• Title, Summary, Keyword: TPR

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A Cost Model for the Performance Prediction of the TPR-tree (TPR-tree의 성능 예측을 위한 비용 모델)

  • 최용진;정진완
    • Journal of KIISE:Databases
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    • v.31 no.3
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    • pp.252-260
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    • 2004
  • Recently, the TPR-tree has been proposed to support spatio-temporal queries for moving objects. Subsequently, various methods using the TPR-tree have been intensively studied. However, although the TPR-tree is one of the most popular access methods in spatio-temporal databases, any cost model for the TPR-tree has not yet been proposed. Existing cost models for the spatial index such as the R-tree do not accurately ostinato the number of disk accesses for spatio-temporal queries using the TPR-tree, because they do not consider the future locations of moving objects. In this paper, we propose a cost model of the TPR-tree for moving objects for the first time. Extensive experimental results show that our proposed method accurately estimates the number of disk accesses over various spatio-temporal queries.

A Performance Study on the TPR*-Tree (TPR*-트리의 성능 분석에 관한 연구)

  • Kim, Sang-Wook;Jang, Min-Hee;Lim, Seung-Hwan
    • Journal of Korea Spatial Information System Society
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    • v.8 no.1
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    • pp.17-25
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    • 2006
  • TPR*-tree is the most widely-used index structure for effectively predicting the future positions of moving objects. The TPR*-tree, however, has the problem that both of the dead space in a bounding region and the overlap among hounding legions become larger as the prediction time in the future gets farther. This makes more nodes within the TPR*-tree accessed in query processing time, which incurs the performance degradation. In this paper, we examine the performance problem quantitatively with a series of experiments. First, we show how the performance deteriorates as a prediction time gets farther, and also show how the updates of positions of moving objects alleviates this problem. Our contribution would help provide Important clues to devise strategies improving the performance of TPR*-trees further.

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A Study on Bottom-Up Update of TPR-Tree for Target Indexing in Naval Combat Systems (함정전투체계 표적 색인을 위한 TPR-Tree 상향식 갱신 기법)

  • Go, Youngkeun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.22 no.2
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    • pp.266-277
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    • 2019
  • In modern warfare, securing time for preemptive response is recognized as an important factor of victory. The naval combat system, the core of naval forces, also strives to increase the effectiveness of engagement by improving its real-time information processing capabilities. As part of that, it is considered to use the TPR-tree in the naval combat system's target indexing because spatio-temporal searches can be performed quickly even as the number of target information increases. However, because the TPR-tree is slow to process updates, there is a limitation to handling frequent updates. In this paper, we present a method for improving the update performance of TPR-tree by applying the bottom-up update scheme, previously proposed for R-tree, to the TPR-tree. In particular, we analyze the causes of overlaps occurring when applying the bottom-up updates and propose ways to limit the MBR expansion to solve it. Our experimental results show that the proposed technique improves the update performance of TPR-tree from 3.5 times to 12 times while maintaining search performance.

Redox Property of Transition Metal Oxides in Catalytic Oxidation (TPR/TPO 실험기법을 이용한 전이금속산화물의 산화-환원 특성 연구)

  • Kim, Young-Ho;Lee, Ho-In
    • Applied Chemistry for Engineering
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    • v.10 no.8
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    • pp.1161-1168
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    • 1999
  • The redox property of oxide materials of the 3rd period transition metals(Cr~Zn), V, Mo, and W was studied with temperature-programmed reduction/temperature-programmed oxidation(TPR/TPO) experiment. The peak temperatures of TPO spectra were equal to or lower than those of TPR spectra. And the peak shapes of TPO spectra were broader than those of TPR ones. The activation energies of TPR/TPO for the oxides of the 3rd period transition metals showed in the range of 33~149 kJ/mol, while for the oxides of V, Mo, and W, they showed relatively higher values. The change of activation energies of TPR/TPO with various metal oxides showed a similar trend to the change of their metal-oxygen bond strengths. The change of activation energies of o-xylene oxidation for various metal oxides was proportional to the difference (${\Delta}E_a$) between the activation energy of TPR and that of TPO. From these results, we concluded that the oxidation of o-xylene over various metal oxide catalysts follows the Mars-van Krevelen mechanism including the surface reduction-oxidation of the metal oxide itself.

