습식 볼밀 분쇄에서의 내부 분급 효과에 관한 연구

김정윤,조희찬,( L. G. Austin1 ) 한국화학공학회 2007 화학공학의이론과응용 Vol.10 No.1

일반적으로 제품 생산에 활용되는 습식 볼밀 운전 조건 하에서는 굵은 입자들이 1차 분쇄 모델에 의해 예상되는 것보다 적게 배출되는 내부 분급 현상이 나타난다. 이러한 현상을 이해하기 위해서 4가지 방법의 보정 방법을 적용하여 보았다. 첫째는 밀 배출구에 가상의 분급 장치의 존재를 가정하는 것이고, 두 번째는 입도별로 다른 체류 시간을 가정하는 것이다. 셋째는 분쇄율(Specific rates of breakage) 공식을 수정하여 시간에 따라 분쇄율이 변한다고 가정하는 것이고, 넷째는 1차 분쇄 모델이 아닌 비 1차 분쇄 모델(non-first order breakage kinetics)을 도입하는 것이다. 네 가지 방식에 대해 문헌에 제시된 분쇄 실험 결과를 활용하여 적용 작업을 수행하였으며, 넷째 방법을 제외한 다른 방법들은 보정 작업이 간단한 반면 분쇄가 진행됨에 따라 각 방법들에 적용되는 변수값들의 변화폭이 크게 나타났다. 반면 넷째 방법에서는 보정 작업은 복잡하지만 변수값들의 변화가 작았다. 이는 내부 분급 현상이 비 1차 반응에 의해 주로 발생한다는 것을 의미한다고 하겠다.

Insitu Assessment of Soil Nitrate-Nitrogen in the Pigeon Pea-Groundnut Intercropping-Maize Rotation System: Implications on Nitrogen Management for Increased Maize Productivity

Austin Tenthani Phiri,George Yobe Kanyama-Phiri,Ray Weil,John Msaky,Julie Grossman,Austin Tenthani Phiri 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Outcomes and physiologic responses associated with ketamine administration after traumatic brain injury in the United States and Canada: a retrospective analysis

( Austin J. Peters ),( Saad A. Khan ),( Seiji Koike ),( Susan Rowell ),( Martin Schreiber ) 대한외상학회 2023 大韓外傷學會誌 Vol.36 No.4

Purpose: Ketamine has historically been contraindicated in traumatic brain injury (TBI) due to concern for raising intracranial pressure. However, it is increasingly being used in TBI due to the favorable respiratory and hemodynamic properties. To date, no studies have evaluated whether ketamine administered in subjects with TBI is associated with patient survival or disability. Methods: We performed a retrospective analysis of data from the multicenter Prehospital Tranexamic Acid Use for Traumatic Brain Injury trial, comparing ketamine-exposed and ketamine-unexposed TBI subjects to determine whether an association exists between ketamine administration and mortality, as well as secondary outcome measures. Results: We analyzed 841 eligible subjects from the original study, of which 131 (15.5%) received ketamine. Ketamine-exposed subjects were younger (37.3±16.9 years vs. 42.0±18.6 years, P=0.037), had a worse initial Glasgow Coma Scale score (7±3 vs. 8±4, P=0.003), and were more likely to be intubated than ketamine-unexposed subjects (88.5% vs. 44.2%, P<0.001). Overall, there was no difference in mortality (12.2% vs. 15.5%, P=0.391) or disability measures between groups. Ketamine-exposed subjects had significantly fewer instances of elevated intracranial pressure (ICP) compared to ketamine-unexposed subjects (56.3% vs. 82.3%, P=0.048). In the very rare outcomes of cardiac events and seizure activity, seizure activity was statistically more likely in ketamine-exposed subjects (3.1% vs. 1.0%, P=0.010). In the intracranial hemorrhage subgroup, cardiac events were more likely in ketamine-exposed subjects (2.3% vs. 0.2%, P=0.025). Ketamine exposure was associated with a smaller increase in TBI protein biomarker concentrations. Conclusions: Ketamine administration was not associated with worse survival or disability despite being administered to more severely injured subjects. Ketamine exposure was associated with reduced elevations of ICP, more instances of seizure activity, and lower concentrations of TBI protein biomarkers.

Petrogenesis of the Niagara Icefalls Ultramafic-Mafic complex, Northern Victoria Land, Antarctica : Preliminary results

Austin T. Arias,Jung-Woo Park,Sang-Bong Yi,Mi Jung Lee 대한지질학회 2019 대한지질학회 학술대회 Vol.2019 No.10

Classification(s) of Cervical Deformity

Austin C. Kaidi,Han Jo Kim 대한척추신경외과학회 2022 Neurospine Vol.19 No.4

Cervical spine deformities (CSD) are complex surgical issues with currently heterogenous management strategies. The classification of CSD is still an evolving field. Rudimentary classification schemas were initially proposed in the late 20th century but were largely informal and based on the underlying etiology (i.e. , postsurgical, traumatic, or inflammatory). The first formal classification schema was proposed by Ames et al. in 2015 who established a standard nomenclature for describing these deformities. This classification system established 5 deformity descriptors based on curve apex location (cervical, cervicothoracic, thoracic, craniovertebral junctional, and coronal deformities) and 5 deformity modifiers which helped surgeons utilize a standard language when discussing CSD patients. Koller et al. in 2019 subsequently established a classification system for patients with rigid cervical kyphosis based on regional and global sagittal alignment. Most recently, Kim et al. in 2020 proposed an updated classification system utilizing dynamic cervical spine imaging to guide surgical treatment of CSD patients. It identified 4 major groups of deformities – (1) those with “flat-neck” deformities caused by cervical lordosis T1 slope mismatch; (2) those with focal kyphotic deformities between 2 cervical vertebrae; (3) those with cervicothoracic deformities caused by large T1 slope; and (4) those with coronal deformities. Group 2 deformities most often required combined anterior-posterior approaches with short constructs, and group 3 deformities most often required posterior-only approaches with 3-column osteotomies.

