A response spectrum method for seismic response analysis of structures under multi-support excitations

Jian-hua Li,Jie Li 국제구조공학회 2005 Structural Engineering and Mechanics, An Int'l Jou Vol.21 No.3

Study on mechanism of macro failure and micro fracture of local nearly horizontal stratum in super-large section and deep buried tunnel

Li, Shu-cai,Wang, Jian-hua,Chen, Wei-zhong,Li, Li-ping,Zhang, Qian-qing,He, Peng Techno-Press 2016 Geomechanics & engineering Vol.11 No.2

The stability of surrounding rock will be poor when the tunnel is excavated through nearly horizontal stratum. In this paper, the instability mechanism of local nearly horizontal stratum in super-large section and deep buried tunnel is revealed by the analysis of the macro failure and micro fracture. A structural model is proposed to explain the mechanics of surrounding rock collapse under the action of stress redistribution and shed light on the macroscopic analytical approach of the stability of surrounding rock. Then, some highly effective formulas applied in the tunnel engineering are developed according to the theory of mixed-mode micro fracture. And well-documented field case is made to demonstrate the effectiveness and accuracy of the proposed analytical methods of mixed-mode fracture. Meanwhile, in order to make the more accurate judgment about yield failure of rock mass, a series of comprehensive failure criteria are formed. In addition, the relationship between the nonlinear failure criterion and $K_I$ and $K_{II}$ of micro fracture is established to make the surrounding rock failure criterion more comprehensive and accurate. Further, the influence of the parameters related to the tension-shear mixed-mode fracture and compression-shear mixed-mode fracture on the propagation of rock crack is analyzed. Results show that ${\sigma}_3$ changes linearly with the change of ${\sigma}_1$. And the change rate is related to ${\beta}$, angle between the cracks and ${\sigma}_1$. The proposed simple analytical approach is economical and efficient, and suitable for the analysis of local nearly horizontal stratum in super-large section and deep buried tunnel.

Research on the motion characteristics of a trans-media vehicle when entering water obliquely at low speed

Li, Yong-li,Feng, Jin-fu,Hu, Jun-hua,Yang, Jian The Society of Naval Architects of Korea 2018 International Journal of Naval Architecture and Oc Vol.10 No.2

This paper proposes a single control strategy to solve the problem of trans-media vehicle difficult control. The proposed control strategy is just to control the vehicle's air navigation, but not to control the underwater navigation. The hydrodynamic model of a vehicle when entering water obliquely at low speed has been founded to analyze the motion characteristics. Two methods have been used to simulate the vehicle entering water in the same condition: numerical simulation method and theoretical model solving method. And the results of the two methods can validate the hydrodynamic model founded in this paper. The entering water motion in the conditions of different velocity, different angle, and different attack angle has been simulated by this hydrodynamic model and the simulation has been analyzed. And the change rule of the vehicle's gestures and position when entering water has been obtained by analysis. This entering water rule will guide the follow-up of a series of research, such as the underwater navigation, the exiting water process and so on.

An Acoustic Study on English Tense-Lax Vowel Pairs Produced by Chinese and Korean Speakers

