Mathematical Model and Tooth Contact Analysis of an Internal Helical Gear Pair with Selectable Contact Path

Shuai Peng,Bingkui Chen,Dong Liang,Lu-he Zhang,Si-ling Qin 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.6

An internal helical gear pair with point contact pattern based on the space meshing theory is proposed which consists of an involute internal gear and a pinion with quadratic curve profile. Particularly, the contact path of the tooth surface is selectable, which can inherit the characteristic of the surface. Moreover, this type of internal gear pair has lower sensitivity to assembly errors. The generation principle and mathematical model is presented. The motion simulation and adaptability to center distance error of the internal gear pair are discussed. The gear pair is manufactured. Based on the mathematical model and tooth contact analysis (TCA) method, the locations of contact points and kinematic errors are determined under different center distance variation and axial misalignments. The simulated results reveal that the locations of contact points of the gear and pinion change under assembly errors. Little kinematic error occurs under axial misalignment. No edge contact occurs under any assembly error condition. Experiment study is performed and the result is consistent with the theoretical analysis.

Effect of stacking conditions on performance of a centrifugal pump

Peng Yan,Shiyang Li,Shuai Yang,Peng Wu,Dazhuan Wu 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.2

In this study, the effect of stacking condition of centrifugal pump impeller was investigated by Computational fluid dynamics (CFD). The performance curves of impellers with three different stacking conditions were compared. The Local Euler head distributions (LEH distribution) at blade Leading edge (LE) and Trailing edge (TE) were obtained to evaluate the contribution of different spanwise location to the total work. The positive stacking characterised by the hub leading the shroud was considered inappropriate in centrifugal pump impellers as it deteriorated the performance of the pump in whole flow rate range. The negative stacking characterised by the shroud leading the hub could improve flow stability and efficiency in low flow rates, it was manufactured and tested. The test results showed good agreement with CFD calculations. A hump zone was observed in zero stacking impeller between 0.9Q d and Q d . It was closely related to the drastic change in pattern of LEH distribution at the two flow rates. The internal flow was analyzed to reveal the reasons responsible for the hump in head curve. It is found that the tremendous extension of low streamwise velocity region and its instant movement from the corner of shroud and blade suction surface to the midspan near blade suction surface when the flow rate decreases from Q dto 0.9Q d is the main reason for flow instability in zero stacking impeller.

Investigation on purification of α-Fe2O3 from zinc smelting iron slag by superconducting HGMS technology

Peng Zhang,Su-qin Li,Zi-jie Guo,Chang-quan Zhang,Chang-qiao Yang,Shuai-shuai Han 한국초전도.저온공학회 2018 한국초전도저온공학회논문지 Vol.20 No.2

Comprehensive utilization of zinc smelting iron slag not only solves environmental problems but also creates huge economic benefits. This study was conducted on the enrichment and recovery of α-Fe2O3 from zinc smelting iron slag by superconducting HGMS technology. Several variables such as slurry flow velocity, slag concentration, magnetic field intensity and the amount of dispersing agent were tested in magnetic separation. In the experiments, obtained optimal magnetic separation parameters were 1.60 T of magnetic flux intensity, 600 mL/min of slurry flow velocity of, 15 g/L of slag concentration of, 0.10 g/L of dispersing agent. Under this condition, the content of α-Fe2O3 was increased from 86.22% to 94.39% that can approach the Chinese national standard requirements (A level) of iron oxide red. It was concluded that using superconducting HGMS technology was an effective method for the purification of α-Fe2O3 from zinc smelting iron slag.

A Stiffness Modeling Approach for Multi-Leaf Spring Mechanism Supporting Coupling Error Analysis of Nano- Stages

Shuai-Shuai Lu,Peng Yan 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.6

In the present paper, we take the multi-leaf spring mechanism as a particular element to develop a modeling approach for the stiffness by considering the coupling effects of the cross axis force. With this, a more accurate model of the multi-leaf spring based nano-stage is derived by incorporating the effect of cross axis input force, which can better predict the coupling error. The new analytical model indicates that the total axial stiffness is an inverse-quadratic function of the cross axis input load instead of a constant value, which can be used to analyze the cross axis coupling error of multi-leaf spring based nano-stages. The proposed analysis method is then verified by FEA and experiments, where excellent results are demonstrated in predicting the cross axis coupling effects of nano-stages such as stiffness variation and coupling error. The proposed approach offers a new look into the design and manipulation of multileaf spring based nano-stages.

