Inverse Force Estimation in a New Lab Simulation Approach for Vibration Prediction of Building-Mounted Small Wind Turbine

Bo Ren 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.5

The structural vibration generated by building mounted small wind turbine was fully investigated by author. In order to achieve this, the real vibration condition of wind turbine in field was accurately simulated in Lab for research. There are some difficulty during the whole simulation process for further quantification of vibration levels. One of the main concerns was the correct estimation of the excitation or contact force at the interface between vibration source (turbine) and receiver (building or walls). However, the relevant simulation method in Lab is not available so far. In this paper, the direct measurement of force was investigated and found unsuitable. A new simulation method was proposed including solving the problem of power supply (DC electric motor used), automatic control of rotational speed of motor and indirect interface force determination. At last, the new established finite element models (FEM) was validated by experimental data with a good initial agreement.

Dynamics of Mixed Lump-Soliton Solutions According to a (2+1)-Dimensional Coupled Nonlinear Partial Differential Like Equation

Bo Ren,Zhi-Wei He,Yong-li Sun,Fu-Dong Wang 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.74 No.8

Based on the generalized bilinear operators in a prime number $p=3$, we introduce a (2+1)-dimensional coupled nonlinear partial differential like equation. By combining an exponential function with a quadratic function, an interaction between a lump wave and a one-kink soliton is generated. In addition, an interaction between a lump wave and a two-kink soliton, which is called a special rogue wave, can be obtained by adding two additional exponential functions. The dynamic properties of these interactions are depicted by selecting appropriate parameters.

Symmetry Reduction Related by Nonlocal Symmetry and Explicit Solutions for the Whitham-Broer-Kaup System

Bo Ren,Ji Lin 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.73 No.5

The nonlocal symmetry for the Whitham-Broer-Kaup (WBK) equation is obtained by the Painleve analysis. With the introduction of two auxiliary dependent variables, the nonlocal sym- metry is localized to the Lie point symmetry. The reciprocal transformation is established by the localization nonlocal symmetry procedure and can be used to construct a link between the WBK equation and the usual Burgers equation. By using the similarity reductions related with the non- local symmetry of the Burgers equation, we derive the symmetry invariant solutions for the WBK equation. Furthermore, the power-series solutions are computed by using the power-series theory.

CTE Method and Interaction Solutions for the Kadomtsev-Petviashvili Equation

Bo Ren 한국물리학회 2017 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.70 No.4

The consistent tanh expansion method is applied to the Kadomtsev-Petviashvili equation. The interaction solutions among one soliton and other types of solitary waves, such as multiple resonant soliton solutions and cnoidal waves, are explicitly given. Some special concrete interaction solutions are discussed both in analytical and graphical ways.

Distribution of nitrate and its implication for the contaminant source in groundwater of Huaibei Plain, Anhui Province

Jiazhong Qian,Lulu Wang,Yong Liu,Boren Wu,Xiaoming Wang 한국지질과학협의회 2015 Geosciences Journal Vol.19 No.3

High concentration of NO3-N in groundwater can pose risk to human’s health, thus the study of NO3-N contamination in groundwater is a very important issue related to public health. Using a typical agriculture zone, Huaibei plain in Anhui Province of China as a field site, the temporal and spatial variation of groundwater NO3-N concentration was studied using a multivariate statistical factor analysis combined with Kaiser-Meyer- Olkin method based on a hydrogeological investigation from 2005 to 2009 year. The results show: (1) The contaminant in the groundwater of Huaibei Plain in Anhui Province are serious. 10% of the shallow groundwater samples in non-rainy season of 2005 exceeds the recommended value of NO3-N by Chinese drinking water standard (≤20 mg/L), while 17.5% exceeds the recommended value (11.3 mg/L) by EC. (2) About 15% of shallow groundwater in the whole study area was polluted in 2005 with the maximum of 97.67 mg/L; Groundwater NO3-N concentration is higher in non-rainy season than in rainy season. And the NO3-N content in groundwater shows the increasing trend at all three depths sampled from 2005 to 2009 year. (3) Groundwater nitrate pollution mainly derives from anthropogenic activities in Huaibei Plain, Anhui Province. Further quantitative analysis need to be studied in the future.

