• Current Optics and Photonics
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• v.8 no.1
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• pp.45-55
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• 2024

A fiber spool with ultra-low vibration sensitivity has been demonstrated for the ultra-narrow-linewidth fiber-stabilized laser by the multi-object orthogonal experimental design method, which can achieve the optimization object and analysis of influence levels without extensive computation. According to a test of 4 levels and 4 factors, an L₁₆ (4⁴) orthogonal table is established to design orthogonal experiments. The vibration sensitivities along the axial and radial directions and the normalized sums of the vibration sensitivities are determined as single objects and comprehensive objects, respectively. We adopt the range analysis of object values to obtain the influence levels of the four design parameters on the single objects and the comprehensive object. The optimal parameter combinations are determined by both methods of comprehensive balance and evaluation. Based on the corresponding fractional frequency stability of ultra-narrow-linewidth fiber-stabilized lasers, we obtain the final optimal parameter combination A3B1C2D1, which can achieve the fiber spool with vibration sensitivities of 10^-12/g magnitude. This work is the first time to use an orthogonal experimental design method to optimize the vibration sensitivities of fiber spools, providing an approach to design the fiber spool with ultra-low vibration sensitivity.

• Geomechanics and Engineering
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• v.36 no.5
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• pp.427-440
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• 2024

This study concentrates on the 301 comprehensive caving working face, notable for its considerable mining height. The roof model is established by integrating prior geological data and the latest borehole rock stratum's physical and mechanical parameters. This comprehensive approach enables the determination of lithology, thickness, and mechanical properties of the roof within 50 m of the primary mining coal seam. Utilizing the transfer rock beam theory and incorporating mining pressure monitoring data, the study delves into the geometric parameters of the direct roof, basic roof movement, and roof pressure during the initial mining process of the 301 comprehensive caving working face. The direct roof of the mining working face is stratified into upper and lower sections. The lower direct roof consists of 6.0 m thick coarse sandstone, while the upper direct roof comprises 9.2 m coarse sandstone, 2.6 m sandy mudstone, and 2.8 m medium sandstone. The basic roof stratum, totaling 22.1 m in thickness, includes layers such as silty sand, medium sandstone, sandy mudstone, and coal. The first pressure step of the basic roof is 61.6 m, with theoretical research indicating a maximum roof pressure of 1.62 MPa during periodic pressure. Extensive simulations and analyses of roof subsidence and advanced abutment pressure under varying working face lengths. Optimal roof control effect is observed when the mining face length falls within the range of 140 m-155 m. This study holds significance as it optimizes the working face length in thick coal seams, enhancing safety and efficiency in coal mining operations.

• Journal of the Korean Society for Library and Information Science
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• v.48 no.4
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• pp.241-266
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• 2014

The purpose of this study is to investigate the importance and validity of the unified policy of the administrative system for the public library through the analysis and evaluation of the outcomes and plans about the policy on the first and second Comprehensive Library Advancement Plan. In addition, this study seeks to the strategies for the public library administrative system unification by reviewing the issue details of the unification strategies. The first Comprehensive Library Advancement Plan was found to be just proclamatory without concrete and practical results through its performance analysis. The policy tasks were evaluated to lack in feasibility and specificity in the second Comprehensive Library Advancement Plan which was performed on a group of library professionals. Policy decision to determine who would be responsible for the unification into the local government was found to be valid by the results of previous research findings, policy evaluation by experts and in-depth interview survey for field practitioners. Substantial and detailed action-oriented strategy rather than bluffing and macro policy is necessary for the unification of the library administrative system. It is because we have found there exist significant issues in terms of unified approach, structure of the organization, personnel transfer and grade adjustment, property transfer, etc. through the analysis.

• Journal of the Ergonomics Society of Korea
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• v.35 no.6
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• pp.473-492
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• 2016

Objective: This paper discusses the recent challenges to human factors engineering due to the safety culture. Background: As incidents occurring in specific fields such as logistics, plant, energy and medical sectors in Korea, as well as in the public sectors including railway, road, aviation and shipping, are recently raised as social issues from the disaster dimension, those incidents are dealt with as man-made disasters in many cases. The trend regarding all accidents as man-made disasters has been expanded in the active perspective that the controllability of all incidents should be ensured in technology development, due to change from a fatal point of view regarding disasters as random occurrence of uncertainties in the past. Method: Man-made disasters are concluded as human errors, and safety culture stands out as a cause of human errors or a new cause item recently. Because safety culture, however, is a very comprehensive term, of which true nature is obscure, although many definitions of safety culture have been presented, the safety culture may make avoid the true nature and responsibility of an incident, or make the main player and subject obscure. Raising safety culture as a cause without presenting a specific countermeasure will be just a wisdom of hindsight. Results and Conclusion: This study reviews the fundamental discussions on "Is safety culture a task of human factors engineering?" and the existing approach carried out from various perspectives in order to seek an effective approach on the new task of safety culture in the human factors engineering field. This study discusses an engineering approach to meet a precondition that safety culture is not just an added factor through a review of the approaches in the proactive fields such as nuclear power and aviation, and the traditional approaches of human factors engineering. Application: This study especially defines the perspective of socio-technological system that has expanded the existing man-machine system, and discusses a systemic approach embracing various interactions, and several overriding tasks.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.9
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• pp.2665-2691
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• 2024

The philosophy of Zero Trust in cybersecurity lies in the notion that nothing assumes to be trustworthy by default. This drives defense organizations to modernize their cybersecurity architecture through integrating with the zero-trust principles. The enhanced architecture is expected to shift protection strategy from static and perimeter-centric protection to dynamic and proactive measures depending on the logical contexts of users, assets, and infrastructure. Given the domain context of defense environment, we aim three challenge problems to tackle and identify four technical approaches by the security capabilities defined in the Zero Trust Architecture. First approach, dynamic access control manages visibility and accessibility to resources or services with Multi Factor Authentication and Software Defined Perimeter. Logical network separation approach divides networks on a functional basis by using Software Defined Network and Micro-segmentation. Data-driven analysis approach enables machine-aided judgement by utilizing Artificial Intelligence, User and Entity Behavior Analytics. Lastly, Security Awareness approach observes fluid security context of all resources through Continuous Monitoring and Visualization. Based on these approaches, a comprehensive study of modern technologies is presented to materialize the concept that each approach intends to achieve. We expect this study to provide a guidance for defense organizations to take a step on the implementation of their own zero-trust architecture.