농촌지역축제에 영향을 미치는 다양한 환경요인의 비교 분석: 영동군과 금산군의 비교를 중심으로

팽수(Peng, Shuai),백성우,김주호,정강환 관광경영학회 2019 관광경영연구 Vol.93 No.-

With the expansion of big cities and the possibility of the disappearance of small provincial cities increasing, the regional festival, which is held in the rural areas, plays a very important role as a regional tourism and promotion strategy. In particular, there is a need to look at the problem environment of the current rural festival, which forms a pillar of tourism in rural areas. In addition, a turning point is required to break down the manners of the annual Rural Community Festival, which has been operated on a regular basis, and to add vitality to the Rural Community Festival by finding a determinant that impedes the development of the Rural Community Festival. For this, it is necessary to find out whether the multi-sided factors in rural communities are ffecting the current rural festivals. In this study, the analysis of the multi-sided factors in rural areas where the environment in the rural areas held by Geumsan County in South Chungcheong Province and Yeongdong County in North Chungcheong Province affects the regional festivals and the comparison of the differences between the two regions was made.The important findings of this study showed that the exploratory factor analysis in rural areas showed that the determinant influencing regional festivals held in Yeongdong County, North Chungcheong Province, the purpose of the study, and Geumsan County, South Chungcheong Province, was a "deterioration of growth momentum." Yeongdong County in North Chungcheong Province and Geumsan County in South Chungcheong Province, among other factors, have been analyzed that the long-term strategy of rural areas is an important factor for regional festivals, and among the "decrease in growth momentum," the "difference in income of residents," the "future food problem in rural areas" and the "continued population reduction" have been analyzed as important determinants affecting the rural festivals, which are the most important factors for the future growth of rural areas.

중국관광객의 한국방문동기 시장세분화 연구

팽수(Peng, Shuai),남문희(Nam, Moon-Hee),정강환(Jeong, Gang-Hoan) 한국문화산업학회 2016 문화산업연구 Vol.16 No.2

