• Proceedings of the KIEE Conference
• /
• 2000.07d
• /
• pp.2557-2560
• /
• 2000

The protection system of the nuclear reactor and chemical reactor are representative of PPC(Plant Protection Controller). This PPC must be designed based on reliability as well as concept of safety, which is a failed system go a way of safe. PPC is consist of part of data acquisition, calculator, communication with redundancy, and a voter is important factor of reliability. Because it is serial connected. This paper presents a Design and Analysis of a Voting Mechanism considering Safety for NMR PPC Using EPLD. In the case of digital implementation a coincidence logic(voter) of PPC, it needs CPU and memory, so increase a number of units. Therefore the failure rate and cost is increased. On the contrary when it is designed EPLD or FPGA.

• KSBB Journal
• /
• v.20 no.1 s.90
• /
• pp.18-20
• /
• 2005

Polypropylene carbonate-polyvalerolactone(PPC-PVL) and polyvalerolactone (PVL) produced from exhausted carbon dioxide were degraded by Stenotrophomonas maltophilia separated from soils of waste landfill. The biodegradation was confirmed by FTIR spectrum. PPC-PVL and PVL were degraded $6.6\%,\;12\%$ respectively, at 28 days of pure Stenotrophomonas maltophilia culture.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.1479-1484
• /
• 2009

It is commonly recognized to need performance management for successful construction project. PPC measurement of Last Planner System is one of construction project measurement method. PPC measurement is quantitatively assessment to go through construction, and that is not completely to be trusted when compare a project with another or an individual case work with another in same project. According to, purpose of this study is comparison indicator establishment that compare project with another or an individual case work with another it is not use PPC measurement for quantitatively assessment to go through construction. The procedure of this study is derive of the point at issue of existing PPC measurement for a aim PPC measurement in this study expenditure and select weight about that and it is applied to actually construction.

• Journal of Korean Ophthalmic Optics Society
• /
• v.1 no.2
• /
• pp.49-55
• /
• 1996

Hydrogenated amorphous carbon(a-C:H) films were fabricated by the low-frequency (60Hz) glow discharge of the mixture of methane and hydrogen, and their electrical properties were investigated. We observed that a-C:H films show the persistent photoconductivity(PPC) by illumination of heat-filtered while light for a few seconds. The PPC was about 10 times larger than the annealed dark conductivity. The samples clearly showed metastable characteristics. With increasing illumination times from 1 to 100 min, the annealing activation energy of the PPC was about 0.39eV. The annealing temperature at which the PPC disappeared increasing from $100^{\circ}C$ to $130^{\circ}C$. Illumination longer than 80 min leads to the formation of ${\pi}$ defects and to the decrease of PPC. From these results, we tentatively propose that the states in the ${\pi}$ band act as deep trap centers generating the metastabilities.

• Korean Journal of Construction Engineering and Management
• /
• v.8 no.3
• /
• pp.57-65
• /
• 2007

Last Planner System (LPS) developed by Lean Construction Institute consists of four steps: Master Schedule, Phase Schedule, Lookahead Planning and Weekly Work Plan. This paper focuses on the process of measuring Percent of Plan Completed (PPC) at the weekly Work Plan stage. PPC means the percentage of weekly assignments completed. According to the results of the researches that deal with PPC from many other countries, we can assure the benefits or using PPC. However the concept of PPC is unfamiliar in Korea construction industry. This paper analyzes the cases in which PPC is applied in other countries and compares them with the production control system in Korean construction industry. The results of this research will provide the time management system for using PPC in Korea.

• Radiation Oncology Journal
• /
• v.4 no.1
• /
• pp.45-50
• /
• 1986

RTOG proposed a multivariate modelling system predicting the response of head and neck cancers to radiation therapy in 1984. The aim of this study was to veri(y whether PPC (Probaility of primary clearance calculated by a multivariate modelling system) had any correlation with the survival in the patients with carcinoma of the nasopharynx following radiation therapy Analysing 81 patients with carcinoma of the nasopharynx treated with radiotherapy between January 1, 1971 and December 31, 1983 at Yonsei University College of Medicine, Yonsei Cancer Center the actuarial 5 year survival rate was $36\%$ and median survival was 39 months. The survivals for Group 1 (27 who had more than $80\%$ of PPC), Group 2 (20 who had between 71 and $80\%$ of PPC), and Group 3 (29 who had less than $71\%$ of PPC) were $66\%$ (median survival months : more than 72), $27\%$ (31), and $4\%$ (12) respectively. There was a definite correlation between PPC and survival among the three groups.

