• Korean Journal of Remote Sensing
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• v.40 no.4
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• pp.351-361
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• 2024

Satellite imagery contains various elements such as clouds, cloud shadows, and terrain shadows. Accurately identifying and eliminating these factors that complicate satellite image analysis is essential for maintaining the reliability of remote sensing imagery. For this reason, satellites such as Landsat-8, Sentinel-2, and Compact Advanced Satellite 500-1 (CAS500-1) provide Usable Data Masks(UDMs)with images as part of their Analysis Ready Data (ARD) product. Precise detection of clouds and their shadows is crucial for the accurate construction of these UDMs. Existing cloud and their shadow detection methods are categorized into threshold-based methods and Artificial Intelligence (AI)-based methods. Recently, AI-based methods, particularly deep learning networks, have been preferred due to their advantage in handling large datasets. This study aims to analyze the applicability of constructing UDMs for high-resolution satellite images through deep learning-based cloud and their shadow detection using open-source datasets. To validate the performance of the deep learning network, we compared the detection results generated by the network with pre-existing UDMs from Landsat-8, Sentinel-2, and CAS500-1 satellite images. The results demonstrated that high accuracy in the detection outcomes produced by the deep learning network. Additionally, we applied the network to detect cloud and their shadow in KOMPSAT-3/3A images, which do not provide UDMs. The experiment confirmed that the deep learning network effectively detected cloud and their shadow in high-resolution satellite images. Through this, we could demonstrate the applicability that UDM data for high-resolution satellite imagery can be constructed using the deep learning network.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.4
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• pp.519-529
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• 2024

Vehicle toll discounts on private roads are categorized into two types: non-sunset and sunset. Sunset types refer to provisions in which all or part of a law loses its effect upon a specific legislator-set deadline. Vehicles eligible for 'sunset' discounts include cargo vehicles operating late at night and eco-friendly vehicles powered by electricity or hydrogen. Korean government has subsidized all reduced toll fees for vehicles classified as non-sunset types on private roads to operators, but no subsidies have been provided for toll reductions on sunset vehicles. The rapid increase in electric hydrogen vehicles escalates the burden of reduced toll revenue on private road operators. This study analyzed traffic volume and toll reduction data from eight private road operators nationwide as of the end of 2023 to propose the necessity and method of supporting sunset-type toll reduction subsidies. In 2022, the subsidy for non-sunset types amounted to 87.5 billion won, or 18.6 % of total traffic revenue. The toll exemption and reduction ratio under the concession agreement ranged from 4.0 % to 5.65 % of total traffic volume for each operator. Although the proportion of vehicles exempted from sunset traffic increased from 0.85 % in 2017 to 2.79 % in 2022, the reduction amount ratio reached 4.2 % (KRW 25.5 billion) of total traffic revenue in 2022. The escalating number of registered eco-friendly vehicles is gradually causing operating profit losses on private roads. In alignment with the government's policy to expand eco-friendly vehicles, it is imperative to consider including vehicles eligible for toll reductions listed under the sunset category for subsidy payments. The study established a minimum ratio for toll reduction assistance at 4.0 %, agreed upon between the road authorities and private operators. Three policy alternatives were proposed to ensure preservation of amounts exceeding this threshold for sustaining adequate toll revenue for private road operators.

• Journal of Korea Port Economic Association
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• v.40 no.1
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• pp.151-163
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• 2024

