• International Journal of Highway Engineering
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• v.18 no.3
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• pp.47-57
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• 2016

PURPOSES : This study aims to examine the differences between the existing traffic demand forecasting method and the traffic demand forecasting method considering future regional development plans and new road construction and expansion plans using a four-step traffic demand forecast for a more objective and sophisticated national highway maintenance. This study ultimately aims to present future pavement deterioration and budget forecasting planning based on the examination. METHODS : This study used the latest data offered by the Korea Transport Data Base (KTDB) as the basic data for demand forecast. The analysis scope was set using the Daejeon Metropolitan City's O/D and network data. This study used a traffic demand program called TransCad, and performed a traffic assignment by vehicle type through the application of a user equilibrium-based multi-class assignment technique. This study forecasted future traffic demand by verifying whether or not a realistic traffic pattern was expressed similarly by undertaking a calibration process. This study performed a life cycle cost analysis based on traffic using the forecasted future demand or existing past pattern, or by assuming the constant traffic demand. The maintenance criteria were decided according to equivalent single axle loads (ESAL). The maintenance period in the concerned section was calculated in this study. This study also computed the maintenance costs using a construction method by applying the maintenance criteria considering the ESAL. The road user costs were calculated by using the user cost calculation logic applied to the Korean Pavement Management System, which is the existing study outcome. RESULTS : This study ascertained that the increase and decrease of traffic occurred in the concerned section according to the future development plans. Furthermore, there were differences from demand forecasting that did not consider the development plans. Realistic and accurate demand forecasting supported an optimized decision making that efficiently assigns maintenance costs, and can be used as very important basic information for maintenance decision making. CONCLUSIONS : Therefore, decision making for a more efficient and sophisticated road management than the method assuming future traffic can be expected to be the same as the existing pattern or steady traffic demand. The reflection of a reliable forecasting of the future traffic demand to life cycle cost analysis (LCCA) can be a very vital factor because many studies are generally performed without considering the future traffic demand or with an analysis through setting a scenario upon LCCA within a pavement management system.

• Journal of Chest Surgery
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• v.13 no.2
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• pp.85-91
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• 1980

Extracorporeal circulation by hemodilution technique has been currently used with its clinical safety and good peripheral tissue perfusion in open heart surgery. There is no doubt that $O_{2}$ carrying capacity of the blood is disturbed by decreased hemoglobin level resulting from hemodilution of the circulating blood. From the view point of the blood gas exchange, these experimental studies were undertaken to determined the sate limit of hemodilution in the condition of cardiopulmonary bypass with a constant perfusion flow rate. Twelve adult mongrel dogs weighing 10 to 13 Kg. were anesthetized with pentobarbital and then respiration was controlled with Harvard volume respirator using room air. The cardiopulmonary by pass was performed by use of Sarns heart lung machine (console 5000, 5 head and 2 roller pumps) and Travenol pediatric bubble oxygenator. The perfusion rate during bypass was maintained at a constant rate of 80 ml/min/Kg of body weight. The ratio of oxygen gas flow to blood flow was kept in 3 to 1 constantly. International hemodilution was attained by serial blood withdrawals and immediate infusion of equal volumes of diluants composed of Ringer's lactate, 5% dextrose in water and 25% mannitol solution, proportionally 60%, 30%, and 10%. Arterial and venous blood samples were obtained between 15 and 20 minutes following each hemodilution. Hematocrits and hemoglobin values, $PO_{2}$, $PCO_{2}$ and pH were measured. Oxygen and carbon dioxide contents oxygen consumption and carbon dioxide elimination were calculated groups according to different hematocrit values and the correlations were evaluated. Result were as follows. 1. the arterial $O_{2}$ tension and $O_{2}$ saturation were maintained at the physiological level irrespective of the hematocrit value. 2. The venous $O_{2}$ tension and $O_{2}$ saturation showed a tendency to decline with the decrease in hematocrit value and positive correlation between them (r = +0.49, r = +0.76), The mean values of venous $O_{2}$ tension and $O_{2}$ saturation, however, were not decreased when the hematocrit levels were lower than 20%. 3. The arterial $O_{2}$ content declined lineally in proportion to the fall of hematocrit level with a positive correlation between them (r = +0.95). 4. The venous $O_{2}$ contents were decreased gradually as the hematocrit value decreased with positive correlation between them ( r =+0.89). The trend of diminution of venous $O_{2}$ content, however, was became low according to progressive decrease of hematocrit level. 5. Systemic oxygen consumption was in higher range than $O_{2}$ requirement of basal metabolism when the hematocrit value was above 20%, but abruptly decreased when the hematocrit value became to below 20%. 6. The arterial $CO_{2}$ tension and $CO_{2}$ content showed trend of increasing with progressive decrease of hematocrit value but exhibited a rather broad range and there was no relationship between those value and the hematocrit value. 7. The venous $CO_{2}$ tension and $CO_{2}$ content have also no correlation with change of Ht. value but related directly to those value of arterial blood with positive correlation between them (r = +0.78, r = +0.95_. 8. A-V difference of $CO_{2}$ content and $CO_{2}$ elimination wasnot significantly influenced by Ht. value. From the results, we obtained that feasible limit in inteneional hemodilution is above the hematocrit value of 20% under the given experimental condition.

