenylenevinylene)] (Cross-PPV)를 Heck coupling 반응을 이용하여 합성하였다. Cross-PPV 박막은 $200^{\circ}C$에서 경화 시키면 일반적인 유기용매에 용해되지 않는 불용성의 고분자 박막이 된다. 열경화 전 후의 Cross-PPV의 구조는 FT-IR로 확인하였으며 구조의 차이는 크지 않았다. 경화된 Cross-PPV는 일반적인 유기용매에 대하여 내용매성이 강하다. 순환전압전류법과 흡수분광법으로 측정한 경화된 Cross-PPV의 호모 및 루모 에너지 준위는 각각 -5.11 eV와 -2.56 eV으로 ITO로 부터의 정공주입장벽(hole injection barrier)이 작아(약 0.1 eV) 정공주입층으로 효과적으로 사용 할 수 있다. 호모 및 루모 에너지 준위가 각각 -5.44 eV, -3.48 eV인 poly(1,4-phenylenevinylene-(4-dicyanomethylene-4H-pyran)-2,6-vinylene-1,4-phenylene-vinylene-2,5-bis(dodecyloxy)-1,4-phenylenevinylene) (PM-PPV)을 발광층으로 사용하여 두층의 구조(bilayer structure)를 갖는 소자(ITO/crosslinked Cross-PPV/PM-PPV/Al)를 제작, 특성을 평가한 결과 최대 효율은 0.024 cd/A, 최대 발광세기는 $45cd/m^2$으로 단층형 소자(ITO/PM-PPV/Al)(최대 효율 = 0.003 cd/A, 최대 발광세기 = $3cd/m^2$)에 비하여 매우 월등한 성능을 나타냄을 확인하였다. 또한 두층의 구조를 가지는 다층형 소자의 발광스펙트럼은 단층형 소자의 발광 스펙트럼과 동일하다. 이러한 사실들로 보아 ITO 및 Al에서 주입된 전자는 모두 발광층인 PM-PPV층에서 재결합(recombination)되어 여기자(exciton)가 형성되는 것으로 사료된다.

• 임산에너지
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• 제23권1호
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• pp.45-68
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• 2004

The word of lignin is derived from the Latin word 'ligum' meaning wood. Lignin is complex polymer consisting of coniferyl alcohol, sinapyl alcohol and p-coumaryl alcohol unit and has an amorphous, three dimensional network structure which is hard to be hydrolyzed by acid. Lignin is found in the cell wall of plants lignified. The mode of polymerization of these alcohols in the cell wall lead to a heterogeneous branched and cross-linked polymer in which phenyl propane units are linked by carbon-carbon and carbon-oxygen bonds. This polymerization of precursors, p-coumaryl alcohol, coniferyl alcohol and sinapyl alcohol to lignin is formed by enzymic dehydrolyzation. The reaction is initiated by an electron transfer which results in the formation of resonance-stabilized phenoxy radical. The combination of these radicals produces a variety of dimers, trimers and oligomers and so on. Lignin research has been divided into basic and practical application field. The basic studies contains biosynthesis, chemical structure, distribution in the cell wall and reactivity by reductants, oxidants and organic solvents. The application research will be approached the reaction of lignin in various pulp making involving pulp bleaching and its effect on pulp qualities. Lignin also will be studied for the production of fine chemicals, polymer products and the conservation into an energy source like petroleum oil because the amount of lignin produced in pulp making process is more than 51,000,000 tons per year in the world. Both basic and application research must lay emphasis on the development for the utilization of lignin and the pulping process. But these researches can not be completed without understanding lignin structure containing functional groups. Therefore, this paper was focused on the review of lignin formulation which has been studied since 1948 in chronological order. This review was based on monomers, dimers, trimers and tetramers of phenyl propane unit structures which were isolated and identified by different methods from various wood.ious wood.