This study sought to confirm the impact of analytical methods and behavioral economic theory factors on decision-making when making chartering decisions in the dry bulk shipping market. This study on chartering decision-making model was began to verify why shipping companies do not make rational decision-making and behavior based on analytical methods such as freight prediction and process of alternative selection in the same market situation. To understand the chartering decision-making model, it is necessary to study the impact of behavioral economic theory such as heuristics, loss aversion, and herding behavior on chartering decision-making. Through AHP analysis, the importance of the method factors relied upon in chartering decision-making. The dependence of the top factors in chartering decision-making was in the following order: market factors, heuristics, internal factors, herding behavior, and loss aversion. Market factors, heuristics, and internal factors. As for detailed factors, spot freight index and empirical intuition were confirmed as the most important factors relied on when making decisions. It was confirmed that empirical intuition is more important than internal analysis, which is an analytical method. This study can be said to be meaningful in that it academically researched and proved the bounded rationality of humans, which cannot be fully rational, and sometimes relies on experience or psychological tendencies, by applying it to the chartering decision-making model in the dry bulk shipping market. It also suggests that in the dry bulk shipping market, which is uncertain and has a high risk of loss due to decision-making, the experience and insight of decision makers have a very important impact on the performance and business profits of the operation part of shipping companies. Even though chartering are a decision-making field that requires judgment and intuition based on heuristics, decision-makers need to be aware of this decision-making model in order to reduce repeated mistakes of deciding contrary to market situation. It also suggests that there is a need to internally research analytical methods and procedures that can complement heuristics such as empirical intuition.

• Journal of The Korean Association For Science Education
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• v.44 no.4
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• pp.325-341
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• 2024

This study examined how specific aspects of epistemic cognition are developed in elementary students during modeling activities, using the Apt-AIR framework. The study focused on a class unit titled 'Shall We Find Out What the Landscape of a Riverside Looks Like?' which is part of the land chapter in the third-grade Korean elementary science curriculum. Ambitious Science Teaching (AST) was applied as a teaching strategy to enhance students' model construction. Seven science classes were conducted in line with the core practices of AST, with 29 elementary school students participating in the study. The classes were organized into four stages: initial model composition, inquiry activity, group model composition-sharing, and final model construction. The class activities at each stage were analyzed using both the AIR model, i.e., epistemic aim and value (A), epistemic ideals (I), and reliable epistemic processes (R), and the multi-faceted framework for epistemic thinking from the Apt-AIR framework. The results of the study revealed that in science classes emphasizing modeling activities based on the core practices of AST, the elementary students progressively developed more sophisticated explanatory models that included causal relationships explaining the topographic differences between the upstream and downstream sections of a river. This result was due to their engagement in constructing initial models to describe phenomena, supplementing the initial models using data collected in the model experiment, and participating in discussions to share and evaluate group models. Additionally, from the perspective of the Apt-AIR framework, the aspects of epistemic cognition demonstrated by the elementary students in their modeling activities were appropriate for engaging with cognitive processes related to epistemic aims and values, epistemic ideals, and reliable processes. The other four aspects of the Apt-AIR framework, however, were not performed as effectively. In particular, the application of reliable epistemic processes for knowledge construction required more improvement.

• Journal of Bio-Environment Control
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• v.33 no.1
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• pp.30-36
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• 2024

This study was conducted to determine the optimal working conditions when a recently developed blower-type onion stem cutter is utilized for cutting onion leaves at harvest time. The June 20 leaf cutting treatment group had the highest leaf dryness among the treatment groups (leaf dryness: 66.3%; leaf moisture content: 50.5%); the residual leaf length was 6.7 ± 3.5 cm. It is considered to have the best mechanical leaf cutting performance among the treatment groups because it is included in the optimal range of 4-10 cm. The average working speed of mechanical onion leaf cutting using the stem cutter was 0.17 m·s^-1, which is approximately 3.4 times faster than the average working speed of 0.05 m·s^-1 in the human leaf cutting treatment group. This is expected to save approximately 2.6 hours compared to human labor (based on one person) when working on a 10a area using this machine. In addition, the incidence of damaged bulbs in the machine leaf cutting treatment group was 1.3%, compared to 0.0% in the manual leaf cutting treatment group. This suggests that the mechanical leaf cutting treatment group had a higher average onion bulb decay rate during storage than the manual leaf cutting treatment group. When the storage characteristics of each treatment group were examined, the decay rate by bulb part (leaf connected or root connected) after 8 months of storage was higher in the treatment group with a residual leaf length of less than 5.0 cm after mechanical leaf cutting than in the treatment with a residual leaf length of more than 5.0 cm. This is thought to be due to the fact that treatments with a residual leaf length of less than 5.0 cm are more susceptible to infection by pathogens that cause decay during storage than treatments with a residual leaf length of 5.0 cm or more. Based on the results of this experiment, performance target of the experimental machine (residual leaf length after operation: 5 cm), and existing research on the optimal residual leaf length for onion harvesting, it is recommended to cut onion leaves so that the residual leaf length is 5-10 cm when using the stem cutter.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.4
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• pp.243-254
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• 2024