• Journal of Korea Technology Innovation Society
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• v.12 no.3
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• pp.471-498
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• 2009

The ability to judge a country's scientific standing is vital for the governments and businesses that must decide scientific priorities and funding. In this paper, we analyze the output and outcomes from research investment over the recent years, to measure the quality of scientific research on national scales and to set it in an international context. There are many ways to evaluate the quality of scientific research, but few have proved satisfactory. To measure the quantity and quality of science in different nations, we analyzed the numbers of published research papers and their citations. The number of citations per paper is a useful measure of the impact of a nation's research output. Essential at a were acquired from SCI database by Thomson Scientific, which indexes more than 8,000 journals, representing most significant materials in science and engineering. The purpose of this paper is to evaluate and compare the output and outcomes among nations in a variety of viewpoints and criteria. One of the implications in response to the result of analysis is that sustainable economic development in highly competitive world markets requires a direct engagement in the generation of knowledge. Even modest improvement in healthcare, clean water, sanitation, food, and transport need capabilities in engineering, technology, and medicine beyond many countries' reach. Nations exporting natural resources such as gold and oil can import technology and expertise, but only until these resources are exhausted. For them, sustainability should imply investment in alternative agricultural and technological capabilities through improvements in their skills base. A strong science base does not necessarily leat to wealth generation. However, strength in science has additional benefits for individual nations, and for the world as a whole.

• Journal of Distribution Science
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• v.12 no.2
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• pp.59-71
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• 2014

Purpose - In recent years, many firms have attempted various approaches to cope with the continual increase of aviation transportation. The previous research into freight charge forecasting models has focused on regression analyses using a few influence factors to calculate the future price. However, these approaches have limitations that make them difficult to apply into practice: They cannot respond promptly to small price changes and their predictive power is relatively low. Therefore, the current study proposes a freight charge-forecasting model using time series data instead a regression approach. The main purposes of this study can thus be summarized as follows. First, a proper model for freight charge using the autoregressive integrated moving average (ARIMA) model, which is mainly used for time series forecast, is presented. Second, a modified ARIMA model for freight charge prediction and the standard process of determining freight charge based on the model is presented. Third, a straightforward freight charge prediction model for practitioners to apply and utilize is presented. Research design, data, and methodology - To develop a new freight charge model, this study proposes the ARIMAC(p,q) model, which applies time difference constantly to address the correlation coefficient (autocorrelation function and partial autocorrelation function) problem as it appears in the ARIMA(p,q) model and materialize an error-adjusted ARIMAC(p,q). Cargo Account Settlement Systems (CASS) data from the International Air Transport Association (IATA) are used to predict the air freight charge. In the modeling, freight charge data for 72 months (from January 2006 to December 2011) are used for the training set, and a prediction interval of 23 months (from January 2012 to November 2013) is used for the validation set. The freight charge from November 2012 to November 2013 is predicted for three routes - Los Angeles, Miami, and Vienna - and the accuracy of the prediction interval is analyzed using mean absolute percentage error (MAPE). Results - The result of the proposed model shows better accuracy of prediction because the MAPE of the error-adjusted ARIMAC model is 10% and the MAPE of ARIMAC is 11.2% for the L.A. route. For the Miami route, the proposed model also shows slightly better accuracy in that the MAPE of the error-adjusted ARIMAC model is 3.5%, while that of ARIMAC is 3.7%. However, for the Vienna route, the accuracy of ARIMAC is better because the MAPE of ARIMAC is 14.5% and the MAPE of the error-adjusted ARIMAC model is 15.7%. Conclusions - The accuracy of the error-adjusted ARIMAC model appears better when a route's freight charge variance is large, and the accuracy of ARIMA is better when the freight charge variance is small or has a trend of ascent or descent. From the results, it can be concluded that the ARIMAC model, which uses moving averages, has less predictive power for small price changes, while the error-adjusted ARIMAC model, which uses error correction, has the advantage of being able to respond to price changes quickly.

