• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.3
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• pp.138-152
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• 2007

A communication system based on DATEX-ASN, an international communication protocol for use in COSMOS, a real-time traffic responsive signal system of Seoul, was developed in this study. Through laboratory experiments, it was identified that some additional rules were necessary for its successful application to COSMOS and thus proper complementary rules were devised. Laboratory experiments were to measure error-rates of monitoring information packet, EOC duration and operating cycle-length errors at different data transmission rates and the results of each experiment were compared each other. The results show that the DATEX-ASN protocol requires a transmission rate of at least 9,600bps which is higher than a transmission rate of 4,800bps required by NTCIP.

• JOURNAL OF ELECTRICAL WORLD
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• s.278
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• pp.64-69
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• 2000

미국과 유럽에서 추진되고 있는 ITS(Intelligent Transport Systems : 고도도로교통시스템) 도로통신에서 취급하는 정보의 정의, 통신방식의 표준화 등의 동향에 대한 개요를 기술한다. 미국에서는 NTCIP(National Transportation Communication for ITS Protocol)라 불리우는 통신프로토콜, 데이터 딕셔너리, 메시지 셋트 등의 표준화가, 유럽에서는 DATEX-Net라는 데이터 교환의 표준화가 추진되고 있다. 이들은 ITS 분야에서의 시스템 간 및 장치간의 상호운용성$\cdot$호환성을 확보하고 통합적으로 ITS를 전개해가기 위한 기반정비의 주요 항목이다. 양자 공히 표준적인 통신프로토콜이 채용되고 있으나 정보내용, 메시지포맷에 대하여는 NTCIP가 ASN.1(Abstract Systax Notation 1)에서 기술한 MIB(Management Information Base)구조를 갖고 있는 한편, Datex-NET는 독자적인 구조의 사전과 EDIFACT(Electronic Data Interchange for Administration Commerce and Transport)에 따른 메시지사양으로 되어 있어 공통성이 없다. 그러나 센터간 통신에 관하여는 미국에서 제안한 DATEX-ASN이라는 표준화 안에 대하여 유럽에서 전향적인 평가를 하고 있어 통일화의 징조가 보이고 있다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.4
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• pp.34-50
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• 2012

This study set out to define a communication environment between an ITS center and field device required to be introduced in the nation in order to guarantee the interoperability, compatibility, and global competitiveness of communication between them in the nation. It also aimed to establish technical and policy plans for its introduction, develop an emulator for information exchange, and apply VMS by way of showing an example, thus testing its validity. First, a standard environment for information exchange between an ITS center and field device required to be introduced in the nation was defined as a dual protocol between DATEX and SNMP. The study also proposed a message definition system including meta-attribution definition and OID introduction. The study then suggested technical and policy plans for its introduction including securing enough feasibility with feedback through a model project of standard introduction, offering education and promotions for the standard in advance, providing methods to introduce and systematically manage OID, developing a hardware standard proper for the information exchange standard, and setting up an integrated management system to introduce a dual protocol.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.71-84
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• 2009

The communication between the center system and the local controller in the Traffic Signal Controller Specification has been specified by a communication line for the exclusive use and the analog modem serial protocol. Therefore, it can't be adapted in the ITS communication network of the TCP/IP protocol being constructed in the local city. The international and domestic ITS device's communication specification has adapted the DATEX-ASN data exchange technique based on the ethernet communication network. So, this study was performed by the purpose of developing the application communication protocol's standard draft based on the TCP/IP communication protocol for the traffic signal controller, to be able to constitute the traffic signal control system in the ITS communication network. The communication format for 23 items of control, status, and database request etc. which are specified in the standard traffic signal controller was developed by appling the DATEX-ASN data interface procedure and structure which are KS ISO X 14827 Part1, 2, ISO/ DIS 15784 Part-3. To test the developed protocol, the application program for the communication items was developed and according to the test result, the encoding and the decoding transection for all communication items was possible.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.3
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• pp.29-41
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• 2013

This study set out to developing data exchange standard between roadside device and traffic information center fitted in a domestic environment by applying international standard ISO 15784. First, we defined message basic concept of 'Dialog' and essential elements should be defined to define the standard message for securing system compatibility by reference ISO 14817 and ISO 14827 Part 1. For defining standard message items exchanged between AVI and traffic information center, we formed Working Group under ITS Standards Technical Committee and analyzed data flow for ITS National Architecture, Standard messages of existing standards, and AVI operation messages actually operated on roadside now. So, we extracted 14 functionally needed messages and defined 28 standard messages adopting 'Dialog' concept. In case of the application protocol for data exchange standards, we defined basic requirements for securing interoperability and interchangeability considering domestic environment by analyzing reference standard of ISO 15784.

• Journal of Yeungnam Medical Science
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• v.28 no.1
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• pp.94-98
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• 2011

One of the most popular types of vaporizer mounting sytems is Selectatec, as it possesses a simple detachment mechanism. Detachable units can loosen between the vaporizer and anesthetic machine, which can cause vapor leakage. A locking system was subsequently developed to prevent this issue; however, we report a case of an unexpected vapor leakage from a locked vaporizer.

