• Title/Summary/Keyword: Circular Navigation

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Structural Behavior of the Buried flexible Conduits in Coastal Roads Under the Live Load (활하중이 작용하는 해안도로 하부 연성지중구조물의 거동 분석)

  • Cho, Sung-Min;Chang, Yong-Chai
    • Journal of Navigation and Port Research
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    • v.26 no.3
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    • pp.323-328
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    • 2002
  • Soil-steel structures have been used for the underpass, or drainage systems in the road embankment. This type of structures sustain external load using the correlations with the steel wall and engineered backfill materials. Buried flexible conduits made of corrugated steel plates for the coastal road was tested under vehicle loading to investigate the effects of live load. Testing conduits was a circular structure with a diameter of 6.25m. Live-load tests were conducted on two sections, one of which an attempt was made to reinforce the soil cover with the two layers of geo-gird. Hoop fiber strains of corrugated plate, normal earth pressures exerted outside the structure, and deformations of structure were instrumented during the tests. This paper describes the measured static and dynamic load responses of structure. Wall thrust by vehicle loads increased mainly at the crown and shoulder part of the conduit. However additional bending moment by vehicle loads was neglectable. The effectiveness of geogrid-reinforced soil cover on reducing hoop thrust is also discussed based on the measurements in two sections of the structure. The maximum thrusts at the section with geogrid-reinforced soil cover was 85-92% of those with un-reinforced soil cover in the static load tests of the circular structure; this confirms the beneficial effect of soil cover reinforcement on reducing the hoop thrust. However, it was revealed that the two layers of geogrid had no effect on reducing the overburden pressure at the crown level of structure. The obtained values of DLA decrease approximately in proportion to the increase in soil cover from 0.9m to 1.5m. These values are about 1.2-1.4 times higher than those specified in CHBDC.

A Study on Modernization of International Conventions Relating to Aviation Security and Implementation of National Legislation (항공보안 관련 국제협약의 현대화와 국내입법의 이행 연구)

  • Lee, Kang-Bin
    • The Korean Journal of Air & Space Law and Policy
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    • v.30 no.2
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    • pp.201-248
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    • 2015
  • In Korea the number of unlawful interference act on board aircrafts has been increased continuously according to the growth of aviation demand, and there were 55 incidents in 2000, followed by 354 incidents in 2014, and an average of 211 incidents a year over the past five years. In 1963, a number of states adopted the Convention on Offences and Certain Other Acts Committed on Board Aircraft (the Tokyo Convention 1963) as the first worldwide international legal instrument on aviation security. The Tokyo Convention took effect in 1969 and, shortly afterward, in 1970 the Convention for the Suppression of Unlawful Seizure of Aircraft(the Hague Convention 1970) was adopted, and the Convention for the Suppression of Unlawful Acts Against the Safety of Civil Aviation(the Montreal Convention 1971) was adopted in 1971. After 9/11 incidents in 2001, to amend and supplement the Montreal Convention 1971, the Convention on the Suppression of Unlawful Acts Relating to International Civil Aviation(the Beijing Convention 2010) was adopted in 2010, and to supplement the Hague Convention 1970, the Protocol Supplementary to the Convention for the Suppression of Unlawful Seizure of Aircraft(the Beijing Protocol 2010) was adopted in 2010. Since then, in response to increased cases of unruly behavior on board aircrafts which escalated in both severity and frequency,, the Montreal Protocol which is seen as an amendment to the Convention on Offences and Certain Other Acts Committed on Board Aircraft(the Tokyo Convention 1963) was adopted in 2014. Korea ratified the Tokyo Convention 1963, the Hague Convention 1970, the Montreal Convention 1971, the Montreal Supplementary Protocol 1988, and the Convention on the Marking of Plastic Explosive 1991 which have proven to be effective. Under the Tokyo Convention ratified in 1970, Korea further enacted the Aircraft Navigation Safety Act in 1974, as well as the Aviation Safety and Security Act that replaced the Aircraft Navigation Safety Act in August 2002. Meanwhile, the title of the Aviation Safety and Security Act was changed to the Aviation Security Act in April 2014. The Aviation Security Act is essentially an implementing legislation of the Tokyo Convention and Hague Convention. Also the language of the Aviation Security Act is generally broader than the unruly and disruptive behavior in Sections 1-3 of the model legislation in ICAO Circular 288. The Aviation Security Act has reflected the considerable parts of the implementation of national legislation under the Beijing Convention and Beijing Protocol 2010, and the Montreal Protocol 2014 that are the modernized international conventions relating to aviation security. However, in future, when these international conventions would come into effect and Korea would ratify them, the national legislation that should be amended or provided newly in the Aviation Security Act are as followings : The jurisdiction, the definition of 'in flight', the immunity from the actions against the aircraft commander, etc., the compulsory delivery of the offender by the aircraft commander, etc., the strengthening of penalty on the person breaking the law, the enlargement of application to the accomplice, and the observance of international convention. Among them, particularly the Korean legislation is silent on the scope of the jurisdiction. Therefore, in order for jurisdiction to be extended to the extra-territorial cases of unruly and disruptive offences, it is desirable that either the Aviation Security Act or the general Crime Codes should be revised. In conclusion, in order to meet the intelligent and diverse aviation threats, the Korean government should review closely the contents of international conventions relating to aviation security and the current ratification status of international conventions by each state, and make effort to improve the legislation relating to aviation security and the aviation security system for the ratification of international conventions and the implementation of national legislation under international conventions.

