• Title/Summary/Keyword: regular action

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Numerical Analysis on Liquefaction Countermeasure of Seabed under Submerged Breakwater using Concrete Mat Cover (for Regular Waves) (콘크리트매트 피복을 이용한 잠제하 해저지반에서의 액상화 대책공법에 관한 수치해석(규칙파 조건))

  • Lee, Kwang-Ho;Ryu, Heung-Won;Kim, Dong-Wook;Kim, Do-Sam;Kim, Tae-Hyung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.28 no.6
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    • pp.361-374
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    • 2016
  • When the seabed around and under gravity structures such as submerged breakwater is exposed to a large wave action long period, the excess pore pressure is generated significantly due to pore volume change associated with rearrangement soil grains. This effect leads a seabed liquefaction around and under structures as a result from decrease in the effective stress, and the possibility of structure failure is increased eventually. These facts shown above have been investigated in the previous studies related to regular and irregular waves. This study suggested a concrete mat for preventing the seabed liquefaction near the submerged breakwater. The concrete mat was mainly used as a countermeasure for scouring protection in riverbed. According to installation of the concrete mattress, the time and spatial series of the deformation of submerged breakwater, the pore water pressure, and the pore water pressure ratio in the seabed were investigated. Their results were also compared with those of the seabed unprotected with the concrete mat. The results presented were confirmed that the liquefaction potential of seabed under the concrete mattress is significantly reduced under regular wave field.

Irregular Waves-Induced Seabed Dynamic Responses around Submerged Breakwater (불규칙파동장하 잠제 주변지반의 동적거동에 관한 수치해석)

  • Lee, Kwang-Ho;Ryu, Heung-Won;Kim, Dong-Wook;Kim, Do-Sam;Kim, Tae-Hyung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.28 no.4
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    • pp.177-190
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    • 2016
  • In case of the seabed around and under gravity structures such as submerged breakwater is exposed to a large wave action long period, the excess pore pressure will be generated significantly due to pore volume change associated with rearrangement soil grains. This effect will lead a seabed liquefaction around and under structures as a result from decrease in the effective stress. Under the seabed liquefaction occurred and developed, the possibility of structure failure will be increased eventually. Lee et al.(2016) studied for regular waves, and this study considered for irregular waves with the same numerical analysis method used for regular waves. Under the condition of the irregular wave field, the time and spatial series of the deformation of submerged breakwater, the pore water pressure (oscillatory and residual components) and pore water pressure ratio in the seabed were estimated and their results were compared with those of the regular wave field to evaluate the liquefaction potential on the seabed quantitatively. Although present results are based on a limited number of numerical simulations, one of the study's most important findings is that a more safe design can be obtainable when analyzing case with a regular wave condition corresponding to a significant wave of irregular wave.

A Study on the Action Potential Generations of the Vestibular Hair Cell Model with Negative Stiffness Feature (반강성 특성이 반영된 전정 유모세포 모델의 활동전위 생성에 관한 연구)

  • Kim, Dongyoung;Hong, Kihwan;Kim, Kyu-Sung;Lee, Sangmin
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.9
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    • pp.190-199
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    • 2014
  • In this paper, the vestibular hair bundle feature model and integrated vestibular hair cell model were proposed. In conventional modeling studies of vestibular system, only partial mechanisms were modeled, such as the characteristics of the vestibular hair bundles without external forces or the action potential of synapse, and the study about action potential of vestibular afferent considering the characteristics of the vestibular hair bundle was not performed. The proposed integrated vestibular hair cell model reflects external forces considering negative stiffness features of each hair bundles with different regularities of hair cells and our model was compared with conventional model without external forces. As a result, irregular afferent and intermediate afferent with high ratio of firing frequency variations to the changes of external stimulation had small width of negative stiffness section, but the width of the negative stiffness of regular afferent with low ratio was similar to that of conventional negative stiffness features. And the proposed integrated vestibular hair cell model showed almost same results with conventional data with animal experiments in 11 chosen frequency bands. It is verified that our proposed hair bundle feature model is adequately modeled.

Electrophysiological and Morphological Classification of Inhibitory Interneurons in Layer II/III of the Rat Visual Cortex

  • Rhie, Duck-Joo;Kang, Ho-Young;Ryu, Gyeong-Ryul;Kim, Myung-Jun;Yoon, Shin-Hee;Hahn, Sang-June;Min, Do-Sik;Jo, Yang-Hyeok;Kim, Myung-Suk
    • The Korean Journal of Physiology and Pharmacology
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    • v.7 no.6
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    • pp.317-323
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    • 2003
  • Interneuron diversity is one of the key factors to hinder understanding the mechanism of cortical neural network functions even with their important roles. We characterized inhibitory interneurons in layer II/III of the rat primary visual cortex, using patch-clamp recording and confocal reconstruction, and classified inhibitory interneurons into fast spiking (FS), late spiking (LS), burst spiking (BS), and regular spiking non-pyramidal (RSNP) neurons according to their electrophysiological characteristics. Global parameters to identify inhibitory interneurons were resting membrane potential (>-70 mV) and action potential (AP) width (<0.9 msec at half amplitude). FS could be differentiated from LS, based on smaller amplitude of the AP (<∼50 mV) and shorter peak-to-trough time (P-T time) of the afterhyperpolarization (<4 msec). In addition to the shorter AP width, RSNP had the higher input resistance (>200 $M{Omega}$) and the shorter P-T time (<20 msec) than those of regular spiking pyramidal neurons. Confocal reconstruction of recorded cells revealed characteristic morphology of each subtype of inhibitory interneurons. Thus, our results provide at least four subtypes of inhibitory interneurons in layer II/III of the rat primary visual cortex and a classification scheme of inhibitory interneurons.