In recent years, as support for venture companies and performance increase, investment scale increases. To support them goverment operates venture firm confirmation system as a part of a variety of policies. Many studies suggest venture confirmation system offer the practical assistance on performance of venture companies. However, simply venture firm confirmation system affects on performance of venture companies. This study sought to develop a theoretical research model about the impact of innovation capabilities and industrial property rights on venture companies' financial performance and technological capabilities through the venture company confirmation system. The following hypotheses were tested. First, the innovation capabilities of venture companies such as development capability, manufacturing capability, marketing capability, level of cost leadership, level of high added value, degree of clarity of business model, and degree of innovation of business model have a significant impact on the venture company confirmation system. Second, the industrial property rights of venture companies, such as the number of domestic industrial property rights, foreign industrial property rights, industrial property rights in domestic applications, and industrial property rights in overseas applications, do not have a significant impact on the venture business confirmation system. Third, the benefits of the venture business confirmation system, such as promotion of technology development, advertising effects, tax benefits, securing excellent human resources, financing and investment incentives, advantageous participation in government support systems, and deregulation, are related to the financial performance of venture businesses such as sales and operating profit., net profit and technological level. Lastly, it was confirmed that, except for research and development type venture companies, innovation capabilities and industrial property rights do not have a significant impact on financial performance and technological capabilities through the venture confirmation system. The implications of this study mean that in situations where a company's innovation capabilities are lacking, the supply and demand of the venture business confirmation system is weak. Therefore, in order to improve the benefits of the venture business verification system, it is necessary to operate the venture business verification system benefits mainly for companies with high corporate capabilities. Next, it means that industrial property rights are not related to the venture business confirmation system. Therefore, there will be no need to consider industrial property rights as an important matter in the certification of the venture business verification system. Lastly, the higher the level of benefits from the venture business confirmation system, the greater the company's performance and technological capabilities. Therefore, efforts should be made to utilize the venture business verification system in a way that can improve performance or technology through the benefits of the venture business verification system.

• Journal of the Korea Society of Computer and Information
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• v.29 no.9
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• pp.125-136
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• 2024

This study presents an automated Python algorithm for analyzing rainfall characteristics to establish critical rainfall thresholds as part of a landslide early warning system. Rainfall data were sourced from the Korea Meteorological Administration's Automatic Weather System (AWS) and the Korea Forest Service's Automatic Mountain Observation System (AMOS), while landslide data from 2020 to 2023 were gathered via the Life Safety Map. The algorithm involves three main steps: 1) processing rainfall data to correct inconsistencies and fill data gaps, 2) identifying the nearest observation station to each landslide location, and 3) conducting statistical analysis of rainfall characteristics. The analysis utilized power law and nonlinear regression, yielding an average R² of 0.45 for the relationships between rainfall intensity-duration, effective rainfall-duration, antecedent rainfall-duration, and maximum hourly rainfall-duration. The critical thresholds identified were 0.9-1.4 mm/hr for rainfall intensity, 68.5-132.5 mm for effective rainfall, 81.6-151.1 mm for antecedent rainfall, and 17.5-26.5 mm for maximum hourly rainfall. Validation using AUC-ROC analysis showed a low AUC value of 0.5, highlighting the limitations of using rainfall data alone to predict landslides. Additionally, the algorithm's speed performance evaluation revealed a total processing time of 30 minutes, further emphasizing the limitations of relying solely on rainfall data for disaster prediction. However, to mitigate loss of life and property damage due to disasters, it is crucial to establish criteria using quantitative and easily interpretable methods. Thus, the algorithm developed in this study is expected to contribute to reducing damage by providing a quantitative evaluation of critical rainfall thresholds that trigger landslides.