유엔세계관광기구(UNWTO)는 중국이 미국, 일본, 독일에 이어 세계 4위의 관광객 수출국이 될 것이며, 2020년에는 중국인 해외여행객 수가 2억 명까지 증가하여 단일 국가시장으로서는 세계 최대의 관광국이 될 것으로 예측하고 있다. 방한 중국관광객은 2000년부터 지속적으로 증가하는 추세이다. 2008년 북경올림픽 개최이후 해외여행 자유화로 인해 중국관광객이 한국을 방문하는 비율은 계속 증가하였으며, 2010년 7월 이후부터는 중국 관광객이 일본을 제치고 한국의 외래 관광객 1위를 차지하였다. 본 연구는 꾸준히 증가하고 있는 방한 중국 관광객의 한국 방문 동기가 무엇인지를 분석하고, 이를 토대로 중국관광객들의 한국방문동기에 따른 시장세분화를 통해 관광객 시장의 특성을 파악하여, 관광사업의 관리와 마케팅전략 등을 창출하고자 한다. 연구목적 달성을 위해 방한 중국관광객을 대상으로 실증 조사를 시행한 후, 요인분석(factor analysis)을 통해 중국관광객의 방문동기에 관한 잠재적 요인을 분석하였다. 군집분석(cluster analysis)을 통해 방문객의 방문동기에 따라서 유사한 그룹을 구분하였으며, 교차분석(cross-tab analysis)을 통해 인구통계학적 특성과 관광형태, 그리고 관광선호도 측면에서 군집 간의 차이점을 탐구하였다. 분석결과, 방한 중국관광객에 대한 방문동기에서 신기성,문화탐색성,일탈성,휴가성,사교성,가족친목성 등의 요인을 탐구하였으며, 관광객의 방문동기요인에 따른 방한 중국관광객의 군집분석 결과, 문화친목추구 집단, 휴가일탈추구 집단, 다목적추구 집단, 저동기 집단 등 4개의 군집을 도출하였다. 또한 각 군집과 관광객의 인구통계학적특성 및 관광형태, 그리고 관광선호도 특성과의 교차분석 결과, 방한 중국관광객의 연령, 학력, 직업, 월평균소득, 혼인상태, 방문경험, 동반형태, 거주지, 정보원천, 스타, 축제, 기념품의 변수에서 각 군집 간에 유의한 차이가 있는 것을 확인하였다. 또한 한국을 방문하는 중국관광객은 한국의 화장품과 미용상품, 스트레스 해소를 위한 문화이벤트, 다양한 장르의 축제 등에 관심이 많으며, 한국만의 매력을 만끽할 수 있는 문화와 자연환경 등에도 관심이 높을 뿐만 아니라 한국관광지의 관광시설과 유흥상품, 한류문화 등에도 높은 기대를 갖고 있는 것을 확인하였다. 이러한 연구결과를 바탕으로 중국관광객의 성향과 방문동기에 맞춘 지속적인 한류상품 개발이 필요할 것으로 판단된다. UNWTO(UN World Tourism Organization) has predicted that China will be world’s 4th largest tourist importing country, and by 2020, number of Chinese foreign tourist will reach to 2billion, naming it the largest tourism country. The Chinese tourists to coming to Korea is constantly increasing since 2000. Since the liberalization of overseas tourism after 2008 Beijing Olympic, the rate of Chinese tourists visiting Korea has constantly increased and since July 2010, Chinese tourists has exceeded Japanese tourists and became the largest visitor group. This research aims to analyze the motivation of Chinese tourists and identify tourist’s characteristics through market segmentation on their motivations of visiting Korea to generate marketing strategy and management of tourism industry. In order to achieve research objective, empirical research is conducted and analyzed substantial cause of motivation to visit through factor analysis. Through cluster analysis, the visitors were classified by similarity in their motivation to visit and by cross-tab analysis, the difference in demographic characteristic, form of tourism and tourism preferences were identified. As a result, in motivation of visiting Korea, novelty, cultural venture, deviation, vacation, sociality and family relation were analyzed. As a result of cluster analysis, cultural relationship group, vacation-deviation group, multiple caused group and low-motivational group were identified. Also, as a result of cross-tab analysis of each group and visitor’s democratic characteristic, form of tourism and tourism preferences, the meaningful difference among groups in age, education, job, income, marital status, visiting experience, company, residence, source of information, celebrity, festival and souvenir were identified. Moreover, Chinese tourists visiting Korea are highly interested in cosmetics, stress relieving cultural event and multi-genre festivals along with Korean unique culture, nature, tourist attraction, entertainment product and Hallyu (Korean wave) culture. Based on this research, the need for constant development of tourism product according to Chinese tourists’ motivation of visit arises. 