• Land and Housing Review
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• v.6 no.2
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• pp.89-99
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• 2015

What is a role of the studies on spatial planning of Korean peninsular and its cities in the process of cooperation between and unification of South and North Korea? Where should the basic perspectives be oriented for the process? Can a comprehensive plan of North Korea have practical implications although South-North cooperation does not get into its stride? If it can, which contents should the plan cover? This study aims to contemplate these issues and to suggest a preliminary land development approach of North Korea, which would contribute academic and practical debates on the issues, at this juncture of the cascade of studies on spatial planning in North Korea. It assume South-North relation would evolve from 'reconciliation and cooperation' and 'confederation' into 'unification' of South and North Korea which is based on the official plan of South Korea. We suggest, as the basic perspectives of development approach, cooperation(or co-evolution), future-oriented sustainability, and parallel development of industry and physical infrastructure. The development potential of North Korea is explained by detail fields and sub-regions, which is used to analyse SWOT and to subsequently extract the basic directions(vision and strategies) of North Korea development. These directions are followed by the spatial structure plan to improve North Korea using the potential of the regions. Based on the plan, the development directions of detail fields are suggested.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.41
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• pp.3-21
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• 2009

To understand the procedure of international commercial transaction clearly and logically, this author would like to emphasize the contractual approach in this paper. The main contract in the transaction is the contract of sale; to perform this contract, the three subordinate or supporting contracts(including the contract of carriage, the contracts of insurance and the contract of payment) should be followed and performed. In the contract of sale, besides the express Terms, the trade Terms have very comprehensive meanings. Each trade term in Incoterms(2000) deals with the matters relating to the rights and obligations of the parties to the contract of sale with respect to the delivery of the goods sold. It also provides for the duties of seller or buyer relating to the contract of carriage, the contract of insurance and the payment in the process of the delivery of goods. Especially, it does not provide the methods of payment concretely, but it imposes the seller to hand over the documents evidencing the conformity of the contract of sale, and the delivery which includes the documents of carriage and/or insurance. Thus although the trade Terms deal with the obligations of the seller or buyer directly, they are very closely related with the contract of carriage and the contract of insurance indirectly, and also with contract of payment using the documentary draft. For the Arbitration or the litigation in the case of the breach of contract, the trade Terms play very significant roles. When an arbitrator or a judge decides the case, they should understand each obligation clearly, in which case, the trade terms give answers about who is wrong or who is right. Therefore, the contractual approach focusing on the trade terms would give very fruitful advantages to the students or teachers in understanding the procedure of the international commercial transaction systematicly and comprehensively.

• Journal of KIISE:Software and Applications
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• v.31 no.5
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• pp.543-554
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• 2004

In Requirements engineering, requirements elicitation and analysis are very important tasks to develop software systems successfully. Even though various methods have been proposed including scenario-based analysis, goal based analysis, and coupling goal with scenario, each method has its own strengths and weaknesses. If you use only one method, it is very difficult to elicit and to analyze system requirements completely. Since these methods don't support a comprehensive elicitation process, this paper proposes an integrated approach. This integrated approach is focused on two viewpoints. One is what factors are comprised and the other is how they are integrated. This paper also shows how the proposed approach can be applied to Meeting Reservation System (MRS) development. An experiment has been conducted using this approach to demonstrate how complete requirements are elicited and analyzed and to show relative time savings during elicitation in comparison to each method.

• Korean Journal of Labor Studies
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• v.24 no.3
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• pp.1-34
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• 2018

This paper attempts to provide a new theoretical approach and an empirical analysis based on it to interrogate the structure of household income inequality and its changes in South Korea in the 2010s. Previous research on inequality in sociology, labor economics and feminism has focused on local inequalities which derive from specific spaces of society. For a comprehensive understanding of social inequality in totality, it requires a discussion of global inequality beyond local inequalities. Thus, a synthetic approach that integrates local inequalities, encompassing class, the labor market, population, and family. By using regression-based inequality decomposition, we decompose the contribution of gender, level of education, employment status, occupation, household composition and wealth to household income inequality. This paper shows that household and wealth, as well as the factors discussed in the previous research, are significant factors affecting household income inequality in South Korea.

• KIPS Transactions on Software and Data Engineering
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• v.8 no.3
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• pp.129-136
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• 2019

There are a variety of entities in natural language such as people, organizations, places, and products. These entities can have many various meanings. The ambiguity of entity is a very challenging task in the field of natural language processing. Entity Linking(EL) is the task of linking the entity in the text to the appropriate entity in the knowledge base. Pairwise based approach, which is a representative method for solving the EL, is a method of solving the EL by using the association between two entities in a sentence. This method considers only the interdependence between entities appearing in the same sentence, and thus has a limitation of global interdependence. In this paper, we developed an Entity2vec model that uses Word2vec based on knowledge base of RDF type in order to solve the EL. And we applied the algorithms using the generated model and ranked each entity. In this paper, to overcome the limitations of a pairwise approach, we devised a pairwise approach based on comprehensive interdependency and compared it.