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A Study on Development of u-4PL Based Air Cargo Logistics System (항공물류에 적용한 u-4PL 시스템 개발 연구)

  • Li, Guang-Zhu;Na, Hyeong-Seok;Li, Zhong-Shi;Lee, Doo-Yong;Lee, Chang-Ho
    • Proceedings of the Safety Management and Science Conference
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    • 2008.11a
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    • pp.579-582
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    • 2008
  • The wave of 4PL added to strategic consulting based on new IT techniques, for example RFID, with logistics outsourcing through existing 3PL service is a great issue. It is also worthy of notice that EPCglobal network strengthen the role of 4PL. In conclusion, the 4PL system based on EPCglobal network will result in a good success, so it will raise a prestige of air cargo in Korea to a higher position. This study deals with the new logistics system, air cargo logistics system based on u-4PL system, RFID and EPCglobal network, that will bring many advantages.

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Luminescence Properties of InAs/GaAs Quantum Dots Grown by MEE Method (MEE법으로 성장한 InAs/GaAs 양자점의 발광특성)

  • Oh, Jae Won;Byun, Hye Ryoung;Ryu, Mee-Yi;Song, Jin Dong
    • Journal of the Korean Vacuum Society
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    • v.22 no.2
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    • pp.92-97
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    • 2013
  • The luminescence properties of InAs/GaAs quantum dots (QDs) grown by a migration enhanced epitaxy method have been investigated by using photoluminescence (PL) and time-resolved PL measurements. The MEE method supplies materials in a series of alternate depositions with migration enhancing time between each deposition. After In source was supplied for 9.3 s, the growth was interrupted for 5 s. Subsequently, As source was open for 3 (AT3), 4(AT4), 6 (AT6), or 9 s (AT9), and the growth was interrupted for 5 s again. This growth sequence was repeated 3 times for the growth of InAs QDs. The PL peak of the AT3 was 1,140 nm and the PL intensity was very weak compared with that of the other three samples. The PL peak of all samples except the AT3 sample was 1,118 nm, which is blueshifted from 1,140 nm, and the PL intensity was increased compared to that of the AT3. These results can be explained by the increased QD density and the improved QD uniformity. The AT6 sample showed the strongest PL intensity and the narrowest full width at half maximum. The PL decay time of AT6 increased with increasing emission wavelength from 940 to 1,126 nm, reaching a maximum decay time of 1.09 ns at 1,126 nm, and then decreased as the emission wavelength was increased further.

Increased Expression of FosB through Reactive Oxygen Species Accumulation Functions as Pro-Apoptotic Protein in Piperlongumine Treated MCF7 Breast Cancer Cells

  • Park, Jin-Ah;Na, Han-Heom;Jin, Hyeon-Ok;Kim, Keun-Cheol
    • Molecules and Cells
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    • v.42 no.12
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    • pp.884-892
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    • 2019
  • Piperlongumine (PL), a natural alkaloid compound isolated from long pepper (Piper longum), can selectively kill cancer cells, but not normal cells, by accumulation of reactive oxygen species (ROS). The objective of this study was to investigate functional roles of expression of SETDB1 and FosB during PL treatment in MCF7 breast cancer cells. PL downregulates SETDB1 expression, and decreased SETDB1 expression enhanced caspase 9 dependent-PARP cleavage during PL-induced cell death. PL treatment generated ROS. ROS inhibitor NAC (N-acetyl cysteine) recovered SETDB1 expression decreased by PL. Decreased SETDB1 expression induced transcriptional activity of FosB during PL treatment. PARP cleavage and positive annexin V level were increased during PL treatment with FosB overexpression whereas PARP cleavage and positive annexin V level were decreased during PL treatment with siFosB transfection, implying that FosB might be a pro-apoptotic protein for induction of cell death in PL-treated MCF7 breast cancer cells. PL induced cell death in A549 lung cancer cells, but molecular changes involved in the induction of these cell deaths might be different. These results suggest that SETDB1 mediated FosB expression may induce cell death in PL-treated MCF7 breast cancer cells.

