• Journal of Navigation and Port Research
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• v.45 no.1
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• pp.9-15
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• 2021

According to IMO, MASS is defined as a vessel operated at various levels independent of human interference. The safety navigation support service for MASS is designed to improve the safety and efficiency of MASS by developing public services on shore for ship arrivals/departures and for cargo handling. The safety navigation support service consists of a total of six types of services: autonomous operation, berthing/unberthing/mooring, cargo handling and ship arrival/departure service, PSC inspection, condition monitoring, and accident response support services. In order to support accident response service, the relative importance of a bridge navigational equipment was assessed by stratifying the navigation system to provide safe and efficient support services by objective judgment through specific and quantitative methods using AHP, one of decision-making methods used by an expert group. The survey was conducted by dividing the bridge navigational equipment into depth, location, and speed information. As a result of applying the AHP method, the importance of depth, location, and speed information was assessed. The relative importance of each equipment for providing location information was also assessed in order of Radar, DGPS, ECDIS, Gyro compass, Autopilot, and AIS. This was similar to survey results on the utilization of each operator's preference and its impact on marine accidents.

• Applied Chemistry for Engineering
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• v.31 no.6
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• pp.674-678
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• 2020

In this study, a Pd/TiO2 catalyst which oxidized H2 at room temperature without an additional energy source was prepared. And a specific surface area of TiO2 as a support was not proportional to H2 oxidation reaction performance of Pd/TiO2 catalyst. In addition La2O3 was added to Pd/TiO2 catalyst in order to evaluate the performance effect due to the change of catalysts physical properties. A Pd/La2O3-TiO2 was prepared by adding different amounts of La2O3 to TiO2 and CO chemisorption analysis was performed. Compared to the conversion rate (14% at 0.5% H2) of the Pd/TiO2(G) catalyst, the Pd/La2O3-TiO2 catalyst showed 74% which was improved by more than five times. It was found that the larger the metal dispersion of Pd as an active metal is, the more favorable to H2 oxidation reaction is. However, when the added La2O3 amount exceeded 10%, the catalyst performance decreased again. Finally, it was concluded that the physical properties of the Pd/La2O3-TiO2 catalyst have a dominant influence on the catalytic activity until 0.3~0.5% of injected H2 concentrations and the catalyst reaction rate was controlled by substance transfer from 1% or more concentrations of H2.

• Smart Media Journal
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• v.9 no.4
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• pp.176-186
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• 2020

The size and shape of crops are diverse, and the growing environment is also different. Therefore, when one uses a drone to spray pesticides, the characteristics of each crop must be considered, and flight conditions such as the flight height and forwarding velocity of the drone should be changed. The droplet flow of pesticides is affected by various flight conditions, and a large change occurs in the sprayed area. As a result, an uneven distribution of liquid may be formed at the wake, and the transport efficiency will be decreased as well as there would be a risk of toxic scatter. Therefore, this paper analyzes the degree of distribution of pesticides to the crops through numerical analysis when pesticide is sprayed onto the selected three crops with different characteristics by using agricultural drones with different flight conditions. On the purpose of establishing a guideline for spraying pesticides using a drone in accordance with the characteristics of crops, this paper compares the amount of pesticides distributed in the crops at the wake of nozzle flow using the figure of merit, and the sum of transported liquid rate divided by the root mean square of the probability density function.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.87-96
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• 2020

To use a hydraulic structure effectively, the velocity of a river should be known in detail. In reality, velocity measurements are not conducted sufficiently because of their high cost. The formulae to yield the flux and velocity of the river are commonly called the Manning and Chezy formulae, which are empirical equations applied to uniform flow. This study is based on Chiu (1987)'s paper using entropy theory to solve the limits of the existing velocity formula and distribution and suggests the velocity and distance formula derived from information entropy. The data of a channel having records of a spot's velocity was used to verify the derived formula's utility and showed R2 values of distance and velocity of 0.9993 and 0.8051~0.9483, respectively. The travel distance and velocity of a moving spot following the streamflow were calculated using some flow information, which solves the difficulty in frequent flood measurements when it is needed. This can be used to make a longitudinal section of a river composed of a horizontal distance and elevation. Moreover, GIS makes it possible to obtain accurate information, such as the characteristics of a river. The connection with flow information and GIS model can be used as alarming and expecting flood systems.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.153-160
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• 2021

Nitrous oxide is a global warming substance and is known as the main cause of the destruction of the ozone layer because its global warming effect is 310 times stronger than carbon dioxide, and it takes 120 years to decompose. Therefore, in this study, we investigated the characteristics of NOx emission from N2O reduction by thermal decomposition of N2O. Bunsen premixed flames were adopted as a heat source to form a high-temperature flow field, and the experimental variables were nozzle exit velocity, co-axial velocity, and N2O dilution rate. NO production rates increased with increasing N2O dilution rates, regardless of nozzle exit velocities and co-axial flow rates. For N2O, large quantities were emitted from a stable premixed flame with suppressed combustion instability (Kelvin Helmholtz instability) because the thermal decomposition time is not sufficient with the relatively short residence time of N2O near the flame surface. Thus, to improve the reduction efficiency of N2O, it is considered effective to increase the residence time of N2O by selecting the nozzle exit velocities, where K-H instability is generated and formed a flow structure of toroidal vortex near the flame surface.

