• Journal of Korean Tunnelling and Underground Space Association
• /
• v.20 no.5
• /
• pp.855-867
• /
• 2018

When a weak zone exists ahead of tunnel face, the stress in the adjacent area would increase due to the longitudinal arching effect and the stability of the tunnel is affected. Therefore, it is critical to prepare a countermeasure through the investigation of the frontal weakness zone of the excavated face. Although there are several researches to predict the existence of weak zone ahead of tunnel face, such as geophysical exploration, numerical analysis and tunnel support, lack of studies on the relaxation zone depending on the width or distance from the vulnerable area. In this study, the impact of the weak zone on the formation of the relaxation zone was investigated. For this purpose, a series of laboratory test were carried out varying the width of the weak zone and the separation distance between tunnel face and weak zone. In the model test, sand with a water content of 3.8% was used to form a model ground. The model weak zone was constructed with dry sand curtains. The tunnel face was adjusted to allow a sequential excavation of upper and lower half part. load cells were installed on the bottom of the foundation and the tunnel face and measuring instruments for displacement were installed on the surface of the model ground to measure the vertical stress and surface displacements due to tunnel excavation respectively. The test results show that the width of weak zone did not affect the ground settlement while the ground subsidence drastically increased within 0.25D. The vertical stress and horizontal stress increased from 0.5D or less. In addition, the longitudinal arching effect is likely within the 1.0D zone ahead of the tunnel face, which may reduce the vertical stress in the ground following tunneling direction.

• Journal of Korean Society for Atmospheric Environment
• /
• v.10 no.E
• /
• pp.371-386
• /
• 1994

Ecological examinations of the radial growth Patterns of pine trees(Pinus densiflora Sieb. et Zucc) growing on Mt. Namsan in central Seoul were made to test a Proposition that the pine trees decline due to the influence of air pollution and acid rain, which was proposed by some researchers in Korea, and the potential effects of current level of air pollutants to the growth of the Pine trees in central Seoul have been speculated. Tree-rings of 40 trees sampled at 3 sites of Mt. Namsan were prepared and examined using a Computer-aided Tree-Ring Measuring System at Kookmin University, Korea. Air Pollutant data collected by the Ministry of Environment( MOE ) and the Forestry Research Institute(FRI) were used to infer the general conditions of the environment. Correlation analysis was applied to the data set of tree growth and the other environmental factors. General information derived from the close examination of the tree-rings and the data on air pollution, drought and the other biological conditions suggested that the growth of the pine trees was severely affected by the occurrence of drought(climatic variation), the prevalence of the pine leaf gall midges(insects), and the suppression by the black locust trees(Robinia pseudo-acacia L.) (competition among trees). While the current condition of air pollution in Seoul cannot be categorized as good, the concentrations of air pollutants are not so high as to cause acute damages to the trees. In addition, while the data of rain acidity showed episodic low PHs of under 4.0, the average of them is far less acidic than those which were observed in either northeastern United States or central Europe, where the decline of trees were not solely attributed to any of the air pollutants. Considering the sequential facts that one of the most important environmental factors that affect the growth of trees is weather condition of the forest that the proposition of the decline of the pine trees was made without careful examination of the growth patterns and past growth history of them as well as the complex influences of many other factors including the weather conditions to the growth of trees, and that no objective explanation has been made on the causal relationships between the current condition of air pollution and the growth of the trees, such a proposition should be evaluated as invalid for the explanation of tree growth on Mt. Namsan in central Seoul, Korea. The author evaluates the factors of air pollution (including acid rain) as the predisposing factors, which may have the Potentials to chronically affect the tree growth at the forest ecosystem on Mt. Namsan for a long period of time. Ecosystem ecological studies should be further carried out to carefully explain both the functional and the structural aspects of the ecosystem processes, which include the biogeochemistry and the long-term changes of soil conditions as well as the growth of the other tree species on the mountain.

