• Title/Summary/Keyword: Sound Power

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Influence of Carbonation on the Chloride Diffusion in Concrete (탄산화 현상이 콘크리트 중의 염소이온 확산에 미치는 영향 연구)

  • Oh, Byung-Hwan;Lee, Sung-Kyu;Lee, Myung-Kue;Jung, Sang-Hwa
    • Journal of the Korea Concrete Institute
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    • v.15 no.6
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    • pp.829-839
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    • 2003
  • Recently, the corrosion of reinforced concrete structures has received great attention related with the deterioration of sea-side structures, such as new airport, bridges, and nuclear power plants. In this regards, many studies have been done on the chloride attack in concrete structures. However, those studies were confined mostly to the single deterioration due to chloride only, although actual environment is rather of combined type. The purpose of the present study is, therefore, to explore the influences of carbonation to chloride attack in concrete structures. The test results indicate that the chloride penetration is more pronounced than the case of single chloride attack when the carbonation process is combined with the chloride attack. It is supposed that the chloride ion concentration of carbonation region is higher than the sound region because of the separation of fixed salts. Though the use of fly ash pronounces the chloride ion concentration in surface, amounts of chloride ion penetration into deep region decreases with the use of fly ash. The present study allows more realistic assessment of durability for such concrete structures which are subjected to combined attacks of both chlorides and carbonation but the future studies for combined environment will assure the precise assessment.

The Perception of Teachers in Scienced-Gifted Education, Science-Gifted Students and their Parents about Science and Scientist (영재지도교사, 영재학생 및 학부모의 과학 및 과학자에 대한 인식)

  • Sim, Byeongju;Yoon, Heesook
    • Journal of Gifted/Talented Education
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    • v.23 no.5
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    • pp.715-729
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    • 2013
  • The purpose of this study is to analyze the perception on science and scientists of the teachers who are engaged in the special education for the scientifically gifted, science-gifted students and their parents. For this study, 34 teachers, 222 students and 107 parents answered the questionnaire of the perception on science and Draw-A-Science-Test (DAST). The result showed that the three groups generally had a sound recognition but the score of recognition about a 'nature of science' was lower than other domains. The science-gifted students had less cognition about 'science and society' than their teachers and parents, but they had more positive perception about 'science learning' than their parents significantly. All of the three groups had the stereotyped image of scientist. About the internal images of scientists, three groups had a similar perception, and they showed higher scores in the cognitive aspect than emotional or ethical aspects. And the science-gifted students showed the significantly higher scores than their teachers and parents in diligence, imaginative power, concern about other people, respect for other's opinion, humor, artistic sense, respect for human, desire for peace. Three groups turned out to be influenced by movie, science journal, and biography as a source of scientist's image, but their contribution was different among groups.

Selection of Auditory Icons in Ship Bridge Alarm Management System Using the Sensibility Evaluation (감성평가를 이용한 선교알람관리시스템의 청각아이콘 평가)

  • Oh, Seungbin;Jang, Jun-Hyuk;Park, Jin Hyoung;Kim, Hongtae
    • Journal of Navigation and Port Research
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    • v.37 no.4
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    • pp.401-407
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    • 2013
  • In parallel with the development of ship equipment, bridge systems have been improved, but marine accidents due to human error have not been reduced. Recently, research in nautical bridge equipment has focused on suitable ergonomic designs in order to reduce these errors due to human factors. In a bridge of a ship, there are numerous auditory signals that deliver important information clearly to the sailors. However, only a few studies have been conducted related to the human recognition of these auditory signals. There are three types of auditory signals: voice alarms, abstract sounds, and auditory icons. This study was conducted in order to design more appropriate auditory icons using a sensibility evaluation method. The auditory icons were rated to have five warning situations (engine failure, fire, steering failure, low power, and collision) using the Semantic Differential Method. It is expected that the results of this study will be used as basic data for auditory displays inside bridges and for integrated bridge alarm systems.

