국내 레미콘사의 부순모래 사용실태 조사

김기훈,金虎林,金光華,윤기원,한천구 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

Crushed sand is made by crushing the rock artificially. With the wide shortage of natural fine aggregates at all regions in Korea. crushed sand has been increasingly consumed as a alternative aggreagtes of natural sand. But there is insufficient information related to the actual situation on the produce. quality and manufacturing company of crushed sand. In this paper. survey is performed in order to know actual consumption situation of crushed sand through ready mixed concrete company in domestic. The remicon companies using crushed sand were estimated with 55%. According to the using method of crushed sand. most remicon company used fine aggregates by mixing natural sand and crushed sand. It is found that natural sand is replaced by crushed sand by about 20~50%. For quality problems in using crushed sand. grain shape. grade and fine particles shall be improved to meet the quality requirement of remicon and wide application. Therefore. it is found that quality improvement of crushed sand is required.

Effect of shim configuration on internal die flows for non-Newtonian coating liquids in slot coating process

Guang-Lin Jin,안원기,김시조,남재욱,정현욱,현재천 한국유변학회 2016 Korea-Australia rheology journal Vol.28 No.2

In this study, a strategy for designing optimal shim configuration inside a slot die is suggested to assure the uniform coating flow distribution of various non-Newtonian shear-thinning liquids at the die exit in a slot coating system. Flow patterns of non-Newtonian liquids inside the slot die, via three-dimensional computations, have been compared using various shim geometries which can adjust the flow region in a slot manifold. The rather non-uniform (parabolic) velocity distributions of shear-thinning liquids at the die exit under the basic shim condition could be effectively flattened by the modification of shim geometry without the change of die manifold structure. Dimensions of hybrid shims for controlling flow features at edge and center regions within slit channel are positively tuned, according to the shear-thinning level of coating liquids.

Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Comparison Study Based on End Plate Subsidence and Cystic Change in Individuals Older and Younger than 65 Years

Lin, Guang-Xun,Quillo-Olvera, Javier,Jo, Hyun-Jin,Lee, Hyeong-Jin,Covarrubias-Rosas, Claudia Angelica,Jin, Chengzhen,Kim, Jin-Sung Elsevier 2017 World neurosurgery Vol.106 No.-

<P><B>Objective</B></P> <P>To compare the outcomes between patients older and younger than 65 years who underwent single-level minimally invasive transforaminal interbody fusion (MI-TLIF) surgery.</P> <P><B>Methods</B></P> <P>This study is a retrospective analysis of 76 patients who underwent MI-TLIF between April 2012 and June 2016. Group A consisted of 35 patients (<65 years) and group B consisted of 41 patients (≥65 years). Intraoperative data were recorded. The evaluation of clinical outcomes was based on the visual analog scale for back and leg pain and the Oswestry Disability Index. Radiologic outcomes including cage subsidence, end plate cyst formation, and fusion rate were assessed.</P> <P><B>Results</B></P> <P>The mean age of the study subjects was 65.3 years, and the mean duration of follow-up was 18.98 months. Group B had a higher rate of comorbidities compared with group A (90.24% vs. 57.14%, respectively; <I>P</I> < 0.05). There was no statistically significant difference in the rate of complications between the groups (group A, 14.29%; group B, 17.07%). Clinical outcomes significantly improved in both groups postoperatively (<I>P</I> < 0.05). Although bony fusion in group A was slightly higher than that in group B, the fusion rate was not statistically different according to age. There were no statistically significant differences in the rates of cage subsidence or positive cyst sign between the groups.</P> <P><B>Conclusions</B></P> <P>MI-TLIF presented similar safeness and acceptable outcomes and complication rate in both groups. Cyst formation may be aggravated by cage subsidence, because cage subsidence was a useful potential predictor of cyst formation.</P>

Comparing Outcomes of Banana-Shaped and Straight Cages in Transforaminal Lumbar Interbody Fusion for Lumbar Degenerative Diseases: A Systematic Review and Meta-Analysis

Guang-Xun Lin,Li-Ru He,Jin-Niang Nan,Wen-Bin Xu,Keyi Xiao,Zhiqiang Que,Shang-Wun Jhang,Chien-Min Chen,Ming-Tao Zhu,Gang Rui 대한척추신경외과학회 2024 Neurospine Vol.21 No.1