Red Ginseng Ameliorates Place Learning Deficits in Aged Rats Young Rats with Selective Hippocampal Lesions

  • Zhong, Yong-Mei;Hisao Nishijo;Teruko Uwano;Hidetishi Yamaguchi;Taketosho Ono
    • Proceedings of the Ginseng society Conference
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    • 1998.06a
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    • pp.1-11
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    • 1998
  • Ameliorating mechanisms of red ginseng on learning deficits were investigated in the following 3 experiments; its effects on 1) place learning deficits in aged rats and in young rats with selective hippocampal lesions (behavioral study), 2) long-term potentiation in the hippocampal formation (neuro- physiological study), and 3) ChAT (choline acetyl transferase) activity in various brain regions of aged rats (pharmacological study). In the behavioral study, first, performance in the place learning tasks were compared among 3 groups of young and aged rats; control young intact rats (10-12 week old) treated with water, aged rats (28-32 month old) treated with water, and aged rats (28-32 month old) treated with red ginseng (100 mghglday) suspended in water. Second, performance in the place learning tasks was compared among 3 groups of young rats; control intact rats treated with water, rats with bilateral hippocampal lesions treated with water, and rats with bilateral hippocampal lesions treated with red ginseng (100 mg/kg/day). Each rat in these 2 behavioral experiments was tested with the 3 types of the place learning tasks in a circular open field using intracranial self-stimulation (ICSS) as reward. The ICSS reward was delivered if the rat (1) moved distance of 100-160 cm (DMT): (2) entered an experiment-determined reward place within the open field, and this place was randomly varied in sequential trials (RRPST); or (3) entered 2 specific places, and did a shuttle behavior between the 2 places (PLT). Performance of the aged rats in the ginseng group was not significantly different from that of control young rats in ICSS (current intensity, bar press rates), DMT and RRPST. However, treatment with red ginseng significantly ameliorated place-navigation learning deficits in aged rats in the PLT. Similarly, red ginseng ameliorated learning and memory deficits in young rats with hippocampal lesions in the same tasks. In the neurophysiological study using young rats, perfusion of hippocampal slices with non-sapon in fraction of red ginseng significantly enhanced magnitudes of the long-term potentiation (LfP) in the CA3 subfield. In the pharmacological study, treatment with red ginseng did not affect ChAT activity in aged rat brain including the hippocampal formation. These results strongly suggest that red ginseng ameliorates learning and memory deficits in aged rats through actions on the CA3 subfield of the hippocampal formation, which were independent of the presynaptic components of the cholinergic system

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Development of Underwater Positioning System using Asynchronous Sensors Fusion for Underwater Construction Structures (비동기식 센서 융합을 이용한 수중 구조물 부착형 수중 위치 인식 시스템 개발)

