• Korean Journal of Construction Engineering and Management
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• v.12 no.4
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• pp.59-69
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• 2011

Construction works have become larger and more complex, improving productivity by introducing Information Technology (IT) is pursued. In this circumstance, many different kinds of project management system is being introduced, and various IT technologies are applied such as Personal Digital Assistant (PDA), Bar Code, Radio Frequency Identification (RFID), Web Camera, and so on. However, these kinds of technologies might cause reprocessing of information and ineffectiveness of project because of lack of real time information processing technology or separation between construction sites and management offices. Therefore, this research aims to develop Application that can be applied efficiently for construction material management, by understanding problems of former management system with questionnaires and extracting functions with analysis of requirements. This will be possible to input information automatically, to process and check material information in real time, and to identify the location of necessary material. Then, the problem of separation between construction sites and management offices are solved, and as a result, more efficient management of materials in construction sites will become possible.

• Science of Emotion and Sensibility
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• v.8 no.3
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• pp.221-229
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• 2005

This study aimed to understand the sex differences in cognitive behaviors in website design and demonstrate a practical basis for utilizing these differences into more user-centered design concept. Especially, we focused on the sex-different preference according to the information architecture of website navigation. First, We investigated general differences between men and women in cognitive behaviors through various literature studies. According to our investigation, men's cognitive works generally tend to follow a regular sequence and proceed step by step. On the other hand, women's cognitive style is generally characterized by random generation and simultaneous progress. To examine that these differences can be found in use of website navigation, we made an experiment in website design. We designed several test websites that have same contents but different style of navigation structure. A similar number of men and women were chosen for this test and they implemented given tasks. During the test, participants reported their preference on each websites and their implementing time and number of errors were collected. Based on the analysis of test data, it was possible to conclude that male participants' preference for the navigation with a narrow and deep information structure is relatively higher than female participants' preference for the same navigation, On the other hand, female participants have a preference of the navigation with a broad and swallow information structure. The result of study showed that there is a close correlation between the sex differences in preference of navigation types and the general sex differences in cognitive behavior. This finding can be used as a basis for designing the website navigation in which sex differences are reflected.

• Magazine of the Korea Concrete Institute
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• v.6 no.4
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• pp.113-122
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• 1994

To examine the applicabilty of the converter furnace slag from iron-works as concrete aggregate respective concrete furnace slag with contents of 20%. 40%, 60%. 80% were mixed with granulated slag, and the strength and stability tests for these specimens were followed. The slump value of the concrete mixed with converter furnace slag was higher than that of the conventional concrete. Furnace slag and granulated slag was increased as the increase of converter furnace content. The strength of the concrete mixed with converter furnace slag and granulate slag increased as an increase of converter furnace content and age. The expansion rate of the concrete mixed with converter furnace slag and granulated slag increased from 0.007% to 0.19% as the converter furnace content changed from 20% to 80%. From the above results in the strength and expansion rate, the concrete with the converter furnace content of 40% was considered to be recommandable for the stable construction of the concrete. Calculated formulas for tensile strength(${\sigma}_t$) and flexural strength(${\sigma}_f$) from the regression a.nalysis of the correlations among these compressive strength (${\sigma}_c$), tensile strength and flexural strength are as follows. ${\sigma}_t$ = 0.16952${\sigma}_c$ - 4.9313 ${\sigma}_f$ = 0.25727${\sigma}_c$ + 6.0528

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.5
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• pp.13-25
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• 2008

