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The demand of storing and processing data online grows quickly to adapt to the rapid change of business. It could lead to crisis if the cloud service provider is compromised and data of users are exposed to attackers in plaintext. In this paper, we introduce a practical scheme that dynamically protects and outsources data on demand, as well as propose a corresponding architecture to securely process data in Database Service Provider. After studying over 1300 database models, we believe this scheme can be applied in production with justifiable result.

A femtocell is a small, and low-power cellular base station, typically designed for use in a home or a small business. Since femtocells are likely to be deployed by subscribers individually, we can expect the most of femtocells will be operating as the closed access mode that allows the only authorized users or owners to access the femtocell. Although a lot of femtocells are able to provide the network access covering a large area, they are only used by their owners in the deployed place. This paper addresses the inefficient femtocell operation and proposes a new access mode for femtocells which is called Give-And-Take (GAT) mode. This mode encourages users to share their femtocell access points, and resolve the femtocell inefficiency resulting from the closed access mode. This paper shows that GTA mode can be a feasible solution to improve the femtocell efficiency through a game theory model.

Self-Organizing Map (SOM), one of data mining techniques, has been used as a tool to detect DoS attacks. However, existing SOM-based approaches have the potential drawbacks, the limited detection throughput and vulnerability to DoS attack. Therefore, this paper proposes a new form of SOM, Distributed SOM (DSOM), and shows the feasibility of DSOM through comprehensive experiments.

For an understanding of a heat engine working in the microscopic scale, it is often necessary to estimate the amount of reversible work extracted by isothermal expansion of the quantum gas used as its working substance. We consider an engine with a movable wall, modeled as an infinite square well with a delta peak inside. By solving the resulting one-dimensional Schr\"odinger equation, we obtain the energy levels and the thermodynamic potentials. Our result shows how quantum tunneling degrades the engine by decreasing the amount of reversible work during the isothermal expansion., Comment: 9 pages, 9 figures

In Software Defined Network, the controller is so vulnerable to flooding attack. By injecting spoofed request packets continuously, attackers make a burdensome process to the controller, cause bandwidth occupation in the controller-switch channel, and overload the flow table in switch. The final target of attackers is to downgrade or even shutdown the stability and quality of service of the network. In this paper, we introduce a feasible method to protect the network against Distributed Denial of Service attacks more effectively.

Modeling techniques tend to be found in isolated communities: geometry models in computer-aided design (CAD) and computer graphics, dynamic models in computer simulation, and information models in information technology. When models are included within the same digital environment, the ways of connecting them together seamlessly and visually are not well known even though elements from each model have many commonalities. A model is required to be able to connect models together in the interface; however, creating such models is time-consuming. This article addresses this deficiency by studying specific ways in which models can be interconnected within the same 3D space through effective ontology construction and human interaction techniques. The authors have developed a method for automatically constructing a human-computer interface model (i.e., which is termed an interaction model) from an ontology for an example physical environment. The work to date has resulted in an environment based on a 3D modeling and animation package, permitting users to explore dynamic model structure through interactions with geometric scene structure.

This paper proposes a new method for LQR controller design. It is unsystematic and difficult to design an LQR controller by trial and error. The proposed method is capable of systematically calculating weighting matrices for desired pole(s) by the pole`s moving-range in S-plane and the relational equation between closed-loop pole(s) and weighting matrices. This will provide much-needed functionality to apply LQR controller. The example shows the feasibility of the proposed method.

Although ACK (acknowledgement) should be short since it simply notifies a successful receipt, the actual size of ACK packets increases because of a message header or security options. Especially, in wireless sensor networks where efficiency is the highest priority due to the limited sensor resources, the size of ACK may be reduced by omitting some header fields or security options. However, this pursuit of efficiency can cause security vulnerability such as a faked ACK. In turn, the ACK cannot achieve the original purpose, i.e. to provide reliable communication, any more. Therefore, proposed is a novel ACK message authentication method based on a challenge-response authentication, which can achieve efficiency and security at the same time.

