• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.1946-1952
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• 2005

New group 15 organometallic compounds, M$(phenanthrenyl)_3$ (M = P (1), Sb (2), Bi (3)) have been prepared from the reactions of 9-phenanthrenyllithium with $MCl_3$. A reaction of 9-(diphenylphosphino)phenanthrene with 2,6-diisopropylphenyl azide led to the formation of (phenanthrenyl)${(Ph)}_2P$=N-(2,6-$^iPr_2C_6H_3$) (4). The crystal structures of 2 and 4 have been determined by single-crystal X-ray diffractions, both of which crystallize with two independent molecules in the asymmetric unit. Compound 2 shows a trigonal pyramidal geometry around the Sb atom with three phenanthrenyl groups being located in a screw-like fashion with an approximately $C_3$ symmetry. A significant amount of CH- -$\pi$ interaction exists between two independent molecules of 4. The phosphorus center possesses a distorted tetrahedral environment with P-N bond lengths of 1.557(3)$\AA$ (P(1) N) and 1.532(3)$\AA$ (P(2)-N), respectively, which are short enough to support a double bond character. One of the most intriguing structural features of 4 is an unusually diminished bond angle of C-N-P, attributable to the hydrogen bonding of N(1)-H(5A) [ca. 2.49$\AA$ between two adjacent molecules in crystal packing. The compounds 1-3 show purple emission both in solution and as films at room temperature with emission maxima ($\lambda_{max}$) at 349, 366, and 386 nm, respectively, attributable to the ligand centered $\pi$ $\rightarrow$ $\pi^\ast$ transition in phenanthrene contributed by the lone pair electrons of the Gp 15 elements. Yet the nature of luminescence observed with 4 differs in that it originates from $\pi$ (diisopropylbenzene)-$\pi^\ast$ (phenanthrene) transitions with the $\rho\pi$contribution from the nitrogen atom. The emission maximum of 4 is red-shifted ranging 350-450 nm due to the internal charge transfer from the phenanthrenyl ring to the N-arylamine group as deduced from the ab initio calculations.

• Journal of the Korean Geotechnical Society
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• v.35 no.11
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• pp.97-110
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• 2019

Piles that support offshore wind turbine structures are dominantly subjected to cyclic lateral loads of wind, waves, and tidal forces. For a successful design, it is imperative to investigate the behavior of the cyclic laterally loaded piles; the p-y curve method, in which the pile and soil are characterized as an elastic beam and nonlinear springs, respectively, has been typically utilized. In this study, model pile tests were performed in a 1 g gravitational field so as to investigate the p-y behaviors of cyclic laterally loaded piles installed in saturated dense silty sand. Test results showed that cyclic lateral loads gradually reduced the overall stiffness of the p-y curves (initial stiffness and ultimate soil reaction). This is because the cyclic lateral loads disturbed the surrounding soil, which led to the decrement of the soil resistance. The decrement effects of the overall stiffness of the p-y curves became more apparent as the magnitude of cyclic lateral load increased and approached the soil surface. From the test results, the cyclic p-y curve was developed using a p-y backbone curve method. Pseudo-static analysis was also performed with the developed cyclic p-y curve, confirming that it was able to properly predict the behaviors of cyclic laterally loaded pile installed in saturated dense silty sand.

• Korean Journal of Health Education and Promotion
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• v.22 no.2
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• pp.195-213
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• 2005

Objectives: This study aims to determine fostering stress and mental health state that mothers of handicapped children perceive as primary care givers and to analyze their demand for information assistance in order to release their stress so that it can provide materials that contribute to establishment of assistance system for families with handicapped children. Methods: The research subjects were 340 mothers whose children went to a nursery for special children, 3 general nurseries and 6 special schools in Daegu, and the data were collected using structures questionnaires. The survey analyzed mothers' fostering stress, their demand for fostering information assistance, children's daily activity abilities. Component concepts of each scale was validated by adopting confirmatory factor analysis, and factors affecting demand for fostering information assistance were analyzed by adopting covariance structural analysis. Results: Younger mothers tend to have higher demand for information, and mothers with younger children or children with double handicaps also have higher demand. Mothers under 30 have the lowest demand for public health and medical care assistance and for home and community life assistance, while mothers with children with physical handicaps have the highest. The validity of component concepts was verified by categorizing as cognitive structure models fostering stress, information demand, children's daily activity abilities, and their appropriateness was evaluated through confirmatory factor analysis using structural equation modelling. And then, GFI (more than 0.9), CFI (more than 0.9), TLI (more than 0.9) and RMSAE (less than 0.08) were used to evaluate the appropriateness. It was found that all the component concepts are valid, as every item is within appropriate range. The result of analyzing information demand demonstrated that children's handicap levels significantly affect their mothers' mental health, while fostering stress significantly affect mothers' metal health, information demand. As well, it was confirmed that mothers' mental health has a significant effect on information demand. Conclusions: Therefore, to reduce special children's mothers' uncertainty, helplessness and fostering burden, it is necessary to provide them with information on children's challenges, development and fostering and to offer them quality public health, medical care and welfare assistance along with family and local community life assistance.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.388-395
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• 2015

