http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Friesen, Melissa C,Locke, Sarah J,Zaebst, Dennis,Viet, Susan,Shortreed, Susan,Chen, Yu-Cheng,Koh, Dong-Hee,Pardo, Larissa,Schwartz, Kendra L,Davis, Faith G,Stewart, Patricia A,Colt, Joanne S,Purdue, M BMJ Publishing Group Ltd 2014 Occupational and environmental medicine Vol.71 No.suppl1
<P><B>Objectives</B></P><P>We applied machine learning approaches to efficiently assist multiple experts to transparently estimate occupational lead exposure in a case-control study of renal cell carcinoma.</P><P><B>Method</B></P><P>We used hierarchical cluster models to classify the 7154 study jobs with occupational history and job/industry questionnaires into 360 groups with similar responses. Each group was reviewed independently by two or three experts and was assigned probabilities of lead exposure (<5%, ≥5– <50%, ≥50%) for three time periods (<1980, 1980–1994, ≥1995). When the group’s mean response pattern suggested within-group exposure variability, experts identified programmable conditions that defined the rating differences where possible or flagged the group for further review. After splitting jobs that overlapped time periods at the calendar cut point, the 9992 job/time periods were assigned their relevant expert/group/time period estimate. Classification and regression tree (CART) models were developed to predict each expert’s expected assignment, based on previous decisions, to assign estimates for jobs in groups that expert had not assessed and for jobs requiring further review.</P><P><B>Results</B></P><P>In preliminary analyses, CART models predicted 91–96% of the experts’ pre-1995 estimates and 77–96% of ≥1995 estimates. CART estimates were assigned to 3–48% of the job/time periods, varying by expert. Overall, 92% of the job/time periods were assigned the same estimate by at least two experts.</P><P><B>Conclusions</B></P><P>Our framework reduced the number of exposure decisions needed from each expert compared to job-by-job assessment. Future work will use CART models to identify differences between experts to be resolved and incorporate frequency and intensity of lead exposure estimates.</P>
Student Anxiety and Motivation of Speaking English in Conversation Class: A Case Study
Paul Friesen,Nahk-Bohk Kim 한국영어어문교육학회 2020 영어어문교육 Vol.26 No.4
To build confidence to engage in conversation it is crucial to motivate and reduce anxiety in EFL learners. This case study will focus on analyzing students’ per-ceived anxiety, its effect on their motivation to speak English, and suggest strate-gies to decrease anxiety while increasing motivation. Research data consisted of a Google form survey, self-reflection questionnaire, and one-on-one interviews. Surveys were given as a Google form on the students’ phones, consisting of 46 students taking a mandatory weekly English Conversation course in the second semester of 2019 at a South Korean university. To identify the impact on the stu-dents’ conversational anxiety and motivation, the qualitative study method was utilized. In the pre/post questionnaire some significant changes were found in both anxiety and motivation. The questions were designed to be self-reflective leading to more honest answers. The findings show focused activities requiring longer re-sponses lowered students’ anxiety and increased motivation to speak. Lack of mo-tivation changed little from beginning to end, from the questionnaire data, sug-gesting students’ prior experience provided the framework. Exposure to criticism from peers, who are not in the common friend circle, challenges the short-term fear barrier and is not related to English per se.
열차상태감시 및 진단시스템 COMORAN 개발 및 적용결과 소개
Ulf Friesen,Marc-Oliver Herden,Matthaeus Englbrecht,Young Mo Kim 한국철도학회 2012 한국철도학회 학술발표대회논문집 Vol.2012 No.5
현재 도시철도 및 고속철도 차량에 대한 속도 증가 및 승객 수송량에 대한 요구가 증가되고 있다. 이러한 경향에 맞춰 TSI 규정에서는 철도차량 운행에 따른 안전규정을 강화하고 있다. TSI 규정에 따르면 모든 고속철도차량은 DNRA(Detection of Non-Rotating Axles)기능을 탑재하고 있어야 한다. DNRA는 주행안전 감지, 엑슬박스 온도 감지, 그리고 탈선 감지 기능을 포함한다. 효율적인 열차운영 측면에서, 기존에 있는 차량에 단순히 이러한 기능을 구현할 수 있는 장치를 장착함으로써 TSI 규정을 만족할 수 있는 장비의 개발이 요구 되었다. 이러한 요구사항을 충족하기 위해 Knorr-Bremse사와 SKF사가 공동으로 최소한의 장비로 최대한의 기능을 발휘할 수 있는 COMORAN 시스템을 개발하여, 현재 독일에서 운행하고 있는 차량에 장착하여, 기능을 입증하였다. 다음에서는 개발된 COMORAN의 기능과 적용 결과에 대한 소개를 하겠다.
The Climbing Tower - Creating physical challenges for youth in a non-digital environment
Stanley K. Friesen,Grant Gehman 한국디지털디자인협의회 2014 (사)한국디지털디자인협의회 conference Vol.2014 No.5
Much of today’s entertainment for young people is based on electronic media ? from hand held games to multi-player immersive video environments. As a result, many children are not in good physical shape, and their view of reality is skewed by over stimulation visually, and under stimulation physically.