Objective: This meta-analysis aims to refine the understanding of the optimal choice between different cage shapes in transforaminal lumbar interbody fusion (TLIF) by systematically comparing perioperative data, radiological outcomes, clinical results, and complications associated with banana-shaped and straight bullet cages. Methods: A meticulous literature search encompassing PubMed, Embase, Scopus, Web of Science, China Knowledge Network, and Wanfang Data was executed up to October 5, 2023. Inclusion criteria focused on studies comparing banana-shaped and straight bullet cages in TLIF. The quality of included studies was assessed using appropriate tools such as the Newcastle-Ottawa Scale (NOS) for nonrandomized studies. Rigorous evaluations were performed for radiographic outcomes, including disc height (DH), segmental lordosis (SL), lumbar lordosis (LL), subsidence, and fusion rates. Clinical outcomes were meticulously evaluated using visual analogue scale (VAS), Oswestry Disability Index (ODI), and complications. Results: The analysis incorporated 7 studies, involving 573 patients (297 with banana-shaped cages, 276 with straight cages), all with NOS ratings exceeding 5 stars. No statistically significant differences were observed in operative time, blood loss, or hospitalization between the 2 cage shapes. Banana-shaped cages exhibited greater changes in DH (p = 0.001), SL (p = 0.02), and LL (p = 0.01). Despite statistically higher changes in ODI for straight cages (26.33, p < 0.0001), the actual value remained similar to banana-shaped cages (26.15). Both cage types demonstrated similar efficacy in VAS, complication rates, subsidence, and fusion rates. Conclusion: Although banana-shaped cages can excel in restoring DH, SL, and LL, straight bullet cages can provide comparable functional improvements, pain relief, and complication rates.

모넨신 첨가 수준이 반추위 미생물에 의한 발효성상, 메탄발생량 및 건물 분해율에 미치는 영향

Guang-Lin, Jin,지병주,Xiang-Zi, Li,Judder Shinekhuu,송만강 충북대학교 동물생명과학연구소 2008 동물생명과학연구 Vol.1 No.-

본 시험은 조사료와 농후사료의 비율 및 모넨신 첨가량이 반추위 미생물의 건물 분해율, 메탄 발생량 및 배양액의 발효성상에 미치는 영향을 평가하고자 in vitro 방법으로 실시되었다. 첨가사료의 조사료 및 농후사료의 비율은 각각 8:2, 5:5 및 2:8 로 하였으며, 모넨신의 첨가량은 0, 10, 30 및 50ppm/150ml의 수준으로 하였다. 배양액은 100ml의 반추위액과 50ml의 인공타액을 혼합하여 총 150ml로 배양하였다. 여기에 기질과 모넨신을 첨가하여 39℃에서 24시간동안 혐기적으로 배양하였다. 24시간 배양하였을 때, 건물 분해율은 농후사료 첨가수준이 증가됨에 따라 증가하였으나(P<0.001), 각 농후사료와 조사료의 첨가수준 내에서는 모넨신 첨가 및 첨가수준이 건물분해에는 영향하지 않았다. 배양 시작 3시간 후 부터 배양액 내의 pH는 농후사료 첨가수준이 증가함에 따라 뚜렷하게 낮아졌다 (P<0.001). 배양 6시간 경과하였을 때, 모넨신 첨가량이 증가됨에 따라 배양액의 pH는 증가되었다 (P<0.05). 총가스 발생량은 농후사료 첨가수준이 증가될수록 많아졌으며 (P<0.001), 이러한 현상은 전체배양기간 동안 동일하였다 (P<0.01). 메탄발생량은 총 가스 발생량과 비슷한 경향이었는데, 배양 후 9시간 경과하였을 때부터는 모넨신 첨가량이 많은 처리구에서의 메탄발생량이 현저하게 감소되었다 (P<0.01). An in vitro study was conducted to examine the effect of addition level of monensin on fermentation characteristics, methane production and dry matter degradability by mixed rumen microbes. Four levels(0ppm, 10ppm, 30ppm and 50ppm, w/v) of the monensin were added to the mixed solution of strained rumen fluid with artificial saliva(2:1, v/v) and 1,5g substrate (mixture of 80% concentrate and 20% forage) in nylon bag was placed in 150ml incubation solution, and incubated anaerobically for 24hours at 39℃. pH in incubation solution increased up to 1h incubation but decreased with incubation time thereafter for all the treatments. Ammonia-N concentration increased with time for all the treatments. However, pH and ammonia concentration were not influenced by added monensin levels. Total VFA concentration increased (P<0.01) with the decreasing monensin level at 3 and 6h incubations, although there was no significant difference between treatments at 24h incubations. The propionate proportion increased (P<0.05), but acetate and butyrate decreased (P<0.01) with monensin at 3 and 6h incubations. C₂2/C₃ ratio was decreased (P<0.05) by increasing the monensin levels at 3 and 6h incubations. The methane production decreased (P<0.05) as the monensin levels increased at 24h incubations. Dry matter degradation of the substrate was not affected by the monensin addition.

