• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.244-244
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• 2012

Polymer memory devices have attracted considerable attention because of their advantages such as low cost potential, good scalability, flexibility, simplicity in structure, and large capacity for data storage. Metal/poly (4,4'-aminotriphenylene hexafluoroisopropylidenediphthalimide) (6F-TPA PI)/metal system has been found to show an electrical bi-stable behavior. Here, we show a novel set-up of 6F-TPA PI/Al sample in which holes are injected by photoelectron emission process instead of direct charge carrier injection via metal electrode. In this process, an irreversible electrical phase transition of 6F-TPA PI is found, leading to a write-once-read-many (WORM) behavior. The photoelectron spectroscopy results measured before and after the switching process revealed that the irreversible electrical phase transition of 6F-TPA PI is attributed to the chemical modification of the carbonyl group in phthalimide moiety.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.359-360
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• 2002

A bacterial strain able to degrade terephthalic acid (TPA) was isolated and identified to belong to the Corynebacterium sp. It was named Corynebacterium sp. YT-14. When stirred loop bioreactor was used in a batch type system for removing terephthalic acid from weight loss treatment wastewater and complex dyeing process wastwater, the removal efficiency of terephthalic acid was 85.4% after 7 days of treatment of the weight loss treatment wastewater, while no residual terephthalic acid was detected after 3 days of treatment of the complex dyeing process wastewater

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.266-266
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• 2013

We show a set-up of poly (4,4'-aminotriphenylene hexafluoroisopropylidenediphthalimide) (6F-TPA PI)/Al sample in which holes are injected by photoelectron emission process instead of direct charge carrier injection via metal electrode. In this process, an irreversible electrical phase transition of 6F-TPA PI is found in contrast to the Al/6F-TPA PI/Al structure, leading to a write-once-readmany behavior. The photoelectron spectroscopy results measured before and after the switching process revealed that the irreversible electrical phase transition of 6F-TPA PI is attributed to the chemical modification of the carbonyl group in phthalimide moiety.

• Journal of Environmental Health Sciences
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• v.23 no.3
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• pp.85-90
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• 1997

The objective of this study was to investigate biodegradation of TPA(terephthalic acid) and EG (ethylene glycol), treatment efficiency of polyester weight loss wastewater and microbial characteristics by aerated submerged biolfilm(ASB) p.rocess. In a batch reactor, pH increased from 7.0 to 8. 5 in the biodegradation of TPA. Whereas, in case of EG, decreased from 7.0 to 5.2. COD concentration rapidly decreased within 24hr in the biodegradation of TPA and EG. COD removal velocity constant(k) were 0.065-0.088 hr$^{-1}$. The biodegradation velocity of TPA was 1.4 times faster than that of EG. The ratio of suspended biomass to the total biomass in the reactor was 18.3-33.3%, increased as a high ratio of EG content. Biofilm thickness, biofilm dry density and attached biomass were 346-432 $\mu$m, 41.8-61.9 mg/cm$^3$, 1.45-2.67 mg/cm$^2$, respectively. There values increased as a high ratio of TPA content. In the hydraulic retention time of 36 hr, organic loading rate of 4 kgCOD/m$^3\cdot$ day and packing ratio of 70%, the effluent concentrations of TCOD, SCOD in a continuous flow reator were 1,388 mg/l, 147 mg/l and removal efficiencies were 77%, 97.6%, respectively.

• The Korean Journal of Zoology
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• v.39 no.3
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• pp.266-272
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• 1996

Experiments were carried out to ascertain whether gonadotropin or a phorbol ester (12-O-tetradecanoyl phorbol-13-acetate, TPA) induces oocyte ovulation and stimulates prostaglandin synthesis by Rana ovarian follicles in vitro. Rana nigromaculata collected from underground in spring were utilized for the present experiment. Treatment of frog pituitary homogenate (FPH) or TPA to ovarian fragments in culture induced oocyte ovulation in a dose dependent manner and stimulated prostaglandin F2a (PGF$_2$$\alpha$ synthesis. Both treatruents were more effective in inducing the ovulation and PGF$_2$$\alpha$ secretion by the follicles obtained in May than those in April. A Protein kinase C inactivator, 1-(5-isoquinolinyl-sulfonyl)-2-methyl-piperazine (H-7), or cyclooxygenase inhibitor, indomethacin (IM) suppressed the FPH- or TPA-induced PGF$_2$$\alpha$ production, but IM failed to suppress the FPH- or TPA-induced ovulation. Time course of oocyte ovulation and PGF$_2$$\alpha$ secretion by FPH and TPA treatments were very similar to each other. FPH stimulated progesterone secretion by the follicle but TPA failed to do so. Taken together, the data presented here suggest that protein kinase C (PKC) in follicle play a role in the ovulation process of Rana nigromaculata, probably via prostaglandin synthesis.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.5
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• pp.480-486
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• 2006

On account of exchanging main process from chemical precipitation for MLE(Modified Ludzark-Ettinger), an external carbon source was required for supplementation of carbon source shortage that was needed biological denitrification in the S sewage treatment plant(S-STP). In this study, NUR(nitrate uptake rate), OUR(oxygen uptake rate) test and a field application test was conducted for the applicability assessment of Terephtalic acid(TPA) by-product contained about 4.7% acetate as alternative external carbon source. As the results, TPA by-product shows more rapid acclimation than methanol, 8.24 mg ${NO_3}^--N/g$ VSS/hr specific denitrification rate, 3.70 g $COD_{Cr}/g\;NO_3$ C/N ratio and 99.4% readily biodegradable COD contents. In the results of field application, the nutrient removal efficiency was high and effluent T-N concentration is 8.2 mg/L. It is concluded that TPA by-product is the proper alternative external carbon source.

