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| 1 | Influence of pump noise on the health of fish in a large pumping station显示文摘The axial flow pump,characteristic of a large flow,is widely used in pumping stations of hydraulic engineering.However,the internal noise of the axial-flow pump of a high sound pressure level is notable,with a great influence on the fishing livelihood.At present,the studies of the impact of the noise on fish are mainly focused on the explosion,the offshore wind power plant,the ship and other fields,with little attention on the noise generated by the pumping station.This paper applies the combination of the computational fluid dynamics and the Actran to study the sound pressure level distribution in the high-noise area inside the axial-flow pump and the noise distribution in the downstream areas of the pumping station.Extensive comparisons are made of the hearing threshold and the hearing damage threshold of fish,and it is revealed that the noise inside the axial-flow pump exceeds the hearing damage threshold of fish,which could lead to the hearing damage of over-pumped fish.Further,the noises emitted from the pumping station to the downstream are beyond the fish hearing threshold and will also have a significant impact on the fish around the pumping station.This study can provide a reference for studying the impact of the noise generated by various large-scale water transfer projects on fish. | Fan Zhang Lu-feng Zhu Xiao-tao Shi Ke Chen Desmond Appiah Shou-qi Yuan Jin-feng Zhang | 2022 | Journal of Hydrodynamics2022，34，3： | 5 |
| 2 | Mapping aboveground biomass and its prediction uncertainty using LiDAR and field data, accounting for tree-level allometric and LiDAR model errors显示文摘Background: The increasing availability of remotely sensed data has recently challenged the traditional way of performing forest inventories, and induced an interest in model-based inference. Like traditional design-based inference, model-based inference allows for regional estimates of totals and means, but in addition for wall-to-wall mapping of forest characteristics. Recently Light Detection and Ranging(LiDAR)-based maps of forest attributes have been developed in many countries and been well received by users due to their accurate spatial representation of forest resources. However, the correspondence between such mapping and model-based inference is seldom appreciated. In this study we applied hierarchical model-based inference to produce aboveground biomass maps as well as maps of the corresponding prediction uncertainties with the same spatial resolution. Further, an estimator of mean biomass at regional level, and its uncertainty, was developed to demonstrate how mapping and regional level assessment can be combined within the framework of model-based inference.Results: Through a new version of hierarchical model-based estimation, allowing models to be nonlinear, we accounted for uncertainties in both the individual tree-level biomass models and the models linking plot level biomass predictions with LiDAR metrics. In a 5005 km2 large study area in south-central Sweden the predicted aboveground biomass at the level of 18 m×18 m map units was found to range between 9 and 447 Mg·ha^-1. The corresponding root mean square errors ranged between 10 and 162 Mg·ha^-1. For the entire study region, the mean aboveground biomass was 55 Mg·ha^-1 and the corresponding relative root mean square error 8%. At this level 75%of the mean square error was due to the uncertainty associated with tree-level models.Conclusions: Through the proposed method it is possible to link mapping and estimation within the framework of model-based inference. Uncertainties in both tree-level biomass models and models linking plot level biomass with LiDAR data are accounted for, both for the uncertainty maps and the overall estimates. The development of hierarchical model-based inference to handle nonlinear models was an important prerequisite for the study. | Svetlana Saarela AndréWästlund Emma Holmström Alex Appiah Mensah Sören Holm Mats Nilsson Jonas Fridman Göran Ståhl | 2020 | Forest Ecosystems2020，7，3： | 3 |
| 3 | 瑞典南部Ostad区私有林多目标森林经营中期规划显示文摘【目的】根据瑞典私有林多目标经营的主要做法,对瑞典南部Ostad区进行为期10年的中期森林经营规划,以期实现木材收获和生态保护的双重目标。【方法】规划包括样地调查、Prod Mod生长预测、结果分析和计划制定。调查开展的时间为2017年10—12月,调查地点为Ostad区全区206. 27 hm^2的89个小班。【结果】根据规划,截至2027年共有15个小班、2 136. 40 m3的蓄积需要间伐,净收入为278 480. 80瑞典克朗; 33个小班、15 497. 00 m3的蓄积需要进行皆伐收获,净收入为1 481 695 838. 00瑞典克朗; 27个小班、45. 39 hm^2的面积需要进行更新,共花费1 804 742. 88瑞典克朗; 9个小班、13. 75hm^2的面积需要抚育,共花费18 956. 00瑞典克朗; 22. 87 hm^2的森林面积被增设为生态保护区范围。【结论】截至2027年,Ostad区将有170. 88 hm^2的面积作为用材林,35. 39 hm^2的森林面积作为生态保护区,总收益为14. 80亿瑞典克朗,净现值为12. 19亿瑞典克朗。在本次规划中,10年间收获量小于生长量,实现了可持续的基本收获目标;规划期末林分合理的年龄分布确保了稳定的年收入,扩大的生态保护区面积为区域内的动植物保护提供了重要场所。规划基本达到了木材收获与生态保护的双重目标。此外,规划仍存在一些不确定因素可能会对经营结果产生影响,如自然灾害、市场波动和气候变化,经分析,本规划将通过提高收益和调整经营树种来应对这些不确定因素。 | 任文子 王新杰 Alex Appiah Mensah | 2019 | 北京林业大学学报2019，41，2： | 3 |
