• Journal of dental hygiene science
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• v.11 no.4
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• pp.345-352
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• 2011

The purpose of this study was to survey clinical dental hygienists for their perceived ethical dilemma and professionalism. The subjects in this study were 393 dental hygienists who randomly selected worked in dental clinics. After a survey was conducted, the collected data were analyzed with a SPSSWIN 18.0 program. The findings of the study were as follows: Dental hygienists perceived ethical dilemma scored 2.46 on a 5-point scale on average. In view of its sub-areas, the sub-areas which scored highest was 'dental hygienist with the profession'(2.62), followed by 'dental hygienist with object'(2.41) and 'dental hygienist with coworker'(2.34) in their order. Dental hygienists perceived professionalism scored 3.28 on a 5-point scale on average. In view of its sub-areas, the sub-areas which scored highest was 'sence of public service'(3.55), followed by 'autonomy'(3.42), 'reference professional group'(3.14) and 'sence of mission'(3.01) in their order. In regard to the relationship of the general characteristics to professionalism, those who were older, whose career was longer, whose education was highest and who were married were statistically significantly ahead of their counterparts in that aspect. In relation to factors affecting professionalism, longer career and higher education had a better impact on professionalism. Those factors made a 13% prediction of that.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.2
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• pp.406-413
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• 2022

The subsea pipeline pre-commissioning stage consists of the following processes: Flooding, Venting, Hydrotesting, Dewatering, Drying, and N2 Purging. Among these processes, drying and nitrogen purging processes are stipulated to reduce and maintain the relative humidity below dew point to prevent the generation of hydrate and the risk of gas explosion in the pipeline during operation. The purpose of this study is to develop an analysis method for the air drying and nitrogen purging process during pre-commissioning of the subsea pipeline, and to evaluate the applicability of the analysis method through comparison with on-site measurement results. An analysis method using Computational Fluid Dynamics (CFD) was introduced and applied as a method for evaluating the relative humidity inside a subsea pipeline, and it was confirmed that analysis results were in good agreement with the on-site measurement results for the air drying and nitrogen purging process of the offshore pipeline. If the developed air drying and nitrogen purging analysis method are used as pre-engineering tools for pre-commissioning of subsea pipelines in the future, it is expected to have a significant impact on the improvement of work productivity.

• Journal of Korean Society of Steel Construction
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• v.28 no.1
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• pp.13-22
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• 2016

Recently, interest for environmental pollution in various fields is on the increase, and the researches on the life cycle assessment of environmental performance assessment method for calculating the environmental loads are currently most performed. It is expected to have a significant influence on the environment, since SOC infrastructures are go through a variety of materials, manufacturing process, however it is judged that researches and measures for environmental pollution is insufficient. In this study, we build the data for 204 of steel bridge designed after 2000 year, and the 100 of bridge which were selected to from obtained results were calculated the environmental loads at the planning stage based on the life cycle assessment. In addition, standard classification systems in work type for steel bridges were established. Based on this, the basic design data and input materials for the bridges are applied to the LCI DB, and the environmental load for required material is evaluated and is shown as Eco-point. Environmental loads obtained from this study, it is judged that can be utilized as a basic data for the process of the life cycle assessment in future steel bridge design.

• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.343-347
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• 2010

Heavy application of fertilizer and manure in excess from the optimum requirement for crop growth can increase phosphorus (P) accumulation and P release potential in soils. In this study, the relationship between soil test P and 0.01M $CaCl_2$ extractable P was analysed to evaluate the P release potential of agricultural soils under different land-use. The paddy, upland, plastic film house(PFH) soils were sampled from Tongyoung and Changnyeong, and Daegok areas in Gyeongnam province, respectively. With respect to the P accumulation, available P contents in upland and PFH soils were 619 and 796 mg $P_2O_5$/kg, respectively indicating that different land-use types can greatly impact soil P accumulation. As soil available P was increased in the paddy soil, the content of 0.01M $CaCl_2$ extractable P also linearly increased without change point. Comparatively, P threshold were detected at 520 mg $P_2O_5$/kg in both upland and PFH soils, indicating that P release potential were higher in these land-use systems. For reducing P release from agricultural soils, management of optimum P content is needed in soils possessing high P release potential. Further, the change point value, if it is to be used as an environmental indicator, requires more detailed investigation to cover a wide range of soil characteristics.

• Korea journal of population studies
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• v.32 no.1
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• pp.139-164
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• 2009

The first demographic transition refers to the historical decline in mortality and fertility, as shown from the 18th Century in several European populations, and continuing present in most developing countries. The end point of the first demographic transition(FDT) was supposed to be a stationary and stable population corresponding with replacement fertility and zero population growth. In addition, households in all parts of the world would converge toward the nuclear and conjugal types, composed of married couples and their offspring. The second demographic transition(SDT), on the other hand, sees no such equilibrium as the end-point. Rather, new developments bring sub-replacement fertility, a multitude of living arrangements other than marriage, and the disconnection between marriage and procreation. Populations would face declining sizes if not complemented by new migrants. Over the last decades birth rates have been on the decline in all countries of the world, and it is estimated that already more than half of he world's population has below replacement level fertility. Measured in terms of the Total Fertility Rate (TFR), currently 34 countries have fertility levels of 1.5 or less. Similarly, Korea has been below lowest-low fertility for eight consecutive years since 2001 and below the replacement level for more than twenty years. In explaining the low fertility in Korea, some researchers explain the low fertility as revenge against a male-dominated society and institution, while others focus the impact of the employment instability. These studies share the basic ideas (spread of individualism, delayed marriage and childbearing, high divorce rate etc.) of a second demographic transition in order to explain the low fertility in Korea.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.3
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• pp.47-63
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• 2011