Long-term organic-inorganic fertilization ensures great soil productivity and bacterial diversity after natural-to-agricultural ecosystem conversion

Weibing Xun,Zhihui Xu,Wei Li,Yi Ren,Ting Huang,Wei Ran,Boren Wang,Qirong Shen,Ruifu Zhang 한국미생물학회 2016 The journal of microbiology Vol.54 No.9

Natural ecosystems comprise the planet’s wild plant and animal resources, but large tracts of land have been converted to agroecosystems to support the demand for agricultural products. This conversion limits the number of plant species and decreases the soil biological diversity. Here we used highthroughput 16S rRNA gene sequencing to evaluate the responses of soil bacterial communities in long-term converted and fertilized red soils (a type of Ferralic Cambisol). We observed that soil bacterial diversity was strongly affected by different types of fertilization management. Oligotrophic bacterial taxa demonstrated large relative abundances in chemically fertilized soil, whereas copiotrophic bacterial taxa were found in large relative abundances in organically fertilized and fallow management soils. Only organic-inorganic fertilization exhibited the same local taxonomic and phylogenetic diversity as that of a natural ecosystem. However, the independent use of organic or inorganic fertilizer reduced local taxonomic and phylogenetic diversity and caused biotic homogenization. This study demonstrated that the homogenization of bacterial communities caused by natural-to-agricultural ecosystem conversion can be mitigated by employing rational organic-inorganic fertilization management.

Role of the Gastrocnemius Musculocutaneous with a Propeller Style Skin Flap in Knee Region Reconstruction: Indications and Pitfalls

Sapino Gianluca,Osinga Rik,Maruccia Michele,Guiotto Martino,Clauss Martin,Borens Olivier,Guillier David,di Summa Pietro Giovanni 대한성형외과학회 2023 Archives of Plastic Surgery Vol.50 No.6

Background Soft tissue reconstruction around the knee area is still an open question, particularly in persistent infections and multiple reoperations scenario. Flap coverage should guarantee joint mobility and protection, even when foreign materials are implanted. The chimeric harvesting of the musculocutaneous gastrocnemius flap, based on the sural artery perforators, can extend its applicability in soft tissue reconstruction of the upper leg, overcoming the drawbacks of the alternative pedicled flaps.Methods A multicenter retrospective study was conducted enrolling patients who underwent to a pedicled, chimeric gastrocnemius musculocutaneous–medial sural artery perforator (GM-MSAP) or lateral sural artery perforator (GM-LSAP) flap for knee coverage in total knee arthroplasty (TKA) recurrent infections and oncological or traumatic defects of the upper leg from 2018 to 2021. Outcomes evaluated were the successful soft tissue reconstruction and flap complications. Surgical timing, reconstruction planning, technique, and rehabilitation protocols were discussed.Results Twenty-one patients were included in the study. Nineteen GM-MSAPs and 2 GM-LSAPs were performed (soft tissue reconstruction in infected TKA [12], in infected hardware [4], and in oncological patients [5]). Donor site was closed primarily in 9 cases, whereas a skin graft was required in 12. Flap wound dehiscence (1), distal flap necrosis (1), distal necrosis of the skin paddle (1), and donor site infection (1) were the encountered complications. Flap reraise associated to implant exchange or extensive debridement was successful without requiring any further flap surgery.Conclusion The propeller–perforator GM-MSAP offers qualitative defect coverage and easiness of multiple flap reraise due to skin availability and its laxity.

사료의 곡류조성 ( 수수 , 수수 + 옥수수 , 옥수수 ) 이 육계 , 돼지 및 한우의 생산성에 미치는 영향

백인기(In Kee Paik),문윤영(Yun Young Moon),이종복(Jong Bok Lee),(Bruce Boren) 한국축산학회 1989 한국축산학회지 Vol.31 No.8

Effects of grain composition of feeds on the performance of broiler chickens, swine and Korean native bulls were tested. Least-cost diets formulated to be isocaloric and isonitrogenous contained one of the 3 grain sources; U.S. No. 2 Yellow Grain Sorghum, U.S. No. 3 Yellow Dent Corn, and a 50:50 combination of sorghum and corn. Broiler chickens fed sorghum+corn diet showed more weight gain(p$lt;0.05) and better feed efficiency than the birds fed either sorghum diet or corn diet. Pigs fed sorghum diet and sorghum-corn diet showed significantly more weight gain(p$lt;0.01) and more feed intake(p$lt;0.05) than those fed corn diet. Feed efficiency of the pigs fed sorghum + corn diet was highest followed by corn diet and sorghum diet but they were not significantly different. Cattle fed sorghum diet and sorghum+corn diet gained significantly (p$lt;0.05) more weight than those fed corn diet. Feed efficiency of the tattles were not significantly influenced but those fed corn diet tended to be lower than others. Overall, combination of sorghum and corn showed best results indicating synergistic effect of two grain sources and there were species differences in the response to sorghum and corn. The results of cattle expriment indicates that difference of TDN values of sorghum and corn may not as great as expected.