Li, Jian Hua(이건화),Lee, Sook Hyang(이숙향) 원광대학교 인문학연구소 2017 열린정신 인문학연구 Vol.18 No.1

본 연구의 목적은 중국어화자와 한국어화자의 영어 긴장모음과 이완모음 산출의 스펙트럼 특성과 시간 특성의 화자집단 간 비교·분석이다. 피험자로 참여한 10명의 중국어모국어화자와 10명의 한국어모국어화자가 3쌍의 단어 heed/hid/-hid/hɪd/, had/hæd/-head/hɛd/, who’d/hud/-hood/hʊd/를 3번 반복으로 읽었다. 각 모음의 제1포만트(F1)와 제2포만트(F2) 및 지속시간을 측정하였다. 실험결과, 중국어화자는 주로 시간 특성에서 긴장모음과 이완모음을 구분한 반면 한국어화자는 주로 모음의 스펙트럼 특성에서 긴장모음과 이완모음을 구분하는 경향을 보였다. 스펙트럼 특성상 일부 단어쌍에서 중국어화자는 F1값에서만 긴장모음과 이완모음 간 차이를 보인 반면 한국어화자는 F1값과 F2값에서 차이를 보였다. /ʊ-u/ 단어쌍에서는 두 집단 모두 긴장모음과 이완모음 간 차이를 보이지 않았다. 시간 특성에서는 중국어화자는 세 단어쌍 모두에서 긴장모음과 이완모음의 지속시간 간 차이를 보였지만 한국어화자는 /i-ɪ/에서만 차이를 보였다. 두 집단이 영어의 긴장모음과 이완모음 대조에 스펙트럼 특성과 시간 특성을 동시에 이용하지 못하는 결과에 대한 한 가지 요인으로 L1의 부정적 간섭의 가능성을 논의했다. The purpose of this study is to compare the spectral and temporal characteristics of English tense and lax vowels produced by Chinese and Korean speakers. 10 Chinese and 10 Korean speakers served as subjects and read 3 pairs of words heed/hid/-hid/hɪd/, had/hæd/-head/hɛd/, who’d/hud/-hood/hʊd/ 3 times. The first two formants and vowel duration were measured. The results showed that Chinese speakers differentiated tense-lax vowel pairs mainly with temporal characteristics while Korean speakers mostly with spectral characteristics. With respect to spectral characteristics, Chinese speakers tended to differentiate tense from lax vowels in some pairs with the difference only in F1 while Korean speakers did with difference both in F1 and F2. Both Chinese and Korean speakers had difficulty in differentiating /u/ from /ʊ/. With respect to temporal characteristics, Chinese speakers differentiated the tense from lax vowels in all three vowel pairs while Korean speakers distinguished only in /i-ɪ/ but not in /æ-ɛ/ and /u-ʊ/ pairs. L1 negative transfer was suggested as one of the factors for the results that Chinese and Korean speakers did not use all the spectral and temporal features in tense vs. lax vowel contrast in English.

Expression, Purification, and Biological Characterization of The Amino-Terminal Fragment of Urokinase in Pichia pastoris

( Jian Ping Li ),( Yu Li Lin ),( Hong Qin Zhuang ),( Zi Chun Hua ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.9

Urokinase (uPA) and its receptor (uPAR) play an important role in tumor growth and metastasis. Targeting the excessive activation of this system as well as the proliferation of the tumor vascular endothelial cell would be expected to prevent tumor neovasculature and halt the tumor development. In this regard, the amino-terminal fragment (ATF) of urokinase has been confirmed as effective to inhibit the proliferation, migration, and invasiveness of cancer cells via interrupting the interaction of uPA and uPAR. Previous studies indicated that ATF expressed in Escherichia coli was mainly contained in inclusion bodies and also lacked posttranslational modifications. In this study, the biologically active and soluble ATF was cloned and expressed in Pichia pastoris. The recombinant protein was purified to be homogenous and confirmed to be biologically active. The yield of the active ATF was about 30 mg/l of the P. pastoris culture medium. The recombinant ATF (rATF) could efficiently inhibit angiogenesis, endothelial cell migration, and tumor cell invasion in vitro. Furthermore, it could inhibit in vivo xenograft tumor growth and prolong the survival of tumor-bearing mice significantly by competing with uPA for binding to cell surfaces. Therefore, P. pastoris is a highly efficient and cost-effective expression system for large-scale production of biologically active rATFs for potential therapeutic application.

