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Mathematical models for manufacturing a novel gear shaper cutter
Shen-Wang Lin,Cheng-Shun Han,Jiu-Bin Tan,Shen Dong 대한기계학회 2010 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.24 No.1
The design principle and models for novel error-free shaper cutters are discussed to improve the accuracy and service life of gear cutting tools. The modified methods for designing the tooth profile of the shaper cutter are developed by including the inverse envelope method, midpoint-midline method and midpoint-displacement method based on the theory of geometrical reverse problem. The universal mathematical models for manufacturing optimal tooth profile of shaper cutters are presented. The feasibility and reliability of the proposed principle, methods and models are proved by combining the numerical examples with practical application. The design method suggested in this paper is superior to the traditional design scheme, and will be helpful in facilitating the design and manufacture of shaper cutters.
Transmission loss of orthogonally stiffened laminated composite plates
Cheng Shen,Fengxian Xin,Tianjian Lu 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.1
Sound transmission through laminated composite plates reinforced by two sets of orthogonal stiffeners is investigated theoretically. Alayerwise shear deformable theory is used to model the vibration of the laminated composite face-panel; A governing equation of I sectioncomposite beam is introduced, which accounts for the extensional, flexural, torsional and their coupling effects. The Euler-Bernoullibeam theory and torsional wave equation are employed to describe the flexural and rotational motions of the rib stiffeners, respectively. The technique of Fourier transform is applied to solve the governing equations resulting in infinite sets of simultaneous algebraic coupledequations, which are numerically solved by truncating them into a finite range insofar as the solutions converge. The accuracy of thenumerical solutions is checked by comparing the present model predictions with existing literature. The validated model is subsequentlyemployed to quantify the effects of the spacing of the stiffeners and the stacking geometry of the laminated composite face-panel andstiffeners on sound transmission through the structure. It is demonstrated that both the stiffener spacing and the stacking geometry havesignificant influences on the sound transmission loss across the structure. The proposed theoretical model successfully characterizes theprocess of sound penetration through stiffened laminated composite plates, which should be much helpful for the practical design of suchstructures with acoustic requirements.
Further Education for Asian University Sports: AUSF Education and Development Centre
( Hao Cheng ),( Pei Liu ),( Jian Wang ),( Tieli Yang ),( Jun Xie ),( Bingshu Zhong ),( Qing Song ),( Cheng Fave Seetow ),( Yuetong Yan ),( Zhen Shen ),( Yanqing Xue ),( Kunning Chen ) 한국체육학회 2015 국제스포츠과학 학술대회 Vol.2015 No.1
( Fang Yu Cheng ),( Cheng Tang ),( Huan Yang ),( Hui Min Yu ),( Yu Chen ),( Zhong Yao Shen ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.3
Biosurfactants have versatile properties and potential industrial applications. A new producer, B. subtilis TU2, was isolated from the underground oil-extraction wastewater of Shengli Oilfield, China. Preliminary flask culture showed that the titer of biosurfactant obtained from the broth of TU2 was ~1.5 g/l at 48 h (718 mg/l after purification), with a reduced surface tension of 32.5 mN/m. The critical micelle concentration was measured as 50 mg/l and the surface tension maintained stability in solution with 50 g/l NaCl and 16 g/l CaCl2 after 5 days of incubation at 70oC. FT-IR spectra exhibited the structure information of both glycolipid and lipopeptide. MALDI-TOF-MS analyses confirmed that the biosurfactant produced by B. subtilis TU2 was a blend of glycolipid and lipopeptide, including rhamnolipid, surfactin, and fengycin. The blended biosurfactant showed 86% of oil-washing efficiency and fine emulsification activity on crude oil, suggesting its potential application in enhanced oil recovery.