  • Oh, Ji-Youn;Shin, Changjoo;Baek, Seungjae;Jang, In Sung;Jeong, Sang Ki;Seo, Jungmin;Lee, Hwajun;Choi, Jae Ho;Won, Sung Gyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.3
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    • pp.352-361
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    • 2021
  • An underwater positioning method that can be applied to structures for underwater construction is being developed at the Korea Institute of Ocean Science and Technology. The method uses an extended Kalman filter (EKF) based on an inertial navigation system for precise and continuous position estimation. The observation matrix was configured to be variable in order to apply asynchronous measured sensor data in the correction step of the EKF. A Doppler velocity logger (DVL) can acquire signals only when attached to the bottom of an underwater structure, and it is difficult to install and recover. Therefore, a complex sensor device for underwater structure attachment was developed without a DVL in consideration of an underwater construction environment, installation location, system operation convenience, etc.. Its performance was verified through a water tank test. The results are the measured underwater position using an ultra-short baseline, the estimated position using only a position vector, and the estimated position using position/velocity vectors. The results were compared and evaluated using the circular error probability (CEP). As a result, the CEP of the USBL alone was 0.02 m, the CEP of the position estimation with only the position vector corrected was 3.76 m, and the CEP of the position estimation with the position and velocity vectors corrected was 0.06 m. Through this research, it was confirmed that stable underwater positioning can be carried out using asynchronous sensors without a DVL.

The Need for Modernization of the Tokyo Convention(1963) on the Issue of Unruly Passengers and the Inadequacy of Korean Domestic Legal Approaches (기내 난동승객관련 도쿄협약의 개정필요성과 한국국내법적 접근의 한계)

  • Bae, Jong-In;Lee, Jae-Woon
    • The Korean Journal of Air & Space Law and Policy
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    • v.27 no.1
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    • pp.3-27
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    • 2012
  • Although aviation safety and security have been improving, which has made air transportation more reliable, the international aviation community has witnessed a steady increase in the number of unruly passenger incidents. Under international law, the Tokyo Convention (The Convention on Offences and Certain Other Acts Committed on Board Aircraft of 1963) is applicable to unruly passenger issues. While the Tokyo Convention has been a successful convention which 185 member states have ratified, it has its shortcomings. Three major shortcomings are related to definition, jurisdiction, and enforcement. Firstly, the Tokyo Convention does not provide for a definition of unruly passengers, thereby resulting in a situation where conduct that may be considered to be a criminal offence in the country of embarkation may not be a criminal offence in the country where the aircraft lands. Having different definitions may lead to ineffective action on the part of air carriers. Secondly, the fact that the state of landing does not bear jurisdiction produces circumstances in which it is impossible to punish an unruly passenger who clearly committed an offence on board. Thirdly, the Tokyo Convention only recognizes the competence of the state of registry to exercise criminal jurisdiction but does not impose the duty to actually use that competence in any specific case. Along with ratifying the Tokyo Convention, Korea enacted the Aviation Navigation Safety Act in 1974 as a domestic legal approach to dealing with the problem of unruly passengers. Partially reflecting the ICAO's model legislation, Circular 288, the Aviation Safety and Security Act was enacted in 2002. Although the Korean Aviation Safety and Security Act is a comprehensive act which has been constantly updated, there is no provision with respect to jurisdiction and only the Korean criminal code is applicable to jurisdiction. The Korean criminal code establishes its jurisdiction in connection with territoriality, nationality and registration, which is essentially the same as the jurisdictional principles of the Tokyo Convention. Thus, the domestic legal regime cannot close the jurisdictional gap either. Similarly, Korean case law would not take an active posture to jurisdiction unless the offence in question is a serious one, such as hijacking. A Special Sub Committee of the ICAO Legal Committee (LCSC) was established to examine the feasibility of introducing amendments to the Convention on Offences and Certain Other Acts Committed on Board Aircraft of 1963 with particular reference to the issue of unruly passengers. The result of the ICAO's findings should lead to the modernization of the Tokyo Convention, thereby reducing the number of incidents caused by unruly passengers and enabling all parties concerned to respond to unruly passengers more effectively.

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