• 연구윤리
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• 제1권2호
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• pp.11-13
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• 2020

Purpose: The author wants to specify scope of research, identify without giving burden, prevent unfair identification of the author, admit of production of the outcome, enact rules of identification, and build up foundation of development. Also, this study defines scope of publication of outcome of research to prevent unfair identification of authors and admit of them. Research design, data and methodology: The study described literary research, standard research, phenomenon research, and empirical result without methodologies, statistical analysis and scientific test and investigated operation system of KODISA cases. Results: At publication of findings of the research, researchers shall identify the ones of production of the finding to allocate help of the research. Conclusions: Scientific journals shall be controlled to develop ability and to grow up and have a system. Researchers shall give direction of other scientific journals. The study made efforts to be a model. KODISA Edition Team shall make an effort to keep and develop. So far, no regulation of identification of authors has produced disturbance so terminologies should be uniformed. Researchers shall keep rules of identification of authors to uniform and regulate identification of authors, conditions of authors, and order and correspondent authors. KODISA enacted rules of identification of authors for the first time in Korea to develop science.

• Structural Engineering and Mechanics
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• 제53권3호
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• pp.481-495
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• 2015

Many hydropower stations in southwest China are located in regions of brittle rock mass with high geo-stresses. Under these conditions deep fractured zones often occur in the sidewalls of the underground caverns of a power station. The theory and methods of fracture and damage mechanics are therefore adopted to study the phenomena. First a flexibility matrix is developed to describe initial geometric imperfections of a jointed rock mass. This model takes into account the area and orientation of the fractured surfaces of multiple joint sets, as well as spacing and density of joints. Using the assumption of the equivalent strain principle, a damage constitutive model is established based on the brittle fracture criterion. In addition the theory of fracture mechanics is applied to analyze the occurrence of secondary cracks during a cavern excavation. The failure criterion, for rock bridge coalescence and the damage evolution equation, has been derived and a new sub-program integrated into the FLAC-3D software. The model has then been applied to the stability analysis of an underground cavern group of a hydropower station in Sichuan province, China. The results of this method are compared with those obtained by using a conventional elasto-plastic model and splitting depth calculated by the splitting failure criterion proposed in a previous study. The results are also compared with the depth of the relaxation and fracture zone in the surrounding rock measured by field monitoring. The distribution of the splitting zone obtained both by the proposed model and by the field monitoring measurements are consistent to the validity of the theory developed herein.

• Journal of the Optical Society of Korea
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• 제20권6호
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• pp.716-721
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• 2016

A single-and dual-wavelength switchable polarized Yb-doped double-clad fiber laser around 1120 nm based on a pair of fiber Bragg gratings (FBGs) is demonstrated. The polarization-maintaining (PM) linear cavity is composed of a double clad PM Yb-doped fiber (YDF) and a pair of PM FBGs. The laser can operate in stable dual-wavelength or wavelength-switching modes due to the polarization hole burning (PHB) and the spatial hole burning (SHB) enhanced by the PM linear cavity. In dual-wavelength operation, the two orthogonally polarized wavelengths are centered at 1118.912 nm and 1119.152 nm, with an interval of 0.24 nm and a signal to noise ratio (SNR) of 35 dB. The maximum output power is 14.67 W when the launched LD pump is 24 W corresponding to an optical efficiency of 61.1%. The lasing lines switchover may be realized by adjusting the polarization controller (PC) fitted in the cavity. The two single-wavelengths are 1118.912 nm and 1119.152 nm. When the injected LD pump is 24 W, the highest output powers are 7.68 W and 8.64 W corresponding to optical efficiencies of 32% and 36% respectively. The spectral linewidth of the lasing lines are 0.075 nm and 0.07 nm, and the average numerical values of PER aredB and 19.9 dB, respectively.

• Geomechanics and Engineering
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• 제30권1호
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• pp.93-105
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• 2022

