• Title/Summary/Keyword: ppc

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A Study of Evaluation Process and Chart of PPC considering Variation (변이를 고려한 PPC 평가절차 및 평가차트 제안)

  • Moon, Hyo-Gi;Yu, Jung-Ho;Kim, Chang-Duk
    • Korean Journal of Construction Engineering and Management
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    • v.10 no.2
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    • pp.75-83
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    • 2009
  • PPC stands for the percentage of weekly assignments completed. It makes it possible to improve the performance of production planning and control systems. Recently, the cases of PPC application have been increasing because PPC is easy to apply to construction site. However, to evaluate the average of PPC or analyze PPC as time passes has some problem ; if PPC is the same, the average it is evaluated equally although there are variabilities in production system. Therefore, In order to evaluate the character of PPC in process of production this paper suggests the method of the evaluating PPC by using coefficient of variability besides PPC measurement.

Synthesis and Characterization of PPC/Organo-Clay Nanohybrid: Influence of Organically Modified Layered Silicates on Thermal and Water Absorption Properties (PPC와 Organo-Clay 나노 조성물의 합성과 실리카층의 수분흡수와 열적특성에 대한 영향)

  • Han, Hak-Soo;Khan, Sher Bahadar;Seo, Jong-Chul;Jang, Eui-Sung;Choi, Joon-Suk;Choi, Seung-Hyuk
    • Membrane Journal
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    • v.19 no.4
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    • pp.341-347
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    • 2009
  • Nanohybrid based on environmentally friendly and biodegradable polymer, poly propylene carbonate (PPC) and cloisite 20B (PPC/C-20B) have been synthesized by solution blending method and their morphology, thermal and water absorption properties have been evaluated. The structure of PPC/C-20B nanohybrid was confirmed by X-ray diffraction (XRD). The thermal property of PPC and PPC/C-20B nanohybrid were investigated by thermal gravimetric analysis (TGA) and differential scanning calorimetric (DSC). The experimental results demonstrated that nanohybrid showed the highest thermal stability in TGA and DSC. TGA tests revealed that the thermal decomposition temperature ($T_{d50%}$) of the nanohybrid increased significantly, being $23^{\circ}C$ higher than that of pure PPC while DSC measurements indicated that the introduction of 5 mass% of clay increased the glass transition temperature from 21 to $30^{\circ}C$. Further the water absorption capacity of the PPC was significantly decreased by the incorporation of clay. Water absorption cause degradation of the coating by the moistures and affect the physical and mechanical performance. This result indicates that organic modifiers have effect on thermal and water absorption capacity of PPC and are of importance for the practical process and application of PPC.

Evidence of Memory Improvement by Phosphatidylcholine Supplement at Fetus and Neonate -Studies of Basal Forebrain Cholinerge Neuronal Activities- (태생기 및 신생기의 Phosphatidylcholine 보충기 기억력 향상에 미치는 영향 -전뇌기저부의 Choline성 신경세포 활성에 관한 연구-)

  • 전영희
    • Journal of Nutrition and Health
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    • v.32 no.8
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    • pp.864-869
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    • 1999
  • To investigate the effect of dietary phosphatidylcholine(PPC) supplement on memory improvement, biochemical study on the brain, and morphometric studies on the cholinergic neurons in the rat basal forebrain were undertaken. The pregnancy rats were divided into the normal control, the choline deficient and the PPC supplemental groups according to quantity of the PPC in diet. According to choline deficiency and PPC supplement after birth, the neonate rate of the normal control group were subdivided into the control diet(N-N) and the PPC supplied (N-S) groups, the choline deficient group were subdivided into the continually deficient (D-D), the control diet(D-N) and the PPC supplied groups(D-S), and the PPC supplemental group were subdivided into the control diet (S-N)and the continually supplied (S-S)group. The PPC supplemented diet was added 2% egg PPC in AIN 76 formula diet. PPC concentrations and cholinesterase(CE) activities were measured in the serum, the liver and the brain, respectively. Immunohistochemical stains for choline acetyltransferase(ChAT) was employed for the morphological and morphometric studies. The maze test was undertaken to evaluate memory improvement. PPC concentration and CE activities in the serum, liver and the brain were high in the PPC supplemental groups and low in the choline deficient groups. ChAT immunoreactivity neurons at the medial septal diagonal bond complex and the basal forebrain nucleus of Meynert were reduced in the choline deficient groups. Average failure rate for the maze test was the lowest in the S-S group and the highest in the D-D group. Insufficient choline suppley during the neuronal development would result in cholinergic neuronal damage, which could be prevented by adequate PPC supplement. It is consequently suggested that PPC supplement may be effective on memory improvement by maintaining the cholinergic neuronal activity in the basal forebrain of the rats.

