• Journal of Communications and Networks
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• 제16권4호
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• pp.415-420
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• 2014

Since the day the Internet became a common and reliable mechanism for communication and data transfer, security officers and enthusiasts rallied to enforce security standards on data transported over the globe. Whenever a user tries communicating with another recipient on the Internet, vital information is sent over different networks until the information is dropped, intercepted, or normally reaches the recipient. Critical information traversing networks is usually encrypted. In order to conceal the sender's identity, different implementations have proven successful - one of which is the invention of anonymous networks. This paper thoroughly investigates one of the most common and existing techniques used during data communication for avoiding traffic analysis as well as assuring data integrity - the onion router (TOR). The paper also scrupulously presents the benefits and drawbacks of TOR.

• Structural Engineering and Mechanics
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• 제56권5호
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• pp.797-811
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• 2015

An analytical-computational method along with finite element analysis (FEA) has been employed to analyse the dynamic behaviour of deteriorated structures excited by time- varying mass. The present analysis is focused on the comparative study of a double cracked beam with inclined edge cracks and transverse open cracks subjected to traversing mass. The assumed computational method applied is the fourth order Runge-Kutta method. The analysis of the structure has been carried out at constant transit mass and speed. The response of the structure is determined at different crack depth and crack inclination angles. The influence of the parameters like crack depth and crack inclination angles are investigated on the dynamic behaviour of the structure. The results obtained from the assumed computational method are compared with those of the FEA for validation and found good agreements with FEA.

• Journal of Institute of Control, Robotics and Systems
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• 제18권3호
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• pp.251-257
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• 2012

Unmanned ground vehicles have important military, reconnaissance, and materials handling application. Many of these applications require the UGVs to move at high speeds through uneven, natural terrain with various compositions and physical parameters. This paper presents a framework for high speed autonomous navigation based on the integrated real time traversability. Specifically, the proposed system performs real-time dynamic simulation and calculate maximum traversing velocity guaranteeing safe motion over rough terrain. The architecture of autonomous navigation is firstly presented for high-speed autonomous navigation. Then, the integrated real time traversability, which is composed of initial velocity profiling step, dynamic analysis step, road classification step and stable velocity profiling step, is introduced. Experimental results are presented that demonstrate the method for a $6{\times}6$ autonomous vehicle moving on flat terrain with bump.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.485-490
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• 2004

Sawtooth mixing device used in a non-premixed burner is evaluated for flame stabilization and NO$_{x}$ reduction. Three mixers with different blade angles are tested. Methane is delivered through the fuel jet and air passes through the co-flow annulus. The flame mode changes (attached flame, lifted flame and extinction) against the fuel flow speed are measured, and the stability diagram is drawn. Moreover, by traversing thermocouple and sampling probe in the flame, the distribution of temperature and NO$_{x}$ mole fraction are measured. With the change in blade angle, flame shape, flame stabilization, the distribution of temperature and NO$_{x}$ mole fraction are changed considerably.rably.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 1999년도 유체기계 연구개발 발표회 논문집
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• pp.234-241
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• 1999

The flow at the impeller exit is important to validate engineering design and numerical analysis of pumps. However, it is not easy to measure the flow at the impeller exit and evaluate the impeller performance since there is usually strong interaction between the impeller and the volute casing. We installed axisymmetric collector instead of the volute casing, so there is no interaction between the impeller and casing. A 3-hole Cobra probe is used to investigate the flow at impeller exit and vaneless diffuser region for design and on design flow rate. For a single suction centrifugal pump of low specific speed, the flow field such as velocity, flow angle, and total pressure are measured by traversing the probe across the vaneless diffuser. These data can be used for performance prediction, desist and numerical analysis of pumps.

• The Transactions of the Korean Institute of Electrical Engineers D
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• 제54권7호
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• pp.447-452
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• 2005

This paper presents a method that a mobile robot finds location of doors in complex environments and safely traverses the door PCA(Principal Component Analysis) algorithm using the vision information is used for a robot to find the location of door, PCA is a useful statistical technique that has found application in fields such as face recognition and image compression, and is a common technique for finding pattern in data of high dimension. Fuzzy controller using a sonar data is used for a robot to avoid obstacles and traverse the doors.

• Proceedings of the KIPE Conference
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• 전력전자학회 2001년도 전력전자학술대회 논문집
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• pp.280-283
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• 2001

The crane operates in three directions, hoisting, traversing, and travelling motion. In this study, an AC drive system for these motions of the crane is developed and tested. The command from an operator is transmitted to PLC, which sends data to a main controller by fieldbus protocols such as Profibus or Devicenet. And the main controller is connected to other auxiliary ones by CAN bus. The each controller, which has the same structure, regulates its motor speed from the operator's command.

• Archives of Plastic Surgery
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• 제32권5호
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• pp.667-670
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• 2005

Congenital facial cleft is a rare entity and appears along by the line of different processes of the facial development. An isolated cleft of the nose has been reported not often in the literature. We treated a patient with an isolated nasal cleft associated with undefined cranial anomaly. On 3D CT scan was seen a bony cleft traversing the pyriform aperture lateral to the anterior nasal spine. The nasal septum and frontal process of the maxilla were intact. There also was found bilateral bony defects in the frontal bone and bilateral frontal boss. The nasal cleft and frontal defect and boss were corrected by two stages: anterior two-third of the cranial vault with bilateral frontal boss was remodeled at the age of two years and the nasal cleft was repaired with a local rotation flap at age 3.

• Transactions of the Korean Society of Mechanical Engineers A
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• 제29권1호
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• pp.14-21
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• 2005

Laser chemical vapor deposition can be an effective technique for a rapid prototyping with ceramic materials, in particular. The objective of the study is to fabricate several 3-dimensional objects by stacking multi-layers as well as to find out some basic aspects of a rapid prototyping with laser chemical vapor deposition such as deposition characteristics with traversing speed of the laser, possible problems in stacking multi-layers etc. The limit speed of the laser that can grow a tilted SiC rod was found in this study, and laser directing writing that occurs over the limit speed was also investigated. Finally, a zigzag-shaped rod, a spiral-shaped rod, a wall and a square duct were successfully fabricated with laser chemical vapor deposition of tetramethylsilane

• Transactions of the Korean Society of Mechanical Engineers
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• 제19권11호
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• pp.3063-3071
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• 1995

An experimental study has been carried out for the heat transfer and particle deposition during the Outside Vapor Deposition process. The surface temperatures of deposited layers, and the rates, efficiencies and porosities of particle deposition were measured. It is shown that the axial variation of the surface temperature can be assumed to be quasi-steady and that as the traversing speed of burner is increased, the deposition rate, efficiency and porosity increase due to the decreased surface temperature. As the flow rate of the chemicals is increased, both the thickness of deposition layers and the surface temperature increase. Deposition rate also increases, however, deposition efficiency decreases for tests done. Later passes in early deposition stage result in higher surface temperatures due to increased thickness of porous deposited layers, which cause the deposition rate, efficiency, and porosity to decrease.