• Geomechanics and Engineering
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• v.28 no.5
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• pp.531-546
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• 2022

Ground displacements caused by the construction of overlapping twin shield tunnels with small turning radius are complex, especially under special geological conditions of construction. To investigate the ground displacements caused due to shield machines in the unique calcareous sand layers in Israel for the first time and determine the main factors affecting the ground displacements, field monitoring, laboratory geological analysis, theoretical calculations, and parameter studies were adopted. By using rod extensometers, inclinometers, total stations, and automatic segment-displacement monitors, subsurface tunneling-induced displacement, surface settlement, and displacement of the down-track tunnel segments caused by the construction of an up-track tunnel were analyzed. The up-track tunnel and the down-track tunnel pass through different stratum, resulting in different construction parameters and ground displacements. The laws of variation of thrust and torque, soil pressure in the chamber, excavated soil quantity, synchronous grouting pressure, and grout volume of the two tunnels from parallel to fully overlapping orientations were compared. The thrust and torque of the shield in the fine sand are larger than those in the Kurkar layer, and the grouting amount in fine sand is unstable. According to fuzzy statistics and Gaussian curve fitting of the shield tunneling speed, the tunneling speed in the Kurkar stratum is twice that in the fine-sand stratum.

• Geomechanics and Engineering
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• v.28 no.6
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• pp.547-557
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• 2022

Dune sands are poorly graded collapsible soils lacking fines. This experimental study explored the technical feasibility of sustainable invigoration of fine waste materials to improve the geotechnical properties of dune sand. The fine waste considered in this study is fine marble waste. The fine waste powder was mixed with dune sand at different contents (5, 10,15, 20, 25, 50%), where the gradation, void ratio, compaction, and shear strength characteristics were assessed for each fine marble waste -dune sand blend. The geotechnical properties of the dune sand-fine marble waste mix delineated in this study reveal the enhancement in compaction and gradation characteristics of dune sand. According to the results, the binary mixture of dune sand with 20% of fine marble waste gives the highest maximum dry density and results in shear strength improvement. In addition, a numerical study is conducted for the practical application of the binary mix in the field and tested for an isolated shallow foundation. The elemental analysis of the fine marble waste confirms that the material is non-contaminated and can be employed for engineering applications. Furthermore, the numerical study elucidated that the shallow surface replacement of the site with the dune sand mixed with 20% fine marble waste gives optimal performance in terms of stress generation and settlement behavior of an isolated footing. For a sustainable mechanical performance of the fine marble waste mixed sand, an optimum dose of 20% fine marble waste is recommended, and some correlations are proposed. Thus, for improving dune sand's geotechnical characteristics, the addition of fine marble waste to the dune sand is an environment-friendly solution.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.320-326
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• 2022

The use of the Internet has become commonplace for billions of people on the planet. The rapid development of technology, in particular, mobile gadgets, has provided access to communication anywhere, anytime. At the same time, there are growing concerns about the behavior of people on the Internet, in particular, towards each other and social groups in general. This raises the issue of human rights in today's information society. In this study, we focused on human rights such as the right to privacy, confidentiality, freedom of expression, the right to be forgotten, etc. We point to some differences in this regard, in particular between the EU, etc. In addition, we describe the latest legal regulation in this aspect in European countries. Such methods as systemic, factual, formal and legal, to show the factors of formation and development of human rights in the context of digitalization were used. The authors indicate which of them deserve the most attention due to their prevalence and relevance. Thus, we concluded that the technological development of social communications has laid the groundwork for a legal settlement of privacy and opinion issues on the Internet. Simultaneously, jurisdictions address issues on every aspect of human rights on the Internet, based on previous norms, case law, and principles of law. It is concluded that human rights legislation on the Internet will continue to be actively developed to ensure a balance of private and public interests, safe online access and unimpeded access to it.

• Journal of the Society of Disaster Information
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• v.19 no.1
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• pp.204-215
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• 2023

Purpose: In this study, it was proposed a plan to build the Continuous Preventive Audit System in the military Organization with the expectation that we will develop an efficient audit method under the rapidly changing audit and work environment in the future. Method: it was examined the realities and problems of the military self-audit, the cases of the Continuous Preventive Audit System currently being used by government departments and institutions and internal control inspection of the information system of the Foreign Audit Office. Result: Government departments, agencies, and foreign auditors have established a Continuous Preventive Audit System to overcome the problems and limitations of their own audits, ensuring accounting accident prevention and audit work efficiency and are focused on auditing internal controls of information systems. Conclusion: In the future, more specific studies on the design of detailed scenarios for each function of defense work and the research and analysis on the improvement of defense information system should be followed for the establishment and settlement of a more specific Continuous Preventive Audit System.