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The Method of Improving the Procedure of Time Management for Measuring PPC(Percent of Plan Completed) (작업성취율 측정을 위한 공정관리절차의 개선 방안)

  • Lim, Chul-Woo;Yu, Jung-Ho;Kim, Chang-Duk
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • pp.722-726
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    • 2006
  • 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 of 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.

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Study on the Protective Effect of EGCG Against the Cytotoxicity Induced by Topical Anesthetic Proparacaine Hydrochloride (점안마취제 성분인 Proparacaine Hydrochloride의 세포독성에 대한 Epigallocatechin-Gallate의 효과)

  • Seo, Eun-Sun
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.4
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    • pp.525-531
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    • 2013
  • Purpose: To identify the apoptosis caused by Proparacaine hydrochloride (PPC), a topical anesthesia, applied to conjunctival cell lines and determine whether pigallocatechin-gallate (EGCG), has protective effects on. Methods: The conjunctival cell lines were treated with 0.5% of Alcaine$^{(R)}$, 0.5% of PPC and 0.01% of Benzalkonium chloride (BAC) for 15 minutes, respectively in order to investigate the effects of topical anesthesia on cells, and followed by cultured for 12 and 24 hours. The recovery effects were investigated by measuring level of cellular proliferation inhibiting using MTT assay and LDH assay. The conjunctival cell lines were pre-treated with EGCG $10{\mu}M$ for 3 hrs and post-treated with 0.5% PPC for 15 mins in order to investigate whether EGCG has protective effects, flow cytometry were performed in order to observe apoptosis. Results: A result of the additional culture of 12 and 24 hours and again immediately after the treatment for 15 minutes 0.5% of Alcaine$^{(R)}$, 0.5% of PPC, the 0.01% of BAC, cell viability was not increased in all groups (p<0.05). The cell viabilities were higher than in cells 3 hours post-treated with $10{\mu}M$ of EGCG and pre-treated PPC 0.5% (68.2%), compared to cells ($32.2{\pm}2.0%$) treated only with 0.5% of PPC. PPC 0.5% also induced apoptosis in the treated group was reduced by the addition of EGCG. Conclusions: It is considered that the EGCG has cell protective effects when it is added to PPC, a topical anesthesia, by improving cell viability and inhibiting apoptosis.

Fabrication and Characterization of Environmentally Friendly PLA/PPC/PLA Multilayer Film (친환경 PLA/PPC/PLA 적층필름의 제조 및 특성 연구)

  • Lee, Deuk-Young;Kim, Kyung-Youn;Cho, Misuk;Nam, Jaedo;Lee, Youngkwan
    • Polymer(Korea)
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    • v.37 no.2
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    • pp.249-253
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    • 2013
  • From poly(lactic acid) (PLA) and poly(propylene carbonate) (PPC) synthesized using $CO_2$, a PLA/PPC/PLA layered film is prepared by coextrusion and then stretched to uniaxial orientation. The mechanical, optical, and barrier properties and shrinkage of the prepared film were investigated in detail. The maximum shrinkage of PLA/PPC/PLA film reached to 60% at $75^{\circ}C$. With increasing PPC content, the ratio of shrinkage of the film was increased and its shrinkagerate was increased. The ratio of shrinkage of the film decreased with increasing stretching temperature. The prepared film has oxygen and vapor transmission barrier properties. In this study, the PLA/PPC/PLA film is expected to be commercialized as a environmentally friendly shrinkable film.