• The Mathematical Education
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• v.62 no.2
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• pp.211-236
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• 2023

The purpose of this study is to derive implications of preservice mathematics teacher education in Korea by analyzing the case of edTPA used in the preservice teacher training process in the United States. Recently, there has been a growing interest in promoting professional competencies considering not only the cognitive dimension related to knowledge development of preservice mathematics teachers but also the situational dimension considering reality in the classroom. The edTPA in the United States is a performance-based assessment based on lessons conducted by preservice teachers at school. This study analyzes the professional competencies required of preservice mathematics teachers by analyzing handbooks that described the case of edTPA in which preservice mathematics teachers in the United States participate. The edTPA includes planning, instruction, and assessment tasks, and continuous tasks are performed in connection with classes. Thus, the analysis is conducted on the points of linkage between the description of evaluation items and criteria in the planning, instruction, and assessment tasks, as well as the professional competencies required from that linkage. As a result of analyzing the edTPA handbooks, the professional competencies required of preservice mathematics teachers in the edTPA assessment were the competency to focus on and implement specific mathematics lessons, the competency to reflectively understand the implementation and assessment of specific mathematics lessons, and the competency to make a progressive determination of students' achievement related to their learning and their uses of language and representations. The results of this analysis can be used as constructs for competencies that can be assessed in the preservice in the organization of the preservice mathematics teacher curriculum and practice training semester system in Korea.

• ETRI Journal
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• v.24 no.3
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• pp.221-225
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• 2002

We performed nonlinear transmission measurements and quantum-chemical calculations on dithienothiophene(DTT)-based molecules to gain insight into the effect of acceptor and donor groups on two-photon absorption(TPA) properties. The TPA intensity showed dispersion characteristics of the single-photon absorption spectrum. When the molecules included an asymmetric donor-acceptor pair, the single- and two-photon absorption maximum wavelengths were red-shifted more than when the molecules had a symmetric donor-donor structure. We interpreted this result as indicating that the $S_2$ state plays the dominating role in the absorption process of molecules with a symmetric structure. The experimental TPA ${\delta}$ values at the absorption peak wavelength showed a dependence on the structural variations. We found the self-consistent force-field theory and Hartree-Fock Hamiltonian with single configuration interaction formalism to be valid for evaluating TPA ${\delta}$. Although the quantum-chemical calculations slightly underestimated the experimental ${\delta}$ values obtained from nonlinear trans -mission measurements, they reasonably predicted the dependence of the ${\delta}$ value on the structural variations. We confirmed the role of molecular symmetry by observing that donor-donor substituted structure gave the highest experimental and theoretical TPA ${\delta}$ values and that the donor-acceptor substituted structure showed a greater red-shift in the TPA absorption maximum wavelength. Overall, the theoretical ${\delta}$ values of DTT-based molecules were in the order of $10^{-46}\;cm^4{\cdot}s{\cdot}photon^{-1}$ and are higher than that of AF-50 by nearly two orders of magnitude.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2145-2148
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• 2012

Objective: This study concerns expression of PBK/TOPK during differentiation of HL-60 leukemic cells induced by tetradecanoyl phorbol acetate (TPA). Methods: Wright-Giemsa staining was performed to observe morphological changes in the HL-60 cells, and flow cytometry was used to assess the cell cycle and CD11b, CD14, CD13, and CD33 expression. PBK/TOPK levels were determined by Western blot analysis. Results: After treating HL60 cells with $5.1{\times}10^{-9}$ mmol/L of TPA for three days, the number of nitroblue-tetrazolium-positive cells and CD11b, CD13, and CD14 expression increased, whereas the PBK/TOPK levels decreased. Conclusions: TPA can inhibit proliferation and induce differentiation of HL60 cells of the granulocytic or monocytic lineage. PBK/TOPK expression was downregulated during this process, whereas the Pho-PBK/TOPK expression was increased.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.94-98
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• 2013

Transfer Path Analysis (TPA) is commonly used, by car makers and parts suppliers, analysis process to root the cause of NVH problems. In general, TPA is an analyzing technique to find the contributing factors of noise/vibration problems, and their transfer path in vehicle. However, not only TPA is used to analyze the source of NVH problems but also is used to predict NVH performance prior to the proto vehicle, or to set the development target for next new vehicle. Automotive parts manufacturing companies have to set NVH performance target when developing new systems just as car makers have NVH target set for new vehicle. Nevertheless, most of components are currently being developed based on subjective evaluation without an objective target. To judge the suitability of using TPA to set NVH target of electric parking brake, this research analyzed the transfer path by setting them in two points of view; Chassis Module and Electric Parking Brake, and comparing the measured value and calculated value. From this result, NVH target of electric parking brake will be approached in level of vehicle, system and component.