• Structural Engineering and Mechanics
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• v.86 no.1
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• pp.119-137
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• 2023

The purpose of this research is to assess the performance of CBN and ceramic tools during the dry turning of gray cast iron EN GJL-350. During the turning operation, the variable machining parameters are cutting speed, feed rate, depth of cut and type of the cutting material. This contribution consists of two sections, the first one deals with the performance evaluation of four materials in terms of evolution of flank wear, surface roughness (2D and 3D) and cutting forces. The focus of the second section is on statistical analysis, followed by modeling and optimization. The experiments are conducted according to the Taguchi design L₃₂ and based on ANOVA approach to quantify the impact of input factors on the output parameters, namely, the surface roughness (Ra), the cutting force (Fz), the cutting power (Pc), specific cutting energy (Ecs). The RSM method was used to create prediction models of several technical factors (Ra, Fz, Pc, Ecs and MRR). Subsequently, the desirability function approach was used to achieve a multi-objective optimization that encompasses the output parameters simultaneously. The aim is to obtain optimal cutting regimes, following several cases of optimization often encountered in industry. The results found show that the CBN tool is the most efficient cutting material compared to the three ceramics. The optimal combination for the first case where the importance is the same for the different outputs is Vc=660 m/min, f=0.116 mm/rev, ap=0.232 mm and the material CBN. The optimization results have been verified by carrying out confirmation tests.

• Journal of Aerospace System Engineering
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• v.16 no.1
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• pp.70-80
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• 2022

An aerial refueling provides for extension of operational time and range for aircraft and enhances mission effectiveness, hence it application by most military aircrafts. The receiver aircraft should have the aerial refueling clearance that is established by performing technical and operational compatibility assessments to certify it for aerial refueling with a specific tanker model. The compatibility assessment includes aerial refueling handling qualities, functional, fuel, lighting system testing and it is finally verified through flight testing. However, since aerial refueling compatibility assessments have never been performed in Korea, there is no experience to determine the test requirements and the scope and size of the test program for a new development aircraft. This paper therefore introduces the common techniques of aerial refueling and aerial refueling flight test methods to understand the aerial refueling FCS (Flight Control System), OFP (operational flight program) and system validation, and aerial refueling envelope clearance of a fixed wing aircraft for a boom and receptacle refueling system that is being introduced into Korea Air Force.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5C
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• pp.217-228
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• 2009

In case of application of electrophoresis method for leakage restoration of waste impoundment, main points of consideration were to evaluate the mobility of clay particles by electrophoretic force and capacity of leakage repair in leachate electrolyte system contained with various chemical species. However, the flocculation phenomena of clay particles induced by electrochemical interaction between various chemical species and clay particles would cause the big problems in electrophoresis method. Therefore, a series of laboratory tests such as one-dimensional electrophoresis and gravitational experiments were carried out in order to identify the specific chemical species affected flocculation of clay particles and the range of chemical concentration in leachate. In addition, the characteristics of clay particle behavior with chemical species and concentration range in leachate were analized using the concept of the settling velocity, zeta potential, and electrophoretic velocity.

• Journal of the Korea Society of Computer and Information
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• v.28 no.11
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• pp.209-226
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• 2023

Cross-border e-commerce has emerged as a crucial force in stabilizing China's foreign trade, driving the transformation and upgrade of China's foreign trade, and contributing to global economic development and stability. As a result, promoting the high-quality development of cross-border e-commerce has become a common challenge within the Chinese industry. However, with the rapid growth of cross-border e-commerce, it faces new phenomena and challenges, such as a mix of quality, fierce competition, and price competition. Brands serve as distinguishing markers for identifying entities, and brand building is a prudent choice for achieving high-quality development in cross-border e-commerce. This article utilizes brand theory, employing a combined qualitative and quantitative approach, with a specific focus on key elements within the operations of cross-border e-commerce enterprises. Through an analysis of the key elements influencing the formation and development of brands within the internal operations of Chinese cross-border e-commerce enterprises, it investigates their internal formation mechanisms and assesses the significance of these critical factors in influencing brand formation. The research process is based on data from overseas consumers, conducting empirical analysis, ultimately providing certain guidance for brand development in cross-border e-commerce enterprises.

• Korea Trade Review
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• v.47 no.6
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• pp.335-353
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• 2022

There are two aspects of digital trade: the digitalisation of goods/services being traded and the digitalisation of the transactional act. Digital data (i.e. machine-readable industrial data and transactional data) is the major driving force for both aspects of digital trade. Digital data is a non-rivalrous input, whether for production or marketing activities, and is thus able to be used by many firms or government agencies without limiting the use of others. Digital platforms provide online infrastructure for the interactions between groups, for instance, consumers and producers. The externality effect refers to the situation in which prosperity in one group on a given platform will improve the returns of other groups on the same platform. In the era of the data-driven economy, strategic trade policy can involve data-related policies. The major objective of these policies is to improve the competitiveness of domestic firms. For instance, firms may be subsidised if they use cloud services provided by specific platforms. This strand of strategic trade policies might be useful for increasing the competitiveness of small-and medium-sized enterprises (SMEs) via the digitalisation of production/marketing processes. Alternatively, strategic trade policy may also exploit the externality effect via platform economy-related policies. Further, some countries may form data coalitions to facilitate cross-border data flow. This paper uses cases in Asian countries to illustrate which role these strategic trade policies can play in the digital economy.