Liao, Linda M,Friesen, Melissa C,Xiang, Yong-Bing,Cai, Hui,Koh, Dong-Hee,Ji, Bu-Tian,Yang, Gong,Li, Hong-Lan,Locke, Sarah J,Rothman, Nathaniel,Zheng, Wei,Gao, Yu-Tang,Shu, Xiao-Ou,Purdue, Mark P BMJ Publishing Group Ltd 2014 Occupational and environmental medicine Vol.71 No.suppl1
<P><B>Objectives</B></P><P>Epidemiologic studies of occupational lead exposure have suggested increased risks of cancers of the brain, kidney, lung, meninges, and stomach; however, the totality of the evidence is inconsistent. To clarify whether lead is a carcinogen, we investigated the relationship between occupational lead exposure and risks of these five cancer sites in two prospective cohort studies in Shanghai, China.</P><P><B>Method</B></P><P>Annual job/industry-specific estimates of lead fume and lead dust exposure were derived from a statistical model that combined expert ratings of lead intensity with inspection measurements collected by the Shanghai Centre for Disease Control and Prevention. The job/industry estimates were applied to the lifetime work histories of subjects from the Shanghai Women’s Health Study (73 363 participants) and the Shanghai Men’s Health Study (61 379 participants) to estimate cumulative exposure to lead dust and lead fume. Cohort-specific relative hazard rate ratios (RRs) and 95% confidence intervals (CI) were estimated using Cox proportional hazards regression models and then pooled using a random effects meta-analysis model.</P><P><B>Results</B></P><P>We observed a statistically significant increased risk of meningioma among individuals with estimated occupational exposure to lead dust or fumes (RR=2.4, 95% CI:1.1–5.0), and in particular among those with an above-median cumulative exposure to dust or fumes (RR=3.1, 95% CI:1.3–7.4). We observed suggestive associations with lead exposure for cancers of the kidney (RR=1.4, 95% CI:0.9–2.3) and brain (RR=1.8, 95% CI:0.7–4.8), and null findings for cancers of the lung and stomach.</P><P><B>Conclusions</B></P><P>Our findings provide additional evidence that occupational lead exposure increases risk of meningioma.</P>
Jin, Dahee,Song, Danoh,Friesen, Alex,Lee, Yong Min,Ryou, Myung-Hyun Pergamon Press 2018 Electrochimica Acta Vol. No.
<P><B>Abstract</B></P> <P>To improve the electrochemical properties of LiNi<SUB>1/3</SUB>Co<SUB>1/3</SUB>Mn<SUB>1/3</SUB>O<SUB>2</SUB> (NCM) under the high-voltage operating condition of 4.5 V, 0.5 wt.% of alumina (Al<SUB>2</SUB>O<SUB>3</SUB>) was introduced as a ceramic filler during NCM cathode preparation. Uniformly dispersed Al<SUB>2</SUB>O<SUB>3</SUB> over the entire area of the NCM cathodes efficiently stabilized the oxidative decomposition of the liquid electrolyte up to 5.3 V. This behavior hindered the formation of a thick surface film on the NCM cathodes after high-voltage operation (4.5 V). The Al<SUB>2</SUB>O<SUB>3</SUB>-containing NCM cathodes (NCM/Al<SUB>2</SUB>O<SUB>3</SUB>) revealed much smaller total cell resistance compared to the bare NCM cathodes, resulting in improved cycle performance and rate capabilities, which were identified as a facilitated Li<SUP>+</SUP> diffusion in presence of the Al<SUB>2</SUB>O<SUB>3</SUB> particles. NCM/Al<SUB>2</SUB>O<SUB>3</SUB> showed a 29.4% improvement over the bare NCM (79.3 and 112.3 mAhh g<SUP>−1</SUP> for bare NCM and NCM/Al<SUB>2</SUB>O<SUB>3</SUB>, respectively, after the 100<SUP>th</SUP> cycle) at 3C (4.3 V cutoff, C/2 for charging and 3C for discharging processes) and a 53.5% improvement (35.0 and 75.3 mAhh g<SUP>−1</SUP> for NCM/Al<SUB>2</SUB>O<SUB>3</SUB> and bare NCM, respectively) at 5C (4.5 V cutoff).</P> <P><B>Highlights</B></P> <P> <UL> <LI> Alumina (Al<SUB>2</SUB>O<SUB>3</SUB>) was introduced as ceramic filler during NCM cathode preparation. </LI> <LI> Al<SUB>2</SUB>O<SUB>3</SUB> stabilized oxidative decomposition of liquid electrolyte (∼5.3 V vs. Li/Li<SUP>+</SUP>). </LI> <LI> Al<SUB>2</SUB>O<SUB>3</SUB> showed significant improvement in high voltage operating condition. </LI> <LI> Al<SUB>2</SUB>O<SUB>3</SUB> showed significant improvement in cycle performance and rate capability. </LI> </UL> </P>
Jin, Dahee,Oh, Jeonghun,Friesen, Alex,Kim, Kyuman,Jo, Taejin,Lee, Yong Min,Ryou, Myung-Hyun American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.19
<P>The commercialization of Li metal electrodes is a long-standing objective in the battery community. To accomplish this goal, the formation of Li dendrites and mossy Li deposition, which cause poor cycle performance and safety issues, must be resolved. In addition, it is necessary to develop wide and thin Li metal anodes to increase not only the energy density, but also the design freedom of large-scale Li-metal-based batteries. We solved both issues by developing a novel approach involving the application of calendared stabilized Li metal powder (LiMP) electrodes as anodes. In this study, we fabricated a 21.5 cm wide and 40 μm thick compressed LiMP electrode and investigated the correlation between the compression level and electrochemical performance. A high level of compression (40% compression) physically activated the LiMP surface to suppress the dendritic and mossy Li metal formation at high current densities. Furthermore, as a result of the LiMP self-healing because of electrochemical activation, the 40% compressed LiMP electrode exhibited an excellent cycle performance (reaching 90% of the initial discharge capacity after the 360th cycle), which was improved by more than a factor of 2 compared to that of a flat Li metal foil with the same thickness (90% of the initial discharge capacity after the 150th cycle).</P> [FIG OMISSION]</BR>