유엔세계관광기구(UNWTO)는 중국이 미국, 일본, 독일에 이어 세계 4위의 관광객 수출국이 될 것이며, 2020년에는 중국인 해외여행객 수가 2억 명까지 증가하여 단일 국가시장으로서는 세계 최대의 관광국이 될 것으로 예측하고 있다. 방한 중국관광객은 2000년부터 지속적으로 증가하는 추세이다. 2008년 북경올림픽 개최이후 해외여행 자유화로 인해 중국관광객이 한국을 방문하는 비율은 계속 증가하였으며, 2010년 7월 이후부터는 중국 관광객이 일본을 제치고 한국의 외래 관광객 1위를 차지하였다. 본 연구는 꾸준히 증가하고 있는 방한 중국 관광객의 한국 방문 동기가 무엇인지를 분석하고, 이를 토대로 중국관광객들의 한국방문동기에 따른 시장세분화를 통해 관광객 시장의 특성을 파악하여, 관광사업의 관리와 마케팅전략 등을 창출하고자 한다. 연구목적 달성을 위해 방한 중국관광객을 대상으로 실증 조사를 시행한 후, 요인분석(factor analysis)을 통해 중국관광객의 방문동기에 관한 잠재적 요인을 분석하였다. 군집분석(cluster analysis)을 통해 방문객의 방문동기에 따라서 유사한 그룹을 구분하였으며, 교차분석(cross-tab analysis)을 통해 인구통계학적 특성과 관광형태, 그리고 관광선호도 측면에서 군집 간의 차이점을 탐구하였다. 분석결과, 방한 중국관광객에 대한 방문동기에서 신기성,문화탐색성,일탈성,휴가성,사교성,가족친목성 등의 요인을 탐구하였으며, 관광객의 방문동기요인에 따른 방한 중국관광객의 군집분석 결과, 문화친목추구 집단, 휴가일탈추구 집단, 다목적추구 집단, 저동기 집단 등 4개의 군집을 도출하였다. 또한 각 군집과 관광객의 인구통계학적특성 및 관광형태, 그리고 관광선호도 특성과의 교차분석 결과, 방한 중국관광객의 연령, 학력, 직업, 월평균소득, 혼인상태, 방문경험, 동반형태, 거주지, 정보원천, 스타, 축제, 기념품의 변수에서 각 군집 간에 유의한 차이가 있는 것을 확인하였다. 또한 한국을 방문하는 중국관광객은 한국의 화장품과 미용상품, 스트레스 해소를 위한 문화이벤트, 다양한 장르의 축제 등에 관심이 많으며, 한국만의 매력을 만끽할 수 있는 문화와 자연환경 등에도 관심이 높을 뿐만 아니라 한국관광지의 관광시설과 유흥상품, 한류문화 등에도 높은 기대를 갖고 있는 것을 확인하였다. 이러한 연구결과를 바탕으로 중국관광객의 성향과 방문동기에 맞춘 지속적인 한류상품 개발이 필요할 것으로 판단된다. UNWTO(UN World Tourism Organization) has predicted that China will be world’s 4th largest tourist importing country, and by 2020, number of Chinese foreign tourist will reach to 2billion, naming it the largest tourism country. The Chinese tourists to coming to Korea is constantly increasing since 2000. Since the liberalization of overseas tourism after 2008 Beijing Olympic, the rate of Chinese tourists visiting Korea has constantly increased and since July 2010, Chinese tourists has exceeded Japanese tourists and became the largest visitor group. This research aims to analyze the motivation of Chinese tourists and identify tourist’s characteristics through market segmentation on their motivations of visiting Korea to generate marketing strategy and management of tourism industry. In order to achieve research objective, empirical research is conducted and analyzed substantial cause of motivation to visit through factor analysis. Through cluster analysis, the visitors were classified by similarity in their motivation to visit and by cross-tab analysis, the difference in demographic characteristic, form of tourism and tourism preferences were identified. As a result, in motivation of visiting Korea, novelty, cultural venture, deviation, vacation, sociality and family relation were analyzed. As a result of cluster analysis, cultural relationship group, vacation-deviation group, multiple caused group and low-motivational group were identified. Also, as a result of cross-tab analysis of each group and visitor’s democratic characteristic, form of tourism and tourism preferences, the meaningful difference among groups in age, education, job, income, marital status, visiting experience, company, residence, source of information, celebrity, festival and souvenir were identified. Moreover, Chinese tourists visiting Korea are highly interested in cosmetics, stress relieving cultural event and multi-genre festivals along with Korean unique culture, nature, tourist attraction, entertainment product and Hallyu (Korean wave) culture. Based on this research, the need for constant development of tourism product according to Chinese tourists’ motivation of visit arises.