• KSBB Journal
• /
• v.23 no.1
• /
• pp.90-95
• /
• 2008

In this study, a combined process of sequential anaerobic-aerobic digestion (SAAD), fluidized-bed bioreactor (FBBR), and ultrafiltration (UF) for the treatment of small scale food waste leachate was developed and evaluated. The SAAD process was tested for performance and stability by subjecting leachate from food waste to a two-phase anaerobic digestion. The main process used FBBR composed of aerators for oxygen supply and fluidization, three 5 ton reaction chambers containing an aerobic mesophilic microorganism immobilized in PE (polyethylene), and a sedimentation chamber. The HRTs (hydraulic retention time) of the combined SAAD-FBBR-UF process were 30, 7, and 1 day, and the operation temperature was set to the optimal one for microbial growth. The pilot process maintained its performance even when the CODcr of input leachate fluctuated largely. During the operation, average CODcr, TKN, TP, and salt of the effluent were 1,207mg/L, 100mg/L, 50 mg/L, and 0.01 %, which corresponded to the removal efficiencies of 99.4%, 98.6%, 89.6%, and 98.5%, respectively. These results show that the developed process is able to manage high concentration leachate from food waste and remove CODcr, TKN, TP, and salt effectively.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.29 no.3
• /
• pp.389-396
• /
• 2002

The purpose of this study was to compare the microtensile bonding strength of chemomechanically excavated dentin($Carisolv^{TM}$) to conventional caries removal(bur). The following adhesive systems were used; AB: All-Bond 2(3M, USA), PB: Prime & Bond 2.1(Dentsply, DE), AQ: AQ Bond(sun medical, Japan). 42 human molars with occlusal caries were assigned to 6 groups. Sequential caries removal was controlled with laser fluorescence. Each group was devided as follows; group A, B, C were $Carisolv^{TM}$ applied, group D,E,F were bur used. In group A and D, AB was used as a dentin adhesive. group B,E and group C,F was AQ and AQ was used each. The cavity was filled with composite resin(Z-100). The specimens were sectioned vertically into multiple serial 0.7 mm thick slabs. And then those slabs were sectioned into rectangular parts under 0.7 mm width. Finally 0.7-1.0 mm a right hexahedron shape stick become. Microtensile bonding test was carried out with testing apparatus at cross-head speed of $0.5\;mm/min^{-1}$ and fractured surfaces were observed with scanning electron microscope(JSM-6400, Jeol, Japan). The obtained results were summarized as follows ; 1. In the group of caries removal with $Carisolv^{TM}$, micro-tensile bonding strength decreased to $75.8{\sim}80$ percent of bur used group. 2. In the group of caries removal with $Carisolv^{TM}$, decreased degree of micro-tensile bonding strength is not so different in 3 kinds of dentin adhesives(p<0.05). 3. In the group of caries removal with $Carisolv^{TM}$, microtensile bonding strength of AB, PB, AQ was 32.6MPa(2.4), 30.1Mpa (1.8), 21.2Mpa(1.9). 4. In the group of caries removal with Bur and $Carisolv^{TM}$, microtensile bonding strength of AQ was significantly lower than that of AB and PB(p<0.01).

• Journal of Intelligence and Information Systems
• /
• v.18 no.2
• /
• pp.47-60
• /
• 2012

