Peom Park

Effect of RObust Header Compression (ROHC) and Packet Aggregation on Multi-hop Wireless Mesh Networks

This paper evaluates the behavioral effect of RObust Header Compression (ROHC) and packet aggregation in multi-hop wireless mesh networks. ROHC itself shows around 20% achieved rate improvement on a line of wireless link even if as the number of mesh router increases, total achieved rate gradually decreases. Packet aggregation cooperating with ROHC provides 4 to 10 times achieved rate improvement and results in maximum 6 times reduction of end-to-end delay. Even if the ROHC and packet aggregation gives such a promising improvement, we need to identify effect of the processing time of the two schemes on overall wireless mesh network behaviors. To do this work, we measure/use ROHC processing time from Pentium 4 and RouterBOARD 230, and apply the results into NS-2 simulations. The simulation results show high performance improvement from ROHC and packet aggregation deteriorates as a general purpose processor in a mesh router takes much time to deal with the two schemes. This result motivates a hardware design be required to speed up the processing units of the two schemes. Consequently, we propose a hardware system model for ROHC and packet aggregation by using SystemC Hardware Description Language (HDL). From the SystemC results, we conclude the proposed built-in processor design for the two schemes keeps performance improvement by enhancing the low speed processing power of general purpose processors.

Comparison of visibility measurement techniques for forklift truck design factors

This study applied the light bulb shadow test, a manikin vision assessment test, and an individual test to a forklift truck to identify forklift truck design factors influencing visibility. The light bulb shadow test followed the standard of ISO/DIS 13564-1 for traveling and maneuvering tests with four test paths (Test Nos. 1, 3, 4, and 6). Digital human and forklift truck models were developed for the manikin vision assessment test with CATIA V5R13 human modeling solutions. Six participants performed the individual tests. Both employed similar parameters to the light bulb shadow test. The individual test had better visibility with fewer numbers and a greater distribution of the shadowed grids than the other two tests due to eye movement and anthropometric differences. The design factors of load backrest extension, lift chain, hose, dashboard, and steering wheel should be the first factors considered to improve visibility, especially when a forklift truck mainly performs a forward traveling task in an open area.

Automation of gross photography using a remote-controlled digital camera system

CONTEXT Conventional gross photography requires a series of tedious and time-consuming steps, including taking, developing, labeling, sorting, filing, and tracking numerous photographs. OBJECTIVE To describe how to automate the gross photographic process by way of controlling a digital camera remotely. DESIGN After defining the requirements of automation regarding gross photography, a remote control board, foot switch, barcode system, and image retrieval system were devised. SETTING The surgical pathology laboratory of a university medical center with a commercially available megapixel digital camera. RESULTS The digital camera zoom and shutter were controlled remotely by a foot switch. A large portion of the gross photographic process, including specimen number labeling, image downloading, labeling, sorting, filing, and tracking, were automated. In addition, the elimination of several manual specimen-processing steps, along with not having to wait for the developing and mounting of conventional 35-mm film, reduced the entire time span required in conventional gross photography from 2 to 5 days, to a few minutes. It was also possible to review the gross images at the time of microscopic sign-out. CONCLUSIONS The automation of gross photography using a remote-controlled digital camera changes the conventional gross workflow markedly. We found use of a remote-controlled gross photography system to be practical, convenient, and efficient.

User required information modality and structure of in-vehicle navigation system focused on the urban commuter

Abstract Current available functions of In-Vehicle Navigation System (IVNS) are approaching to the multimedia system, and its information types become diverse by manufacturing company for accomplishing the on-board multimedia system. Concerning these trends, Human-Machine Interface (HMI) is regarded as more crucial issue for drivers safety and system usability. Also, this kind of issue includes determining the type of information that would be most beneficial to the particular group of users, when and where they need specific information, and the modality in which it should be presented. This paper conducted two kinds of experiments. One is an assessment of drivers mental workload of two kinds of modality to verify the developed Revision of NASA-TLX (RNASA-TLX), and the other is survey-based study to prioritizing the user required information that presented from IVNS. This experiment conducted in the real road situation using IVNS simulator especially focused on the urban commuter.