Simplification Strategies Adopted by Chinese Adult and Child EFL Learners

Li, Jian-hua(이건화),Kang, Seok-keun(강석근) 원광대학교 인문학연구소 2017 열린정신 인문학연구 Vol.18 No.3

중국인 외국어 학습자는 영어의 자음군과 어말 자음을 습득할 때 모국어의 음소배열 제약으로 어려움을 겪을 수 있다. 본 연구는 중국 성인과 어린이들의 영어 어두와 어말 자음(군) 발화를 비교 연구함으로써 그들의 음운 패턴을 알아보기 위한 것이다. 본 연구는 주로 세 자음으로 구성된 자음군(CCC), 두 자음으로 구성된 자음군(CC)과 어말 자음(C)을 연구대상으로 하고 있으며, 이 자음군들이 포함된 30개 영어 단어를 각각 16명의 중국 성인 외국어 학습자와 16명의 중국 어린이 외국어 학습자들이 읽게 하고 비교한 것으로 그 결과는 다음과 같다. 성인과 어린이의 자음군 난이도순은 “CCC > CC > C”로 나타나고 있는데 음절초 자음군과 음절말 자음군에서 성인은 어린이보다 단순화 전략을 더 많이 사용하였다. 성인과 어린이들은 모두 생략보다 삽입을 더 많이 사용하였다. 어린이들은 음절초 자음군에서 삽입을 더 많이 선호한 반면, 성인은 음절말 자음 및 음절말 자음군에서 삽입을 더 많이 선호하였다. 성인과 어린이들은 음절말 자음 및 음절말 자음군보다 음절초 자음군에서 생략을 더 많이 선호하였다. 위의 결론은 모두 L1전이와 계발적 인자 그리고 유표성 이론으로 설명가능하다. Due to the phonotactic constraints, Chinese EFL learners may be expected to have difficulty in producing English consonant clusters and word-final single consonants. This paper attempts to make a comparative study of the English word-initial and word-final consonant clusters/consonants produced by Chinese children and adult learners and derive their phonological patterns. This study focused on the three-consonant clusters (CCC), two-consonant clusters (CC) and word-final consonants (C) in 30 words produced by 16 children and 16 adults. The results showed that difficulty rank in adults’ and children’s acquisition of consonant clusters was CCC > CC > C. Adults adopted more simplification strategies than children in onset and coda consonants. Both adults and children favored insertion more than deletion. Children tended to apply epenthesis in the onset consonant clusters, while adults were inclined to adopt epenthesis in coda consonant clusters. Adults and children adopted more deletion in onset than in coda. We claim that the results can be explained by L1 transfer, developmental factors and Markedness theories.

A response spectrum method for seismic response analysis of structures under multi-support excitations

Li, Jian-Hua,Li, Jie Techno-Press 2005 Structural Engineering and Mechanics, An Int'l Jou Vol.21 No.3

Based on the random vibration theory, a response spectrum method is developed for seismic response analysis of linear, multi-degree-of-freedom structures under multi-support excitations is developed. Various response quantities, including the mean and variance of the peak response, the response mean frequency, are obtained from proposed combination rules in terms of the mean response spectrum. This method makes it possible to apply the response spectrum to the seismic reliability analysis of structures subjected to multi-support excitations. Considering that the tedious numerical integration is required to compute the spectral parameters and correlation coefficients in above combination rules, this paper further offers simplified procedures for their computation, which enhance dramatically the computational efficiency of the suggested method. The proposed procedure is demonstrated for tow numerical examples: (1) two-span continuous beam; (2) two-tower cabled-stayed bridge by using Monte Carlo simulation (MC). For this purpose, this paper also presents an approach to simulation of ground motions, which can take into account both mean and variation properties of response spectrum. Computed results based on the response spectrum method are in good agreement with Monte Carlo simulation results. And compared with the MSRS method, a well-developed multi-support response spectrum method, the proposed method has an incomparable computational efficiency.