Generation of a quasi-optical single sideband (OSSB) signal for a radio-over-fiber system utilizing the coherent population oscillation effects in a nonlinear semiconductor optical amplifier and transmission over a single-mode fiber (SMF) are investigated. The quasi-OSSB signal generator consists of an electroabsorption modulator and a nonlinear semiconductor optical amplifier. Characteristics of generated quasi-OSSB signals having different radio-frequency (RF) waves (1-50 GHz) transmitted over SMFs of different lengths (4-21 km) were investigated. Bit-error-rate performance of quasi-OSSB signals having 155-Mb/s differential phase-shift keying (DPSK) data transmitted over 0- to 55-km-long SMFs was also evaluated.

TCP (Transport Control Protocol) is the most important protocol in the transport layer of TCP/IP model. TCP works very well in wired network. However, in wireless networks TCP has faced with decrease of performance due to the fact that it treats every packet loss as a congestive loss. In this paper, we propose a new scheme based on TCP Snoop to improve performance of TCP over wireless network. Our scheme efficiently uses Access Point's buffer space by selectively caching policy using fluctuation of Received Signal Strength Indicator (RSSI). Access Point performs local retransmission the cached packets in case corruption loss is detected. By analyzing, the proposed scheme can improve TCP throughput when compare with Snoop in some specific cases.

Background PIN-FORMED (PIN) efflux carriers contribute to polar auxin transport and plant development by exhibiting dynamic and diverse asymmetrical localization patterns in the plasma membrane (PM). Phosphorylation of the central hydrophilic loop (HL) of PINs has been implicated in the regulation of PIN trafficking. Recently, we reported that a phosphorylatable motif (M3) in the PIN3-HL is necessary for the polarity, intracellular trafficking, and biological functions of PIN3. In this study, using the root hair system for PIN activity assay, we investigated whether this motif has been functionally conserved among long-HL PINs. Results Root hair-specific overexpression of wild-type PIN1, 2, or 7 greatly inhibited root hair growth by depleting auxin levels in the root hair cell, whereas overexpression of M3 phosphorylation-defective PIN mutants failed to inhibit root hair growth. Consistent with this root hair phenotype, the PM localization of M3 phosphorylation-defective PIN1 and PIN7 was partially disrupted, resulting in less auxin efflux and restoration of root hair growth. Partial formation of brefeldin A-compartments in these phosphorylation-mutant PIN lines also suggested that their PM targeting was partially disrupted. On the other hand, compared with the PIN1 and PIN7 mutant proteins, M3-phosphorylation-defective PIN2 proteins were almost undetectable. However, the mutant PIN2 protein levels were restored by wortmannin treatment almost to the wild-type PIN2 level, indicating that the M3 motif of PIN2, unlike that of other PINs, is implicated in PIN2 trafficking to the vacuolar lytic pathway. Conclusions These results suggest that the M3 phosphorylation motif has been functionally conserved to modulate the intracellular trafficking of long-HL PINs, but its specific function in trafficking has diverged among PIN members.

Diabetes mellitus (DM) can accompany many musculoskeletal (MSK) diseases. It is difficult to distinguish the DM-related MSK diseases based on clinical symptoms alone. Sonography is frequently used as a first imaging study for these MSK symptoms and is helpful to differentiate the various DM-related MSK diseases. This pictorial essay focuses on sonographic findings of various MSK diseases that can occur in diabetic patients.

A 1.25 Gbps optical baseband (BB) signal in the on-off keying format is frequency up-converted to 60 GHz using wavelength conversion technique by the cross gain modulation (XGM) in a nonlinear semiconductor optical amplifier (NSOA). The 60 GHz frequency up-converted optical radio frequency (RF) signal is simultaneously generated in the form of a quasi optical single sideband (q-OSSB) signal in the NSOA due to the coherent population oscillation (CPO) effects. Bit-error-rate (BER) performance of the 60 GHz frequency up-converted optical radio frequency (RF) signal transmitted over fiber and air channels is investigated.