Prognosis of Glioblastoma With Oligodendroglioma Component is Associated With the IDH1 Mutation and MGMT Methylation Status

Glioblastoma (GBM) with oligodendroglioma component (GBMO) is a newly described GBM subtype in the 2007 World Health Organization classification. However, its biological and genetic characteristics are largely unknown. We investigated the clinicopathological and molecular features of 34 GBMOs and compared the survival rate of these patients with those of patients with astrocytoma, oligodendroglioma, anaplastic oligoastrocytoma (AOA), and conventional GBMs in our hospital. GBMO could be divided into two groups based on the presence of an IDH1 mutation. The IDH1 mutation was more frequently found in secondary GBMO, which had lower frequencies of EGFR amplification but higher MGMT methylation than the wild type IDH1 group, and patients with mutant IDH1 GBMO were on average younger than those with wild-type IDH1. Therefore, GBMO is a clinically and molecularly heterogeneous subtype, largely belonging to a proneural and classical subtype of GBM. The survival rate of GBMO patients itself was worse than that of AOA patients but not significantly better than that of conventional GBM patients. GBMO survival was independent of the dominant histopathological subtype i.e., astrocyte-dominant or oligodendroglioma -dominant, but it was significantly associated with the IDH1 mutation and MGMT methylation status. Therefore, GBMO should be regarded as a separate entity from AOA and must be classified as a subtype of GBM. However, further study is needed to determine whether it is a pathologic variant or a pattern of GBM because GBMO has a similar prognosis to conventional GBMs.

Research of Body Pressure Distribution Change with the Use of BackJoy and Satisfaction of Human Sensibility

Objective: The aim of this study is to investigate the effect of BackJoy on how it effectively reduces the physical load generated in a posture in which the user sits, increases users comfort and satisfaction, and maintains the correct posture. Background: Because of development of science and economic development, most office workers and students spend about 75% of their working time in chairs. However most of them have a poor posture. Method: This experiment conducted measurement using a pressure mat and surveyed to evaluate fatigue level, satisfaction and comfort of sit. The study is experimented 20 male and 14 female participants. The participants carried out four different types of tasks and each task took 20 minutes long. Results: In the case of experiment results before and after the use of BackJoy, average pressure, contact area and pressure per unit area appear to prove that using BackJoy is more effective. Conclusion: Through this study, the BackJoys effects for the maintenance of good posture and loads that occur in the body are reduced. In the future study, there are some researches needed for various verifications using an EMG sensor that shows loads of vertebrae and we need to analyze each group of the participants by dividing them. Application: The evaluation method used in this study can be applied to evaluating ergonomic chairs.

Object Association and Identification in Heterogeneous Sensors Environment

An approach for dynamic object association and identification is proposed for heterogeneous sensor network consisting of visual and identification sensors. Visual sensors track objects by a 2D localization, and identification sensors (i.e., RFID system, fingerprint, or iris recognition system) are incorporated into the system for object identification. This paper illustrates the feasibility and effectiveness of information association between the position of objects estimated by visual sensors and their simultaneous registration of multiple objects. The proposed approach utilizes the object dynamics of entering and leaving the coverage of identification sensors, where the location information of identification sensors and objects is available. We investigate necessary association conditions using set operations where the sets are defined by the dynamics of the objects. The coverage of identification sensor is approximately modeled by the maximum sensing coverage for a simple association strategy. The effect of the discrepancy between the actual and the approximated coverage is addressed in terms of the association performance. We also present a coverage adjustment scheme using the object dynamics for the association stability. Finally, the proposed method is evaluated with a realistic scenario. The simulation results demonstrate the stability of the proposed method against nonideal phenomena such as false detection, false tracking, and inaccurate coverage model.

Dynamic conflict detection and resolution in a human-centered ubiquitous environment

In this paper, a Conflict Control Manager (CCM) for a ubiquitous services system is presented to prevent the mode confusion of humans. CCM consists of a lock-based conflict detection module and a D-PRI (dynamic priority)-based conflict resolution. By means of CCM, the mode confusion can drastically be reduced, and, as a result, CCM can assist in designing and implementing a human-centered ubiquitous environment. Through a case study, it is observed that CCM can successfully detect and resolve the runtime conflicts caused by multiple devices interconnected in a ubiquitous environment. It can also be used to detect the potential conflict risk during the service registering phase so that computerized devices are deployed to improve the human interactions with them.

Tracking an Object in 3-D Space using Particle Filtering based on Sensor Array

This paper presents a formulation of particle filter for tracking an object in 3-D space. The 3-D tracking algorithm is derived based on bearings only tracking algorithm that is applied in tracking of an object in 2-D space with one angle measurement. We investigate and present the fusion process of the algorithms. The performance of the proposed algorithms are evaluated in detail.

U-healthcare Aide System for Ubiquitous Wellbeing Lifecare Smart Space

The purpose of this study is to develop a u-Healthcare aide system as a smart space, which helps health management users to manage their health with precautionary measures. This system consists of three modules: Sensing, Management, and Analysis. The Sensing Module is in charge of measuring, transferring, and receiving vital data. The Management Module helps to offer services for users, medical workers, and managers. This module supports inquiry and analysis and offers the results, meal and exercise prescriptions, and medical pre-examinations. The Analysis Module analyses and predicts diseases and calculates the health index. “u-Health Aide” can meet the needs for social medical service and mitigate the problem of individual medical expenses