• Title/Summary/Keyword: Alter System

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Prospective of Technology Advances in Intelligent Transport System tying transportation and telecommunication worlds together

  • 이성경
    • The Magazine of the IEIE
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    • v.24 no.2
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    • pp.13-26
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    • 1997
  • Throughout the world in major urban centers, the volume of vehicular traffic on roads continues to increase. ITS provides drivers with traffic information and new routing options on route In order to make them move quickly to their destinations. The higher mobility, the more productivity we gain. The ultimate goal of Intelligent Transport System is to improve mobility. ITS world is broad and quite varied, as demonstrated by ITS user services, their distinct needs, and complex Interactions and synergies. ITS ties the transportation and telecommunication worlds together. The complex world of telecommunications is evolving and expanding rapidly. Especially over the last two decades, the birth and unprecedented growth of wireless is really marvelous and further holds tremendous promise into the future. This wireless and emerging technologies will offer extensive opportunities to handle many ITS user services, and alter many of the traditional paradigms of transportation.

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A Study on a Development of Turbo Decoder for reducing communication error of fire detection system for Marine Vessels (선박용 화재탐지장치의 통신 Error를 감소시키기 위한 Turbo 복호기 개발에 관한 연구)

  • 정병홍;최상학;오종환;김경석
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2000.11a
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    • pp.123-134
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    • 2000
  • In this study, adapted Turbo Coding Algorithm for reducing communication error of fire detection system for marine vessels, especially image transmission. and proposed decoding speed increasing method of Turbo Coding Algorithm. The results are as follows : 1) Confirmed that a Turbo Code is so useful methods for reducing communication error in lots of noise environments. 2) Proposed technology in this study of speed increasing method of Turbo Coding Algorithm proved 2 times speed up effect than normal Turbo Code and communication error reducing as well in the board made by VHDL software & chips of ALTER Company.

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Investigation for Clamping Properties of the Tool Clamping Device Based on the Shape Memory Alloy for Application of a Micro Spindle System (소형 스핀들 시스템 적용을 위한 형상기억합금 기반 공구 클램핑 장치의 체결특성 고찰)

  • Shin, Woo-Cheol;Ro, Seung-Kook;Park, Jong-Kweon;Lee, Deug-Woo;Chung, Jun-Mo
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.16 no.6
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    • pp.9-14
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    • 2007
  • In this paper, a rotating tool clamping device was developed based on a shape memory alloy(SMA) and its feasibility as a tool holder was experimentally explored. The SMA-based device was able to alter clamping to unclamping through temperature control within 1 second. The means and repeatability(${\sigma}$) of the tool clamping force were 185.5N and 6N respectively and its drifts were less than 3% for an hour. Considering the temperature hysteresis of the SMA-based tool clamping device, it is necessary to heat the SMA ring to around $50^{\circ}C$ after tool change to obtain more clamping force.

Adaptive inverse feedback control of periodic noise for systems with nonminimum phase cancellation path (비최소위상 상쇄계를 가진 시스템을 위한 주기소음의 적응 역 궤환 제어)

  • Kim, Sun-Min;Park, Young-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.11a
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    • pp.437-442
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    • 2000
  • An alternative inverse feedback structure for adaptive active control of periodic noise is introduced for systems with nonminimum phase cancellation path. To obtain the inverse model of the nonminimum phase cancellation path, the cancellation path model can be factorized into a minimum phase term and a maximum phase term. The maximum phase term containing unstable zeros makes the inverse model unstable. To avoid the instability, we alter the inverse model of the maximum phase system into an anti-causal FIR one. An LMS predictor estimates the future samples of the noise, which are necessary for causality of both anti-causal FIR approximation for the stable inverse of the maximum phase system and time-delay existing in the cancellation path. The proposed method has a faster convergence behavior and a better transient response than the conventional FX-LMS algorithms with the same internal model control structure since a filtered reference signal is not required. We compare the proposed methods with the conventional methods through simulation studies.

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Privacy-Preserving NFC-Based Authentication Protocol for Mobile Payment System

  • Ali M. Allam
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.5
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    • pp.1471-1483
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    • 2023
  • One of the fastest-growing mobile services accessible today is mobile payments. For the safety of this service, the Near Field Communication (NFC) technology is used. However, NFC standard protocol has prioritized transmission rate over authentication feature due to the proximity of communicated devices. Unfortunately, an adversary can exploit this vulnerability with an antenna that can eavesdrop or alter the exchanged messages between NFC-enabled devices. Many researchers have proposed authentication methods for NFC connections to mitigate this challenge. However, the security and privacy of payment transactions remain insufficient. We offer a privacy-preserving, anonymity-based, safe, and efficient authentication protocol to protect users from tracking and replay attacks to guarantee secure transactions. To improve transaction security and, more importantly, to make our protocol lightweight while ensuring privacy, the proposed protocol employs a secure offline session key generation mechanism. Formal security verification is performed to assess the proposed protocol's security strength. When comparing the performance of current protocols, the suggested protocol outperforms the others.