• International Journal of Highway Engineering
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• v.20 no.2
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• pp.45-55
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• 2018

PURPOSES : This study aims to survey and analyze the status of the design and completion documents output delivery system in public construction projects in order to assess the problems of the Ministry of Land, Infrastructure and Transport (MOLIT)'s electronic delivery system, with a focus on roads and rivers, and to offer improvement measures. METHODS : This study first surveys and analyzes laws and existing study trends with regard to the design and completion documents output delivery system in public construction projects. It further analyzes the status of the output delivery system in public construction projects, including roads, rivers, expressways, water resources, and railroads. In addition, a comparative analysis of the current electronic delivery system of MOLIT and Korea Expressway Corporation in the road field is conducted, and the problems and improvement measures for MOLIT's electronic output delivery system are presented. This study seeks to analyze problems and prepare improvement measures with regard to road and river public construction projects, as ordered by MOLIT's five regional offices. RESULTS : This study sought to prepare the electronic output delivery system with regard to public construction projects and present the analysis of its major problems and improvement measures in four categories: "the preparation of electronic design documents output delivery system improvement measures including inspection and delivery," "preparation of guidelines, systems, etc., concerning electronic design documents," "preparation of improvement measures for the construction project management system and electronic design document support tools", and "linking of MOLIT's electronic output delivery system with relevant agencies and the expansion thereof to local governments." CONCLUSIONS : This study analyzed the current status and problems of the MOLIT's electronic output delivery system in the field of road and river construction projects, and presented corresponding improvement measures. This study is expected to address the problems of the MOLIT's electronic output delivery system, and to provide the foundation for the preparation of an efficient electronic output delivery system for design and completion documents. In addition, this study is expected to boost the quality and utilization of the electronic design documents output, and to exchange, share, and link construction information among relevant agencies so as to prepare the foundation for sharing construction information.

• Journal of Environmental Science International
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• v.18 no.9
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• pp.971-981
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• 2009

An objective of this study is as follows: 1) performing sensitivity analysis and parameter estimation of RMA2 and RMA4 models for the West-Nakdong River, 2) drawing up alternatives of gates-operation for water-quality enhancement, and 3) quantitative evaluation of methodology of 'flow-restoration by gates-operation' among 'Comprehensive Plan Improving Water-Quality in the West-Nakdong River(WNR)' with the target water-quality(BOD at Nakbon-N point: below 4.3 mg/L). The parameters for the RMA2 (depth-averaged two-dimensional flow model) and RMA4 (depth-averaged two-dimensional water-quality model) were determined by sensitivity analysis. Result of parameter estimation for RMA2 and RMA4 models is $1,000\;Pa{\cdot}s$ of the eddy viscosity, 20 of the Peclet number, 0.025 of the Manning coefficient, and $1.0\;m^2/s$ of the diffusion coefficient. We have evaluated the effects of water-quality enhancement of the selected alternatives by numerical simulation technique with the models under the steady-state flow condition and the time-variant transport condition. Because of no-resuspension from river bottom and considering BOD as conservative matter, these simulation results slightly differ from real phenomena. In the case of $50\;m^3/s$ of Daejeo-gate inflow, two-dimensional flow pn results result represents that small velocity occurs in the Pyungkang Stream and no flow in the Maekdo River. In the WNR, there occurs the most rapid flow near timhae-bridge. In the WNR, changes of water-quality for the four selected simulation cases(6, 10, 30, $50\;m^3/s$ of the Daejeo-gate inflow) were predicted. Since the Daejeo-Gate and the Noksan-Gate can be opened up to 7 days, it would be found that sustainable inflow of $30\;m^3/s$ at the Daejeo-gate makes BOD in the WNR to be under the target of water-quality.