Time-resolved Photoluminescence Study of Seven-stacked InAs/InAlGaAs Quantum Dots

  • O, Jae-Won;Gwon, Se-Ra;Ryu, Mi-Lee;Jo, Byeong-Gu;Kim, Jin-Su
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.265-265
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    • 2011
  • 자발형성법으로 InP (001) 기판에 성장한 InAs/InAlGaAs 양자점(QDs: quantum dots)의 광학적 특성을 PL (photoluminescence)와 TRPL (time-resolved PL)을 이용하여 분석하였다. InAs QDs 시료는 single layer InAs QDs (QD1)과 7-stacked InAs QDs (QD2)를 사용하였다. 두 시료 모두 저온 (10 K)에서 1,320 nm에서 PL 피크가 나타나고, 온도가 증가함에 따라 PL 피크는 적색편이 (red-shift)를 보였다. 양자점의 온도를 10 K에서 300 K까지 증가하였을 때 QD1은 178 nm 적색편이 하였으며, PL 스펙트럼 폭은 온도가 증가함에 따라 증가하였다. 그러나 QD2는 264 nm 적색편이를 보였으며 PL 스펙트럼의 폭은 QD1 시료와 반대로 온도가 증가함에 따라 감소하였다. QD2의 아주 넓은 PL 스펙트럼 폭과 매우 큰 적색편이는 InAs 양자점 크기의 변화가 QD1에 비해 훨씬 크기 때문이다. QD2의 경우 InAs 층수(layer number)가 증가함에 따라 InAs QD의 크기가 점차 증가하므로 QD 크기의 변화가 single layer인 QD1 시료보다 훨씬 크다. QD1의 PL 소멸은 파장이 증가함에 따라 점차 느려지다가 PL 피크 근처에서 가장 느린 소멸 곡선을 보이고, 파장이 더 증가하였을 때 PL 소멸은 점차 빠르게 소멸하였다. 그러나 QD2의 PL 소멸곡선은 파장이 증가함에 따라 점차 빠르게 소멸하였다. 이것은 QD2는 양자점 크기의 변화가 매우 크기 때문에 (lateral size=18~29 nm, height=2.8~5.9 nm) 방출파장이 증가함에 따라 양자점 사이의 파동함수의 겹침이 증가하여 캐리어의 이완이 증가하기 때문으로 설명된다. 온도에 따른 TRPL 결과는 두 시료 모두 10 K에서 150 K 까지는 소멸시간이 증가하였고, 150 K 이후부터는 소멸시간이 감소하였다. 온도가 증가함에 따라 소멸시간이 증가하는 것은 양자점에서 장벽과 WL (wetting layer)로 운반자(carrier)의 이동, 양자점들 사이에 열에 의해 유도된 운반자의 재분배 등으로 인한 발광 재결합으로 설명할 수 있다. 150 K 이상에서 소멸시간이 감소하는 것은 열적효과에 의한 비발광 재결합 과정에 의한 운반자의 소멸이 증가하기 때문이다. 온도에 따른 TRPL 결과는 두 시료 모두 150 K까지는 발광재결합이 우세하고, 150 K 이상에서 비발광재겹합이 우세하게 나타났다.

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Visible Photoluminescence from Hydrogenated Amorphous Silicon Substrates by Electron Cyclotron Resonance Plasma Enhanced Chemical Vapor Deposition (ECR-PECVD로 증착한 a-Si : H/Si으로 부터의 가시 PHotoluminescence)

  • Shim, Cheon-Man;Jung, Dong-Geun;Lee, Ju-Hyeon
    • Korean Journal of Materials Research
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    • v.8 no.4
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    • pp.359-361
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    • 1998
  • Visible photoluminescence(PU was observed from hydrogenated amorphous silicon deposited on silicon(a-Si : H/Si) using electron cyclotron resonance plasma enhanced chemical vapor deposition (ECR- PECVD) with silane ($SiH_{4}$) gas as the reactant source. The PL spectra from a-Si : H/Si were very similar to those from porous silicon. Hydrogen contents of samples annealed under oxygen atmosphere for 2minutes at $500^{\circ}C$ by rapid thermal annealing were reduced to 1~2%, and the samples did not show visible PL, indicating that hydrogen has a very important role in the PL process of a- Si : H/Si. As the thickness of deposited a-Si : H film increased, PL intensity decreased. The visi¬ble PL from a-Si: H deposited on Si by ECR-PECVD with $SiH_{4}$ . is suggested to be from silicon hydrides formed at the interface between the Si substrate and the deposited a-Si : H film during the deposition.