Somatic embryogenesis is as an excellent technology for potential use in plant mass production, germplasm conservation, or genetic engineering. We examined the effect of cold storage using 3 embryogenic callus lines with different levels of embryogenesis competence derived from immature zygotic embryo cultures of Kalopanax setemlobus. Somatic embryo induction, germination and plant conversion were evaluated after 1, 3 and 6 months storage at $4^{\circ}C$ in the dark. Most cold-stored embryogenic calli formed somatic embryos normally even after 6 months; however, the induction rate was gradually decreased by increasing the storage period. The most competent line tended to show a slight decline in somatic embryo induction rate, as compared with other lines after cold storage. In general, cold storage resulted in reduced somatic embryo germination and plant regeneration, although 93% somatic embryo germination and 91% plant conversion were achieved regardless of the storage period. Cold storage led to cell browning and degradation. Additionally, the cell structures were confirmed by the aceto-carmine and evans blue dye evaluation. Collectively, our results showed that embryogenic callus of K. septemlobus could be preserved at $4^{\circ}C$ without subculture for 6 months, and suggested the need for storage of relatively more competent embryogenic calli lines to support somatic embryo induction.

• Tunnel and Underground Space
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• v.14 no.6 s.53
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• pp.440-449
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• 2004

Rock mass includes natural discontinuities such as joints and faults during its formation. Discontinuities are also referred as planes of weakness because of their weak mechanical characteristics. In the design of underground structures, it is necessary to consider the properties of discontinuities to insure the stability. During the excavation of a tunnel, these discontinuities have to be identified as early as possible so that proper change in excavation method or support design can be made accordingly. The excavation of the tunnel in a stable rock mass causes a 3-dimensional arching effect around the excavation face. It was revealed by previous studies that the existence of a weak zone or a fault zone ahead of tunnel foe induces a typical displacement tendency of convergence. For better understanding of the meaning of influence/trend lines of various displacement components, three-dimensional numerical analyses were conducted while varying deformation moduli, thicknesses and orientations of discontinuities. Numerical results showed that the changes in influence/trend lines of various displacement components were very similar to those by measurements. The discrepancies from the expected values were dependent on the physical properties, thicknesses and orientations of discontinuities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.309-316
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• 2020

This study analyzed Japan's three-dimensional road system as part of a study on urban regeneration plans through the three-dimensional use of road space. The three-dimensional road system integrates the Road Act, Urban Planning Act, and the Building Standard Act. The advantage of the three-dimensional road system is that landowners can freely use the space above and below the road so that they can live and operate sustainably, and road managers have the advantage of reducing the land acquisition costs because they only acquire rights to the road. In terms of type, it is applied to a variety of integrated and separated structures in elevated roads, underpasses, free passages, parking lots, and monorails. In addition, in the case of development methods, the degree of freedom of development plans is improved by enabling integrated maintenance of roads and buildings. Management stability is improved by applying management and law-based authority according to the Road Act. In this way, the three-dimensional road system provides support to maximize the use of limited available land through the three-dimensional use of road space, and to develop sustainable and good urban areas in development areas.

• Journal of KIISE:Computing Practices and Letters
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• v.6 no.3
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• pp.364-372
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• 2000

Subcategorization, defining dependency relation between predicates and their complements, is an important source of knowledge for resolving syntactic and semantic ambiguities arising in analyzing sentences. This paper describes a Korean subcategorization dictionary, particularly annotated with semantic roles of complements coupled with thesaural semantic hierarchy as well as syntactic dependencies. For annotating roles, we defined 25 semantic roles associated with surface case markers that can be used to derive semantic structures directly from syntactic ones. In addition, we used more than 120,000 entries of thesaurus to specify concept markers of noun complements, and also used 47 and 17 predicate patterns for verbs and adjectives, respectively, to express dependency relation between predicates and their complements. Using a full-fledged thesaurus for specifying concept markers makes it possible to build an effective selectional restriction mechanism coupled with the subcategorization dictionary, and using the standard predicate patterns for specifying dependency relations makes it possible to avoid inconsistency in the results and to reduce the costs for constructing the dictionary. On the bases of these, we built a Korean subcategorization dictionary for frequently used 13,000 predicates found in corpora with the aid of a tool specially designed to support this task. An experimental result shows that this dictionary can provide 72.7% of predicates in corpora with appropriate subcategorization information.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.2
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• pp.347-360
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• 2018