• Journal of Korean Society of Forest Science
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• v.20 no.1
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• pp.1-44
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• 1973

Needless to say, the management of national forest in all countries is very important in view of the national mission and management purposes. Korean national forest is also in particular significant in promoting national economy for the continuous increasing of the demand for wood, conservation of the land and social welfare. But there's no denying the fact that the leading aim of the Korean forest policy has been based upon the conservation of forest resources and recovery of land conservation function instead of improvement of the forest productive capacity. Therefore, the management of national forest should be aimed as an industry in the chain of the Korean national economy. And the increment of the forest productive capacity based on rationalized forest management is also urgently needed. Not only the increment of the timber production but also the establishment of the good forest in quality and quantity are to bring naturally many functions of conservation and other public benefits. In 1908 Korean national forest was historically established for the first time as a result of the notification for ownership, and was divided into two kinds in 1911-1924, such as indisposable national forest for land conservation, forest management, scientific research and public welfare, and the other national forest to be disposed. Indisposable forest is mostly under the jurisdiction of national forest stations (Chungbu, Tongbu, Nambu), and the tother national forests are under custody of respective cities and provinces, and under custody of the other government authorities. As of the end of 1971, national forest land is 19.5% (1,297,708 ha) of the total forest land area, but growing stock is 50.1% ($35,406,079m^3$) of the total forest growing stock, and timber production of national forest is 23.6% ($205,959m^3$) of the year production of total timber in Korea. Accordingly, it is the important fact that national forest occupies the major part of Korean forestry. The author positively affirms that success or failure of the management of national forest controls rise or fall of forestry in Korea. All functions of forest are very important, but among others the function of timber production is most important especially in Korea, that unavoidably imports a large quantity of foreign wood every year (in 1971 import of foreign wood-$3,756,000m^3$, 160,995,000 dollars). So, Korea urgently needs the improvement of forest productive capacity in national forest. But it is difficult that wood production meets the rapid increase of demand for wood to the development of economy, because production term of forestry is long, so national forest management should be rationalized by the effective investment and development of forestry techniques in the long view. Although Korean national forest business has many difficulties in the budget, techniques and the lack of labour due to outflow of rural village labour by development of national economy, and the increase of labour wages and administrative expenses etc. the development of national forest depends on adoption of the suitable forest techniques and management adapted for social and economical development. In this view point the writer has investigated and analyzed the status of the management of national forest in Korea to examine the irrational problems and suggest an improvement plan. The national forestry statistics cited in this study is based on the basic statistics and the statistics of the forest business as of the end of 1971 published by Office of Forestry, Republic of Korea, and the other depended on the data presented by the national forest stations. The writer wants to propose as follows (seemed to be helpful in improvement of Korean national forest management). 1) In the organization of national forest management, more national forest stations should be established to manage intensively, and the staff of working plan officials should be strengthened because of the importance of working plan. 2) By increasing the staff of protection officials, forest area assigned for each protection official should be decreased to 1,000-2,000 ha. 3) The frequent personnel changes of supervisor of national forest station(the responsible person on-the-spot) obstructs to accomplish the consistent management plan. 4) In the working plan drafting for national forest, basic investigations should be carefully practiced with sufficient expenditure and staff not to draft unreal working plan. 5) The area of working-unit should be decreased to less than 2,000 ha on the average for intensive management and the principle of a working-unit in a forest station should be realized as soon as possible. 6) Reforestation on open land should be completed in a short time with a debt of the special fund(a long term loan), and the land on which growing hardwood stands should be changed with conifers to increase productivity per unit area, and at the same time techical utilization method of hardwood should be developed. 7) Expenses of reforestation should be saved by mechanization and use of chemicals for reforestation and tree nursery operation providing against the lack of labour in future. 8) In forest protection, forest fire damage is enormous in comparison with foreign countries, accordingly prevention system and equipment should be improved, and also the minimum necessary budget should be counted up for establishment and manintenance of fire-lines. 9) Manufacture production should be enlarged to systematize protection, processing and circulation of forest business, and, by doing this, mich benefit is naturally given for rural people. 10) Establishment and arrangement of forest road networks and erosion control work are indispensable for the future development of national forest itself and local development. Therefore, these works should be promoted by the responsibility of general accounting instead of special accounting. 11) Mechanization of forest works should be realized for exploiting hinterlands to meet the demand for timber increased and for solving lack of labour, consequently it should promote import of forest machines, home production, training for operaters and careful adminitration. 12) Situation of labour in future will grow worse. Therefore, the countermeasure to maintain forest labourers and pay attention to public welfare facilities and works should be considered. 13) Although the condition of income and expenditure grows worse because of economical change, the regular expenditure should be fixed. So part of the surplus fund, as of the end of 1971, should be established for the fund, and used for enlarging reforestation and forest road networks(preceding investment in national forest).