Construction of magnetic nanochains to achieve magnetic energy coupling in scaffold

Cijun Shuai,Xuan Chen,Chongxian He,Guowen Qian,Yang Shuai,SHUPING PENG,Youwen Deng,Wenjing Yang 한국생체재료학회 2022 생체재료학회지 Vol.26 No.3

Background: Fe3O4 nanoparticles are highly desired for constructing endogenous magnetic microenvironment in scaffold to accelerate bone regeneration due to their superior magnetism. However, their random arrangement easily leads to mutual consumption of magnetic poles, thereby weakening the magnetic stimulation effect. Methods: In this study, magnetic nanochains are synthesized by magnetic-field-guided interface co-assembly of Fe3O4 nanoparticles. In detail, multiple Fe3O4 nanoparticles are aligned along the direction of magnetic force lines and are connected in series to form nanochain structures under an external magnetic field. Subsequently, the nanochain structures are covered and fixed by depositing a thin layer of silica (SiO2), and consequently forming linear magnetic nanochains (Fe3O4@SiO2). The Fe3O4@SiO2 nanochains are then incorporated into poly l-lactic acid (PLLA) scaffold prepared by selective laser sintering technology. Results: The results show that the Fe3O4@SiO2 nanochains with unique core–shell structure are successfully constructed. Meanwhile, the orderly assembly of nanoparticles in the Fe3O4@SiO2 nanochains enable to form magnetic energy coupling and obtain a highly magnetic micro-field. The in vitro tests indicate that the PLLA/Fe3O4@SiO2 scaffolds exhibit superior capacity in enhancing cell activity, improving osteogenesis-related gene expressions, and inducing cell mineralization compared with PLLA and PLLA/Fe3O4 scaffolds. Conclusion: In short, the Fe3O4@SiO2 nanochains endow scaffolds with good magnetism and cytocompatibility, which have great potential in accelerating bone repair

Investigation on purification of α-Fe₂O₃ from zinc smelting iron slag by superconducting HGMS technology

Zhang, Peng,Li, Su-qin,Guo, Zi-jie,Zhang, Chang-quan,Yang, Chang-qiao,Han, Shuai-shuai The Korea Institute of Applied Superconductivity a 2018 한국초전도저온공학회논문지 Vol.20 No.2

Comprehensive utilization of zinc smelting iron slag not only solves environmental problems but also creates huge economic benefits. This study was conducted on the enrichment and recovery of ${\alpha}-Fe_2O_3$ from zinc smelting iron slag by superconducting HGMS technology. Several variables such as slurry flow velocity, slag concentration, magnetic field intensity and the amount of dispersing agent were tested in magnetic separation. In the experiments, obtained optimal magnetic separation parameters were 1.60 T of magnetic flux intensity, 600 mL/min of slurry flow velocity of, 15 g/L of slag concentration of, 0.10 g/L of dispersing agent. Under this condition, the content of ${\alpha}-Fe_2O_3$ was increased from 86.22% to 94.39% that can approach the Chinese national standard requirements (A level) of iron oxide red. It was concluded that using superconducting HGMS technology was an effective method for the purification of ${\alpha}-Fe_2O_3$ from zinc smelting iron slag.

Application of S-HGMS and chemical coupling technology in river water treatment

Xin Zhao,Su-qin Li,Shuai-shuai Han,Peng Zhang,Jian-jiang Jin,Peng-hui Guo 한국초전도저온학회 (구 한국초전도저온공학회) 2020 한국초전도저온공학회논문지 Vol.22 No.2

Extraction and phase transformation of iron in fine-grained complex hematite ore by suspension magnetizing roasting and magnetic separation

Shuai Yuan,Ruofeng Wang,Qi Zhang,Yanjun Li,Peng Gao 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.7

Suspension magnetizing roasting-magnetic separation technology was used to extract iron from fine-grainedcomplex hematite ore. The effect of roasting conditions on the magnetizing roasting-magnetic separation process wasstudied. In summary, a concentrate with TFe grade of 69.96% and Fe recovery of 79.02% could be obtained under conditionsof a roasting temperature of 500 oC, roasting time was 12 min, reductant concentration of 30%, and total gasflow of 200mL/min, while TFe grade of final tailings was 5.66%. The phase composition and X-ray photoelectronspectroscopy analysis showed that hematite in the sample was transformed into magnetite during suspension magnetizationroasting. After roasting, the proportion of Fe content in the phase of the magnetite increased from 5.91% inroasting feed to 97.96% in the roasting product. Transmission electron microscopy results also confirmed that hematitewas transformed into magnetite with spinel structure, and the newly formed magnetite had good crystallinity. Scanning electron microscopy and BET analysis showed that roasting could increase the specific surface area, total porevolume, and porosity of the roasted product, which would strengthen the internal diffusion of CO and CO2 in the particles,to improve the reduction rate of hematite. The loose internal structure of roasted particles led to the decrease ofmechanical properties, which was conducive to improving the subsequent grinding efficiency.