• Macromolecular Research
• /
• v.16 no.5
• /
• pp.473-480
• /
• 2008

In this study we investigated bacterial and cell adhesion to poly(propylene carbonate) (PPC) films, that had been synthesized by the copolymerization of carbon dioxide (a global warming chemical) with propylene oxide. We also assessed the biocompatibility and biodegradability of the films in vivo, and their oxidative degradation in vitro. The bacteria adhered to the smooth, hydrophobic PPC surface after 4 h incubation. Pseudomonas aeruginosa and Enterococcus faecalis had the highest levels of adhesion, Escherichia coli and Staphylococcus aureus had the lowest levels, and Staphylococcus epidermidis was intermediate. In contrast, there was no adhesion of human cells (cell line HEp-2) to the PPC films, due to the hydrophobicity and dimensional instability of the surface. On the other hand, the PPC films exhibited good biocompatibility in the mouse subcutaneous environment. Moreover, contrary to expectation the PPC films degraded in the mouse subcutaneous environment. This is the first experimental confirmation that PPC can undergo surface erosion biodegradation in vivo. The observed biodegradability of PPC may have resulted from enzymatic hydrolysis and oxidative degradation processes. In contrast, the PPC films showed resistance to oxidative degradation in vitro. Overall, PPC revealed high affinity to bioorganisms and also good bio-degradability.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.15 no.1
• /
• pp.35-48
• /
• 1993

The in vitro predictive tests in cancer chemotherapy of cancer cell lines to anticancer drugs were determined using novel dye exclusion assay [NDEA], [3H] thymidine incorporation, and clonogenic assay [CA>. Antitumor effect of Bleomycin, Cis-platin, Vinblastine, Methotrexate to HEp-2, B16 cell lines using rapid assays was compared with [CA> in this study. In dye exclusion assay of B l6 cell line, cancer cells were sensitive to Bleomycin at all concentrations, to Vinblastine at the level of peak plasma concentration [PPC], ${\times}1/10$ [PPC](P<0.05). And Bleomycin revealed relatively good cytotoxicity than that of CDDP and vinblastine at ${\times}10$[PPC], (P<0.05). HEp-2 cells were resistive to methotrexate at the level of ${\times}100$[PPC] (P<0.05) In [3H] thymidine incorporation assay, B 16 cells were sensitive to Bleomycin, CDDP, Vinblastine at the level of [PPC], ${\times}10$ [PPC](P<0.01). Dose-dependent drugs of bleomycin, CDDP were more sensitive than Vinblastine at high concentration (P<0.05). In clonogenic assay, HEp-2 cell line was sensitive to three drugs of all concentrations except ${\times}10$ [PPC] of CDDP. B 16 cell line was sensitive to all drugs(P<0,01). In comparison of chemosensitivity tests among three assays, the results were correlated(${\gamma}=0.99$, P<0.05).

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.17 no.1
• /
• pp.19-28
• /
• 1981

Accuracy of the position fix obtained by navigation with Omega in the capacity of worldwide navigation depends on the predicted propagation correction. The authors observe continuously the phase differences of the A-C pair and the A-E pair from April 17 to October 14, 1980, at Busan(35\ulcorner07'. 9N, 129\ulcorner06'. 3E), and analyze the characteristic of daily variation the relation between the theoretical PPC and the measu red PPC to study the accuracy of the position fix. The results are as follows: 1. The results of fourier's analysis for the theoretical PPC and the measured PPC are positive correlation in the coefficients ao, a2, a3 with A-C pair and in the coefficients aO-a3 with A-E pair, and those PPC are apparent to daily periodicity during all measured time. The initial phase is around to 280\ulcorner with A-C pair and 1800 with A-E pair. 2. Daily variatons of the phase difference tend to decrease and the time width to narrow from April toward July, but these variations are opposed to those from July toward October. 3. Mean value of total errors of the position fix by theoretical PPC is 2.67 miles and its standard deviationis O.90miles. 4. Mean value of total errors of the position fix by the measured PPC is 0.63 miles and its standard deviation is 0.217 miles.

• Applied Chemistry for Engineering
• /
• v.24 no.6
• /
• pp.621-627
• /
• 2013

In order to apply eco-friendly poly(propylene carbonate) (PPC) into barrier packaging materials, six different PPC/exfoliated graphite (EFG) nanocomposite films with different EFG were successfully prepared by a solution blending method. Their water sorption behavior was gravimetrically investigated as a function of the EFG content and interpreted with respect to their chemical structure and morphology. The water sorption isotherms were reasonably well fitted by Fickian diffusion model, regardless of morphological heterogeneities. With increasing the EFG content, the diffusion coefficient and water uptake decreased from $12.5{\times}10^{-10}cm^2sec^{-1}$ to $7.2{\times}10^{-10}cm^2sec^{-1}$ and from 8.9 wt% to 4.2 wt%, respectively, which indicates that the moisture resistance capacity of PPC was greatly enhanced by incorporating EFG into PPC. The enhanced water barrier property of the PPC/EFG nanocomposite films with the high aspect ratio EFG makes them potential candidates for versatile packaging applications. However, to maximize the performance of the nanocomposite films, further researches are required to increase the compatibility of EFG in the PPC matrix.