• Nuclear Engineering and Technology
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• v.41 no.10
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• pp.1223-1234
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• 2009

The outlines of seismic PSA implementation standards and seismic hazard evaluation procedure were shown. An overview of the cause investigation of seismic motion amplification on the Niigata-ken Chuetsu-oki (NCO) earthquake was also shown. Then, the contents for improving the seismic hazard evaluation methodology based on the lessons learned from the NCO earthquake were described. (1) It is very important to recognize the effectiveness of a fault model on the detail seismic hazard evaluation for the near seismic source through the cause investigation of the NCO earthquake. (2) In order to perform and proceed with a seismic hazard evaluation, the Japan Nuclear Energy Safety Organization has proposed the framework of the open deliberation rule regarding the treatment of uncertainty which was made so as to be able to utilize a logic tree. (3) The b-value evaluation on the "Stress concentrating zone," which is a high seismic activity around the NCO hypocenter area, should be modified based on the Gutenberg-Richter equation.

• Elastomers and Composites
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• v.53 no.2
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• pp.86-94
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• 2018

The effect of the NCO index and catalyst type on the thermal stability of poly(urethane-isocyanurate) (PUIR) foams was investigated to identify a method for enhancing the flame resistance of PUIR. PUIR foams were prepared using 4,4-diphenylmethane diisocyanate (MDI) and [(diethylene glycol)adipate]diol, which were synthesized by esterification of adipic acid and diethylene glycol. Dabco K-15, Dabco TMR-30, and Toyocat RX-5 were used as the catalysts for trimerization and gelation. The amount of urea and isocyanurate groups in PUIR was semi-quantitatively determined by normalizing their absorbance with the phenyl absorbance measured by FT-IR. The normalization data showed that Dabco TMR-30 effectively generated isocyanurate groups in PUIR. As a result, Dabco TMR-30 effectively raised the decomposition temperature and increased the 800 K and 900 K residues of the PUIR foam synthesized with an NCO index of 200.

• Proceedings of the IEEK Conference
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• 2001.06e
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• pp.165-168
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• 2001

In this W the complexity of implementation is reduced by the reduction into half of the number of the multiplier in filter structure of the conventional carrier recovery loop, and as the drawback of NCO of the conventional carrier recovery loop wastes a amount of power for the structure of lookup table, We designed the structure of combinational logic without the lookup table. In the comparison with dynamic power of the proposed NCO, the power of NCO with the lookup table is 175${\mu}$W, NCO with the proposed of structure is 24,65${\mu}$W. As if result, it is recognized that about one eight of loss power is reduced In the simulation of carrier recovery loop designed QPSK demodulator, it is known that the carrier phase is compensated.

• Applied Chemistry for Engineering
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• v.4 no.4
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• pp.814-822
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• 1993

To improve the solubility and adhesion strength of diamine-quinone polymers, urethane group was introduced into the polymer backbone. Urethane group containing polymeric diamines(UDA) were prepared firstly by the decarboxylation of the NCO group in NCO terminated prepolymer obtained from the reaction of MDI and 1.6-hexandiol. The reaction mole ratio of NCO/OH was changed from 1.2 to 2.1 to increase the molecular weight of diamine. From the addition reaction of UDA and p-benzoquinone in THF or DMSO solvent, five kinds of urethane group containing diamine/quinone polymers(PUAQ) were prepared according to the diamine used. IR, NMR, UV-visible spectroscopy and GPC were used to characterize the molecular structure and molecular weight of UDAs and PUAQs. Thermal analysis of polymer by DSC and TGA were carried out according to the molecular weight differency. Also solubility test of UDA and PUAQ with 10 different solvents were carried out to predict the coacting property of the polymers.