Prediction of postoperative pancreatic fistula using a nomogram based on the updated definition
Cheng-Xiang Guo,Yi-Nan Shen,Qi Zhang,Xiao-Zhen Zhang,Jun-Li Wang,Shun-Liang Gao,Jian-Ying Lou,Ri-Sheng Que,Tao Ma,Ting-Bo Liang,Xue-Li Bai 대한외과학회 2020 Annals of Surgical Treatment and Research(ASRT) Vol.98 No.2
Purpose: The International Study Group on Pancreatic Fistula’s definition of postoperative pancreatic fistula (POPF) has recently been updated. This study aimed to identify risk factors for POPF in patients having pancreaticoduodenectomy (PD) and to generate a nomogram to predict POPF. Methods: Data on 298 patients who underwent PD from March 2012 to October 2017 was retrospectively reviewed and POPF statuses were redefined. A nomogram was constructed using data from 220 patients and validated using the remaining 78 patients. Independent risk factors for POPF were identified using univariate and multivariate analyses. A predictive nomogram was established based on the independent risk factors and was compared with existing models. Results: Texture of the pancreas, size of the main pancreatic duct, portal vein invasion, and definitive pathology were the identified risk factors. The nomogram had a C-index of 0.793 and was internally validated. The nomogram performed better (C-index of 0.816) than the other most cited models (C-indexes of 0.728 and 0.735) in the validation cohort. In addition, the nomogram can assign patients into low- (less than 10%), intermediate- (10% to 30%), and high-risk (equal or higher than 30%) groups to facilitate personalized management. Conclusion: The nomogram accurately predicted POPF in patients having PD.
Cheng, Yeong-Hsiang,Shen, Tian-Fuh,Chen, Bao-Ji Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.11
The purpose of this study was to investigate the effects of aflatoxin $B_1$ ($AFB_1$) on the ultracellular morphology alteration, apoptosis induction and reactive nitrogen and oxygen intermediates production of peritoneal macrophages (DPM) from mule ducks. The ducklings were purchased from a commercial hatchery, and were fed a corn-soybean based diet. As the ducklings were grown up to 3 wk of age, the Sephadex-elicited peritoneal exudative cells (PEC) were used as the source for duck peritoneal macrophages. The ultracellular morphology study showed that significant number of cells shifted from category I (normal cell with ruffled membrane) and II (cell membrane blebbing) to category III (cell membrane blebbing and even rupture) after DPM were incubated with $AFB_1$ ($20{\mu}g/ml$) for 12 to 48 h. When DPM were exposed to $AFB_1$ in vitro, the production of NO, $H_2O_2$ and $O_2{^-}$ in macrophages was reduced after 12-48 h incubation with previous LPS stimulation. There was a DNA laddering pattern observed in DPM incubated with $AFB_1$ 5, 10, 20, 50 or $100{\mu}g/ml$ for 12 h. Evidence also revealed that the percentage of apoptotic cells was increased along with the elevation of $AFB_1$ concentration. The results suggest that $AFB_1$ exposure causes duck macrophages going on apoptotic pathway through evidence of ultracellular morphology alteration and DNA laddering in agarose electrophoresis. The production of reactive nitrogen and oxygen intermediates of duck macrophages also depressed after $AFB_1$ exposure, and this implied that $AFB_1$ could cause deteriorated functions of bacteriocidal and tumoricidal activity in duck macrophages.
Cheng, C.H.,Ou, B.R.,Shen, T.F.,Ding, Shih-Torng Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.7
The current study was designed to determine the effects of dietary docosahexaenoic acid (DHA) on fatty acid deposition in egg yolk and various tissues of laying Tsaiya ducks, and on the mRNA concentrations of hepatic lipogenesis-related transcription factors. Thirty laying ducks were randomly assigned to three treatments with diets based on corn-soybean meal (ME: 2803 kcal/kg; CP: 17.1%; Ca: 3.4%) supplemented with 0% (control diet), 0.5% or 2% algal DHA oil. The DHA content in egg yolks of the ducks was elevated significantly (p<0.01) with the supplementation of dietary DHA. The DHA percentage of the total fatty acids in the egg yolk of laying ducks was 0.5%, 1.3% and 3.4% for 0%, 0.5% and 2% algal DHA oil treatments, respectively, for the $1^{st}$ week, and 0.5%, 1.5% and 3.3% for the $2^{nd}$ week. Therefore, algal DHA oil can be utilized by laying Tsaiya ducks to enhance the egg-yolk DHA content. The concentrations of triacylglycerol (TG) and cholesterol in plasma of laying Tsaiya ducks were not affected by dietary DHA treatments (p>0.05). The DHA concentration in plasma, liver, and skeletal muscle was increased with the addition of dietary algal DHA oil (p<0.05). The mRNA abundance of sterol regulatory element binding protein 1 (SREBP1) and SREBP2 in the livers of laying Tsaiya ducks was not affected by dietary DHA, suggesting that the expression of these transcription factors is tightly controlled and not sensitive to DHA treatments.