A Study on Countermeasure against Trauma and PTSD of Police Officers -Focused on In-depth Interview with Targets- (경찰공무원의 심리적 외상(Trauma)과 외상후 스트레스 장애(PTSD) 대응 방안에 관한 연구 -대상자 심층면접을 중심으로-)

  • Kang, Gil-Ju;Lee, Sang-Yeol
    • Korean Security Journal
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    • no.56
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    • pp.31-54
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    • 2018
  • The objective of this study is to provide psychological welfare promotion method of police officers who experience trauma and PTSD due to police activity in local community while handling various accidents and protecting civil life and safety at the forefront of the national disaster accident site. For this objective, following countermeasure was presented through trauma/PTSD-related literature and in-depth interview with police officers who experienced trauma and PTSD. First, psychological examination is required to be performed positively and realistically for the police officers. As police officers have high emotional labor stress not only by physical burden but also by civil service, a regular psychological examination shall be established systematically together with physical rest. Second, proper action for the regular psychological examination result of the police officers is required. Third, a psychological support system for the police officers is required to be established and for this objective, expansion of police-operated mindful accompanying center and its devoted operation are required to be performed. Fourth, an opportunity of getting rid of stress of police officers shall be provided and for this objective, required budget for activating club activity is required to be allocated and activity condition should be created.

Hydrodynamic Forces on Fish Cage Systems under the Action of Waves and Current (가두리 시설이 파랑과 흐름에 의해 받는 유체력 특성)

  • Kim, Tae-Ho;Kim, Chang-Gil;Kim, Ho-Sang;Baik, Chul-In;Ryu, Cheong-Ro
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.38 no.3
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    • pp.190-196
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    • 2002
  • In order to analyze the hydrodynamic forces on fish cage systems, made of frames and nettings, under waves and current, hydraulic model experiments for square type and circular type of fish cage system were carried out in a towing tank. Both cage systems consist of net cages supported by floating frames made of two concentric pipes and four weights hanging from the bottom corners of the nets. There was little difference in the hydrodynamic force on the square type of fish cage system by wave heading under regular waves and the peak frequency of the force on each cage system was in a good agreement with that of induced irregular wave. In addition, it was also observed that the circular type of cage system was more stable to the action of waves and current than the square type.

Spreading Processes and Features of School Environmental Education in Korea, the People's Republic of China and Japan (한.중.일 학교 환경교육의 전개와 특색)

  • Suwa, Tetsuo
    • Hwankyungkyoyuk
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    • v.18 no.2 s.27
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    • pp.113-125
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    • 2005
  • Korea, China and Japan show distinct features in their school environmental education, which are derived from their own spreading processes. Japanese school environmental education has developed as a result of assimilating of anti-pollution education and nature education, and has a feature that makes much of nature experiences. The introduction of 'Period for Integrated Study' in 2002 seems to begin activating Japanese school environmental education. Chinese school environmental education started in higher education institutions around the middle of 1970's, and has a feature that makes a point of scientific approach, even in primary education schools. The two government ordinances,'National Action Program for Environmental General Knowledge ($1996{\sim}2010$)' and 'Educational Scheme of Environmental Theme Study for Elementary and Secondary School Students' issued in 2003, gradually promote school environmental education in China. It is remarkable that Science and Technology Centers for Youth and also increasing environmental NPOs often support environmental activities in elementary or secondary schools. The most notable feature of Korean school environmental education is that 'Environment' has already offered as a regular elective subject in junior high school, and official 'Environment' textbook has published since early 1990's. Though, the adoption rate of 'Environment' is not yet so high. Each country's peculiar issues are as follows. Japan: (1) Students often lack basic knowledge about environmental important problems. (2) 'Period for Integrated Study' is now threatened with cutting hours by the idea of increasing periods for basic subjects to keep high achievement. China: (1) There are large regional differences and school distinctions in operation of environmental education. (2) Adult environmental education needs to be expanded, because the most part of Chinese have no experience of school environmental education. Korea: (1) The relationship between the administrative division which plans school environmental education and teachers group is not quite well. The adoption rate of 'Environment' in junior high school needs to be improved. The training of many teachers for environmental education instructors may be the most important and effective cooperative action among Korea, China and Japan, and for that purpose we ought to work on making a better handbook for instructors, at first.