• Journal of Distribution Research
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• v.15 no.3
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• pp.71-110
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• 2010

1. Introduction Today Internet is recognized as an important way for the transaction of products and services. According to the data surveyed by the National Statistical Office, the on-line transaction in 2007 for a year, 15.7656 trillion, shows a 17.1%(2.3060 trillion won) increase over last year, of these, the amount of B2C has been increased 12.0%(10.2258 trillion won). Like this, because the entry barrier of on-line market of Korea is low, many retailers could easily enter into the market. So the bigger its scale is, but on the other hand, the tougher its competition is. Particularly due to the Internet and innovation of IT, the existing market has been changed into the perfect competitive market(Srinivasan, Rolph & Kishore, 2002). In the early years of on-line business, they think that the main reason for success is a moderate price, they are awakened to its importance of on-line service quality with tough competition. If it's not sure whether customers can be provided with what they want, they can use the Web sites, perhaps they can trust their products that had been already bought or not, they have a doubt its viability(Parasuraman, Zeithaml & Malhotra, 2005). Customers can directly reserve and issue their air tickets irrespective of place and time at the Web sites of travel agencies or airlines, but its empirical studies about these Web sites for reserving and issuing air tickets are insufficient. Therefore this study goes on for following specific objects. First object is to measure service quality and service recovery of Web sites for reserving and issuing air tickets. Second is to look into whether above on-line service quality and on-line service recovery have an impact on overall service quality. Third is to seek for the relation with overall service quality and customer satisfaction, then this customer satisfaction and loyalty intention. 2. Theoretical Background 2.1 On-line Service Quality Barnes & Vidgen(2000; 2001a; 2001b; 2002) had invented the tool to measure Web sites' quality four times(called WebQual). The WebQual 1.0, Step one invented a measuring item for information quality based on QFD, and this had been verified by students of UK business school. The Web Qual 2.0, Step two invented for interaction quality, and had been judged by customers of on-line bookshop. The WebQual 3.0, Step three invented by consolidating the WebQual 1.0 for information quality and the WebQual2.0 for interactionquality. It includes 3-quality-dimension, information quality, interaction quality, site design, and had been assessed and confirmed by auction sites(e-bay, Amazon, QXL). Furtheron, through the former empirical studies, the authors changed sites quality into usability by judging that usability is a concept how customers interact with or perceive Web sites and It is used widely for accessing Web sites. By this process, WebQual 4.0 was invented, and is consist of 3-quality-dimension; information quality, interaction quality, usability, 22 items. However, because WebQual 4.0 is focusing on technical part, it's usable at the Website's design part, on the other hand, it's not usable at the Web site's pleasant experience part. Parasuraman, Zeithaml & Malhorta(2002; 2005) had invented the measure for measuring on-line service quality in 2002 and 2005. The study in 2002 divided on-line service quality into 5 dimensions. But these were not well-organized, so there needed to be studied again totally. So Parasuraman, Zeithaml & Malhorta(2005) re-worked out the study about on-line service quality measure base on 2002's study and invented E-S-QUAL. After they invented preliminary measure for on-line service quality, they made up a question for customers who had purchased at amazon.com and walmart.com and reassessed this measure. And