An Overview on China's Recent Air Pollution Regulation and Management Policy (중국의 최근 대기오염 규제 및 관리 정책에 대한 고찰)

  • Choi, Min Uk
    • Environmental and Resource Economics Review
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    • v.27 no.3
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    • pp.569-611
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    • 2018
  • Rapid economic growth, urbanization, and industrialization of China have tremendously degraded the overall quality of living environments, especially the air quality, not only negatively affecting Chinese people but also impacting citizens of neighboring countries, namely Korea. The Chinese government has invested much effort to regulate the air pollution due to burning coal through introducing strict environmental monitoring policies and aggressive implementation. This paper presents an overview of Chinese air pollution prevention policy due to burning coal, and the associated trends and specifics of institutional arrangements regarding air pollutant emission regulations. It turns out that the policies have become stricter than before; some polices are geared towards enforcing extra regulation at the regional level. It is expected that the regulation will become stricter in the future. However, the actual contribution and feasibility of such policies must be analyzed based on sound science. The policies seem to care little about influencing the air quality of Korea, and this has to be improved. In order to do so, it is important to strengthen environmental cooperation between Korea and China, and better yet to research on not only the air quality but also the associated fields, such as energy, industrial technology, and global environmental governance.

Action Types and Responsibility (행위유형과 책임문제 - 행위분석도를 통해 본 책임부여문제 -)

  • Sohn, Kyung-sang
    • Journal of Korean Philosophical Society
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    • v.116
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    • pp.181-206
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    • 2010
  • It is widely recognized that human beings have moral responsibility for their actions because they have free will to choose and control their acts. Unlike natural phenomena, however, human acts cannot be interpreted with simple, visible ones. Human acts are quite different from natural phenomena because they come about through a number of complicated, invisible phases taking place in our mind. In addition, human actions are under the influence of internal and external factors. Those various internal and external factors are divided into four sectors as follows; (1) the factors that can fall under control of our free will, (2) the factors in the interim phase that could come under our control, (3) the factors that are partially determined that we cannot choose or control over, and (4) the factors that completely determined, and can't be chosen or controlled. we have to pay attention to the fact that we can choose or control the internal and external factors that influence human action. However, there are still factors that are impossible to choose or control with our will. So it is highly unreasonable to hold accountable for actors by means of the factors that can't be chosen or controlled. Hence, the society should be also accountable for the acts of actors influenced by heredity and environment. For this, Politics should affect the external, undesirable, and uncontrollable factors beyond actors power. Education has to exert its influence over the internal and genetic factors by instilling sound values in human mind, too. It is because happy and desirable future will be possible by giving equal opportunities to us including the youth.

Eco-friendliness Evaluation of a Low-Noise and Dust-Recovery Type Pavement Cutter (저소음·분진회수형 도로절단기의 친환경성 평가)

  • Kim, Kyoon Tai
    • Ecology and Resilient Infrastructure
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    • v.8 no.4
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    • pp.194-203
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    • 2021
  • With the recent increase in maintenance works on water and sewer pipes as well as district heating supply pipes, pavement cutting work using pavement cutter is on the rise. The pavement cutting operation generates considerable dust (cutting sludge) as well as noise; therefore, it is necessary to apply eco-friendly technologies that have low noise and dust recovery capability. Thus far, various equipment for recovering dust have been developed; however, there is a limitation in that the environmental friendliness is not quantified. Therefore, in this study, we developed a low-noise, dust-recovery type pavement cutter that can fundamentally remove the causes of environmental hazards such as noise and dust and evaluated the eco-friendliness of the pavement cutting process performed by this cutter. To this end, an integrated water cooling-sludge recovery system composed of a vacuum device and a sludge suction unit was developed, and the developed system was applied to a pavement cutter. Subsequently, the developed equipment was applied to the test bed, and data related to its eco-friendliness were collected and evaluated. The results showed that the cutting sludge recovery rate of the developed equipment was greater than 83%, the noise level was approximately 82 - 83 dB, and the sound power level was 115 dB. The results of this study will be used as basic data to develop improved pavement cutters in the future with improved cutting sludge recovery performance and lower noise.