Separation Technology, Thermodynamics : Letters to The Editor ; Comments on Special Distillation Processes

( Jian Wei Li ),( Zhi Gang Lei ),( Cheng Yue Li ),( Biao Hua Chen ) 한국화학공학회 2005 Korean Journal of Chemical Engineering Vol.22 No.4

Enhancement of Pyruvate Production by Torulopsis glabrata through Supplement of Oxaloacetate as Carbon Source

Jian Chen,Li-Ming Liu,Guo-Cheng Du,Yin Li,Hua-Zhong Li 한국생물공학회 2005 Biotechnology and Bioprocess Engineering Vol.10 No.2

The capability of utilizing a TCA cycle intermediates as the sole carbon source by the multi-vitamin auxotrophic yeast Torulopsis glabrata CCTCC M202019 was demonstrated with plate count method. It is indicated that T. glabrata could grew on a medium with one of the TCA cycle intermediates as the sole carbon source, but more colonies were observed when glucose, acetate and one of the TCA cycle intermediates coexisted in the medium. Among the intermediates of the TCA cycle examined in this study, cell growth was improved by supplementing oxaloacetate. Further investigation showed that the presence of acetate was necessary when oxaloacetate was supplemented. By supplementing with 10 g/L of oxaloacetate in pyruvate batch fermentation, dry cell weight increased from 11.8 g/L to 13.6 g/L, and pyruvate productivity was enhanced from 0.96 gL-1h-1 to 1.19 gL-1h-1 after cultivation of 56 h. The yield of pyruvate to glucose was also improved from 0.63 g/g to 0.66 g/g. These results indicate that under vitamins limitation, the productivity and yield of pyruvate could be enhanced via an increase of cell growth by the supplementation of oxaloacetate.

Extracellular loop 3 (EL3) and EL3-proximal transmembrane helix 7 of the mammalian type I and type II gonadotropin-releasing hormone (GnRH) receptors determine differential ligand selectivity to GnRH-I and GnRH-II.

Li, Jian Hua,Choe, Han,Wang, Ai Fen,Maiti, Kaushik,Wang, Chengbing,Salam, Abdus,Chun, Sang Young,Lee, Won-Kyo,Kim, Kyungjin,Kwon, Hyuk Bang,Seong, Jae Young American Society for Pharmacology and Experimental 2005 Molecular pharmacology Vol.67 No.4

<P>Mammalian type I and II gonadotropin-releasing hormone (GnRH) receptors (GnRHRs) show differential ligand preference for GnRH-I and GnRH-II, respectively. Using a variety of chimeric receptors based on green monkey GnRHR-2 (gmGnRHR-2), a representative type II GnRHR, and rat GnRHR, a representative type I GnRHR, this study elucidated specific domains responsible for this ligand selectivity. A chimeric gmGnRHR-2 with the extracellular loop 3 (EL3) and EL3-proximal transmembrane helix 7 (TMH7) of rat GnRHR showed a great increase in ligand sensitivity to GnRH-I but not to GnRH-II. Point-mutation studies indicate that four amino acids, Leu/Phe(7.38), Leu/Phe(7.43), Ala/Pro(7.46), and Pro/Cys(7.47) in TMH7 are critical for ligand selectivity as well as receptor conformation. Furthermore, a combinatory mutation (Pro(7.31)-Pro(7.32)-Ser(7.33) motif to Ser-Glu-Pro in EL3 and Leu(7.38), Leu(7.43), Ala(7.46), and Pro(7.47) to those of rat GnRHR) in gmGnRH-2 exhibited an approximately 500-fold increased sensitivity to GnRH-I, indicating that these residues are critical for discriminating GnRH-II from GnRH-I. [Trp(7)]GnRH-I and [Trp(8)]GnRH-I but not [His(5)]GnRH-I exhibit a higher potency in activating wild-type gmGnRHR-2 than native GnRH-I, indicating that amino acids at positions 7 and 8 of GnRHs are more important than position 5 for differential recognition by type I and type II GnRHRs. As a whole, these data suggest a molecular coevolution of ligands and their receptors and facilitate the understanding of the molecular interaction between GnRHs and their cognate receptors.</P>