they perfected an invention of E-S-QUAL consists of 4 dimensions, 22 items of efficiency, system availability, fulfillment, privacy. Efficiency measures assess to sites and usability and others, system availability measures accurate technical function of sites and others, fulfillment measures promptness of delivering products and sufficient goods and others and privacy measures the degree of protection of data about their customers and so on. 2.2 Service Recovery Service industries tend to minimize the losses by coping with service failure promptly. This responses of service providers to service failure mean service recovery(Kelly & Davis, 1994). Bitner(1990) went on his study from customers' view about service providers' behavior for customers to recognize their satisfaction/dissatisfaction at service point. According to them, to manage service failure successfully, exact recognition of service problem, an apology, sufficient description about service failure and some tangible compensation are important. Parasuraman, Zeithaml & Malhorta(2005) approached the service recovery from how to measure, rather than how to manage, and moved to on-line market not to off-line, then invented E-RecS-QUAL which is a measuring tool about on-line service recovery. 2.3 Customer Satisfaction The definition of customer satisfaction can be divided into two points of view. First, they approached customer satisfaction from outcome of comsumer. Howard & Sheth(1969) defined satisfaction as 'a cognitive condition feeling being rewarded properly or improperly for their sacrifice.' and Westbrook & Reilly(1983) also defined customer satisfaction/dissatisfaction as 'a psychological reaction to the behavior pattern of shopping and purchasing, the display condition of retail store, outcome of purchased goods and service as well as whole market.' Second, they approached customer satisfaction from process. Engel & Blackwell(1982) defined satisfaction as 'an assessment of a consistency in chosen alternative proposal and their belief they had with them.' Tse & Wilton(1988) defined customer satisfaction as 'a customers' reaction to discordance between advance expectation and ex post facto outcome.' That is, this point of view that customer satisfaction is process is the important factor that comparing and assessing process what they expect and outcome of consumer. Unlike outcome-oriented approach, process-oriented approach has many advantages. As process-oriented approach deals with customers' whole expenditure experience, it checks up main process by measuring one by one each factor which is essential role at each step. And this approach enables us to check perceptual/psychological process formed customer satisfaction. Because of these advantages, now many studies are adopting this process-oriented approach(Yi, 1995). 2.4 Loyalty Intention Loyalty has been studied by dividing into behavioral approaches, attitudinal approaches and complex approaches(Dekimpe et al., 1997). In the early years of study, they defined loyalty focusing on behavioral concept, behavioral approaches regard customer loyalty as "a tendency to purchase periodically within a certain period of time at specific retail store." But the loyalty of behavioral approaches focuses on only outcome of customer behavior, so there are someone to point the limits that customers' decision-making situation or process were neglected(Enis & Paul, 1970; Raj, 1982; Lee, 2002). So the attitudinal approaches were suggested. The attitudinal approaches consider loyalty contains all the cognitive, emotional, voluntary factors(Oliver, 1997), define the customer loyalty as "friendly behaviors for specific retail stores." However these attitudinal approaches can explain that how the customer loyalty form and change, but cannot say positively whether it is moved to real purchasing in the future or not. This is a kind of shortcoming(Oh, 1995). 3. Research Design 3.1 Research Model Based on the objects of this study, the research model derived is