With the exploitation of natural resources in China, underground resource extraction and underground space development, as well as other engineering activities are increasing, resulting in the creation of many defective rocks. In this paper, uniaxial compression tests were performed on rocks with double holes and fractures at different angles using particle flow code (PFC2D) numerical simulations and laboratory experiments. The failure behavior and mechanical properties of rock samples with holes and fractures at different angles were analyzed. The failure modes of rock with defects at different angles were identified. The fracture propagation and stress evolution characteristics of rock with fractures at different angles were determined. The results reveal that compared to intact rocks, the peak stress, elastic modulus, peak strain, initiation stress, and damage stress of fractured rocks with different fracture angles around holes are lower. As the fracture angle increases, the gap in mechanical properties between the defective rock and the intact rock gradually decreased. In the force chain diagram, the compressive stress concentration range of the combined defect of cracks and holes starts to decrease, and the model is gradually destroyed as the tensile stress range gradually increases. When the peak stress is reached, the acoustic emission energy is highest and the rock undergoes brittle damage. Through a comparative study using laboratory tests, the results of laboratory real rocks and numerical simulation experiments were verified and the macroscopic failure characteristics of the real and simulated rocks were determined to be similar. This study can help us correctly understand the mechanical properties of rocks with defects and provide theoretical guidance for practical rock engineering.

• Geomechanics and Engineering
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• 제29권4호
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• pp.391-405
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• 2022

A newly proposed grouting simulation method, the sequential diffusion solidification method was introduced into the numerical simulation of combined bi-borehole grouting. The traditional, critical and difficult numerical problem for the temporal and spatial variation simulation of the slurry is solved. Thus, numerical simulation of grouting and blocking of flowing water in karst conduits is realized and the mechanism understanding of the combined bi-borehole technology is promoted. The sensitivity analysis of the influence factors of combined bi-borehole grouting was investigated. Through orthogonal experiment, the influences of proximal and distal slurry properties, the initial flow velocity of the conduit and the proximal and distal slurry injection rate on the blocking efficiency are compared. The velocity variation, pressure variation and slurry deposition phenomenon were monitored, and the flow field characteristics and slurry outflow behavior were analyzed. The interaction mechanism between the proximal and distal slurries in the combined bi-borehole grouting is revealed. The results show that, under the orthogonal experiment conditions, the slurry injection rate has the greatest impact on blocking. With a constant slurry injection rate, the blocking efficiency can be increased by more than 30% when using slurry with weak time-dependent viscosity behavior in the distal borehole and slurry with strong time-dependent viscosity behavior in the proximal borehole respectively. According to the results of numerical simulation, the grouting scheme of "intercept the flow from the proximal borehole by quick-setting slurry, and grout cement slurry from the distal borehole" is put forward and successfully applied to the water inflow treatment project of China Resources Cement (Pingnan) Limestone Mine.

• 유통과학연구
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• 제11권9호
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• pp.31-34
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• 2013

Purpose - This paper aims to explain that the Chinese distribution market will continue to bring tremendous business opportunities to commercial enterprises, given the relatively strong economic fundamentals and substantial government-led measures to boost domestic demand. Research design, data, methodology - A survey was conducted on China's retail market data during 2012. By empirically analyzing the data for retail sales of online markets and franchises, we conclude that the online retail market in China will continue to grow. Results - Based on data from 2012, 2013 is expected to be a challenging year for the retail sector, as both external and internal pressure is likely to persist. This paper outlines some major challenges facing retailers in China. Conclusions - The study shows that retailers in the Chinese market will face some major challenges: 1) the Chinese retail market is considerably affected by an uncertain economic outlook 2) an unfair environment of competition exists and 3) product safety is a serious issue. However, in the future, China's retail market will continue to bring tremendous business opportunities to commercial enterprises, given the relatively strong economic fundamentals and substantial government-led measures to boost domestic demand.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.401-405
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• 2006

A uniform velocity field of crust can be obtained by cumulative multi-year GPS data. Then the shortening and sliding of drape zones between Chinese Continent Blocks can be researched through the velocity field and dynamics meaning is also analyzed. A model of movement and strain is created to extract displacing and rotating information of blocks in this paper. On the basis of it, the shortening vectors and sliding states of drape zones between blocks can be obtained by the model of level center of gravity moving velocity vectors between neighboring blocks. Some result show as follows. India plate jostles greatly toward north, so a complicated movement situation is formed for 14 sub-blocks. And self-deformations of inner tectosomes can be greatly reflected according to the characteristics of drape zones between tectosomes. The extrusion deformation exists between Himalaya and Qiangtang blocks. Its contraction ratio is about 20.1 $mm.a^{-1}$. However, it only is $mm.a^{-1}$ between Tarim and Zhungar. The deformation characteristics and contraction ratio of other drape zones are obviously different with the former. The movement characteristics of contraction, shear, dislocation, etc. are showed in these zones. The average contraction ratio is about 5.0 $mm.a^{-1}$. The whole trend in the west continent has a big movement toward north, and in the east continent has a small movement toward south or southeast. The strain of west continent is far bigger than that of east, and the strain of southwest is bigger than that of the southeast. It is whole showed that India plate jostles toward north-east and the south-north zone has cutting and absorbing phenomena. The total characteristics and present-day trends of deformation of inland drape zones are basically described by the sinistrorse dislocation in south-north zone and Arjin fracture, the sinistrorse shear between south china and north china, etc.