Finite-time Control for Discrete-Time Switched Systems with Time Delay

Lin-Lin Hou,Guang-Deng Zong,Yu-Qiang Wu 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.4

The problem of finite-time state feedback control is considered in this paper for a class of discrete-time switched systems with time delay. Firstly, the concepts of finite-time stability and finite-time boundedness are extended to discrete-time switched systems with time delay, respectively. Then, by re-sorting to the average dwell time approach and Lyapunov-Krasovskii functional technology, some new delay-dependent criteria guaranteeing finite-time boundedness and stability are developed. The state feedback controller is also obtained by virtue of a cone complement linearization (CCL) method. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed results.

An Unprecedented 3D Self-catenated Four-coordinated Dense Net of Silver-Organic Framework

Shu-Lin Xiao,Guang-hua Cui,Vladislav A. Blatov,Jian-Chen Geng,Guang-yue Li 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.6

Ischemic postconditioning protects cardiomyocytes against ischemia/reperfusion injury by inducing MIP2

Hong-Lin Zhu,Kang-Kai Wang,Xing Wei,Shun-Lin Qu,Chi Zhang,Xiao-Xia Zuo,Yan-Sheng Feng,Qi Luo,Guang-Wen Chen,Mei-Dong Liu,Lei Jiang,Xian-Zhong Xiao 생화학분자생물학회 2011 Experimental and molecular medicine Vol.43 No.8

Cardiomyocytes can resist ischemia/reperfusion (I/R)injury through ischemic postconditioning (IPoC)which is repetitive ischemia induced during the onset of reperfusion. Myocardial ischemic preconditioning up-regulated protein 2 (MIP2) is a member of the WD-40family proteins, we previously showed that MIP2 was up-regulated during ischemic preconditioning (IPC). As IPC and IPoC engaged similar molecular mechanisms in cardioprotection, this study aimed to elucidate whether MIP2 was up-regulated during IPoC and contributed to IPoC-mediated protection against I/R injury. The experiment was conducted on two models,an in vivo open chest rat coronary artery occlusion model and an in vitro model with H9c2 myogenic cells. In both models, 3 groups were constituted and randomly designated as the sham, I/R and IPoC/hypoxia postconditioning (HPoC) groups. In the IPoC group, after 45 min of ischemia, hearts were allowed three cycles of reperfusion/ischemia phases (each of 30 s duration)followed by reperfusion. In the HPoC group, after 6 h of hypoxia, H9c2 cells were subjected to three cycles of 10 minute reoxygenation and 10 minute hypoxia followed by reoxygenation. IPoC significantly reduced the infarct size, plasma level of Lactate dehydrogenase and creatine kinase MB in rats. 12 h after the reperfusion,MIP2 mRNA levels in the IPoC group were 10 folds that of the sham group and 1.4 folds that of the I/R group. Increased expression of MIP2 mRNA and attenuation of apoptosis were similarly observed in the HPoC group in the in vitro model. These effects were blunted by transfection with MIP2 siRNA in the H9c2cells. This study demonstrated that IPoC induced protection was associated with increased expression of MIP2. Both MIP2 overexpression and MIP2 suppression can influence the IPoC induced protection.