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Optical Properties of InAs Quantum Dots Grown by Changing Arsenic Interruption Time (As 차단 시간 변화에 의한 InAs 양자점의 광학적 특성)

  • Choi, Yoon Ho;Ryu, Mee-Yi;Jo, Byounggu;Kim, Jin Soo
    • Journal of the Korean Vacuum Society
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    • v.22 no.2
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    • pp.86-91
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    • 2013
  • The optical properties of InAs quantum dots (QDs) grown on GaAs substrates grown by molecular beam epitaxy have been studied using photoluminescence (PL) and time-resolved PL measurements. InAs QDs were grown using an arsenic interruption growth (AIG) technique, in which the As flux was periodically interrupted by a closed As shutter during InAs QDs growth. In this study, the shutter of As source was periodically opened and closed for 1 (S1), 2 (S2), or 3 s (S3). For comparison, an InAs QD sample (S0) without As interruption was grown in a pure GaAs matrix for 20 s. The PL intensity of InAs QD samples grown by AIG technique is stronger than that of the reference sample (S0). While the PL peaks of S1 and S2 are redshifted compared to that of S0, the PL peak of S3 is blueshifted from that of S0. The increase of the PL intensity for the InAs QDs grown by AIG technique can be explained by the reduced InAs clusters, the increased QD density, the improved QD uniformity, and the improved aspect ratio (height/length). The redshift (blueshift) of the PL peak for S1 (S3) compared with that for S0 is attributed to the increase (decrease) in the QD average length compared to the average length of S0. The PL intensity, PL peak position, and PL decay time have been investigated as functions of temperature and emission wavelength. S2 shows no InAs clusters, the increased InAs QD density, the improved QD uniformity, and the improved QD aspect ratio. S2 also shows the strongest PL intensity and the longest PL decay time. These results indicate that the size (shape), density, and uniformity of InAs QDs can be controlled by using AIG technique. Therefore the emission wavelength and luminescence properties of InAs/GaAs QDs can also be controlled.

Immune Enhancement of Polysaccharide from Submerged Culture with Phellinus linteus in the Medium Supplemented with Ginseng Extract (수삼추출물 첨가 혼합배지에서 조제된 상황 균사체 심부배양물 다당획분의 면역활성 증진)

  • Kim, Hoon;Song, Ki-Yun;Jeong, Jae-Hyun;Jeong, Heon-Sang;Lee, Hyeon-Yong;Yu, Kwang-Won
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.1
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    • pp.20-28
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    • 2011
  • Crude polysaccharide (CP) was fractionated from the submerged culture (containing both mycelia and culture broth, SC) with Phellinus linteus (PL) in mushroom complete medium (MCM) supplemented with ginseng extract ($65^{\circ}$Bx, GE) to enhance the immune activity. PL-GE-15-CP from SC cultivated in MCM supplemented with GE-15% (v/v, a ratio of MCM volume to GE) showed significantly higher macrophage stimulation (1.45 fold of the saline control at $100{\mu}g$/mL) than PL-GE-5 and 10-CP with GE-5 and 10%, or PL-CP from SC without GE. The potent intestinal immune system modulating activity through Peyer's patch was also obtained by PL-GE-15-CP (1.46 fold). When PL-GE-15-CP further fractionated on DEAE-Sepharose CL-6B (Cl- form), PL-GE-15-CP-II was the significantly higher than others from PL-GE-15-CP or PL-CP on macrophage stimulation, interleukin (IL)-12 production and intestinal immune system modulation (1.54, 3.96 and 1.56 fold, respectively). PL-GE-15-CP-II also had higher anti-metastatic activity against colon 26-M3.1 carcinoma cell (57.3% inhibition of tumor control, $200{\mu}g$/mouse) rather than PL-CP-II. This active fraction (PL-GE-15-CP-II) mainly contained neutral sugar (82.45%) and uronic acid (12.99%), and component sugar analysis showed that PL-GE-15-CP-II consisted mainly of uronic acid, Ara, Man, Gal and Glc (molar ratio of 0.52:0.97:0.63:1.00:0.54). Furthermore, the activity of GE culture was higher compared with culture without GE, indicating that GE helped to enhance the immune activity of P. linteus; also, it is assumed that the polysaccharide plays an important role in immune enhancement.