Stem Cells and Cell-Cell Communication in the Understanding of the Role of Diet and Nutrients in Human Diseases

  • Trosko James E.
    • Journal of Food Hygiene and Safety
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    • v.22 no.1
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    • pp.1-14
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    • 2007
  • The term, "food safety", has traditionally been viewed as a practical science aimed at assuring the prevention acute illnesses caused by biological microorganisms, and only to a minor extent, chronic diseases cause by chronic low level exposures to natural and synthetic chemicals or pollutants. "food safety" meant to prevent microbiological agents/toxins in/on foods, due to contamination any where from "farm to Fork", from causing acute health effects, especially to the young, immune-compromised, genetically-predisposed and elderly. However, today a broader view must also include the fact that diet, perse (nutrients, vitamins/minerals, calories), as well as low level toxins and pollutant or supplemented synthetic chemicals, can alter gene expressions of stem/progenitor/terminally-differentiated cells, leading to chronic inflammation and other mal-functions that could lead to diseases such as cancer, diabetes, atherogenesis and possibly reproductive and neurological disorders. Understanding of the mechanisms by which natural or synthetic chemical toxins/toxicants, in/on food, interact with the pathogenesis of acute and chronic diseases, should lead to a "systems" approach to "food safety". Clearly, the interactions of diet/food with the genetic background, gender, and developmental state of the individual, together with (a) interactions of other endogenous/exogenous chemicals/drugs; (b) the specific biology of the cells being affected; (c) the mechanisms by which the presence or absence of toxins/toxicants and nutrients work to cause toxicities; and (d) how those mechanisms affect the pathogenesis of acute and/or chronic diseases, must be integrated into a "system" approach. Mechanisms of how toxins/toxicants cause cellular toxicities, such as mutagenesis; cytotoxicity and altered gene expression, must take into account (a) irreversible or reversal changes caused by these toxins or toxicants; (b)concepts of thresholds or no-thresholds of action; and (c) concepts of differential effects on stem cells, progenitor cells and terminally differentiated cells in different organs. This brief Commentary tries to illustrate this complex interaction between what is on/in foods with one disease, namely cancer. Since the understanding of cancer, while still incomplete, can shed light on the multiple ways that toxins/toxicants, as well as dietary modulation of nutrients/vitamins/metals/ calories, can either enhance or reduce the risk to cancer. In particular, diets that alter the embryo-fetal micro-environment might dramatically alter disease formation later in life. In effect "food safety" can not be assessed without understanding how food could be 'toxic', or how that mechanism of toxicity interacts with the pathogenesis of any disease.

Performance and Internal Flow Characteristics of an Axial Flow Pump for a Floating Type Water Treatment System (부유식 수처리시스템용 축류펌프의 성능 및 내부유동)

  • Singh, Patrick Mark;Choi, Young-Do
    • The KSFM Journal of Fluid Machinery
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    • v.17 no.3
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    • pp.52-58
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    • 2014
  • The development of efficient systems for water quality improvement for water sources such as lakes, dams and reservoirs has become a necessity to provide not only a cleaner and safer water to the urban society, but also to provide a cleaner and safer environment for the aquatic organisms living in lakes, dams and reservoirs. This study concentrates on the outlet design and internal flow analysis of an axial flow pump used in a floating type water treatment system completely powered by renewable energy source. The treatment system is designed to raise water from depths of about 3~5m up to the water surface where it is naturally mixed with air as it is released back to the reservoir. The outlet of a typical axial flow pump is modified to suit the floating type water mixer. The performance of the axial flow pump is studied by investigating the internal flow of the system. Results show that the change in outlet shape does not alter the performance of the original pump at the maximum efficiency point as long as the cross sectional area of inlet is the same as the outlet. The axial pump for floating type water treatment system has good cavitation performance in the whole flow passage.