Video data comes in the form of the unstructured and the complex structure. As the importance of efficient management and retrieval for video data increases, studies on the video parsing based on the visual features contained in the video contents are researched to reconstruct video data as the meaningful structure. The early studies on video parsing are focused on splitting video data into shots, but detecting the shot boundary defined with the physical boundary does not cosider the semantic association of video data. Recently, studies on structuralizing video shots having the semantic association to the video scene defined with the semantic boundary by utilizing clustering methods are actively progressed. Previous studies on detecting the video scene try to detect video scenes by utilizing clustering algorithms based on the similarity measure between video shots mainly depended on color features. However, the correct identification of a video shot or scene and the detection of the gradual transitions such as dissolve, fade and wipe are difficult because color features of video data contain a noise and are abruptly changed due to the intervention of an unexpected object. In this paper, to solve these problems, we propose the Scene Detector by using Color histogram, corner Edge and Object color histogram (SDCEO) that clusters similar shots organizing same event based on visual features including the color histogram, the corner edge and the object color histogram to detect video scenes. The SDCEO is worthy of notice in a sense that it uses the edge feature with the color feature, and as a result, it effectively detects the gradual transitions as well as the abrupt transitions. The SDCEO consists of the Shot Bound Identifier and the Video Scene Detector. The Shot Bound Identifier is comprised of the Color Histogram Analysis step and the Corner Edge Analysis step. In the Color Histogram Analysis step, SDCEO uses the color histogram feature to organizing shot boundaries. The color histogram, recording the percentage of each quantized color among all pixels in a frame, are chosen for their good performance, as also reported in other work of content-based image and video analysis. To organize shot boundaries, SDCEO joins associated sequential frames into shot boundaries by measuring the similarity of the color histogram between frames. In the Corner Edge Analysis step, SDCEO identifies the final shot boundaries by using the corner edge feature. SDCEO detect associated shot boundaries comparing the corner edge feature between the last frame of previous shot boundary and the first frame of next shot boundary. In the Key-frame Extraction step, SDCEO compares each frame with all frames and measures the similarity by using histogram euclidean distance, and then select the frame the most similar with all frames contained in same shot boundary as the key-frame. Video Scene Detector clusters associated shots organizing same event by utilizing the hierarchical agglomerative clustering method based on the visual features including the color histogram and the object color histogram. After detecting video scenes, SDCEO organizes final video scene by repetitive clustering until the simiarity distance between shot boundaries less than the threshold h. In this paper, we construct the prototype of SDCEO and experiments are carried out with the baseline data that are manually constructed, and the experimental results that the precision of shot boundary detection is 93.3% and the precision of video scene detection is 83.3% are satisfactory.

• Journal of Internet Computing and Services
• /
• v.20 no.4
• /
• pp.63-72
• /
• 2019

As a sub-concept of corporate or organization governance, business governance and IT governance have become major research topics in academia. However, despite the importance of process as a construct for mediating the domain between business and information technology, research on process governance is relatively inadequate. Process Governance focuses on activities that link business strategy with IT system implementation and explains the creation of corporate core values. The researcher studied the basic conceptual governance models of political science, sociology, public administration, and classified governance styles into six categories. The researcher focused on the series of metamodels. For examples, the traditional Strategy Alignment Model(SAM) by Henderson and Venkatraman which is replaced by the neo-SAM model, organizational governance network model, sequential organization governance model, organization governance meta model, process governance CUBE model, COSO and process governance CUBE comparison model, and finally Process Governance Framework and etc. The Major difference between SAM and neo-SAM model is Process Governance domain inserted between Business Governance and IT Governance. Among several metamodels, Process Governance framework, the core conceptual model consists of four activity dimensions: strategic aligning, human empowering, competency enhancing, and autonomous organizing. The researcher designed five variables for each activity dimensions, totally twenty variables. Besides four activity dimensions, there are six driving forces for Process Governance cycle: De-normalizing power, micro-power, vitalizing power, self-organizing power, normalizing power and sense-making. With four activity dimensions and six driving powers, an organization can maintain the flexibility of process governance cycle to cope with internal and external environmental changes. This study aims to propose the Process Governance competency model and Process Governance variables. The situation of the industry is changing from the function-oriented organization management to the process-oriented perspective. Process Governance framework proposed by the researcher will be the contextual reference models for the further diffusion of the research on Process Governance domain and the operational definition for the development of Process Governance measurement tools in detail.