• The Korean Journal of Air & Space Law and Policy
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• v.8
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• pp.71-84
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• 1996

최근 남북관계는 대북 쌀 지원 문제와 관련한 북한 측의 태도와 이후의 무장공비 남파 등으로 악화되어 있다. 북한 측을 대화창구로 유도하고 남북 경협 등을 통하여 남북한 관계를 개선하려는 우리측의 노력은 이무런 성과를 거두고 있지 못한 것 같다. 남북한 항공판계의 진전도 전반적인 남북관계에서만이 고려가 가능한 실정으로 있다. 최근 언론매체를 통하여 북한당국이 미국 항공사(델타, 노스웨스트)의 평양비행정보구역 통과 우리 영공으로의 비행을 허가하였으며, 이에 대하여 우리측은 우선 남북한 관제당국간 관제협정이 체결되고, 동 항로를 이용한 비행은 우리 항공사를 포함한 모든 항공사에 비차별적으로 적용되어야 하는 것을 전제로 운항을 허가할 수 있음을 밝혔다. 이것은 북한당국이 '95년 12월에 자국영공을 전세계에 개방하겠다고 밝힌 후 진전된 일련의 사태 발전의 일부분이다. 북한은 '95.2월 초 국제영공통과 업무협정에 가입하였다. 외국항공기에 의한 북한의 영공통과비행은 이 협정에 가입하였다고 자동적으로 허가되는 것은 아니며 사안별로 허가되어야 한다는 점에 유의할 필요가 있다. 북한이 이러한 영공개방의사를 밝힌 것은 오랫동안 진행되어 왔던 일본/중국간 직선항로 문제에 있어서, 한국과 중국간의 합의로 서울/북경간에 직선항로를 설정하게 됨으로써 사실상 문제가 해결되었고, 따라서 향후 외국항공사가 한반도의 남쪽만을 통과하여 동경/북경간을 운항하게되는 가능성에 대하여 당혹감을 가지고 있기 때문이라고 보여진다. 한편 일본/중국간 직선항로 설정문제는 이것이 운항시간과 연료를 절약하게 된다는 점에서 IATA, ICAO 등 국제기구에 의하여 1980년대 초반부터 추구되어져 왔다. 그러나 남북간의 대립 등 복잡한 한반도 정세, 남북한을 포함한 일본, 중국 등 이해관계 당사국의 ICAO에 대한 형식적이고 외교적인 태도 등으로 인하여 아무런 해결책없이 십수년이 지나가게 되었다. 심지어 ICAO는 '88년 휴전선을 통과하는 단일항로안까지 제시하였는 바 이것은 한반도 정세에 대한 뚜렷한 이해가 없었던 때문이라고 생각된다. '95.9.17. "남복간 화해, 불가침, 교류 및 협력에 관한 합의서"가 서명되었다. 동 합의서에서는 남북간 군사적 대치 상태가 해소되는 상황에 따라 김포 및 순안비행장간 직항로를 개설한다고 되어있다. 현재까지 항공부문에서는 이렇다할 교류, 협력 실적은 없었으나 향후 남북관계의 진전에 따라 이 부문에서의 협력사업은 많다고 생각된다. 우선 위에서 언급한 남북한 및 각국 항공기가 남북의 비행정보구역을 통과 비행할 수 있도록 관제협정을 체결하고 필요할 경우 기술인력을 훈련하는데 상호 협조할 수 있다. 또한 설악산과 금강산을 연결하는 관광코스를 개발하여 항공기를 운항할 수 있다. 다음 남북의 주요 지점간에 전세기를 운항하고, 수요가 성숙할 경우 주요 도시 (남: 서울, 부산, 대구, 광주, 제주 등, 북: 평양, 신의주, 청진, 원산 등)를 연결하는 정기편을 개설할 수 있을 것이다. 이밖에 항공사간 영업사항에 관한 협력을 기대해 볼 수 있다. 남북간 항공협력은 한반도의 통일을 앞당길 수 있는 좋은 수단으로 작용할 수 있다.