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Development of Single-phase Fuzzy TPR for temperature control (온도제어를 위한 단상용 Fuzzy TPR 개발에 관한 연구)

  • Hong, Sung-Hun;Kang, Moon-Sung
    • Proceedings of the KIEE Conference
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    • pp.1053-1055
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    • 1996
  • This paper proposes a Fuzzy TPR having the control function to a TPR used for the conversion of electricity in industrial field. The Fuzzy TPR based on the Fuzzy Logic Control technique is composed of the parts to calculate the low-level value and the high-level value. These values are calculated by error and change in error which are refer to the look-up table. To show the usefulness of the proposed Fuzzy TPR, it is applied to industrial temperature control system. In the results of experiment, we see that the system is able to fast reach steady-state, and for our approach to be robust to external disturbance than the method using the conventional TPR.

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An Indexing Scheme for Predicting Future-time Positions of Moving Objects with Frequently Varying Velocities (속도 변화가 빈번한 이동 객체의 미래 시점 위치 추정에 적합한 색인 기법)

  • Lim, Sung-Chae
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.5
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    • pp.23-31
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    • 2010
  • With the advances in the information technology and mobile communications, we now face increasing demands for various services based on both of position tracking of moving objects and their efficient index scheme. Accordingly, the $TPR^*$-tree, which were proposed for efficiently tracking moving objects and predicting their positions in the future time, has drawn much intention. As the $TPR^*$-tree came from the R-tree that is suitable for indexing static objects, it does not support cheap update costs. Therefore, it seems to be very costly to index moving objects if there are frequent occurrences of node updates caused by continuously changing velocities and positions. If some moving objects with high velocities have node updates, in particular, then the $TPR^*$-tree may suffer from many unnecessary updates in the wide range of tree regions. To avoid such a problem, we propose a method that can keep fast-moving objects in the child nodes of the root node, thereby saving node update costs in the $TPR^*$-tree. To show our performance advantages and retaining $TPR^*$-tree features, we performed some performance experiments using a simulation technique.

Redox Property of Vanadium Oxide and Its Behavior in Cataltic Oxidation

  • 김영호;이호인
    • Bulletin of the Korean Chemical Society
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    • v.20 no.12
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    • pp.1457-1463
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    • 1999
  • Structure and their redox property of the vanadium oxides prepared by decomposing NH₄VO₃ at various temperatures were studied by XRD, SEM, XPS, and temperature programmed reduction/temperature programmed oxidation (TPR/TPO) experiment. All TPR profiles have two sharp peaks in the temperature range 650-750℃, and the area ratio of the two sharp peaks changed from sample to sample. There were three redox steps in TPR/TPO profiles. The oxidation proceeded in the reverse order of the reduction process, and both the reactions proceeded via quite a stable intermediates. The changes of the morphological factor $(I_{(101)}/I_{(010)})$, the ratio of $O_{1S}$ peak area (O$_{1S}$( α)/O$_{1S}$( β)) in the XPS results, and the ratio of hydrogen consumption in TPR profiles with various vanadium oxides showed the distinct relationship between the structural property and their redox property of vanadium oxides. The change of the specific yield of phthalic anhydride with various vanadium oxides showed a very similar trend to those of the peak area ratio in TPR profiles, which meant that the first reduction step related to the partial oxidation of o-xylene on the vanadium oxide catalyst.

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An Efficient MBR Approximation Scheme for Reducing Dead Space of Bounding Rectangles in The TPR-Tree (TPR-트리에서 경계 사각형의 사장 공간을 줄이기 위한 효율적인 MBR 근사 기법)

  • 최석창;송문배;강상원;황종선
    • Proceedings of the Korean Information Science Society Conference
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    • pp.91-93
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    • 2004
  • 이동 객체의 현재와 미래 위치 질의에 최적화된 색인 구조로써 TPR-트리가 있다 TPR-트리는 기존의 공간 색인 구조와 달리 이동 객체와 경계 사각형을 참조 위치와 속도 벡터를 매개 변수로 한 시간에 대한 선형 함수 형태로 모델링 함으로써 갱신 비용을 줄이고 현재 및 가까운 미래 위치 정보의 예측을 가능하도록 한다 . 하지만 TPR- 트리는 시간의 정파에 따라 경계 사각형이 선형적으로 환장됨으로 인해 경계 사각형 내의 객체를 제외한 나머지 공간인 사장 공간과 경계 사각 혈들 간의 겹침 현상을 증가시켜 정의 성능이 떨어진다는 단점을 가진다. 본 논문에서는 질의 성능을 향상시키기 위하여 경계 사각형 내의 이동 객체들이 이동함에 따라 변경되는 최소 경계 사각형 (MBR: Minimim Bounding Rectangle)을 베지어 곡선 함수를 이용하여 근사함으로써 사장 공간을 줄이는 적응 경계 사각형 (ABR: Adaptive Bounding Rectangle) 기법을 제안한다.

