• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.498-507
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• 2006

The main objective of present study was to evaluate how seasonal rainfall influenced natural habitat conditions of 10 metric habitat variables along with ionic conditions and suspended solids in the Woopo Wetland during August 2002-July 2003. Largest spatial variabilities in total suspended solids (TSS) occurred during the summer monsoon and the inorganic suspended solids (ISS), expressed as a inorganic proportion of total solids, showed linearly increasing trend from the upstream to downstream. This phenomenon was mainly attributed to counter flow of turbid water from the main Nakdong-River. During the flooding, ISS : TSS ratio showed large increases (92%) in the downstream than the upstream (43%). For this reason, transparency declined (mean=0.13 m, range=0.08-0.21 m) largely in the downstream reach and thus, chlorophyll-a concentration showed low values (range: $4.2-8.6\;{\mu}g\;L^{-1}$), indicating a direct influence on primary productivity or algal growth by inorganic turbidity. In the 2nd survey, ISS averaged 4.0 mg $L^{-1}$ (3.3-4.8 mg $L^{-1}$), thus the ISS decreased by 14 fold, compared to the ISS in the 1st survey during the flooding, while organic suspended solids (OSS) values were greater than those of ISS, indicating a dominance of organic solids. This condition was similar to solid contents in the 3rd survey, but showed a large difference compared to the 4th survey during the growing season. Habitat health assessments, based on 10 metric habitat variables, showed that QHEI values were greatest in the growing season (May) than any other seasons and largest spatial variations occurred in the 2nd survey. Overall, dataset suggest that seasonal episodic flooding during the monsoon may largely contribute nutrient cycling and sediment contents in the Woopo Wetland and Topyung Stream.

• Journal of KIISE:Software and Applications
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• v.37 no.7
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• pp.518-535
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• 2010

Cloud Computing is emerged as an effective reuse paradigm, where service providers operate hardware and software and as a service, and service consumers invoke the service through Internet. Software-as-a-Service (SaaS) is a type of cloud services, where the whole software is designed as a service so that several consumers can reuse the SaaS. While tradition software applications are developed for a specific organization, SaaS is developed for multiple users in the various organizations. Hence, reusability is very essential characteristic of SaaS. Reusability is defined as a metric of how effective and efficient software functionalities can be used by various users. Reusability in SaaS is evaluated by considering three sub-characteristics; applicability, adaptability, and scalability. Since such a SaaS has considerable differences and characteristics from traditional software applications, conventional methods including object-oriented modeling, component-based development method, and service-oriented architecture (SOA) service development method would be limited in developing services which can fulfill these three sub-characteristics related to reusability as well as SaaS-intrinsic characteristics. Hence, there is a great demand for effective processes for developing SaaS cloud services. In this paper, we present a practical process for developing SaaS, which focuses on ensuring reusability. And by performing a case study with our proposed SaaS development process, we evaluate applicability of our proposed process and explain how the process is used in a real domain. Then, we compare our proposed process with others for verifying our study. Through the proposed process, cloud services with high quality can be more effectively developed.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.5
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• pp.859-864
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• 2017

IoT is a new emerging technology to lead the $4^{th}$ industry renovation and has been widely used in industry and home to increase the quality of human being. In this paper, IoT based face detection and recognition system for a smart elevator is developed. Haar cascade classifier is used in a face detection system and a proposed PCA algorithm written in Python in the face recognition system is implemented to reduce the execution time and calculates the eigenfaces. SVM or Euclidean metric is used to recognize the faces detected in the face detection system. The proposed system runs on RaspberryPi 3. 200 sample images in ORL face database are used for training and 200 samples for testing. The simulation results show that the recognition rate is over 93% for PP+EU and over 96% for PP+SVM. The execution times of the proposed PCA and the conventional PCA are 0.11sec and 1.1sec respectively, so the proposed PCA is much faster than the conventional one. The proposed system can be suitable for an elevator monitoring system, real time home security system, etc.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.73-81
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• 2003

