Coring Damage Extent of Rock Cores Retrieved from High In-situ Stress Condition: A Case Study

Peng Yan,Qi He,Wenbo Lu,Yanli He,Wei Zhou,Ming Chen 대한토목학회 2017 KSCE JOURNAL OF CIVIL ENGINEERING Vol.21 No.7

The distribution of damage in deep rock cores is critical for assessing its influence on rock mechanical characteristics. This paper presents a case study on estimating the coring damage extent induced by the stress redistribution through a combined method of numerical simulation and X-ray Computed Tomography (CT) scanning. Rock cores are taken at 1900 m depth from the test tunnel at Jin-ping Second Stage Hydropower Station (JPII) in China. Firstly, the stress path experienced by the rock core during coring has been examined by the numerical simulation, and the distribution of tensile zone in the cross-section of rock core is also discussed. Then two kinds of samples, collected from the same position under different stress levels, are scanned to obtain CT images, and a special CT value analysis strategy was adopted to evaluate coring damage intensities of these samples. The result indicates that the stress state can be regarded as the principal factor for the distribution of coring damage. During coring in the Test Tunnel of JPII under the quasi-hydrostatic stress condition, high tensile stresses (over 5 MPa) are observed at the exterior edge of rock cores, which may lead to the nucleation of microcracks around the core boundary, and the coring damage then propagates to the core centre. The CT scanning also illustrates that the coring damage zone may cover approximately 70~80% of the entire cross-section from the outside inside (stress level of 50 MPa), and that the central part of the core is less damaged or eventually undisturbed. Thus, intact rock samples can be expected to be obtained by overcoring the original rock cores. However, the applicability of the overcoring method seems to be largely dependent on the state of in-situ stress at the coring site. The whole core may be damaged if the lateral stress coefficient reaches a critical value (e.g. greater than 3.0), in which case a special coring equipment should be adopted to improve the stress state during coring.

Inhibition of Bone Resorption by Econazole in Rat Osteoclast-like Cells through Suppressing TRPV5

Peng Yan,Tang Li,Meng Bo,Liu Die,Liang Xing 대한약학회 2011 Archives of Pharmacal Research Vol.34 No.6

Osteoclasts are primary bone resorption cells and intervention in osteoclast activation is considered an effective therapeutic approach to treatment of bone diseases involving osteoclasts. TRPV5 was detected in osteoclasts and it has been thought to take part in the transportation of the degraded calcium in the resorption lacuna, which is essential for bone resorption. The aim of the present study was to examine the effects of a modulator of calcium dynamics, econazole, on the expression of TRPV5 and bone resorption activity in rat osteoclast-like cells (OLCs). OLCs were obtained by co-culturing rat bone marrow cells with osteoblasts and then culturing with different concentrations of econazole (0.01, 0.1, 1.0, 10.0 μmol/L). Cell counting and staining protocols were used to determine whether econazole influenced the survival of OLCs. Expression of TRPV5 in response to econazole treatment was assessed by western blotting. Bone resorption activity of OLCs was determined by measuring the resorption area of dentin slices with a microscope and a digital image analysis system. Additionally, Ca^2+ inside OLCs was tested. We found that econazole inhibited expression of TRPV5 in a dose dependent manner while it had no influence on the survival of OLCs and it therefore inhibited bone resorption activity in rat OLCs. Ca^2+ inside OLCs increased, suggesting a limited compensatory mechanism to make up for inhibition of TRPV5 effects.

Effect of stacking conditions on performance of a centrifugal pump

Peng Yan,Shiyang Li,Shuai Yang,Peng Wu,Dazhuan Wu 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.2

In this study, the effect of stacking condition of centrifugal pump impeller was investigated by Computational fluid dynamics (CFD). The performance curves of impellers with three different stacking conditions were compared. The Local Euler head distributions (LEH distribution) at blade Leading edge (LE) and Trailing edge (TE) were obtained to evaluate the contribution of different spanwise location to the total work. The positive stacking characterised by the hub leading the shroud was considered inappropriate in centrifugal pump impellers as it deteriorated the performance of the pump in whole flow rate range. The negative stacking characterised by the shroud leading the hub could improve flow stability and efficiency in low flow rates, it was manufactured and tested. The test results showed good agreement with CFD calculations. A hump zone was observed in zero stacking impeller between 0.9Q d and Q d . It was closely related to the drastic change in pattern of LEH distribution at the two flow rates. The internal flow was analyzed to reveal the reasons responsible for the hump in head curve. It is found that the tremendous extension of low streamwise velocity region and its instant movement from the corner of shroud and blade suction surface to the midspan near blade suction surface when the flow rate decreases from Q dto 0.9Q d is the main reason for flow instability in zero stacking impeller.