Error vector magnitude performance of quasi optical single sideband signals with QPSK, 16 QAM, and 32 QAM data generated by coherent population oscillation effects in a semiconductor optical amplifier were investigated.

Cell-based Decentralized Key Management (CDKM) was proposed to manage a group key for secure multicast in mobile cellular networks efficiently. It achieves better performance with less management overhead than other currently available schemes by dividing a group into the cell-based multiple subgroups and delegating key management functions to each base station governing each subgroup. However, room for improvement still remains in the subgroup size affecting the rekeying overhead directly. This paper proposes the enhanced CDKM which improves the rekeying performance through the reduction of the size of the subgroup, and adopts this scheme to group key management in vehicular communication networks. The proposed scheme further splits the cell-based subgroups into several segments, which is simple but very efficient way to reduce the rekeying overhead. We prove mathematically that the additional split enhances the performance, and show the proposed scheme can improve the rekeying performance by up to 15% over the original CDKM and by at least 80% over the existing schemes.

A Mobile Ad-hoc Network (MANET) is actually a set of nodes which are self-configured and organized dynamically. Furthermore, nodes can communicate with each other without any fixed infrastructure as the base stations. The Ad-hoc On demand Distance Vector (AODV) is the most typical reactive routing protocol in MANET. It has been extensively studied through not only computer simulations but also implementations on real network. In this paper, an implementation of AODV routing protocol with multi-metric was presented. In the implementation, an Uppsala University routing protocol, AODVUU was modified in order to apply multi-metrics. Moreover, both AODV-UU and modified AODV-UU were implemented within a Linux-based test bed: a real ad-hoc network. Finally, the performance of both protocols was evaluated experimentally.

A logical key hierarchy (LKH) based key managementapproach is the most common way to manage a group keywith less rekeying overhead. However, the LKH approach causes inefficiency of rekeying the group key in mobile cellular networks since it does not consider the characteristics of the networks, such as the cell-based network topology and the user's mobility. This paper proposes an efficient and practical group key management scheme dedicated to the mobile cellular networks. This new approach can achieve better performance with less management overhead than other currently available schemes, by the cell-based decentralization of key management functions. Through comparisons with other possible approaches, it is shown that the proposed scheme can obtain much better performance in terms of the communication overhead.

Clustering is a representative grouping process to find out hidden information and understand the characteristics of dataset to get a view of the further analysis. The concept of similarity and dissimilarity of objects is a fundamental decisive factor for clustering and the measure of them dominates the quality of results. When attributes of data are categorical, it is not simple to quantify the dissimilarity of data objects that have unimportant attributes or synonymous values. We suggest a new idea to quantify dissimilarity of objects by using distribution information of data correlated to each categorical value. Our method discovers intrinsic relationship of values and measures dissimilarity of objects effectively. Our approach does not couple with a clustering algorithm tightly and so can be applied various algorithms flexibly. Experiments on both synthetic and real datasets show propriety and effectiveness of this method. When our method is applied only to traditional clustering algorithms, the results are considerably improved than those of previous methods.

The Hybrid Wireless Mesh Protocol is a mesh routing protocol that combines the flexibility of on-demand routing with proactive topology tree extensions. The Wireless Mesh Network consists of mesh points and stations. Even if mesh points or stations have mobility, the path should be kept continuously. The Direction of present mobility research is achieved by research in a mobility of stations. In case the MAP moves, this research is very weak. The proposal scheme emphasized in the MAP (Mesh Access Point) mobility. After the Mesh Access Point moves, it re-establishes an existing full path by using the RRER message. However, our scheme is available in an existing path that is changed locally by using a MR (Message Registration) -message which accomplishes locally reestablished path techniques. In this paper, we analyze problems in existent HWMP's path establishment technique.We propose the New Path Selection Scheme by using MR-message produces. Simulation results show that this proposal scheme is designed to reduce packet loss.