A Hybrid Clustering Technique for Processing Large Data (대용량 데이터 처리를 위한 하이브리드형 클러스터링 기법)

  • Kim, Man-Sun;Lee, Sang-Yong
    • The KIPS Transactions:PartB
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    • v.10B no.1
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    • pp.33-40
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    • 2003
  • Data mining plays an important role in a knowledge discovery process and various algorithms of data mining can be selected for the specific purpose. Most of traditional hierachical clustering methode are suitable for processing small data sets, so they difficulties in handling large data sets because of limited resources and insufficient efficiency. In this study we propose a hybrid neural networks clustering technique, called PPC for Pre-Post Clustering that can be applied to large data sets and find unknown patterns. PPC combinds an artificial intelligence method, SOM and a statistical method, hierarchical clustering technique, and clusters data through two processes. In pre-clustering process, PPC digests large data sets using SOM. Then in post-clustering, PPC measures Similarity values according to cohesive distances which show inner features, and adjacent distances which show external distances between clusters. At last PPC clusters large data sets using the simularity values. Experiment with UCI repository data showed that PPC had better cohensive values than the other clustering techniques.

Secure Contents Access Control System in IPTV Flexible-PPC Model (IPTV Flexible-PPC 환경에서의 안전한 콘텐츠 접근 제어 시스템)

  • Kang, Yong-Goo;Lim, Ji-Hwan;Oh, Hee-Kuck
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.21 no.1
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    • pp.93-104
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    • 2011
  • A conditional access system is an essential element in IPTV services enabling service providers to allow authorized access to their services only to paid subscribers. Currently, there are two types of IPTV service models, namely PPC (pay-per-channel) and PPV (pay-per-view). However, a more desirable model would be the flexible PPC model, in which subscribers are free to choose any combination of preferred channels and add/remove channels independently. In this paper, we first point out that a previously proposed key management scheme for F-PPC is not secure. We then propose a new conditional access system using 4-level key hierarchy to realize secure F-PPC services. Compared to existing schemes, the proposed system is very efficient, just requiring O(1) communication for key update.

Nurses' Knowledge of and Attitudes toward Pediatric Palliative Care of Korea (간호사의 소아청소년 호스피스완화의료에 대한 지식 및 태도)

  • Kang, Kyung-Ah;Kim, Hyun Sook;Kwon, So-Hi;Nam, Mi Jung;Bang, Kyung-Sook;Yu, Su Jeong;Jung, Yun;Choi, Sung Eun;Chung, Bok-Yae
    • Journal of Hospice and Palliative Care
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    • v.17 no.4
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    • pp.289-300
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    • 2014
  • Purpose: The aim of this research was to explore nurses' knowledge of and attitudes toward pediatric palliative care (PPC) in Korea. Methods: A descriptive cross-sectional design was used. A total of 196 participants were recruited from the ELNEC-PPC course held in Seoul, Korea. All participants completed a 20-item survey questionnaire which assessed knowledge of and attitudes toward PPC using a 7-point Likert scale. Results: Nurses' knowledge of PPC correlated with their educational level and work experience in the pediatric unit and hospice care unit. The work experience in the pediatric unit, career length in PPC and completion of palliative education course made differences in the attitudes toward PPC. Married nurses scored significantly higher on the parental rights in determining palliative care service for their child, and nurses with master's degree or higher showed a higher level of understanding of and attitudes toward the differences between PPC and adult palliative care. Conclusion: The factors influencing nurses' knowledge of and attitudes toward PPC need be considered to develop a pediatric palliative training program.

Design of a Voting Mechanism considering Safety for NMR PPC Using EPLD and Reliability Analysis (EPLD를 이용한 안전성이 고려된 NMR PPC의 보팅메카니즘 설계와 신뢰도 분석)

  • Ryoo, Dong-Wan;Park, Heui-Youn;Koo, In-Soo;Seo, Bo-Hyeok
    • Proceedings of the KIEE Conference
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    • pp.2557-2560
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    • 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.

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