The Development Aspects of Korean Political Theatre Movement (한국 정치극의 전개 양상 - 1920년대부터 80년대까지의 정치극운동을 중심으로 -)

  • Kim, Sung-Hee
    • Journal of Korean Theatre Studies Association
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    • no.52
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    • pp.5-59
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    • 2014
  • This paper investigates the development and aesthetics of Korean political theatre from its quickening period 1920s to democratization era 1990s. Political theatre before 90s developed an antithesis resistant movement toward Korean modern history that had been scattered with suppressing political circumstances such as colonial era and dictatorial government, the movement has powerful activity and social influences. Just like the 20 century political theatre had been quickened under the influence of Marxism at Russia and Germany in 1920s, Korea's political theatre began in socialism theatre movement form around the same time. Proletarian theatre groups had been founded in Japan and Korea, and developed into practical movement with organized connection. However, the political theatre movement in Japanese colonial era was an empty vessel makes great sound but not much accomplishments. Most performance had been canceled or disapproved by suppression or censorship of the Japanese Empire. The political theatre in liberation era was the left drama inherited from Proletarian theatre of the colonial era. Korean Theatre alliance took lead the theatrical world unfold activities based on theatre popularization theory such as 'culture activists' taking a jump up the line and 'independent theatre' peeping into production spot as well as the important event, Independence Movement Day Memorial tournament theatre. Since 1947, US army military government in Korea strongly oppressed the left performances to stop and theatrical movement was ended due to many left theatrical people defection to North Korea. The political theatre in 1960s to 70s the Park regime, developed in dramatically different ways according to orthodox group and group out of power. The political theatre of institutional system handled judgment on sterile people and had indirect political theatre from that took history material and allegory technique because of censorship. In political theatre out of institution, it started outdoor theatre that has modernized traditional performance style and established deep relationship with labor spot and culture movement organizations. Madangguek(Outdoor theatre) is 'Attentive political theatre', satirizing and offending the political and social inconsistencies such as the dictatorial government's oppression and unbalanced distribution, alienation of general people, and foreign powers' pillage sharply as well as laughing at the Establishment with negative characters. The political theatre in 1980s is divided into two categories; political theatre of institutional system and Madangguek. Institutional Political theatre mainly performed in Korea Theatre Festival and the theatre group 'Yeonwoo-Moudae' led political theatre as private theatre company. Madangguek developed into an outdoor theatrical for indoor theatre capturing postcolonial historical view. Yeonwoo-Moudae theatre company produced representative political plays at 80s such as The chronicles of Han's, Birds fly away too, and so on by combining freewheeling play spirit of Madangguek and epic theatre. Political theatre was all the rage since the age of democratization started in 1987 and political materials has been freed from ban. However, political theatre was slowly declined as real socialism was crumbling and postmodernism is becoming the spirit of the times. After 90s, there are no more plays of ideology and propaganda that aim at politicization of theatre. As the age rapidly entered into the age of deideology, political theatre discourse also changed greatly. The concept 'the political' became influential as a new political possibility that stands up to neoliberalism system in the evasion of politics. Rather than reenact political issues, it experiments new political theatre that involves something political by deconstructing and reassigning audience's political sense with provocative forms, staging others and drawing discussion about it.