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Hydrogen Reduction Characteristics of Ni-based Mixed Oxides: TPR and XRD Study (니켈 기반 혼합 산화물의 수소 환원 특성: TPR 및 XRD 연구)

  • Ryu, Jae-Chun;Cha, Kwang-Seo;Lee, Dong-Hee;Lee, Young-Seak;Park, Chu-Sik;Kim, Young-Ho
    • Transactions of the Korean hydrogen and new energy society
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    • v.21 no.2
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    • pp.89-97
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    • 2010
  • $Al_2O_3$, $TiO_2$, $ZrO_2$, $Al_2O_3-TiO_2$, $Al_2O_3-ZrO_2$, 및 $TiO_2-ZrO_2$ 혼합 산화물을 지지체로 한 Ni 기반 혼합 산화물을 졸-겔법으로 제조하였다. 제조된 혼합 산화물은 1173K에서 열처리 한 후 구조적 특성 변화를 전자현미경 및 X-선 회절 분석을 이용하여 관찰하였으며, 수소를 이용한 승온 환원(TPR; temperature-programmed reduction) 실험을 통하여 1173K 까지 각 시료들의 환원 피크를 비교 고찰하였다. $Al_2O_3$ 또는 $TiO_2$ 가 혼합된 시료의 경우 1173K 에서의 열처리 후 니켈 알루미네이트 또는 니켈 티타네이트와 같은 새로운 결정상의 생성이 관찰되었으나 $ZrO_2$가 혼합된 경우에는 새로운 결정상의 생성이 관찰되지 않았다. TPR 결과에 의하면, $Al_2O_3$ 또는 $TiO_2$를 혼합된 시료의 경우 벌크 NiO의 TPR 결과와는 달리 생성된 새로운 결정상에 기인한 여러 개의 환원 피크가 나타났으나 $ZrO_2$를 혼합한 경우 벌크 NiO와 비슷한 환원 피크를 보였다. TPR 결과를 기초로 Arrhenius plot 으로부터 각 혼합 산화물들의 수소 환원 활성화 에너지를 도출하였다. $ZrO_2$를 지지체로 사용하는 경우 다른 혼합 산화물들보다 지지체로서 안정한 혼합 산화물상을 형성한다는 것을 지시하듯이 상대적으로 가장 낮은 활성화 에너지를 나타냈다.

APP Tail 1 (PAT1) Interacts with Kinesin Light Chains (KLCs) through the Tetratricopeptide Repeat (TPR) Domain (APP tail 1 (PAT1)과 kinesin light chains (KLCs)의 tetratricopeptide repeat (TPR) domain을 통한 결합)

  • Jang, Won Hee;Kim, Sang-Jin;Jeong, Young Joo;Jun, Hee Jae;Moon, Il Soo;Seog, Dae-Hyun
    • Journal of Life Science
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    • v.22 no.12
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    • pp.1608-1613
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    • 2012
  • A conventional kinesin, KIF5/Kinesin-I, transports various cargoes along the microtubule through interaction between its light chain subunit and the cargoes. Kinesin light chains (KLCs) interact with many different cargoes using their tetratricopeptide repeat (TPR) domain, but the mechanism underlying recognition and binding of a specific cargo has not yet been completely elucidated. We used the yeast two-hybrid assay to identify proteins that interact with the TPR domain of KLC1. We found an interaction between the TPR domain of KLC1 and an amyloid precursor protein (APP)-binding protein PAT1 (protein interacting with APP tail 1). The yeast two-hybrid assay demonstrated that the TPR domain-containing region of KLC1 mediated binding to the C-terminal tail region of PAT1. PAT1 also bound to KLC2 but not to kinesin heavy chains (KIF5A, KIF5B, and KIF5C) in the yeast two-hybrid assay. These protein-protein interactions were also observed in the glutathione S-transferase (GST) pull-down assay and by co-immunoprecipitation. Anti-PAT1 antibody as well as anti-APP anti-body co-immunoprecipitated KLC and KHCs associated with PAT1 from mouse brain extracts. These results suggest that PAT1 could mediate interactions between Kinesin-I and APP containing vesicles.