A traffic detection system can be deemed as a traffic data and information collection system to serve traffic policies, traffic management, and user services. The system plays a crucial role in verifying whether or not the current traffic system has issues or problems by checking out traffic data. In addition, the system does so in finding out a point or a section where an issue or a problem has occurred, if any, and in examining the causes of the issue or problem, the extent of its impact that has occurred and spread, and a method for resolving it. However, the existing point detection system of Korea has too many flaws. In order to fix the flaws, in this paper, the theoretical characteristics of the section detection system were researched in relation to the calculation of travel time. In addition, the travel time of probe cars was obtained by field survey, and it was compared to that of spot and section detection data. Then, simulation was performed to determine the optimal section detection interval. In conclusion, introduction of optimal section detection system was examined in order to achieve the advanced road management including traffic policy, traffic management, and user services.

• Journal of Korea Water Resources Association
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• v.53 no.11
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• pp.1025-1037
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• 2020

This study attempted to evaluate the spatial characteristics and applicability of the predicted ensemble rainfall data used for heavy rain alarms. Limited area ENsemble prediction System (LENS) has 13 rainfall ensemble members, so it is possible to use a probabilistic method in issuing heavy rain warnings. However, the accessibility of LENS data is very low, so studies on the applicability of rainfall prediction data are insufficient. In this study, the evaluation index was calculated by comparing one point value and the area average value with the observed value according to the heavy rain warning system used for each administrative district. In addition, the accuracy of each ensemble member according to the LENS issuance time was evaluated. LENS showed the uncertainty of over or under prediction by member. Area-based prediction showed higher predictability than point-based prediction. In addition, the LENS data that predicts the upcoming 72-hour rainfall showed good predictive performance for rainfall events that may have an impact on a water disaster. In the future, the predicted rainfall data from LENS are expected to be used as basic data to prepare for floods in administrative districts or watersheds.

• Korean Journal of Construction Engineering and Management
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• v.14 no.2
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• pp.131-140
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• 2013

Econometric forecast models based on past time-series data have been applied to a wide variety of applications due to their advantages in short-term point estimating. These models are particularly used in predicting the impact of governmental research and development (R&D) programs because program managers should assert their feasibility due to R&D program's huge amount of budget. The construction governmental R&D programs, however, separately make an investment by dividing total budget into five sub-business area. It make R&D program managers difficult to understand how R&D programs affect the whole system including economy because they are restricted with regard to many dependent and dynamic variables. In this regard, system dynamics (SD) model provides an analytic solution for complex, nonlinear, and dynamic systems such as the impacts of R&D programs by focusing on interactions among variables and understanding their structures. This research, therefore, developed SD model to capture the different impacts of five construction R&D sub-business by considering different characteristics of sub-business area. To overcome the SD's disadvantages in point estimating, this research also proposed the method for constructing quantitative forecasting model using qualitative data. Understanding the different characteristics of each construction R&D sub-business can support R&D program managers to demonstrate their feasibility of capital investment.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.23 no.2
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• pp.79-88
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• 2024

We used actual field data to analyze from a traffic engineering perspective how AI and edge computing technologies affect the reduction of traffic accidents. By providing object information from 20m behind with AI object recognition, the driver secures a response time of about 3.6 seconds, and with edge technology, information is displayed in 0.5 to 0.8 seconds, giving the driver time to respond to intersection situations. In addition, it was analyzed that stopping before entering the intersection is possible when speed is controlled at 11-12km at the 10m point of the intersection approach and 20km/h at the 20m point. As a result, it was shown that traffic accidents can be reduced when the high object recognition rate of AI technology, provision of real-time information by edge technology, and the appropriate speed management at intersection approaches are executed simultaneously.

• Korean Journal of Construction Engineering and Management
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• v.10 no.1
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• pp.156-166
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• 2009

Residential land development projects are tending upwards recently. However, an indiscreet residential land development has tended to damage environment by destroying existing green lands and trees of target lands and generating many cut slopes with transformation of its topography. There are Prior Environmental Review(PER) for district designation and Environmental Impact Assessment(EIA) before approval on development plans. PER is implemented after developing a residential land development plan and EIA is implemented after completing a detail design. As the result, many of residential land development projects are passive to reduce potential environmental problems on the designated sites. Object of this study is to construct an evaluation system on alternatives in the early step of site designation for implementing residential land development projects with environment-friendly and sustainable way. For this, alternative evaluation model is constructed by using Fuzzy Inference and Analytic Hierarchy Process(AHP) method based on Environmental Evaluation Factors of residential land development project, which are proposed in the precedent research. If a decision maker evaluates environment damage by ten-point method, the point is transformed Environmental Performance(EP) by Fuzzy Inference, and then, applying weight that is already calculated by AHP method, Total Environmental Performance(TEP) is calculated. After all, an alternative with the highest TEP is selected as the best one. Using this evaluation system, more than two alternatives of residential land development project site, which can hold location appropriateness in the early under undecided land use plan, can be evaluated quantitatively. As environmental damages, which can be generated by implementing a residential land development project, can be detected in the early step, environmental damages can be removed or reduced at the source.