조사료 자원의 단백질 분획 및 Buffer 추출이 In Vitro 발효 성상, 분해율 및 Gas 생성량에 미치는 효과

김광림(Guang Lin Jin),Judder Shinekhuu,Wei-ze Qin,김종규(Jong Kyu Kim),주종관(Jong Kwan Ju),서성원(Seong-won Suh),송만강(Man Kang Song) 한국초지조사료학회 2012 한국초지조사료학회지 Vol.32 No.1

Buffer solubility and protein fractionation were evaluated from the hays (timothy, alfalfa and klein) and straws (tall fescue and rice), and in vitro trial was conducted to examine the effect of buffer extraction on fermentation characteristics, degradability and gas (CO₂ and CH₄) production. Buffer soluble protein (SP) content and A fraction in total protein were highest in alfalfa hay as 61% and 41.77%, respectively while lowest in rice straw (42.8% and 19.78%, respectively). No difference was observed in B1 fraction among forages but B2 fraction was slightly increased in klein hay (12.34%) and tall fescue straw (10.05%) compared with other forages (6.34~8.85%). B3 fraction of tall fescue was highest as 38.49% without difference among other forages while C fraction was highest in rice straw. pH in incubation solution was higher in all forages after extraction than before extraction at 3h (P<0.01) and 6h (P<0.05), and pH from hays of timothy and alfalfa was higher than the other forages at 6h (P<0.05) and 12h (P<0.001). Regardless of extraction, ammonia-N concentration from alfalfa hay was increased at all incubation times and extraction effect was appeared only at 3h incubation time (P<0.01). Total VFA concentration from alfalfa hay was highest up to 24h incubation while those from tall fescue straw and rice straw were lowest. Buffer extraction decreased (P<0.01~P<0.001) the total VFA concentration. Acetic acid proportion was increased (P<0.001) before extraction of forages but no difference was found between forages. Propionic acid(C3) proportion was also increased(P<0.001) before extraction in all forages than in straws at 3h, 24h and 48h incubations, and C₃ from hays were mostly higher (P<0.05) than from straws. Butyric acid proportion, however, was not affected by extraction at most incubation times. Parameter 'a' regarding to the dry matter (DM) degradation was increase (P<0.001) in all forages before extraction, and was decreased (P<0.05) in tall fescue straw and rice straw compared with hays. Parameter 'b' was also increased (P<0.001) before extraction but no difference was found between forages. Effective degradability of DM (EDDM) was higher (P<0.001) before extraction in most forages except for rice straw. Buffer extraction decreased (P<0.05) all parameters (a, b, and c) regrading to the crude protein (CP) degradation but no difference was found between forages. Effective degradation of CP (EDCP) was lower (P<0.05) in straws than in hays. Parameters 'a' and 'b' regarding to the NDF degradation (P<0.01) and effective degradability of NDF (EDNDF, P<0.001) were also higher in forages before extraction than after extraction but no difference was found between forages. Buffer extraction reduced (P<0.05~P<0.001) CO₂ production from all the forages uo to 24h incubation and its production was greater (P<0.05~P<0.01) from hays than straws. Methane (CH₄) production was also greater (P<0.01~P<0.001) in all forages at all incubation times, and its production was greater (P<0.05) from hays than from straws at most incubation times. Based on the results of the current study, it can be concluded that buffer solubility and CP fractionation might be closely related with in vitro VFA concentration, degradability and gas (CO₂ and CH₄) production. Thus, measurement of buffer solubility and protein fractionation of forages might be useful to improve TMR availability in the ruminants.

English Major's Imagined Communities, Investment, and EFL Learning at a Teachers’ University in China

Xu, Guang-lin,김정인 한국교원대학교 교육연구원 2022 敎員敎育 Vol.38 No.2

Purpose: This study aims to explore the relationship between three English major undergraduates’imaginations regarding their futures and their investment in English learning at a local teachers’university in China. The focal students learned English as a foreign language (EFL). Methods: Qualitative research was conducted during one academic semester from September toDecember 2020. The researchers followed two major courses, intensive reading and oral English. Datawere collected through classroom observations, semi-structured and open interviews, course documentsand students' artifacts. Data analysis was conducted with two levels of coding and the credibility wasensured with data triangulation. Results: Findings reveal that students’ imagined communities, with their imagined professional identitiesas the center, were historically constructed along personal English learning trajectories. Conclusion: The study revealed that these imagined communities informed their daily investmentin English learning at the university in terms of time, energy, and affection. Based on the data analysis,this study offers some pedagogical implications for more EFL learners and educators both at Chineseuniversities and beyond.