Transaction Processing Scheme for Mobile Database Systems (이동 데이터베이스체계를 위한 거래처리 기법)

  • 최용구
    • Journal of the Korea Society of Computer and Information
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    • v.3 no.4
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    • pp.19-26
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    • 1998
  • Mobile database system address information processing based on database system in mobile computing environment. In the mobile database system, when a mobile transaction host enter a other radio coverage area called a cell while processing a transaction, it have to alter the communication network address to new database server. This is called transactional service handoff. This paper propose a transaction processing scheme for providing the proper function of this transactional service handoffs in mobile database system. This scheme apply coordinator migration mechanism which perform the transaction in new database server when posed to be the transaction service handoff. Fially, the proposed scheme will improve system performance by minimizing the tansmission of message for processing the transactions in mobile database system.

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Effect of Sabaeksan and Sabaeksangakaryereuk on the Respiratory System in Experimental Animals (사백산(瀉白散)과 사백산가사려륵(瀉白散加訶藜勒)이 호흡기계(呼吸器系)에 미치는 영향(影響))

  • Lee, Soon-Hoo;Han, Sang-Whan
    • The Journal of Internal Korean Medicine
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    • v.16 no.1
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    • pp.104-129
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    • 1995
  • Sabaeksan and Sabaeksangagaryureuk, a traditional prescription, has been used in Korea for many centuries as a treatment for chronic respiratory disease. The purpose of the present study was to determine the effect of Sabaeksan and Sabaeksangagaryureuk on acetylcholine-induced tracheal smooth muscle contraction in guinea pigs and norepinephrine-induced vascular smooth muscle contraction in pigs. Guinea pig (500g, female) were killed by CO2 exposure and a segment (8-10mm) of the thoracic trachea from each guinea pig and renal artery from each pig were cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of acetylcholine (Ach) and norepinephrine (NE) which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for acetylcholine (10-7-10-4M) and norepinephrine (10-7-10-4M). Contractions of tracheal smooth muscle evoked by Ach ($ED_{50}$) were inhibited significantly by Sabaeksan and Sabaeksangagaryureuk. Propranolol (10-7M) slightly but significantly attenuated the inhibitory effects of Sabaeksan and Sabaeksangagaryureuk. Indomethacin and methylene blue (10-7M) did not significantly alter the inhibitory effect of Sabaeksan and Sabaeksanga-garyureuk. Contractions of vascular smooth muscle evoked by NE (NE50) were inhibited significantly by Sabaeksan and Sabaeksangagaryureuk. Propranolol (10-7M) slightly but significantly attenuated the inhibitory effects of Sabaeksan and Sabaeksangagaryureuk. Indomethacin and methylene blue (10-7M) did not significantly alter the inhibitory effect of Sabaeksan and Sabaeksangagaryureuk. These results indicate that Sabaeksan and Sabaeksangagaryureuk can relax acetylcholine-induced contraction of guinea pig tracheal smooth muscle, and norepinephrine-induced contraction of pig vascular smooth muscle that this inhibition involves, in part, the relation of adrenergic receptor.

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Effectiveness of the Microlux/DLTM Chemiluminescence Device in Screening of Potentially Malignant and Malignant Oral Lesions

  • Ibrahim, Suzan Seif;Al-Attas, Safia Ali;Darwish, Zeinab Elsayed;Amer, Hala Abbas;Hassan, Mona Hassan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.15
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    • pp.6081-6086
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    • 2014
  • Background: To evaluate the effectiveness of Microlux/DL with and without toluidine blue in screening of potentially malignant and malignant oral lesions. Materials and Methods: In this diagnostic clinical trial clinical examination was carried out by two teams: 1) two oral medicine consultants, and 2) two general dentists. Participants were randomly and blindly allocated for each examining team. A total of 599 tobacco users were assessed through conventional oral examination (COE); the examination was then repeated using Microlux/DL device and toluidine blue. Biopsy of suspicious lesions was performed. Also clinicians opinions regarding the two tools were obtained. Results: The sensitivity and, specificity and positive predictive value (PVP) of Microlux/DL for visualization of suspicious premalignant lesions considering COE as a gold standard (i.e screening device) were 94.3%, 99.6% and 96.2% respectively, while they were 100%, 32.4% and 17.9% when considering biopsy as a gold standard. Moreover, Microlux/DL enhanced detection of the lesion and uncovered new lesions compared to COE, whereas it did not alter the provisional clinical diagnosis, or alter the biopsy site. On the other hand, adding toluidine blue dye did not improve the effectiveness of the Microlux/DL system. Conclusions: The Microlux/DL seems to be a promising adjunctive screening device.