The last mile wireless access to 4G networks is inherently vulnerable to various attacks due to broadcasting feature of transmission. Although most wireless communication systems provide the security measures, they focus on the protection of the contents of a message. Therefore, the header part of each message including the source and destination addresses is transmitted in a plain-text format, which can reveal the information that is useful to an attacker. In this paper, we solve the loss of anonymity of the last mile wireless access through a novel pseudonym assignment scheme. Specifically, a master node generates pseudonym sets for slave nodes by using Unique Pair Sequence (UPS) which we first devised, and assigns them to each node. Since every node randomly uses one of pseudonyms in the set as ID whenever it transmits a message, our scheme can prevent an attacker from attempting a traffic analysis attack.

Modeling techniques tend to be found in isolated communities: geometry models in CAD and Computer Graphics and dynamic models in Computer Simulation. When models are included within the same digital environment, the ways of connecting them together seamlessly and visually are not well known even though elements from each model have many commonalities. We attempt to address this deficiency by studying specific ways in which models can be interconnected within the same 3D space through effective ontology construction and human interaction techniques. Our work to date has resulted in an environment built using the open source 3D Blender package, where we include a Python-based interface, as well as scene, geometry, and dynamics models.

Modeling techniques tend to be found in isolated communities: geometry models in CAD and Computer Graphics and dynamic models in Computer Simulation. When models are included within the same digital environment, the ways of connecting them together seamlessly and visually are not well known even though elements from each model have many commonalities. We attempt to address this deficiency by studying specific ways in which models can be interconnected within the same 3D space through effective ontology construction and human interaction techniques.

We present a system called RUBE, which allows a modeler to customize model components and model structure in 2D and 3D. RUBE employs open source tools to assist in model authoring, allowing the user to visualize models with different metaphors. For example, it is possible to visualize an event graph as a city block, or a Petri network as an organically-oriented 3D machine. We suggest that such flexibility in visualization will allow existing model types to take on forms that may be more recognizable to modeling sub-communities, while employing notation as afforded by inexpensive graphical hardware. There is also a possibility to create model types using entirely new notations.

Until fairly recently, the idea of dynamic model content and presentation were treated synonymously. For example, if one was to take a data flow network, which captures the dynamics of a target system in terms of the flow of data through nodal operators, then one would often standardize on rectangles and arrows for the model display. The increasing web emphasis on XML, however, suggests that the network model can have its content specified in an XML language, and then the model can be represented in a number of ways depending on the chosen style. We have developed a formal method, based on styles, that permits a model to be specified in XML and presented in 1D (text), 2D, and 3D. This method allows for customization and personalization to exert their benefits beyond e-commerce, to the area of model structures used in computer simulation. This customization leads naturally to solving the bigger problem of model integration - the act of taking models of a scene and integrating them with that scene so that there is only one unified modeling interface. This work focuses mostly on customization, but we address the integration issue in the future work section.

SimPackJ/S is the JavaScript and Java version of SimPack, which means SimPackJ/S is a collection of JavaScript and Java libraries and executable programs for computer simulations. The main purpose of creating SimPackJ/S is that we allow existing SimPack users to expand simulation areas and provide future users with a freeware simulation toolkit to simulate and model a system in web environments. One of the goals for this paper is to introduce SimPackJ/S. The other goal is to propose translation rules for converting C to JavaScript and Java. Most parts demonstrate the translation rules with examples. In addition, we discuss a 3D dynamic system model and overview an approach to 3D dynamic systems using SimPackJ/S. We explain an interface between SimPackJ/S and the 3D language--Virtual Reality Modeling Language (VRML). This paper documents how to translate C to JavaScript and Java and how to utilize SimPackJ/S within a 3D web environment.