• 기호학연구
• /
• no.54
• /
• pp.119-145
• /
• 2018

This paper attempts to divide the narrative into three levels and review the approach methodology to understand Princess Bari as a narrative. If the stratification of the narrative, the analysis of each levels, and the integrated approach to them are made, this can contribute to suggesting new directions and ways to understand and study Princess Bari. The story level of Princess Bari, the surface structure, is shaped by the space movement and the chronological sequential structure of the life task that started from the birth of the main character. This story shows how a woman who was denied her existence by her father as soon as she was born finds an ontological transformation and identities through a process. Especially, the journey of finding identity is mainly formed through the events that occur through the relationship with family members. This structure, which can be found in the narrative level, forms a deep structure with the oppositional paradigm of family members' conflict and reconciliation, life and death. The thought structure revealed in this story is the problem of life is the problem of family composition, and the problem of death is also the same. In response to how to look at the unified world of coexistence of life and death, this tradition group of myths makes a relationship with man and God. This story is mainly communicated in the Korean shamanistic ritual(Gut) that sent the dead to the afterlife. Although the shaman is the sender and the participants in the ritual are the receivers, the story is well known a message that does not have new information repeated in certain situations. In gut, the patrons and participants do not simply accept the narrative as a message, but accept themselves as codes for reconstructing their lives and behavior through autocommunication. By accepting the characters and events of as a homeomorphism relationship with their lives, people accept the everyday life as an integrated view of life and death, disjunction and communication, conflict and reconciliation, and the present viewpoint. It can not change the real world, but it changes the attitude of 'I' about life. And it is a change and transformation that can be achieved through personal communication like the transformation of Princess Bari into god in myth. Thus, Princess Bari shows that each meaning and function in the story level, composition level, and communication level is related to each other. In addition, the structure revealed by this narrative on three levels is also effective in revealing the collective consciousness and cultural system of the transmission group.

• Korean Journal of Environment and Ecology
• /
• v.35 no.3
• /
• pp.223-236
• /
• 2021

This study aims to provide basic data for the systematic conservation and efficient management of forest ecosystems by analyzing changes in understory vegetation of temperate broad-leaved deciduous forests. One-hectare permanent survey plot, consisting of 100 subplots sized 10 × 10 meters, was installed in Gwangneung forest in Pocheon, Gyeonggi-do in 2003. The state of stands and the understory vegetation in the permanent survey plot were examined at a 5-year interval from 2003 to 2018. The vascular plants found in the survey area were 56 families, 128 genera, 176 species, 18 variants, 4 varieties, and 1 subspecies, for a total of 199 taxa. The number of species in both the shrub layer and the herbaceous layer showed a tendency to decrease with time. The MRPP-tests showed a significantly differing species composition of the shrub layer in all years except 2008-2013, whereas significant differences were found in all years concerning the herbaceous layer. As for the average importance value, Euonymus oxyphyllus (18.23%), Acer pseudosieboldianum (16.48%), and Callicarpa japonica (13.85%) were dominant in the shrub layer, while Ainsliaea acerifolia (23.41%), Disporum smilacinum (9.45%), and Oplismenus undulatifolius (5.62%) were dominant in the herbaceous layer. In the shrub layer, the richness of Smilax china, Lonicera subsessilis, and Philadelphus schrenkii was high when the basal area and the stand density of an upper layer were high. By contrast, smaller basal area and stand density were associated with the richness of Acer pseudosieboldianum, Deutzia glabrata, Morus bombycis, and Cornus kousa. Furthermore, it was found out that the impact of the basal area and the stand density on the herbaceous layer decreased over time, while the herb layer's species composition was greatly affected by cover degrees of Euonymus oxyphyllus and Acer pseudosieboldianum in the shrub layer. In conclusion, the number of species in the understory vegetation in Gwangneung forest is continuously decreasing, thus implying that species diversity, basal area, and stand density of an upper layer can influence the species composition in understory vegetation.

• Journal of Intelligence and Information Systems
• /
• v.27 no.4
• /
• pp.49-71
• /
• 2021