Development and Characterization of a highly-sensitive monoclonal antibody against thiacloprid

Pengyan LIU,Yuanhao GUO,Shasha JIAO,Ying Liu,Rubing ZOU,Ying Zhao,Yirong GUO,Guonian ZHU 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-

Spatial Analysis of Rural Medical Facilities Using Huff Model : A Case Study of Lankao County, Henan Province

Pengyan Zhang,,Xing Ren,Qianqian Zhang,Jianjian He,Yongmin Chen 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.1

Rural health care reformed in the new situation in China, indicating that the construction of medical facilities not only to solve difficult medical problems, but also to take into account the efficiency and fairness of the use of medical resources allocation. Facing these problems, the paper aims to assess the spatial distribution of rural medical services by using geographic information systems (GIS) and spatial accessibility indexes. Lankao County in Henan Province and 21 hospitals of township and county are selected as study samples. First adopted ArcGIS10.0 to collate data. Second, the authors established a network dataset to analysis the maximum coverage for hospital services space accessibility. At last, established Huff model and built a scientific evaluation for the current hospitals’ distribution. There are several findings from the case study. First, the distribution of medical facility is unbalanced in rural areas in term of per capita, such as opportunity for assessing medical services and the convenience of utilizing medical services. Second, by using the Huff Model to calculate the potential population in service regions, the Huff Model to calculate the potential population in service regions, the results showed the low efficiency of the use of medical resources and the problems in these regions.

An Analysis of Regional Economy and Resourcesand Environment Coordinated Development Based on PSR Model : A Case Study of Zhongyuan Urban Agglomerations

Pengyan Zhang,Jianjian He,Wang Huili,Zhimin Zhou 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.9

With the acceleration of urbanization, the resources and environment problem has become more and more prominent in Zhongyuan urban agglomerations. Based on evaluation model of resources and environment coordination degree of Pressure-State-Response (PSR), this study adopted the coordination degree analysis methods to calculate and evaluate the resources and environment coordinated development of nine central cities in Zhongyuan Urban Agglomerations from 2006 to 2013. Results showed that: (1) from 2006 to 2013, the statuses of the nine central cities in Zhongyuan Urban Agglomerations were in moderate coordination, elementary coordination, on the verge of imbalance and moderate imbalance, the economic development and the resources and environment statuses were not optimistic; (2) from 2006 to 2009, those cities’ statuses were in moderate imbalance, on the verge of imbalance and elementary coordination, the overall development coordination degree was not high, could not reach the state of coordinated development. Luoyang, Jiaozuo, Xuchang and Luohe’s coordinated development situation was not up to standard, whose status was in moderate imbalance; (3) from 2010 to 2013, the nine cities were on the verge of imbalance, elementary coordination and moderate coordination, coordinated development was improved.

성별 어휘 ‘男X/女X’에 대한 의미 연구

焦彭琰(Jiao Pengyan) 중국어문학연구회 2017 중국어문학논집 Vol.0 No.104

This article examined the lexical combination uses in actual language to search for semantic differences between gender words, ‘男人/女人’, ‘男性/女性’and ‘男子/女子’. It also noted that there is a difference in the degree of spatial variability between each gender words and that such spatial differences indicate the differences in referentiality in the discourse.

“X比Y<SUB>N</SUB>还W<SUB>N</SUB>”的句法、语义及语用特征小考

焦彭琰(Jiao, Pengyan) 한국중어중문학회 2019 中語中文學 Vol.- No.76

This paper investigates the syntactic, semantic and pragmatic features of the ‘X比YN还WN’ structure. We find that the ‘YN’ in ‘X比YN还WN’ uses a non-referential component to compare with X, and then expresses the characteristics of X on W. Moreover, because 还 has the characteristics of activating an expected sequence, the ‘YN’ must have highly identifiable characteristics and occupy an extreme position on the level of degree. The reduplication of nouns in this structure is to express more complex semantics, which accords with the cognitive motivation of quantitative iconicity.

漢韓表“穿戴義”動詞語義演變特徵小考 - 以“穿”和“입다”爲中心

焦彭琰(Jiao Pengyan) 중국어문학연구회 2019 중국어문학논집 Vol.0 No.119

This thesis uses the Chinese verb “穿” and the Korean verb “입다” as the research object, and analyzes the etymology and derivation of the two verbs in the two languages. Based on the etymology of the Chinese verb “穿”, we construct a “crossing” motion event-frame. And according to the etymology of the Korean verb “입다”, the motion event-frame of “coverage” is constructed. Due to the difference between the conceptual framework and the cognitive focus, the derived semantics are also very different.

현대 중국어 ‘別+VP+了+NP’ 구문 연구

焦彭琰(Jiao Pengyan),尹愛庚(Yoon, Ae-kyoung) 중국어문학연구회 2016 중국어문학논집 Vol.0 No.97

This paper explains the structure of ‘別+VP+了+NP’ in the modern Chinese. First we analysis the semantic feature of the ‘VP’ and semantic function of the ‘了’. By comparing with the structure of ‘別+VP+NP+了’, we can draw a meaning of the structure of ‘別+VP+了+NP’. And to conclude, the ‘VP’ in the structure of ‘別+VP+了+NP’ was restricted by the meaning of the structure of ‘別+VP+了+NP’. And more verbs can obtain the corresponding sentence semantics when they get into the structure of ‘別+VP+了+NP’.