• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.19 no.6
• /
• pp.180-191
• /
• 2020

This study analyzes factors that affect average daily travel time budgets, using the Time Use Survey data from 1999 to 2014 in Seoul. We first developed multivariate regression models for travel time from each year, considering demographic and socio-economic variables as well as non-home activity time. The model results showed that household and personal characteristics and non-home activities significantly affect travel time, and their effects are different over time. In addition, we developed seemingly unrelated regression (SUR) models for time allocation for non-home activity and travel, considering their correlations, and explanatory variables were compared over time. Overall, demographic and socio-economic variables significantly affect travel time as well as non-home activity time.

• Journal of Information Technology Services
• /
• v.19 no.6
• /
• pp.177-189
• /
• 2020

The OECD has assessed Korea as the third highest in trade facilitation worldwide. The paperless trade of Korea is world class based on uTradeHub : national e-trade service's infrastructure for trade community. Over 800 trade-related document standards provide interoperability of message exchange and trade process automation among exporters, importers, banks, customs, airlines, shippers, forwarders and trade authorities. Most one-to-one unit processes are perfectly paperless & online; however, from the perspective of process flow, there is a lack of streamlining end-to-end trade processes spread over many different parties. This situation causes the trade community to endure repetitive-redundant load for handling trade documents. The trade community has a strong demand for seamless trade flow. For streamlining the trade process, processes with data should flow seamlessly to multilateral parties. Flowing data with an optimized process is the critical success factor to accomplish seamless trade. This study proposes four critical digital trade infrastructures as a platform service : (1) data-centric Intelligent Document Recognition(IDR), (2) data-driven Digital Document Flow (DDF), (3) platform based Digital Collaboration & Communication(DCC), and (4) new digital Trade Facilitation Index (dTFI) for precise assessment of K-Trade Digital Trade Framework. The results of new dTFI analyses showed that redundant reentry load was reduced significantly over the whole trade and logistics process. This study leads to the belief that if put into real-world application can provide huge economic gains by building a new global value chain of the K-trade eco network. A new digital trade framework will be invaluable in promoting national soft power for enhancing global competitiveness of the trade community. It could become the advanced reference model of next trade facilitation infrastructure for developing countries.

• Journal of the Economic Geographical Society of Korea
• /
• v.25 no.1
• /
• pp.171-181
• /
• 2022

The real estate price index plays key roles as quantitative data in real estate market analysis. International organizations including OECD publish the real estate price indexes by country, and the Korea Real Estate Board announces metropolitan-level and municipal-level indexes. However, when the index is set on the smaller spatial unit level than metropolitan and municipal-level, problems occur: missing values. As the spatial scope is narrowed down, there are cases where there are few or no transactions depending on the unit period, which lead index calculation difficult or even impossible. This study suggests a supervised learning-based machine learning model to compensate for missing values that may occur due to no transaction in a specific range and period. The models proposed in our research verify the accuracy of predicting the existing values and missing values.

• Journal of Internet Computing and Services
• /
• v.23 no.5
• /
• pp.33-46
• /
• 2022

This paper, in order to minimize the ground waiting time of an Air tanker, the queuing theory, that is, a queue that calculates the waiting time under single-server and multi-server situations, was used in the study. Since the national budget and resources are limited, the unlimited increase of the logistics support service team is limited. Therefore, the number of logistic support service teams that can adaptively control the ground waiting time according to the wartime preparation stage or war environment was calculated. The results of this study provide a stipulated standard for calculating the optimal number of air tanker logistic support service teams of the Air Force, providing a basis for the logistical commander to assign logistic support service teams to each stage from peacetime to wartime.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.12
• /
• pp.1908-1918
• /
• 2022

Recently, ASEAN is not only a new production base but also a consumer market for Korea, and interest in the utilization of production networks in each region is increasing. In particular, urbanization in ASEAN countries is progressing at a relatively fast pace. Each country is promoting smart city projects combined with ICT to improve outdated basic infrastructure facilities such as housing, transportation, logistics, crime prevention, and disaster prevention. The purpose of this study is to develop a web-based smart city export HUB platform so that companies with excellent domestic smart city solutions can participate in smart city construction through networks with ASEAN countries. These platforms can secure the demand for smart city construction in ASEAN countries, and through the establishment of the Korea-ASEAN public-private network, smart cities planned in ASEAN countries can be promoted more innovative. In addition, it is expected to be positioned as a Global smart city platform model by applying to real cities through collaboration with excellent domestic companies.