A Study on Stabilization of Underwater TAS Winch System Deploy/Recover Operation Performance (수중용 TAS윈치 전개/회수 성능 안정화 방안에 관한 연구)

  • Chang, Ho-Seong;Cho, Kyu-Lyong;Hwang, Jae-Gyo;Lee, Sang-Yong;Kim, Yong-Tae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.6
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    • pp.472-482
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    • 2019
  • This paper describes the stabilization of underwater TAS winch system Deploy/Recover operation performance. TAS winch installed on the stern of submarine performs to deploy/recover sensor, towing cable and rope tail which is deployed from the stern and separated from submarine itself. Also TAS winch provides transmission path of power to the sensor and data transmitting/receiving path which data are acquired from underwater environment like sound, depth and temperature. At the step of TAS winch evaluation test, sporadic standstill and rotating speed oscillation phenomenon were occurred. Winch motor provides the available torque to deploy/recover TAS and root cause analysis to the winch motor was done to find exact reason to sporadic malfunction. When winch motor was disassembled, eccentricity of rotor, slip-ring and the other composition part for winch motor were found. These might cause magnetic field distortion. To make TAS winch system more stable and block magnetic field distortion, this paper suggests methods to enhance fixing status installed in winch motor. For reliable data acquisition for TAS winch operation, the deploy/recover function of the improved type of TAS winch was verified in LBTS making similar condition with sea status. At the end of stage, improved type of TAS winch was tested on some functions not only deploy/recover function, but sustainability of TAS operation on specific velocity, steering angle of submarine in the sea trial. Improved type of TAS winch was verified in accordance with design requirement. Also, validity of suggested methods were verified by the sea trial.

Factors Influencing the Retention Intention of Nurses in General Hospital Nurses (종합병원 간호사의 재직의도에 영향을 미치는 요인)

  • Kim, Yu-Mi;Seo, Minjeong
    • Journal of Digital Convergence
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    • v.18 no.12
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    • pp.377-387
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    • 2020
  • The purpose of this study is a descriptive research study to identify the emotional labor, ethical climate, job satisfaction, and retention intention of nurses in general hospitals, and to identify the relationship between variables and factors influencing the retention intention. The study subjects were 198 nurses working in four general hospitals, and data were collected from September 18 to September 30, 2019 using a structured questionnaire. The collected data were analyzed by t-test, ANOVA, Pearson's correlation coefficients, and multiple regression using SPSS WIN 25.0. As a result of the study, there was a positive correlation between ethical climate(r=.345, p<.001) and job satisfaction(r=.388, p<.001), but emotional labor (r=-.153, p=.031) showed negative correlation. Factors influencing the retention intention of general hospital nurses are job satisfaction(β=.27, p=.001), age(β=.27, p<001), ethical climate(β=.16, p=044), and the explanatory power of the variable was 24.2%. In order to increase the retention intention of general hospital nurses, it is necessary to increase job satisfaction and create a sound ethical climate, and to develop an intervention program that can increase the retention intention by age.

The Norwegian Forces' Gender Neutral Draft and Its Implication on the ROK Forces (노르웨이 성 중립 징병제와 한국군에 주는 시사점)

  • Cho, Sang Keun;Kim, In Chan;Hong, Myung Sook;Yu, Sun Young;Jeon, So Min;Park, Sang-Hyuk
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.2
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    • pp.197-202
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    • 2022
  • Gender neutral draft is the system that the level of manpower which military demands right now can be kept and the concept of gender equality can enlarge itself. This thesis draws implications on the necessity of optional review of draft and the amelioration of military organizational culture for the military through the example of Norway that has adopted gender neutral draft initially in Europe. The Military that is characterized by traditionally male led domain accelerates itself the openness to female by the aggrandizement of social participation and the improvement of human right for female. The various concerns about a necessary facilities, the period ofmilitary service, the level of salary, the keeping of combat power, etc just should be overcome in order to enlarge conscription to female in Korea. Situations such as the environment of national security, the level of social participation to female, the treatment to minority are different, so it is difficult for us to draw any conclusion whether the adoption of sex neutral conscription is right or not. Nonetheless, the national strategy that prepares for future may not be concluded easily and we can not stop it even though it is discomfortable truth. In Conclusion, we anticipate that the sound discourse on measures of including female in draft will be continued from the start with this thesis.