Users who intend to utilize knowledge to actively solve given problems proceed their jobs with cross- and sequential exploration of associated knowledge related each other in terms of certain criteria, such as content relevance. A knowledge map is the diagram or taxonomy overviewing status of currently managed knowledge in a knowledge-base, and supports users' knowledge exploration based on certain relationships between knowledge. A knowledge map, therefore, must be expressed in a networked form by linking related knowledge based on certain types of relationships, and should be implemented by deploying proper technologies or tools specialized in defining and inferring them. To meet this end, this study suggests a methodology for developing the knowledge graph-based knowledge map using the Graph DB known to exhibit proper functionality in expressing and inferring relationships between entities and their relationships stored in a knowledge-base. Procedures of the proposed methodology are modeling graph data, creating nodes, properties, relationships, and composing knowledge networks by combining identified links between knowledge. Among various Graph DBs, the Neo4j is used in this study for its high credibility and applicability through wide and various application cases. To examine the validity of the proposed methodology, a knowledge graph-based knowledge map is implemented deploying the Graph DB, and a performance comparison test is performed, by applying previous research's data to check whether this study's knowledge map can yield the same level of performance as the previous one did. Previous research's case is concerned with building a process-based knowledge map using the ontology technology, which identifies links between related knowledge based on the sequences of tasks producing or being activated by knowledge. In other words, since a task not only is activated by knowledge as an input but also produces knowledge as an output, input and output knowledge are linked as a flow by the task. Also since a business process is composed of affiliated tasks to fulfill the purpose of the process, the knowledge networks within a business process can be concluded by the sequences of the tasks composing the process. Therefore, using the Neo4j, considered process, task, and knowledge as well as the relationships among them are defined as nodes and relationships so that knowledge links can be identified based on the sequences of tasks. The resultant knowledge network by aggregating identified knowledge links is the knowledge map equipping functionality as a knowledge graph, and therefore its performance needs to be tested whether it meets the level of previous research's validation results. The performance test examines two aspects, the correctness of knowledge links and the possibility of inferring new types of knowledge: the former is examined using 7 questions, and the latter is checked by extracting two new-typed knowledge. As a result, the knowledge map constructed through the proposed methodology has showed the same level of performance as the previous one, and processed knowledge definition as well as knowledge relationship inference in a more efficient manner. Furthermore, comparing to the previous research's ontology-based approach, this study's Graph DB-based approach has also showed more beneficial functionality in intensively managing only the knowledge of interest, dynamically defining knowledge and relationships by reflecting various meanings from situations to purposes, agilely inferring knowledge and relationships through Cypher-based query, and easily creating a new relationship by aggregating existing ones, etc. This study's artifacts can be applied to implement the user-friendly function of knowledge exploration reflecting user's cognitive process toward associated knowledge, and can further underpin the development of an intelligent knowledge-base expanding autonomously through the discovery of new knowledge and their relationships by inference. This study, moreover than these, has an instant effect on implementing the networked knowledge map essential to satisfying contemporary users eagerly excavating the way to find proper knowledge to use.

• Journal of Intelligence and Information Systems
• /
• v.28 no.2
• /
• pp.127-146
• /
• 2022

Recently, as word embedding has shown excellent performance in various tasks of deep learning-based natural language processing, researches on the advancement and application of word, sentence, and document embedding are being actively conducted. Among them, cross-language transfer, which enables semantic exchange between different languages, is growing simultaneously with the development of embedding models. Academia's interests in vector alignment are growing with the expectation that it can be applied to various embedding-based analysis. In particular, vector alignment is expected to be applied to mapping between specialized domains and generalized domains. In other words, it is expected that it will be possible to map the vocabulary of specialized fields such as R&D, medicine, and law into the space of the pre-trained language model learned with huge volume of general-purpose documents, or provide a clue for mapping vocabulary between mutually different specialized fields. However, since linear-based vector alignment which has been mainly studied in academia basically assumes statistical linearity, it tends to simplify the vector space. This essentially assumes that different types of vector spaces are geometrically similar, which yields a limitation that it causes inevitable distortion in the alignment process. To overcome this limitation, we propose a deep learning-based vector alignment methodology that effectively learns the nonlinearity of data. The proposed methodology consists of sequential learning of a skip-connected autoencoder and a regression model to align the specialized word embedding expressed in each space to the general embedding space. Finally, through the inference of the two trained models, the specialized vocabulary can be aligned in the general space. To verify the performance of the proposed methodology, an experiment was performed on a total of 77,578 documents in the field of 'health care' among national R&D tasks performed from 2011 to 2020. As a result, it was confirmed that the proposed methodology showed superior performance in terms of cosine similarity compared to the existing linear vector alignment.