The Myth of Polarization Among Taiwanese Voters: The Missing Middle

Austin Horng-En Wang 동아시아연구원 2019 Journal of East Asian Studies Vol.19 No.3

Are Taiwanese voters polarized? By presenting four novel visualizations based on a factor analysis of Taiwan National Security Surveys from 2002 to 2017, this article describes the contours of structural change in Taiwan politics. Overall, the cross-strait position among Taiwanese voters can be described by a stable inverted U shape over time. This arises from the fact that most nonpartisans—typically neglected in the literature on polarization—are moderate. Before 2008, increasing polarization among partisans can be attributed to pan-green voters moving toward independence. Between 2008 and 2014, decreasing polarization stems from moderates self-identifying as panblue supporters. Since 2014, a record-breaking number of nonpartisans have left the pan-blue camp, and more extreme pan-blue voters have contributed to a return of polarization among partisans. The results yield important implications for the study of polarization and populism, as well as for the future of Taiwanese politics.

성능 기반 에어 필터의 교체 빈도

Austin Ronald Baird,Casiano Armenta,Peter Vorobieff,박창용(번역자) 대한설비공학회 2019 설비저널 Vol.48 No.1

The Role of Organizational Slack and Human Capital in Managing Performance Shocks: An Analysis of US Nursing Homes and Hurricane Katrina

Austin McCrea 서울대학교행정대학원 2022 The Korean Journal of Policy Studies Vol.37 No.3

Public service organizations employ buffers to ward off disruptive performance shocks such as disasters, budget cuts, and uncertain events. Existing applications on buffering focus on how slack human resources are reallocated to high-risk areas during times of uncertainty to dampen the impact these events have on core organizational processes. Besides slack, the quality of human capital is also important. Skilled personnel have the technical acumen and expertise to help managers navigate through treacherous times and still deliver public services. Yet, existing work does not disentangle the distinct impact of these two buffers. Using a panel dataset of nursing homes in Louisiana and Mississippi, I explore how personnel slack and human capital helped mitigate the devastation that Hurricane Katrina had on a very fragile, dependent, and sensitive segment of the population. The findings suggest that human capital buffers the impact of Hurricane Katrina on health deficiencies and physical dependency. In contrast, slack capacity amplified the impact of Katrina on health deficiencies.

APPROXIMATING COMMON FIXED POINT OF THREE MULTIVALUED MAPPINGS SATISFYING CONDITION (E) IN HYPERBOLIC SPACES

Austine Efut Ofem,Godwin Chidi Ugwunnadi,Ojen Kumar Narain,Jong Kyu Kim 경남대학교 기초과학연구소 2023 Nonlinear Functional Analysis and Applications Vol.28 No.3

In this article, we introduce the hyperbolic space version of a faster iterative algorithm. The proposed iterative algorithm is used to approximate the common fixed point of three multi-valued almost contraction mappings and three multi-valued mappings satisfying condition $(E)$ in hyperbolic spaces. The concepts weak $w^2$-stability involving three multi-valued almost contraction mappings are considered. Several strong and $\triangle$-convergence theorems of the suggested algorithm are proved in hyperbolic spaces. We provide an example to compare the performance of the proposed method with some well-known methods in the literature.

Evaluation of Microstructure, Hardness and Mechanical Properties of Friction Stir Welded Al–Ce–Si–Mg Aluminium Alloy

Austine D. D’Souza,Shrikantha S. Rao,Mervin A. Herbert 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.9

A vast majority of the research on friction stir welding(FSW) is mainly focused on welding of aluminium alloys. The researchstudies in this paper are based on one such alloy known as Al–Ce–Si–Mg aluminium alloy, of which, the microstructure andother mechanical properties of the friction stir welded joints are yet to be studied. The plates of Al–Ce–Si–Mg aluminiumalloy were friction stir welded using a non consumable, rotating tool with triangular profile pin and circular shoulder, withdifferent combinations of tool rotation speeds and weld speeds. The microstructure, hardness and mechanical properties ofthe weld were analyzed. The microstructure of the weld zones revealed that, the average grain size at the bottom of the NuggetZone (NZ) is 5 ± 0.12 μm and gradually increases to 15 ± 0.23 μm at the top of the NZ. In the TMAZ the grain size is20 ± 0.14 μm and is bigger compared to the NZ. In the HAZ, the grain size is around 37 ± 0.21 μm and is bigger than that inthe TMAZ. The maximum Vickers hardness value at the NZ center is 231.9 ± 2 Hv, and uniformly reduces to 100 ± 2.4 Hvin the TMAZ and 65 ± 1.3 Hv in the HAZ and then increases to 98 ± 1 Hv in the base material (BM). The maximum ultimatetensile strength (UTS) of FSW joint was found to be around 102.55 ± 3 MPa with elongation at fracture of 2.5%. The BMUTS was 154 ± 4.5 MPa. For a tool rotation speed of 800RPM and a weld speed of 20 mm/min a maximum joint efficiencyof 67%. was obtained. Hence these were chosen as the optimum process parameters to join the alloy Al–Ce–Si–Mg by FSW.