• Korean Journal of Community Nutrition
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• v.28 no.1
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• pp.1-10
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• 2023

Objectives: This study aimed to investigate the nutritional status and dietary behavior of adolescents from North Korean refugee (NKR) families residing in South Korea (SK), who are known to be at a higher risk of malnutrition due to their lower socioeconomic status and facing other psychological challenges. Methods: A total of 178 adolescents (91 males and 87 females) from NKR families were included in the analysis, and their demographic details such as age, birthplace, parental nationality, and duration of their settlement in SK were collected through questionnaires. Anthropometric measurements were also taken to determine their growth and nutritional status according to the 2017 Korean National Growth Charts for children and adolescents. The study used the Nutrition Quotient for Korean Adolescents (NQ-A) questionnaire to assess the dietary behavior of the participants. Results: Approximately 11.8% and 10.1% of participants were identified with malnutrition and obesity, respectively. The total mean score for the NQ-A was 50.1. The mean scores for the individual factors of balance, diversity, moderation, environment, and practice were 49.2, 44.7, 43.8, 51.2, and 61.5, respectively. Approximately 47.2% of participants had a low NQ-A grade. However, there was no significant difference in the NQ-A scores according to their nutritional status or duration of time in SK. Conclusions: Adolescents from NKR families exhibited both malnutrition and obesity. However, their dietary behavior, as assessed using the NQ-A, did not vary with their nutritional status. The unique challenges and related dietary behavior of North Korean adolescent refugees should be taken into consideration, when developing targeted strategies for nutritional education and health management programs.

• Journal of the Korean Geotechnical Society
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• v.22 no.2
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• pp.19-28
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• 2006

Long-term field observations were performed in three excavation sites in order to investigate the displacement behavior of adjacent ground during overall excavation procedure, where the depths of deep excavations were 15 m$\∼$29 m. In this study, ground settlements and lateral displacements of braced wall measured during installation of retaining wall and removal of bracing were specially focused to evaluate the behavior quantitatively according to three-stage-divided procedure, i.e. pre-excavation, main excavation, and removal of bracing. Through field measurements on three excavation sites, lateral displacements induced during removal of bracing are approximate to 40$\%$ of the amount found during main excavation stage and additional adjacent ground deformation during post-excavation procedure ranges from 18$\%$ to 33$\%$ of that found during main excavation stage, based on the settlement volume. In conclusion, it was quantitatively identified in this study that the deformations of adjacent ground during pre- and post-excavation stage were not negligible.

• Journal of the Korean Geotechnical Society
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• v.23 no.10
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• pp.151-161
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• 2007

EPS provides a superb self-sufficient stability. Studies on the process of EPS construction method focus on the inchoate phase of general construction, which is increasingly applied to construction sites throughout the world. Unfortunately, there has been little study on the durability and long-term soil behavior involving EPS materials. In this study, the boring, in-site and laboratory tests were conducted to examine the long-term soil behavior in the back-filling of alternating behind the side to which EPS was applied. And results of finite element analysis considering various test results and the soil behavior data measured during the construction show that EPS construction method is a superb process that relieves the load and consequently reduces the settlement, alleviates the stress on the abutment, and prevents lateral flow.

• Journal of the Korean Geotechnical Society
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• v.24 no.10
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• pp.45-55
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• 2008

In this study, the in-situ model test has been conducted to estimate and analyze consolidation behavior of the ground by using the miniature test that reconstructs economically geotechnical behavior of in-situ full scale structure. To analyze the relation of effective stress, void ratio and coefficient of permeability at the self-weight consolidation stage, the low stress seepage consolidation test has been conducted and the involution function of constitutive equation had been obtained from the result of the curve fitted seepage consolidation test. As a result of the numerical analysis that had been conducted on the representative section using a constitute equation, final settlement was similar to those of self-weight consolidation of the centrifugal model test. But it was more or less smaller. It seems that these trends are caused by the difference between estimated values.

• Journal of the Korean Geotechnical Society
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• v.22 no.5
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• pp.69-81
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• 2006

The micropile, which is a kind of the in-situ manufactured pile with small diameter of $150\sim300mm$, is constructed by installing a steel bar or pipe and injecting grout into a borehole. The application fields of micropile are being gradually expanded in a limited space of down-town area, because the micropile has various advantages with low vibration and noise in method and compact size in machine, etc. Mostly, the micropile has been applied to secure the safety of structures, depending on the increment of bearing capacity and the restraint of displacement. The micropile is expected to be used in various fields due to its effectiveness and potentiality in the future. The model test, focused on the interaction between micropile and soil in this study, was carried out. The micropile is installed in a soil adjacent to footing (concept of 'soil reinforcement'). With the test results and soil deformation analysis, the reinforcement effect (relating to bearing capacity and settlement) was analysed in a qualitative and quantitative manner, respectively. Consequently, it is expected that we nay demonstrate the improvement of an efficiency and application in the design and construction of micropile.

• Journal of the Korean Geotechnical Society
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• v.24 no.12
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• pp.93-101
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• 2008

This paper presents the results of numerical investigation on support mechanism of geogrid-encased stone columns for use in soft ground improvement. A number of cases were analyzed using a 3D stress-pore pressure coupled model that can effectively model construction sequence and drainage as well as reinforcing effects of geogrid-encased stone columns. The results indicated that the geogrid encasement provides additional confinement effect that reduces vertical stress in the soft ground, thus resulting in less excess pore water pressures and associated settlement. Also revealed was that such a confinement effect depends on encasement length and stiffness of geogrid. It is also shown that there exist critical encasement length and stiffness of geogrid for a given condition.