• Journal of Industrial Convergence
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• v.19 no.4
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• pp.111-126
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• 2021

The purpose of this study was to investigate the effects of 12-week training on changes in physical fitness and cardiovascular factors for firefighters. For this purpose, 40 men in their 20s and 30s who agreed to participate voluntarily were recruited. They were divided into four groups: the firefighters' physical fitness test training group (hereinafter referred to as PT group), firefighters' physical fitness test and aerobic training group (hereinafter referred to as PT+AR group), firefighters' physical fitness test and both aerobic and anaerobic training group (hereinafter referred to as PT+CO group). Physical fitness factors (grip strength, back muscle strength, seated forward bend, standing long jump, sit-ups, 20-meter shuttle run), cardiovascular factors (total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, glucose, waist circumference, systolic blood pressure, diastolic blood pressure) and the relationship between Framingham Heart Risk Score and physical/cardiovascular factors were compared and analyzed, and the following conclusions were obtained. Aerobic training, anaerobic training, and combined training, including 12 weeks of firefighter physical examinations, all had positive effects on fitness and cardiovascular factors, which would be an appropriate way for firefighter examinees to improve physical strength and reduce the risk of cardiovascular disease.

• Journal of the Korea Society of Computer and Information
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• v.26 no.8
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• pp.127-137
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• 2021

This research studies the perception types of 119 rescue workers among emergency rescue department students, and was carried out to identify the types of perception of 119 rescue workers among firefighters and to prepare basic data to find out the characteristics of each type. As a result of analysis on the Q sample consisting of 27 statements by executing the Q UANL program on a total of 54 students from the Emergency rescue department, it is confirmed that there were 3 types, which accounted for 45% of the total variable. When looking at the explanatory power per type, it turned out: 32% for Type I; 6.7% for Type II; and 5.8% for Type III. Each type was named as follows: our Superman for Type I ; suffering hero for Type II ; and rescue expert for Type III. Overall, there were 119 rescue workers as follows : rescue workers in lexical meaning; and 119 rescue workers who were in difficult situations suffering from post-traumatic stress disorder and needed to be covered and protected by citizens. In addition, there was a perception of 119 rescue workers who were recognized as a specialist and carry out his/her lifesaving duties without a single mistake. Therefore, in order for 119 rescue workers to be recognized as a specialized field of rescue, a program in which 119 rescue workers can share various training and experiences must be provided and researched.

• The Journal of the Convergence on Culture Technology
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• v.7 no.3
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• pp.59-69
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• 2021

The Moon Jae-in administration insisted on reforming the prosecution for the reform of power institutions, and also tried to control the power of the prosecution through the establishment of a high-ranking public officials criminal investigation office. Then, what is the direction of the legal prosecution reform? Above all, it is a logic to drastically reduce the power of the prosecution. How to shrink it? First, it is necessary to control or check the power of prosecution and investigation that the prosecution has. Second, the key to the reform of the prosecution is perhaps to separate personnel rights from power. In order to exclude external pressure from the prosecution's personnel rights, there must be no instruction or intervention from the attorney general. To do this, the prosecutor general must go through various personnel evaluations, such as multi-faceted evaluation. Third, the essence of the High-ranking Officials Criminal Investigations Act is to deal with crimes of prosecutors, judges, police, and members of the National Assembly. It is also the core of the institutional mechanism to cover the corruption of one's family members while holding all the right to investigate, prosecution, and warrant claims, and to check the omnipresent prosecutors who have abused their right to investigate for political purposes. Then, what is necessary for the success of the high-ranking officials criminal investigation office? Above all, We think political neutrality is very necessary. The Ministry of Airborne has a very high authority of the Director. This paper intends to examine the functions and roles of the prosecution and high-ranking officials criminal investigation offices to prevent corruption. We analyzed the contents of the prosecution and the public officials criminal investigation office, and examined the limitations and problems, and the measures to control corruption in public offices.

• Journal of Korea Water Resources Association
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• v.54 no.8
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• pp.567-576
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• 2021

Climate change threatens the security of domestic water resources in South Korea. To overcome the potential water shortage, various approaches are being studied by alterning the operation of dams or by integrated operation of multiple dams and reservoirs. However, most of the related researches were developed and applied for multi-purpose dams, and few studies were conducted for the hydropower dams. The main purpose of the hydropower dam is to generate electric energy; however, the potential water shortage due to prolonged droughts brings the idea to supply water from the hydropower dam in the basin. To that end, it is required to estimate the water supply ability of the hydropower dams. In this study, we proposed a methodology to classify the hydropower dam into a "storage-type" and "run-of-river type" dam. The proposed approach was demonstrated using the hydropower dams located in North-han River basin. The results of this study are expected to contribute for further analysis of the hydropower dams, such as evaluation of water supply capacity and drought mitigation purpose operation of the hydropower dams.

• The Journal of the Korea Contents Association
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• v.21 no.5
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• pp.221-233
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• 2021

This study analyzed the contents of changes in educational policy from the perspective of policy learning, based on the awareness of the lack of academic efforts to identify such phenomena despite repeated policy failures in educational policy. To this end, it has been more than 20 years since the policy was established, but it was analyzed using the policy analysis case of the teacher incentive policy, which still had severe conflicts between the government and teacher unions. As a result of the analysis, first, there were 11 changes in the policy content from the Kim Dae-jung administration to the Moon Jae-in administration. Whenever the government was newly launched, not only the contents of the policy for teacher incentives changed, but also the policy changes continued during the same government period. Second, when analyzing what kind of policy learning took place at the stage of change in each government's policy content, most of them were 'political policy learning' or 'instrumental policy learning'. Rather than a fundamental discussion about the goal of the policy, it has only repeated policy learning that adjusts only the ratio of differential payments to defend the teacher incentive policy. In order to recover from this current situation, this study suggests that it is necessary to present an alternative policy that can change the rigid society of teachers through 'social policy learning', which examines the basic values and strategies of teacher incentive policies.