• Polymer(Korea)
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• v.29 no.5
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• pp.457-462
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• 2005

Polyurethane foams (PUFs) were prepared from polymeric 4,4'-diphenylmethane diisocyanate (PMDI), mixed polyol with OH value of 480, silicone surfactant, three catalysts, and hydrofluorocarbon(HFC) as blowing agent. Balance (PC-8), gelling (33LV), and trimerization (TMR-2) catalysts were used. The effect of the catalysts on the physical properties of PUF with increase of isocyanate (NCO) index and aging time was investigated. The cell size of the PUF with PC-8 and 33LV slightly increased with an increase in NCO index from 100 to 170 but compressive strength did not change significantly. In case of trimerization catalyst, the compressive strength of PUF increased from 8.75 to 1$10.5 kg_f/cm^2$ and the cell size decreased with an increase in NCO index. The compressive strength of the PUF with 33LV increased from 9.21 to $10.15 kg_f/cm^2$ with an increase in aging time. However, there was no detectable change in the compressive strength of PUF with TMR-2. A possible interpretation of the results includes an additional cross-link reaction of non-reacted MDI and FTIR spectrum illustrated the change of NCO peak.

• Proceedings of the Korean Fiber Society Conference
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• 1987.06a
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• pp.69-70
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• 1987

• Convergence Security Journal
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• v.14 no.3_1
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• pp.3-9
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• 2014

NCOs of the amy-navy-air force are the foundation in maintaining, developing and leading the army making manpower aquisition very important. Currently, the operation or the recruitment business is being overlapped by each training institutions leading to uneffectively decreasing the curiosities of the applicants regarding their future. Even though the NCO selection policy is strong in the aspect of retaining uniqueness, use of acquired specialist, and statute revision, it is showing insufficiency in publicizing, selection effectiveness, promotion of peoples' conveniency, and budget reduction. Therefore, if the unification regarding the recruitment of each military sectors are run by the MMA(Military Manpower Administration), which is the institute that is fully responsible for the recruitment duty, it can acquire excellent man power while decreasing effort and resources, provide accurate information to the NCO applicants on time, and provide improved services through the convenient facilities and systems.

• Structural Engineering and Mechanics
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• v.66 no.4
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• pp.465-476
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• 2018

In this paper, a new meta-heuristic optimization method is presented. This new method is named "Numbers Cup Optimization" (NCO). The NCO algorithm is inspired by the sport competitions. In this method, the objective function and the design variables are defined as the team and the team members, respectively. Similar to all cups, teams are arranged in groups and the competitions are performed in each group, separately. The best team in each group is determined by the minimum or maximum value of the objective function. The best teams would be allowed to the next round of the cup, by accomplishing minor changes. These teams get grouped again. This process continues until two teams arrive the final and the champion of the Numbers Cup would be identified. In this algorithm, the next cups (same iterations) will be repeated by the improvement of players' performance. To illustrate the capabilities of the proposed method, some standard functions were selected to optimize. Also, size optimization of three benchmark trusses is performed to test the efficiency of the NCO approach. The results obtained from this study, well illustrate the ability of the NCO in solving the optimization problems.

• Korean Chemical Engineering Research
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• v.48 no.4
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• pp.434-439
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• 2010

NCO terminated polyurethane prepolymers were synthesized from isophorone diisocyanate(IPDI), poly(tetramethyleneglycol)(PTMG) and dimethylol propionic acid(DMPA). Subsequently, aminosilane terminated prepolymers were prepared by capping the NCO groups of polyurethane prepolymers with different moles of aminopropyl triethoxysilane(0~0.02 mole) as a coupling agent. The average particle size of the silylated polyurethane solutions increased with increasing APS content. Also, the prepared coating films showed better thermal stability and pencil hardness than pure waterborne polyurethane.

• Korean Chemical Engineering Research
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• v.49 no.4
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• pp.411-416
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• 2011

NCO terminated polyurethane prepolymers were synthesized from isophorone diisocyanate(IPDI), polycarbonate diol(PCD) and dimethylol propionic acid(DMPA). Subsequently, acrylic terminated prepolymers were prepared by capping the NCO groups of polyurethane prepolymers with different moles of pentaerythritol triacrylate (0~0.024 moles) as a acrylate monomer. The average particle size of the acrylic terminated polyurethane solutions was increased with increasing PETA contents. Also, the prepared coating films showed better abrasion resistance and pencil hardness than pure waterborne polyurethane.