• International Journal of Computer Science & Network Security
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• v.23 no.10
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• pp.57-66
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• 2023

Since 2009, Morocco has had a law governing the processing of personal data, the law 09-08, and a supervisory authority, the CNDP (National Commission for the Protection of Personal Data). Since May 2018, the European General Regulation on the Protection of Personal Data (GDPR) entered into force, which applies outside the EU in certain cases and therefore to certain Moroccan companies. The question of the protection of personal data is primarily addressed to the customer. The latter may not only be a victim of crime linked to ICT, but also have to face risks linked to the collection and abusive processing of his personal data by the private and public sectors. Often the customer does not really know how their data is stored, nor for how long and for what purpose. This fact raises the question of satisfying customer requirements, in particular for organizations that have adopted a quality approach based on ISO 9001 standard.In order to master these constraints, Moroccan companies have to adopt strategies based on modern quality management techniques, especially the adoption of principles issued from the international standard ISO 9001 while being confirmed by the law 09-08. It is through ISO 9001 and the law 09-08 that these companies can refer to recognized approaches in terms of quality and compliance. The major challenge for these companies is to have a Quality approach that allows the coexistence between the law 09-08 and ISO 9001 standard and this article deals within this specific context.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.5
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• pp.320-331
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• 2023

In this study, a model test was conducted using the soft-mooring technique to evaluate the added resistance of the ship in waves. The study also examined the specific factors that should be considered during the soft-mooring test. The main purpose of soft-mooring is to prevent drifting caused by waves by providing horizontal restoring forces. However, it can also create undesired restoring forces in the vertical direction. Therefore, we examined the restoring force of the ship's 6-DOF motion based on the arrangement of the soft-mooring and the height of the mooring connection point. We also checked the corresponding resonance period and drift distance. The soft-mooring test was conducted twice, once with self-propulsion and once without self-propulsion, allowing us to review the advantages and disadvantages of each test technique. The main parameters measured in these model tests were 6DOF motion and added resistance on the ship. We compared these measurements obtained from two different techniques (with and without self-propulsion). Additionally, we also compared the measurements based on the types of measuring sensors used (2D load cells on FP, AP, and 1D load cells on each mooring line) as well as the height of the mooring connection point.

• Journal of the Korean Society of Safety
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• v.38 no.5
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• pp.36-42
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• 2023

In this study, 50 ABE-type hard hats were procured from five certified commercial manufacturers, and shock absorption tests were conducted in accordance with Protective Equipment Safety Certification Notice No. 2020-35. The tests were performed under both high- and low-temperature conditions, adhering to safety helmet testing standards. The highest shock transmission ranges were recorded in the tests, with an average energy range of 2,600-4,108 N at high temperatures and 2,316-3,991 N at low temperatures. All five hard hat models demonstrated a maximum transmitted impact force below 4,450 N, without any loss of cap and attachment functionality, confirming their compliance with performance standards. Furthermore, we evaluated the side impact performance of the safety helmets of each company, with an average range of 4,722-5,267 N. Company A exhibited the lowest measurement at 4,722 N. Comparing these results with international safety standards and the national shock absorption test criteria, it was observed that the maximum transmitted shock value using government-specified impact weight falls within the range of 4,450-5,000 N. However, it was noted that developed countries have established specific standards for the side impact forces on safety helmets, which are legally mandated. Consequently, it is imperative for South Korea to enhance its safety helmet side impact performance test methodology to align with domestic standards in the future.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.27 no.1
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• pp.55-70
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• 2024

The loss of biodiversity poses a significant threat not only to business sustainability and investment risk but also to societal well-being. Nature serves as a crucial driver for long-term business viability and economic prosperity. The Task Force on Nature-related Financial Disclosures (TNFD), established in September 2023, mandates that companies assess and disclose their impacts on nature. Despite this, many businesses lack a full understanding of their reliance on and impact upon natural capital and ecosystem services, leading to insufficient disclosures. This study evaluates the applicability of TNFD's assessment methodologies and indicators within a domestic context, highlighting the condition of nature and ecosystem services, and exploring potential synergies with national biodiversity policies. Our analysis suggests that TNFD necessitates a unique approach to the spatial and temporal data and methodologies traditionally employed in environmental impact assessments. This includes assessing the reciprocal influences of corporate activities on natural capital and ecosystem services via the LEAP framework. Moreover, in industries where the choice of specific indicators depends on unique sectoral traits, developing a standardized strategy for data and assessment indicators-adapted to local conditions-is crucial due to the variability in the availability of assessment tools and data. The proactive engagement of the private sector in ecosystem restoration projects is particularly promising for contributing towards national biodiversity objectives. Although TNFD is in its nascent phase, its global adoption by numerous companies signifies its potential impact. Successful implementation of TNFD is anticipated to deepen businesses' and financial institutions' understanding of natural capital and ecosystem services, thereby reinforcing their commitment to sustainable development.

• Korean Journal of Agricultural Science
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• v.51 no.1
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• pp.63-77
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• 2024

Yield monitoring systems have become integral to precision agriculture, providing insights into the spatial variability of crop yield and playing an important role in modern harvesting technology. This paper aims to review current research trends in yield monitoring systems, specifically designed for non-grain crops, including cabbages, radishes, potatoes, and tomatoes. A systematic literature survey was conducted to evaluate the performance of various monitoring methods for non-grain crop yields. This study also assesses both mass- and volume-based yield monitoring systems to provide precise evaluations of agricultural productivity. Integrating load cell technology enables precise mass flow rate measurements and cumulative weighing, offering an accurate representation of crop yields, and the incorporation of image-based analysis enhances the overall system accuracy by facilitating volumetric flow rate calculations and refined volume estimations. Mass flow methods, including weighing, force impact, and radiometric approaches, have demonstrated impressive results, with some measurement error levels below 5%. Volume flow methods, including paddle wheel and optical methodologies, yielded error levels below 3%. Signal processing and correction measures also play a crucial role in achieving accurate yield estimations. Moreover, the selection of sensing approach, sensor layout, and mounting significantly influence the performance of monitoring systems for specific crops.