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Primary Closure of Deep Penetrating Wounds under Local Anesthesia with Dental Lidocaine HCL 28 Ampules in Maxillofacial Regions -Report of two cases - (치과용 Lidocaine 28 앰플로 국소마취 하에 1차 봉합한 악안면 심부 관통성 열창 -증례 보고-)

  • Kim, Jong-Bae;Yoo, Jae-Ha
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.1 no.1 s.1
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    • pp.26-31
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    • 2001
  • The wide deep penetrating wound of maxillofacial region should be early closed under emergency general anesthesia for the prevention of complications of bleeding, infection, shock & residual scars. But, if the emergency general anesthesia wound be impossible because of pneumoconiosis, obstructive pulmonary disease & hypovolemic shock, early primary closure should be done under local anesthesia by use of much amount of the anesthetic solution. The maximum dose of dental lidocaine (2% lidocaine with 1 : 100,000 epinephrine) is reported to 7 mg/kg under 500 mg (13.8 ampules) in normal adult. But the maximum permissible dose of dental lidocaine can be changed owing to the general health, rapidity of injection, resorption, distribution & excretion of the drug. The blood level of overdose toxicity is above $4.0{\mu}g/ml$ in central nervous & cardiovascular system. The injection of dental lidocaine 1-4 ampules is attained to the blood level of $1{\mu}g/ml$ in normal healthy adult. The duration of anesthetic action in the dental 2% lidocaine hydrochloride with 1 : 100.000 epinephrine is 45 to 75 minutes and the period to elimination is about 2 to 4 hours. Therefore, authors selected the following anesthetic methods that the first injection of 6 ampules is applied into the deeper periosteal layer for anesthetic action during 1 hour, the second injection into the deeper muscle & fascial layer, the third injection into the superficial muscle and fascial layer, the fourth injection into the proximal skin & subcutaneous tissue and the fifth final injection into the distal skin & subcutaneous tissue. The total 26-28 ampules of dental lidocaine were injected into the wound as the regular time interval during 5-6 hours, but there were no systemic complications, such as, agitation, talkativeness, convulsion and specific change of vital signs and consciousness.

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New Employees' Dietary Attitudes, Nutrition Knowledge, and Food Preferences in Gyeonggi Area (경기지역 사회초년 직장인의 식생활 태도, 영양지식 및 식품 기호도)

  • Jun, Miran;Rhie, Seung Gyo
    • The Korean Journal of Community Living Science
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    • v.26 no.1
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    • pp.39-49
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    • 2015
  • This study evaluates nutrition knowledge, dietary behaviors and food group acceptability based on a sample of 514 of new employees in Gyeonggi area. Among the respondents, 70.6% of male, and their age was 30.7 Most were college graduates (94.9%) and unmarried (86.3%). Based on the BMI males tended to be overweight, whereas females, normal. In terms of health consciousness based on five-point Likert-type scale, the average score for the health status was 4.18 indicating good health, and health attention was 4.88 indicating high health attention. Dietary behaviors were evaluated using five-point Likert-type scale. According to the results, the total score for regular diet based on 5 items was 9.6; that for a balanced diet based on 7 items was 22.2; and that for practical diet action based on 8 items was 22.3. That is, the respondents were on an irregular diet but tried to balanced diet through appropriate diet action. Food acceptability was evaluated using a five-point Likert scale ranging from "strongly dislike(1)" to "strongly like(5)". The score of meat group was 3.67; that for the fish 3.43; and that for the vegetable group was 2.86. Females were slightly more like to accept fruits 3.60 than males 3.48;(p<0.05). The total score for nutrition knowledge based on 35 items was 20.5. A balanced diet was correlated with egg acceptability (p<0.01); energy-related knowledge with confectionery preferences (p<0.05); and vitamin knowledge, with snack affinity (p<0.05). Health attention was negatively correlated with seafood preferences for male(p<0.05) and with snacks for females(p<0.05). The respondents were strongly interested in and aware of their health, but this did not lead to their food preferences. These results suggests that dietary habits can lead to nutritional balance for maintaining the health of employees.

A Neural Network-based Artificial Intelligence Algorithm with Movement for the Game NPC (게임 NPC를 위한 신경망 기반의 이동 안공지능 알고리즘)

  • Joe, In-Whee;Choi, Moon-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.12A
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    • pp.1181-1187
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    • 2010
  • This paper proposes a mobile AI (Artificial Intelligence) conducting decision-making in the game through education for intelligent character on the basis of Neural Network. Neural Network is learned through the input/output value of the algorithm which defines the game rule and the problem solving method. The learned character is able to perceive the circumstances and make proper action. In this paper, the mobile AI using Neural Network has been step-by-step designed, and a simple game has been materialized for its functional experiment. In this game, the goal, the character, and obstacles exist on regular 2D space, and the character, evading obstacles, has to move where the goal is. The mobile AI can achieve its goals in changing environment by learning the solution to several problems through the algorithm defined in each experiment. The defined algorithm and Neural Network are designed to make the input/output system the same. As the experimental results, the suggested mobile AI showed that it could perceive the circumstances to conduct action and to complete its mission. If mobile AI learns the defined algorithm even in the game of complex structure, its Neural Network will be able to show proper results even in the changing environment.