• Asia Marketing Journal
• /
• v.8 no.3
• /
• pp.1-11
• /
• 2006

The Bass model assumes two communication channels: mass-media and word-of-mouth. In this paper, we call the mass-media Type I channel of communications. The word-of-mouth channel means interaction between non-adopters and adopters. Let us call it Type II channel of communications. In the real world, however, the non-adopters who are not aware of the innovation can be affected by communications with other non-adopters who are aware of it. Let us call it Type III channel of communications to differentiate with Type II channel. This paper analyzes the impact of Type III channel on diffusion process. The result shows that exponential growth patterns (for example, the adoption patterns of the blockbuster movies) can be observed when non-adopters are influenced by other non-adopters who aware of the innovation.

• Atmosphere
• /
• v.34 no.1
• /
• pp.1-21
• /
• 2024

Private companies are increasingly required to take more substantial actions on climate change. This study introduces the principle and cases of climate (physical) risk estimation for 11 private companies in Korea. Climate risk is defined as the product of three major determinants: hazard, exposure, and vulnerability. Hazard is the intensity or frequency of weather phenomena that can cause disasters. Vulnerability can be reflected in the function that explains the relationship between past weather records and loss records. The final climate risk is calculated by multiplying the function by the exposure, which is defined as the area or value of the target area exposed to the climate. Future climate risk is estimated by applying future exposure to estimated future hazard using climate model scenarios or statistical trends based on weather data. The estimated climate risks are developed into three types according to the demand of private companies: i) climate risk for financial portfolio management, ii) climate risk for port logistics management, iii) climate risk for supply chain management. We hope that this study will contribute to the establishment of the climate risk management system in the Korean industrial sector as a whole.

• Journal of Advanced Navigation Technology
• /
• v.27 no.5
• /
• pp.534-539
• /
• 2023

Currently, in Korea, to obtain a jet type rating, you must receive training on a small business jet model. The reason is because of the law in the Aviation Safety Act Enforcement Rules 『Appendix 4』 that states, "You must receive at least 2 hours of flight training." In the end, it is acquiring type rating as a small business jet aircraft with relatively low operating costs. The qualifications acquired in this way are different from those for aircraft operated by airlines. However, if you have an initial jet type rating, you can acquire an airline aircraft qualification just by training on a simulator, so airlines want you to have at least a small-jet type rating. However, in the United States and Australia, there is a system in place to acquire initial jet type rating through simulator training without actual flight training.

• Journal of Digital Convergence
• /
• v.14 no.10
• /
• pp.277-285
• /
• 2016

The purpose of this study is to quantitatively and empirically investigate whether cartoon-realism, which is referred to as a guideline for avoiding the uncanny valley phenomenon, is actually effective. An experiment was carried out to investigate whether or not methods that try to realistically express the texture of human skin while making 3D models whose outward appearance abstract like a cartoon actually reduce the negative sentiments associated with the uncanny valley phenomenon. The results found that when human skin textures were applied to cartoon-type 3D models, the degree of eeriness significantly increased (p<0.05), while there was no change in the degree of human likeness. When cartoon-style skin textures were applied to human-type 3D models, there was no significant difference in the degree of eeriness, but the degree of human likeness significantly decreased (p<0.05). These results show that, cartoon realism is not actually effective, and rather creates a perceptual conflict and induces the uncanny valley phenomenon. The results of this study are expected to be used as quantitative and empirical data for developing design guidelines that will overcome the uncanny valley phenomenon in the future.

• The Journal of the Korea Contents Association
• /
• v.13 no.12
• /
• pp.829-839
• /
• 2013

This study is a descriptive research study with the purpose of predicting and comparing factors of depression affecting residents in a metropolitan city by using logistic regression analysis and decision-making tree analysis. The subjects for the study were 462 residents ($20{\leq}aged{\angle}65$) in a metropolitan city. This study collected data between October 7, 2011 and October 21, 2011 and analyzed them with frequency analysis, percentage, the mean and standard deviation, ${\chi}^2$-test, t-test, logistic regression analysis, roc curve, and a decision-making tree by using SPSS 18.0 program. The common predicting variables of depression in community residents were social dysfunction, perceived physical symptom, and family support. The specialty and sensitivity of logistic regression explained 93.8% and 42.5%. The receiver operating characteristic (roc) curve was used to determine an optimal model. The AUC (area under the curve) was .84. Roc curve was found to be statistically significant (p=<.001). The specialty and sensitivity of decision-making tree analysis were 98.3% and 20.8% respectively. As for the whole classification accuracy, the logistic regression explained 82.0% and the decision making tree analysis explained 80.5%. From the results of this study, it is believed that the sensitivity, the classification accuracy, and the logistics regression analysis as shown in a higher degree may be useful materials to establish a depression prediction model for the community residents.