Abstracted Partitioned-Layer Index: A Top-k Query Processing Method Reducing the Number of Random Accesses of the Partitioned-Layer Index (요약된 Partitioned-Layer Index: Partitioned-Layer Index의 임의 접근 횟수를 줄이는 Top-k 질의 처리 방법)

  • Heo, Jun-Seok
    • Journal of Korea Multimedia Society
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    • v.13 no.9
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    • pp.1299-1313
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    • 2010
  • Top-k queries return k objects that users most want in the database. The Partitioned-Layer Index (simply, the PL -index) is a representative method for processing the top-k queries efficiently. The PL-index partitions the database into a number of smaller databases, and then, for each partitioned database, constructs a list of sublayers over the partitioned database. Here, the $i^{th}$ sublayer in the partitioned database has the objects that can be the top-i object in the partitioned one. To retrieve top k results, the PL-index merges the sublayer lists depending on the user's query. The PL-index has the advantage of reading a very small number of objects from the database when processing the queries. However, since many random accesses occur in merging the sublayer lists, query performance of the PL-index is not good in environments like disk-based databases. In this paper, we propose the Abstracted Partitioned-Layer Index (simply, the APL-index) that significantly improves the query performance of the PL-index in disk-based environments by reducing the number of random accesses. First, by abstracting each sublayer of the PL -index into a virtual (point) object, we transform the lists of sublayers into those of virtual objects (ie., the APL-index). Then, we virtually process the given query by using the APL-index and, accordingly, predict sublayers that are to be read when actually processing the query. Next, we read the sublayers predicted from each sublayer list at a time. Accordingly, we reduce the number of random accesses that occur in the PL-index. Experimental results using synthetic and real data sets show that our APL-index proposed can significantly reduce the number of random accesses occurring in the PL-index.

A Study on the Factors of Selecting 3PL Companies by Using CFPR Method in Korea (CFPR법을 활용한 국내 화주기업의 3PL 기업 선정 요인에 관한 연구)

  • Kang, Rae-Hyeon;Yang, Tae-Hyeon;Lee, Hae-Chan;Park, Sung-Hoon;Yeo, Gi-Tae
    • Journal of Digital Convergence
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    • v.18 no.5
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    • pp.169-178
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    • 2020
  • The selection of a third-party logistics (3PL) provider is a critical process for shippers who want to receive competitive logistics service. However, studies analyzing the factors that influence the selection of 3PL provider from the viewpoint of shippers are insufficient. The present study aims to derive factors to be considered when selecting a 3PL provider by domestic shippers and to present the weights of each factor. The analysis results showed that among the major factors, the "operation factor" showed the highest importance, followed by "strategic factor", and "communication factor". The results of compound weights showed that "cost reduction" is the most important factor, followed by the "expertise of the provider", "inventory management ability", and "human resources management". The present study proposed the core factors that should be considered when selecting a 3PL provider from the shipper's viewpoint. This study also has an industrial implication from the viewpoint of 3PL providers because it provides the basic data for enhancing the shipper's satisfaction by reinforcing the factors that are considered important in by shippers. In future research, it is necessary to classify shippers by industry and analyze the differences in the factors that arise in selecting 3PL companies for each industry.

Extracting Priorities of Strategic Components of Product Liability Response System using AHP (AHP기법을 활용한 제조물책임 대응시스템 구축요인의 전략적 우선순위 도출에 관한 연구)

  • JunHyeok, Seo;BokSoo, Ko;Bae, SungMin
    • Journal of Korean Society for Quality Management
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    • v.42 no.2
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    • pp.235-251
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    • 2014
  • Purpose: To develop efficient PL response system, SMEs should decide which component of PL response system is important and implemented with priority under limited resources. To accomplish this goal, we propose strategic priority components of PL response system for SME manufacturer. Methods: We categorize the components of PL response system based on prior research results - System, Organization, Training, Technology, Cost, and Awareness. AHP (Analytic Hierarchy Process) is applied to extract important components of PL response system, which is used in assigning the priority of component. To analyze effects of each components, performance sensitivity analysis is applied. Results: The survey analysis results show Technology is the most important components. Organization and Cost component are follows. As the importance of Technology is changed, we can find Organization, Cost is second and third important components. Conclusion: Our research shows Technology which is related to make a safe product with systematic process, is a basic enabler of PL response system. Also, building a PL team and securing a budget for PL activity should be carry out with limited resources.