• Asian-Australasian Journal of Animal Sciences
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• 제32권4호
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• pp.477-484
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• 2019

Objective: We aimed to observe hair follicle (HF) development in the dorsal skin and elucidate the expression patterns of genes and proteins related to skin and HF development in Rex rabbits from birth to 8 weeks of age. Methods: Whole-skin samples were obtained from the backs of Rex rabbits at 0, 2, 4, 6, and 8 weeks of age, the morphological development of primary and secondary HFs was observed, and the gene transcript levels of insulin-like growth factor-I (IGF-I), epidermal growth factor (EGF), bone morphogenetic protein 2 (BMP2), transforming growth factor ${\beta}-1$, 2, and 3 ($TGF{\beta}-1$, $TGF{\beta}-2$, and $TGF{\beta}-3$) were examined using quantitative real-time polymerase chain reaction (PCR). Additionally, Wnt family member 10b (Wnt10b) and ${\beta}$-Catenin gene and protein expression were examined by quantitative real-time PCR and western blot, respectively. Results: The results showed significant changes in the differentiation of primary and secondary HFs in Rex rabbits during their first 8 weeks of life. The IGF-I, EGF, $TGF{\beta}-2$, and $TGF{\beta}-3$ transcript levels in the rabbits were significantly lower at 2 weeks of age than at birth and gradually increased thereafter, while the BMP2 and $TGF{\beta}-1$ transcript levels at 2 weeks of age were significantly higher than those at birth and gradually decreased thereafter. ${\beta}$-Catenin gene expression was also significantly affected by age, while the Wnt10b transcript level was not. However, the Wnt10b and ${\beta}$-catenin protein expression levels were the lowest at 2 and 4 weeks of age. Conclusion: Our data showed that a series of changes in HFs in dorsal skin occurred during the first 8 weeks. Many genes, such as IGF-I, EGF, BMP2, $TGF{\beta}-1$, $TGF{\beta}-2$, $TGF{\beta}-3$, and ${\beta}$-Catenin, participated in this process, and the related proteins Wnt10b and ${\beta}$-Catenin in skin were also affected by age.

• 산경연구논집
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• 제7권1호
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• pp.15-17
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• 2016

Purpose - During the past twenty years, China has developed rapidly in economy. Meanwhile China's economic development has brought great many problems. Sustainable development is to achieve coordination in the ecological, economic and social aspects. Among them, the environment and resource issues are the most critical issues which affecting sustainable development in China. With China's rapid economic development, China's ecological environment is facing the most serious threat in water pollution, air pollution, solid waste pollution and the destruction of forests and biodiversity, resulting in a significant loss of the national economy. This research aims to examine whether the tragedy of the commons has hindered the sustainable development of China's economy or not. On the other hand, we try to analyze a solution to improve this situation. Research design, data, and methodology - Theoretical background study, finding optimization models, and data analysis. Results - In the case of a clear definition of property rights, the air will have a market price. The market price will coordinate pollutant emissions. Conclusions - The tragedy of commons has hindered the sustainable development. The model of China's Economic development should be changed.

• 유통과학연구
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• 제11권1호
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• pp.15-23
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• 2013

Purpose - During a reform period lasting 30 years, the Blue Economic Zone (BEZ) in the Shandong Peninsula has made progress in attracting foreign investment, and has acquired the foreign direct investment (FDI) essential for economic growth. It is therefore important to conduct a proactive and systematic study of FDI in the BEZ. Research design, data, methodology - This dissertation discusses the contribution of FDI on economic growth, from both a theoretical and empirical perspective. Taking seven core cities for study, statistics and econometrics are used, and panel data are used to validate FDI contribution to import and export in the BEZ. Results- FDI was found to exert both positive and negative influences on the imports and exports of the BEZ. In other words, the research findings are consistent with Trade Generated and Inverse Trade Generated theories put forward by Kojima and Mundell, among other researchers mentioned earlier in this paper. Further, FDI has greatly increased imports and exports for the BEZ. Conclusions - According to the results of this empirical study on local investment environment optimization, FDI plays an important role in foreign trade. This dissertation puts forward recommendations on using FDI to better promote economic growth in the BEZ.