Due to the concentration and congestion of traffic in Seoul metropolitan area, effective utilization of underground space is required, and construction of various underground structures such as a double deck tunnel is increasing. Double deck tunnels are divided into upper and lower runways, and the most important part is middle slab. To investigate seismic behavior of middle slab, experimental study is required because of the complexity of the load and the mechanism of earthquake. In this study, centrifugal model tests were conducted to investigate the response characteristics of earthquake response according to the support conditions of the middle slab of a double deck tunnel. Artificial, Ofunato (short period) and Hachinohe (long period) seismic waves were employed in the experimental study. As a result, it was confirmed that the acceleration attenuation of elastomeric bearings condition was 10.6% in artificial earthquake, 13.6% in Ofunato earthquake, and 10.3% in Hachinohe earthquake. The results indicate that elastomeric bearings have some advantages in the viewpoint of seismic behaviors.

• Journal of the Korean Society for information Management
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• v.21 no.4 s.54
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• pp.109-131
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• 2004

As there are diverse delivery media and forms of information resources, their management schemes are diverse as well. In library community, cataloguing. rules for describing information resources such as AACR and KCR have been developed. The efforts to automate management of information resources based on these rules resulted in the development of MARC. However, MARC records are restricted in describing the information resources and MARC has various and distinct characteristics of the structural rigidity, which does not support the representation of extended semantic structures that exist among bibliographic entities. Therefore, since the data model for MARC is single-layer data model, it is not appropriate for describing information resources represented by multi-layer data model which can be used to set up the relationships among various objects in digital libraries. In this paper, we propose an a metadata model for digital libraries based on the IFLA FRBR basic model which supports multi-layer data model and a representation scheme based on XML Schema to manage the metadata about old books, old documents, resource related to music, conferences and seminars.

• Journal of Distribution Science
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• v.12 no.2
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• pp.17-25
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• 2014

Purpose - This study used empirical methods to investigate the consciousness structure of vendors in the S marketing area, which is a commercial revitalization district in the country, and examined its effect on their business activities. Based on the results derived through the performance of an actual proof analysis, this study aims to facilitate the promotion of changes in the consciousness structures of traditional market vendors, with a view to allowing them to adapt to the current economic realities in the country. Further, this study aims to provide suggestions that would improve the efficiency of the commercial revitalization program of the government. Research design, data, and methodology - This study examined all the stores in the S marketing area using a questionnaire survey conducted over three weeks beginning on July 4, 2012, and involved the performance of a data analysis on 1,859 samples. The questionnaire consisted of two parts. The first part addressed the market revitalization and the second part addressed the store management strategies. Questionnaire responses were calibrated based on a Likert scale. Statistical analysis was conducted using PASW version 18.0. Results - The results of the analysis of the consciousness structure of merchants in the S marketing area have led to the discovery that they have a medium level of satisfaction with market revitalization. There was a difference in the perceptions of the concept of store management between merchants and customers. Merchants have poor strategies for store management, which do not go much beyond an imitation of the practices of large domestic discount stores. Conclusions - The appearance of big discount stores and the accompanying changes in people's consumption patterns have led to a decline in local market areas. The government has sought new ways to secure autogenic power for local markets. To create regional economies, the government enacted a revised "Law for creating traditional markets and shopping streets" in 2010 and introduced a commercial district revitalization program. This program, which originally supported only the S marketing area, has subsequently expanded into neighboring shopping districts so that the whole of the regional market can be revitalized. However, since the revitalization of the traditional market and the government support required for it were mostly limited to facilities, the result has not proved to be effective. Although there are several reasons why the government investment was characterized by poor efficiency, traditional market vendors' consciousness structure, which did not adapt well to the vagaries of time and its consequent changes, was a major cause. Only when vendors have a true merchant spirit can they have a real service focus that will enable them to clearly understand the distribution organization. This will have the effect of bring about complete customer satisfaction and will ensure the survival and development of traditional markets.