The construction industry has been experiencing a major challenge in its work force, 'the shortage of skilled craft workers.' This problem has been caused by several factors such as the poor image of the construction industry, lack of training and education, unclear career path, declining wages, and changing work force demographics. A 'step-change' approach called the 'Two-Tier Work Force Strategy' has been proposed by the Center for Construction Industry Studies (CCIS) to deal with the work force related issues in a radical way. It is composed of two separate strategies, Tier I and II. The Tier I strategy uses less skilled and task trained craft workers, and has a larger administrative site management team than the Tier II strategy. The Tier II strategy utilizes fewer, better-educated, and higher skilled workers who perform some lower-management functions in addition to craft functions. They are paid more, but produce more through higher skills, stay on the job longer through multi-skilling, and deliver improved project performance in safety, quality, schedule, and cost The Two-Tier Work Force Strategy has the potential to resolve the current work force problems and foster a better work force environment in the future.

• Korean Journal of Environment and Ecology
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• v.34 no.4
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• pp.282-293
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• 2020

This study investigated a long-term variation trend of water quality, fish compositions, and ecological health conditions in the Gwanpyeong stream located in the nearby Daejeon metropolitan city to understand the impact of urban development projects on the aquatic ecosystem. The sampling was made in four surveys (2009, 2010, 2016, 2019) before and after urbanization. The urban development was conducted in 2008, resulting in the stream's ecological disturbance, and the stream restoration was conducted in 2012. Thus, stream monitoring was conducted to analyze the ecological trends before and after the restoration. The multi-metric models for Fish Assessment Index(FAI) and necropsy-based Health Assessment Index(HAI) were applied in the fish community and organ-level, respectively, to assess the ecological health of the stream. Minimum turbidity and chlorophyll-a(Chl-a) occurred in the mid-stream(St. 2), and this was probably due to rapid current velocity in the riffle zone. We collected 18 fish species, and the dominant species was Zacco platypus (40.6%). In 2016 immediately after the stream restoration, the relative proportions of sensitive species and insectivore species were the highest along with highest values in the species diversity and species richness index, resulting in the best condition in the ecological health, based on FAI model values. However, the ecological health, based on the FAI, became worse in the latest survey conducted in 2019. The analysis of the HAI model based on the organ-level approach showed skin erosion in the fish of upper stream, kidney defects in downstream, and the liver and gill defects observed in all sites, indicating that the anatomical health was also affected.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.143-149
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• 2014

Currently, despite the quantitative growth of domestic journal, objective and metric criterion to evaluate the contents and quality of those journals is inadequate. As a result, depending on a foreign citation index like SCI to evaluate the research result is causing some problems such as, thesis of an excellent standard being presented and published in foreign countries, thus, neglecting journals written in Korean. Hereat, the Korea Citation Index(KCI) is constructing a database of the journals published by academic associations; scientific paper information, articles information, and bibliographic, analyzing the quoting relation. Consequently, KCI is providing the basic information and the corresponding quoting relations of journals and papers on its webpage. This study compares the impact level of domestic accounting related journals by KCI and analyzes the network among journals using the cross-citation frequency from a social network analysis point of view. As a result, Accounting-related journals are now more desirable than the location in order to have a variety of interdisciplinary research needs to be encouraged. Through this exchange of other disciplines and actively made, which is the phase of apparent accounting-related journals expect to be greatly enhanced looks.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.380-386
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• 2020

The mobile application market has grown over the past decade since the advent of smartphones, making it the largest market for electronic device software. As competition intensifies in the mobile application market, the impact of application evaluations on the consumption and usage patterns of users has also significantly increased. Therefore, research has been conducted on measures to evaluate mobile applications, but most of the research has relied on qualitative methods such as expert-centered interviews or surveys. In addition, evaluation measures are being constructed from the service provider's perspective, not from the service user's perspective. However, the possibility of application-specific analyses that minimize the subjectivity of researchers is growing, as large amounts of user review data enable quantitative analysis of actual users' assessment of applications. Therefore, this study presents a methodology that can complement current problems with existing quality assessments for mobile applications by utilizing user review data. To this end, the Topic Modeling technique LDA (Latent Dirichlet allocation) is applied in order to elucidate ways to improve existing evaluation measures from a user's perspective. The study is expected to reduce bias in service assessment due to the subjectivity of service providers and researchers as well as provide a measure of assessment by area of mobile applications from a consumer perspective.