Although competitions for large parks are increasing rapidly across the world, theoretical research and critiques of these competitions are as yet insufficient. The 'International Design Competition for Central Open Space in Multi-functional Administrative City, Korea', a representative competition for large park design, can be a significant resource for examining the contemporary design strategies that go into the design of a large park. In this study, the authors make a framework for analysis by looking at the competition's design guidelines and literatures on 'large parks', and by then analyzing the ten finalists. Four questions that were derived from the framework were: 'what are the approaches to large parks?', 'what is the process of design?', 'what is the sustainability of the park?', and 'what are the relations between city and park?' The results of the study are as follows. First, the design concepts for large parks are primarily site-specific. It is particularly important in ensuring the identity of the large park. Second, it is difficult to find design proposals which satisfy the four main questions sufficiently, and works submitted tend to be visual-oriented, form-oriented, and results-centered. Third, the notion of 'sustainability' in large parks is a comprehensive one which includes various aspects such as ecology, finance, programming, and community. However, the notion remains ambiguous, and plans for operation and management are not concretely proposed. Finally, design proposals for large parks accompany positive relations with the city. Especially, 'productive parks' and 'city self-sufficiency' are very important demands in regards to large parks.

• Journal of the Korean Society for Library and Information Science
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• v.51 no.1
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• pp.175-199
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• 2017

Children's literature has a significant impact on children's intelligence and emotional development. The interest in children's literature is increasingly growing with the expectation of the award winning books and the educational values of children's books. Although the interest has brought about a quantitative increase in the domestic children's books, it has difficulty selecting high-quality children's books among various books. In such an environment, the Children's Literature Award will provide an authoritative source of choice, which will help guide the selection of quality books to those who want to read children's books. In addition to this trend, the library should check the status of winning works and incorporate them into new collection development policies. The purpose of this study is to present the direction of the library book development policy of the public library. For this purpose, 10 public libraries in Seoul, Korea were selected and analyzed quantitatively and qualitatively through the collection status of the children's literature winning books, loan status, turnover, Bonn's use Factor, and Trueswell's 80/20 rule. Based on the results of this analysis, we would like to suggest some issues to be reflected in library development policy of the future.

• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.2
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• pp.165-170
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• 2014

Shear horizontal (SH) waves propagate as a type of plate wave in a thin sheet. The dispersion characteristics of SH waves can be used for signal analysis. Therefore, SH-waves are useful for monitoring the structural health of a thin-sheet-structure. An electromagnetic acoustic transducer (EMAT), which is a non-contact ultrasonic transducer, can generate SH-waves easily by varying the shape and array of magnets and coils. Therefore, an EMAT can be applied to an automated ultrasonic testing system for structural health monitoring. When used as a sensor, however, the EMAT has a weakness in that electromagnetic interference (EMI) noise can occur easily in the automated system because of motors and electric devices. Alternatively, a fiber optic sensor works well in the same environment with EMI noise because it uses a light signal instead of an electric signal. In this paper, a fiber Fabry-P$\acute{e}$rot interferometer (FFPI) was proposed as a sensor to receive the SH-waves generated by an EMAT. A simple test was performed to verify the performance of the FFPI sensor. It is thus shown that the FFPI can receive SH-wave signals clearly.

• KIPS Transactions on Computer and Communication Systems
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• v.8 no.2
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• pp.41-56
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• 2019

Cloud manufacturing is a new concept of manufacturing process that works like a single factory with connected multiple factories. The cloud manufacturing system is a kind of large-scale CPS that produces products through the collaboration of distributed manufacturing facilities based on technologies such as cloud computing, IoT, and virtualization. It utilizes diverse and distributed facilities based on centralized information systems, which allows flexible composition user-centric and service-oriented large-scale systems. However, the cloud manufacturing system is composed of a large number of highly heterogeneous subsystems. It has difficulties in interconnection, data exchange, information processing, and system verification for system construction. In this paper, we derive the user requirements of various aspects of the cloud manufacturing system, such as functional, human, trustworthiness, timing, data and composition, based on the CPS Framework, which is the analysis methodology for CPS. Next, by analyzing the user requirements we define the system requirements including scalability, composability, interactivity, dependability, timing, interoperability and intelligence. We map the defined CPS system requirements to the requirements of oneM2M, which is the platform standard for IoT, so that the support of the system requirements at the level of the IoT platform is verified through Mobius, which is the implementation of oneM2M standard. Analyzing the verification result, finally, we propose a large-scale cloud manufacturing platform based on oneM2M that can meet the cloud manufacturing requirements to support the overall features of the Cloud Manufacturing CPS with dependability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.179-187
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• 2021