Shen-En Chou,Cheng-Hsi Yeh,Shun-Yu Chi,Fong-Fu Chou,Yi-Ju Wu,Yen-Hsiang Chang,Yi-Chia Chan 대한외과학회 2024 Annals of Surgical Treatment and Research(ASRT) Vol.107 No.3
Purpose: Preoperative localization plays an important role in secondary hyperparathyroidism (SHPT) surgery. The advantages of neck ultrasound (US) include high availability and low cost. However, the reported sensitivity of US is 54%– 76%, and the reason for missed parathyroid glands (PGs) on US has been rarely addressed. Methods: Fifty-four patients who were diagnosed with renal SHPT from September 2020 to March 2022 were included in this retrospective study. Preoperative localization included surgeon-oriented US and technetium 99m-sestamibi single- photon emission CT (SPECT)/CT. Results: A total of 212 PGs were pathologically confirmed, resulting in a success rate of 96.2% (52 of 54). Using echo, 193 PGs (91.0%) were accurately localized, while 19 glands (9.0%) were not identified, including those in ectopic positions (n = 12, at thymus or intrathyroid or others), of small size (<1 cm, n = 6), or overlapping with an ipsilateral PG (n = 1). US accurately detected 4 PGs in 36 (66.7%) patients, while SPECT/CT localized 4 glands in 19 patients (35.2%). Although the number of US-detectable PGs was not associated with success rate, it showed a significant negative correlation with surgical time (rs = –0.459, P = 0.002). Conclusion: US detected 4 glands in 66% of SHPT patients with a sensitivity of 90% for localization. Ectopic position and small size were the most common reasons for the failure to detect PG on US. Complete preoperative echo localization might shorten operating time.
Shen, Chien-Hung,Chang, Yu-Cheng,Wu, Po-Ting,Diau, Eric Wei-Guang Korean Society of Photoscience 2014 Rapid communication in photoscience Vol.3 No.1
Anodic self-organized titania nanotube (TNT) arrays have a great potential as efficient electron-transport materials for dye-sensitized solar cells (DSSC). Herewith we report the photovoltaic and kinetic investigations for a series of heteroleptic ruthenium complexes (RD16-RD18) sensitized on TNT films for DSSC applications. We found that the RD16 device had an enhanced short-circuit current density ($J_{SC}/mAcm^{-2}=15.0$) and an efficiency of power conversion (${\eta}=7.2%$) greater than that of a N719 device (${\eta}=7.1%$) due to the increasing light-harvesting and the broadened spectral features with thiophene-based ligands. However, the device made of RD17 (adding one more hexyl chain) showed smaller $J_{SC}(14.1mAcm^{-2})$ and poorer ${\eta}(6.8%)$ compare to those of RD16 due to smaller amount of dye-loading and less efficient electron injection for the RD17 device than for the RD16 device. For the RD18 dye (adding one more thiophene unit and one more hexyl chain), we found that the device showed even lower $J_{SC}(13.2mAcm^{-2}) $ that led to a poorest device performance (${\eta}=6.2%$) for the RD18 device. These results are against to those obtained from the same dyes sensitized on $TiO_2$ nanoparticle films and they can be rationalized according to the electron transport kinetics measured using the methods of charge extraction and transient photovoltage decays.