The objective of this study is finding the relationship between interstate highway accident frequencies and geometrics using Ra ndom Parameter Negative Binomial model. Even though it is impossible to take account of the same design criteria to the all segments or corridors on the road in reality, previous research estimated the fixed value of coefficients without considering each segment's characteristic. The drawback of the traditional negative binomial is not to explain the integrated variations in terms of time and the distinct characters specific segment has. This results in under-estimation of the standard error which inflates the t-value and finally, affects the modeling estimation. Therefore, this study tries to find the relationship of accident frequencies with the heterogeneous geometrics using 9-years and 7-interstate highway data in Washington State area. 16-types of geometrics are used to derive the model which is compared with the traditional negative binomial Model to understand which Model is more suitable. In addition, by calculating marginal effect and elasticity, heterogeneous variables' effect to the accidents are estimated. Hopefully, this stu dy will help to estiblish the future policy of geometrics.Key words : Accident model, Random parameter negative binomial regression analysis, Interstate highway geometrics, Heterogeneity초 록이 연구는 확률적 모수를 고려한 음이항회귀분석을 이용하여 고속도로에서의 사고와 기하구조와의 관계를 파악하는데 목적이 있다 . 고속도로에서의 기하구조는 모든 구간에 동일한 설계요소가 적용되기에는 현실적으로 불가능함에도 불구하고 , 지금까지의 연구에서는 모형을 통해 도출되는 계수값이 구간에 설치된 기하구조의 특성에 관계없이 항상 고정된 값으로 추정되어왔다 . 고정된 값을 이용한 일반적인 음이항모형은 시간적변화 또는 각 대상구간이 가지고 있는 고유한 특성에 따른 변화를 통합하여 설명하지 못한다는 단점이 있으며 , 이로 인해 추정된 계수의 표준오차가 과소추정되어 t-값이 부풀려지게 되며, 그 결과 모형의 설명력이 떨어지게 된다. 따라서, 이 연구에서는 워싱턴 주에 위치하고 있는 7개의 고속도로에서 발생한 9년동안의 사고자료 및 기하구조자료를 이용하여 구간별로 상이한 기하구조가 사고에 미치는 영향을 알아보고자 한다 . 총 16개의 기하구조 관련 변수가 모형 도출에 이용되었으며, 기존의 음이항모형과의 비교를 통해 이 연구에서 제시하는 모형이 교통사고와 기하구조와의 관계파악에 더욱 적합함을 보이고자 한다. 그리고, 각 변수의 한계효용 및 탄력성 분석을 통해 이질성을 가지는 기하구조가 사고에 미치는 영향을 제시하고자 한다. 이는 향후 기하구조 관련 정책수립에 도움이 될 것으로 판단된다.검색어 : 사고모형, 확률적 모수를 고려한 음이항회귀분석, 고속도로 기하구조, 이질성Transportation Engineering

An all-optical frequency upconversion technique using a quasi optical single sideband (q-OSSB) signal in a nonlinear semiconductor optical amplifier (NSOA) for radio-over-fiber applications is proposed and experimentally demonstrated. An optical radio frequency signal (f(RF) = 37.5 GHz) in the form of a q-OSSB signal is generated by mixing an optical intermediate frequency (IF) signal (f(IF) = 2.5 GHz) with an optical local oscillator signal (f(LO) = 35 GHz) utilizing coherent population oscillation and cross gain modulation effects in an NSOA. The phase noise, conversion efficiency, spurious free dynamic range (SFDR), and transmission characteristics of the q-OSSB signal are investigated.

A 75-year-old man was admitted with recently developed hiccough and a 1 year history of ataxia. He denied drug overuse, stroke, head trauma and a family history of ataxia. He had hypertension for 10 years. He showed left-sided ptosis, miosis, right-sided hypaesthesia and bilateral limb ataxia, which was more prominent on the left side. He lost balance and leaned to the left side while standing when …

An efficient method for scheduling soft aperiodic tasks in uni-processor real-time systems is presented. Simulation results show that fast average response times can be achieved while the time complexity of the method is O(1).