In the past five years, form construction, which accounts for approximately 25% of the total construction period, has continued to occur without a significant decrease in the number of deaths, with the largest proportion of collapse accidents. Accordingly, this study analyzed the difference in perception between the manager and worker by a questionnaire survey on the degree of risk and safety management level regarding a mold collapse accident. The survey was conducted in three groups: safety manager, field worker, and field manager. The results of the survey were analyzed by an independent sample T-Test using the SPSS program. As a result, there was almost no difference in recognition between managers, but a significant difference in recognition between managers and workers. In addition, there was a difference in management perception between the administrator and worker, which clearly shows the difference in the position between the administrator who manages and supervises hazardous disaster factors and the worker who works directly in the field. Such differences in perception can be a factor that cannot be mitigated. Based on this study, more developed research can narrow the perception gap between managers and workers and be used as a basic material for disaster research.

• Journal of Korea Water Resources Association
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• v.53 no.12
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• pp.1049-1057
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• 2020

This study aimed to develop a flow measurement method using drone in flood season. Measuring flow in all branches is difficult to conduct annually due to budget and labor limitation, safety and river works. Especially when heavy rain like storm comes, changes in stage-discharge relationship should be reviewed; however, it is usually impeded by the aforementioned issues. To solve the problem, it developed a simple measuring method with a minimum of labor and time. A numeric map and numeric orthophoto coordinate of South Korea are mostly based on Transverse Mercator Projection (TM) in accordance with rectangular coordinate system and use World Geodetic Reference System 1980 (GRS80) oval figure for conversion. Applying a concept of aerial photogrammetry, it located four visible Ground Control Points (GCP) near the river at Uijeongbu-si (Singok Bridge) and Yeongdong-gun (Youngdong 2nd Bridge) station and measured the coordinates using VRS DGPS. Hovering at a same level, drones took orthophoto of water surface at an interval of 3 seconds. It defined the pictures with GRS80 TM coordinate system, a rectangular coordinate system and then conducted an orthometric correction using GCP coordinates. According to X and Y coordinate analysis, it estimated the distance between the floating positions at 3 seconds-intervals and calculated the flow through the flow area according to the flow path. This study attested applicability of the flow measurement method using drone in flood season by applying the rectangular coordinate system based on the concept of aerial photogrammetry.

• Journal of Korea Water Resources Association
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• v.45 no.9
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• pp.853-860
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• 2012

It is well-known that loop effect of the stage-discharge relationship is formulated based on many field observations especially for the sand rivers. Theoretical understandings of the loop effect for the sand rivers have been widely provided, based on the facts that it is driven by the flood wave propagation and bed form changes over the given flood period. However, very few theoretical studies or field observations associated with loop-rating curves in the gravel or rock-bed mountain streams have been attempted so far, due particularly to the difficulties in the accurate discharge measurement during the flood in such field conditions. The present paper aims to report a unique loop-rating curve measured at a gravel and rock-bed mountain stream based on the flood discharge observation acquired during the typhoon, Muifa that passed nearby Jeju Island in summer of 2011. As velocity instrumentation, a non-intrusive Surface Velocity Doppler Radar to be suitable for the flood discharge measurement was utilized, and discharges were consecutively measured for every hour. Interestingly, the authors found that the hysteresis of the loop-rating curve was adverse compared to the typical trend of the sand bed streams, which means that the discharge of the rising limb is smaller than the falling limb at the same stage. We carefully speculate that the adverse trend of the loop-rating curve in the gravel bed was caused by the bed resistance change that works differently from the sand bed case.