• Tunnel and Underground Space
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• v.24 no.4
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• pp.255-274
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• 2014

The target of this study is large scale rock slope collapsed by around 7 pm on August, 2012, which is located at ${\bigcirc}{\bigcirc}$ limestone quarries of Gangneung city, Gangwondo. The slope prior to the collapse is formed as the height of about 200 m and the average inclination of $45^{\circ}$. The estimated amount of the collapse is about $1,500,000m^3$ with respect to the slope after the collapse. Geotechnical and field investigations such as boring, geophysical prospecting, surface geological survey, geological lineaments, borehole imaging, metric 3D imaging, experimental and field test, mining work by year, and daily rainfall were performed to find the cause of rock slope failure. Various analyzes using slope mass rating, stereonet projection, limit equilibrium method, continuum and non-continuum model were conducted to check of the stability of the slope. It is expected that the cause of slope failure from the results of various analysis and survey is due to the combined factors such as topography, rainfall, rock type and quality, discontinuities, geo-structural characteristics as the limestone cavity and fault zones, but the failure of slope in case of the analysis without the limestone cavity is not occurred. Safe factor of 0.66 was obtained from continuum analysis of the slope considering the limestone cavity, so the ultimate causes of slope failure is considered to be due to the influence of limestone cavity developed along fault zone.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.164-169
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• 1998

In order to evaluate the utility of the bituminous coal fly ash, gypsum, oyster shell as soil amendments, acid sandy loam soil with low boron content were amended in the upper 15cm with amendments, and then chinese cabbage was cultivated in fall. Amendments treated were, in metric tons per hectare, i ) none(Check) ; ii) 80 fly ash(FA) ; iii) 4shell(SH) ; iv) 56 fly ash+24gypsum (FG) ; v) 40 fiy ash + 24 gypsum +0.8 shell(FGS). On the whole, amendments imoroved soil chemical properties and contents of N, P, K, Ca, and B in leaves. Among treatmens, FA prominently neutralized soil pH and increased available $P_2O_5$ ,B but decreased Fe contents in soils. FGS also affected the increment of exchangeable Ca, Mg, and available B. Yield response in fresh weight of chinese cabbage was in order of 85% for FGS>77% for FG>66% FA>5% for SH plants. Reducing sugar and vitamin-C contents of leaves depending on treatments showed the same tendencies as that in yields, whereas crude fiber opposite to theme. In particular, FA, FG, and FGS plants showed normal growth without boron deficiency symotoms which appeared in Check and SH plants.Taken together, FGS was an effective combination enable to maximize the utility of fly ash, gypsum, and shell as soil amemdments, especially in cabbage yield and quality.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.65-69
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• 1998

In order to evaluate the utility of bituminous coal fly ash, gypsum, oyster shell as soil amendments, aadic clayloam paddy soils with low calaum content were amended in the upper 15㎝ with amendments, and then Chinese cabbage was cultivated under plastic film house. Amendments treated were, in metric tons per hectare, i) none(Check) ; ii) 80 fly ash(FA) ; iii) 4 shell(SH) ; iv) 56 fly ash+24 gypsum (FG) ; v) 40 fly ash+24 gypsum+0.8 shell(FGS). On the whole, soil chemical properties were improved by amendments treatments. Amongst treatments, FA prominently neutralized soil pH and increased contents of Av. $P_2O_5$, Ex. K, and Av. B in soils. Besides, it showed the highest ratio in bacteria/fungi and (bacteria+actinomycetes)/fungi. FGS also affected the neutralization of soil pH and the increment of Ex. Mg. Amendments plants appeared alkaline damages only at early growing stage, but showed positive responses in fresh weight yields : 23% for FGS : 21% for FG : 19 18% for SH. At harvesting, leaves both of FA and FGS plants had higher values in contents of N, P, K, Ca, Mg, Fe, Mn, Zn, B, reduang-sugar, and vitamin-C than of others. In especial, Check plants appeared the heart rot symptoms owing to calaum defiaency differently from amendments plants. Taken together, FGS was an effective combination enable to maximize the utility of fly ash, gypsum, shell as soil amendments, espeaally in cabbage yield and quality.