• Journal of Veterinary Clinics
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• v.21 no.3
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• pp.270-275
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• 2004

Anesthetic machines may be equipped with either a precision or nonprecision vaporizer. A precision vaporizer is designed to deliver an exact concentration of anesthetic agent. Goldman vaporizer is a low-flow, closed-circle circuit with a low resistance vaporizer, in circuit. Vaporizers used within circle system(VIC) are not usually temperature compensated and this is generally thought to be a disadvantage. As the volatile agent is vaporized, heat is extracted from the liquid and temperature decreases. This cooling of the liquid leads to a decrease in concentration of the anaesthetic agent delivered by the vaporizer. The purpose of this study is to examine the mechanical consistency of the delivery of isoflurane from Goldman vaporizer and precision vaporizer at various gas flow rates and temperatures. And we first studied isoflurane concentration according to room temperature changes delivered by a Goldman vaporizer and precision vaporizer using different gas flow. The room temperature of $15^{\circ}C,$ $20^{\circ}C,$ $28^{\circ}C$ and fresh gas flow rates of 0.5, 1.0, 1.5, 2.0, 3.0 l/min were used. The inspired agent concentration was measured using a Datex-Ohmeda multigas analyzer. As rose in room temperature, the isoflurane concentration of precision vaporizer approximated the dial setting. On the other hand, at a dial setting concentration of 5.0 percent the delivered isoflurane concentration of precision vaporizer was more than the dial setting in high temperature. The isoflurane concentration of precision vaporizer remained constant despite the increase in temperature. The isoflurane concentration of Goldman vaporizer was increased with rise in room temperature and decreased with rise in gas flow.

• The Journal of Korean Medicine
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• v.27 no.3 s.67
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• pp.38-50
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• 2006

Objectives: The aim of this study was to evaluate the effects of Korean ginseng (KG), Korean red ginseng (KRG) and fermented Korean red ginseng (FKRG) extracts on cerebral hemodynamics and to compare distinction of each extract. Methods: Ten healthy male volunteers $(26.0{\pm}1.8yrs)$ participated in the study according to double-blind and cross-over protocols. Each volunteer was blindly administered 500mg of KG, KRG, FKRG extract or placebo (Dextrin). Blinded researchers measured changes of hyperventilation-induced cerebrovascular reactivity (CVR), mean blood flow velocity (MBFV) of middle cerebral arteries (MCAs) and corrected blood flow velocity at $P_{ETCO2}=40mmHg$ (CV40) using transcranial Doppler ultrasound (DWL Co., Germany). Researchers also observed changes of mean blood pressure (MBP), pulse rate (PR) and expiratory $CO_2$ using S/5 Collector (Datex-Ohmeda Co., Finland). The evaluation was performed at basal condition, and repeated at 1, 2, 3, 4 and 5 hours after administration. Results: MBFV and CV40 in the KRG group tended to rise at I hour after administration, while those of the FKRG group tended to rise at 2 hours after administration. CVR increased significantly after 1 hour in the KRG group (p=0.009) and after 2 hours in the FKRG group (p=0.035), respectively. The KG group showed increasing tendency at 4 hours after administration. No group showed significant difference from the placebo in changes of MBP and PR. Conclusions: It is suggested that KG, KRG and FKRG extracts have effects of enhancing CVR and thus of increasing cerebral blood flow in human subjects.

• Tuberculosis and Respiratory Diseases
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• v.44 no.1
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• pp.136-145
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• 1997

Background : Tracheal Gas Insufflation (TGI) is one of the newer ancillary measures in mechanical ventilation employed to enhance carbon dioxide elimination. TGI exerts its effect through reduction of deadspace ventilation, but the factors determining its effect are not well studied yet. Method : The subjects were seven mechanically-ventilated patients ($58.8{\pm}10.6$ yrs) who showed increased physiologic deadspace greater than 60%. After 30 nun of stabilization with 100% oxygen on pressure control ventilation, continuous flow TGI was administered via the insufflation lumen of Hi-Lo Jet Tracheal Tube (Mallincrodt, USA) for 15 min at 3 L/min and 5 L/min each. Results : $PaCO_2$ was decreased ($51.4{\pm}17.6$ at baseline, $49.1{\pm}18.9$ at TGJ 3 L/min $45.0{\pm}14.9$ mm Hg at TGI 5 L/min, p=0.050), and pH was increased ($7.37{\pm}0.12$, $7.38{\pm}0.13$, $7.39{\pm}0.12$, respectively, p=0.037) while mixed expired $CO_2$ ($P_ECO_2$) was not changed significantly from baseline (p=0.336) by TGI. Physiologic deadspace(Vdphy) was decreased ($73.0{\pm}7.9$% at baseline, $69.8{\pm}10.0$% at TGI 3 L/min, and $67.1{\pm}10.1$% at TGI 5 L/min, p=0.015). $AaDO_2$(p=0.147), Vt(p=0.2140), Pmean(p=0.7788) and mean arterial pressure(p=0.4169) were not changed. The correlation between % maximal decrease of Vdphy were r=0.790 with the ratio of baseline Vdana/Vdphy(p=0.035) and r=-0.754 with baseline Vdalv(p=0.050). Conclusion: TGI was effective in reducing $PaCO_2$ and deadspace, and the deadspace-reducing effect was best correlated with baseline anatomic/physiologic deadspace ratio.