• Journal of Environmental Science International
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• v.20 no.6
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• pp.783-788
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• 2011

Different from the main land of South Korea, Jeju Island has been in difficulties for measuring discharge. Due to high infiltration rate, most of streams in Jeju Island are usually in the dried state except six streams with the steady base flow, and the unique geological characteristics such as steep slope and short traveling distance of runoff have forced rainfall runoff usually to occur during very short period of time like one or two days. While discharge observations in Jeju Island have been conducted only for 16 sites with fixed electromagnetic surface velocimetry, effective analysis and validation of observed discharge data and operation of the monitoring sites still have been limited due to very few professions to maintain such jobs. This research is sponsored by Ministry of Land, Transport and Maritime Affairs to build water cycle monitoring and management system of Jeju Island. Specifically, the research focuses on optimizing discharge measurement techniques adjusted for Jeju Island, expanding the monitoring sites, and validating the existing discharge data. First of all, we attempted to conduct discharge measurements in streams with steady base flow, by utilizing various recent discharge monitoring techniques, such as ADCP, LSPIV, Magnetic Velocimetry, and Electromagnetic Wave Surface Velocimetry. ADCP has been known to be the most accurate in terms of discharge measurement compared with other techniques, thus that the discharge measurement taken by ADCP could be used as a benchmark data for validation of others. However, there are still concerns of using ADCP in flood seasons; thereby LSPIV would be able to be applied for replacing ADCP in such flooded situation in the stream. In addition, sort of practical approaches such as Magnetic Velocimetry, and Electromagnetic Wave Surface Velocimetry would also be validated, which usually measure velocity in the designated parts of stream and assume the measured velocity to be representative for whole cross-section or profile at any specified location. The result of the comparison and analysis will be used for correcting existing discharge measurement by Electromagnetic Wave Surface Velocimetry and finding the most optimized discharge techniques in the future.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.3
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• pp.39-63
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• 2020

This paper reviews the Interpretative Guidelines on EU passenger rights regulations in the context of the developing situation with COVID-19 of EU commission. To enlighten the obscurity and to mitigate the economic impacts of the COVID-19, European Commission has published "Interpretative Guidelines on EU passenger rights regulations in the context of the developing situation with Covid-19" on March 18, 2020. The Guideline essentially aims to create a coherent system of rules to assist the passengers, industry and national authorities overall under the unprecedented circumstances across the European Union. To do so, the Guideline is drafted to cover the rights of passengers travelling by air, rail, ship or bus/coach, maritime and inland waterways, as well as the corresponding obligations for carriers. From an aviation industry focused perspective, by referencing the Regulation (EC) numbered 261/2004, the Guideline specifically applies to cancellation and delay in flights which are seen as the dark spots for the air carriers concerning potential burdens.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.6
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• pp.694-700
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• 2018

Korea has disposed of medium and low level radioactive waste generated by operating nuclear power plants permanently through the radioactive waste repository located in Gyeongju. However, the maritime transport of radioactive waste is exposed to the risk of marine accidents, and it will be necessary to introduce a system to secure safety from the viewpoint of the function and role of the Korea Coast Guard. Especially, Korea is affected by large-scale marine accidents, such as the Hebei Spirit or Sewol accidents. From this point of view, we analyzed the current status of Korea radioactive waste shipping and examined the response systems of major foreign countries. As a result of examining major cases of accidents, we have operated an Emergency Towing Vessel (ETV) fleet centering on European countries in order to respond urgently to marine casualties that may have social, regional and international effects, such as accidents of similar nuclear material carriers and dangerous cargo ships. It proves a partial effect. Based on this, we propose the introduction of the Korean ETV System. In other words, it is necessary to respond to large-scale marine accidents that could lead to enormous environmental, property, and personal damage, such as marine accidents involving nuclear material ships, large oil tankers, and large passenger ships. For this, it seems necessary to introduce Korea ETV, which can carry out emergency towing, oil pollution control function, large - scale rescue equipment and manpower. This will lead to the enhancement of the Korea Coast Guard response to marine accidents, and will not miss the golden time of the initial response to the national disaster, which will help protect precious people, property and the environment.