| 4 | A decomposition method of vortex identification and its application in side channel pumps显示文摘This research utilizes theΩvortex identification method to address the turbulent flows in a single-stage side channel pump,to comprehensively characterize the three types of dynamic vortex structures classified based on directions.Premised on the Galilean invariance,the work employs coordinate rotation and transformation.Thus,the indistinguishable 3-D vortex can be simplified to 2-D vortex on typical research planes.When juxtaposing the overall performance,it was revealed that a diversity of areas with high values yielded enhanced reflection of the vortex intensity,as measured by velocity distribution.The axial vortex structure with high intensity exists at the outer radius under all conditions largely.While the longitudinal vortex usually shows high intensity between the middle and outer radius.Simultaneously,the radial vortex is more likely to be at the inner radius near the suction face.Finally,this paper introduces a specific valueξ,which represents the ratio of decomposition to the total of the manifestation of the fluid rotational pattern.From the fluctuation and mean value,it can be realized that the development of the specific vortex in three directions at different positions.For example,the specific valueξ2 refers to the typical longitudinal vortex as dynamic vortex are almost from 20%to 50%,which illustrates that the longitudinal vortex only occupies a minor percentage in the total vortex.This phenomenon is one of the main reasons for the low efficiency.The present work could provide some suggestions and references for in-depth studies in fluid engineering with intense swirling flows. | Ke Chen Fan Zhang Yu-jian Fang Desmond Appiah Shou-qi Yuan Feng Hong | 2022 | Journal of Hydrodynamics2022，34，6： | 2 |
| 5 | Extradural spinal cavernous haemangioma:case report and review of the literature显示文摘 | Appiah GA Knuckey NW Robbins PD | | 0，，02： | 1 |
| 6 | Numerical investigation on self-priming process of self-priming pump显示文摘In order to investigate the self-priming process of the self-priming pump,an unsteady simulation was conducted where the Navier-Stokes equations were used with the Lagrangian-Eularian mo-del.In course of this investigation,the volume fractions,pressure distribution and self-priming time were carried out.By analyzing the volume,velocity and pressure distribution of the gas-liquid two-phase flow at different time,the two-phase content via the variation law of the two-phase flow in the pump was carried out.By monitoring and analyzing the gas-liquid flow at the outlet of the pump,the self-priming time and crucial periods were given.Two phenomena were mainly characterized by the self-priming process such as the gas-liquid mixing and separation,which occur in the early stage of self-priming process.During that period the gas-liquid mixing clouds appear on the outer edge of the impeller,and the instantaneous void fraction at the inlet and outlet of the impeller decreases obviously.It was also established from the transient study that the gas has a major influence on the hydraulic performance of the pump at the early stage of operation.To increase the usage of self-priming pump and to also understand the energy conversion of the pump,it is very essential to investigate and establish the basic working principle of the self-priming pump. | FALL Ibra PAN Zhongyong ZHANG Desheng DESMOND Appiah ALI Asad YANG Bo | 2020 | 排灌机械工程学报2020，38，11： | 1 |
| 7 | ( 1998 ), Market Orientation and Performanee: Empirical Tests in a Transition Economy? 显示文摘 | Appiah - Adu K | 1998 | Journal of Strategic Marketing1998，6，： | 1 |
| 8 | Groundwater management in drought-prone areas of Africa 显示文摘 | Mtembezeka P Andrews A J Appiah S O | 1997 | Water Resources Development1997，13，2： | 1 |
| 9 | Surgical treatment of Cesarean scar ectopic pregnancy:efficacy and safety of ultrasound-guided suction curettage显示文摘 | Jurkovic D Knez J Appiah A | 2016 | Ultrasound Obstet Gynecol2016，47，4： | 1 |
| 10 | Thick Translation显示文摘 | Appiah K A | | 0，，04： | 1 |
| 11 | Thick translation显示文摘 | Appiah K | | 0，，16： | 1 |
| 12 | Thick translation显示文摘 | Appiah K | 1993 | Callaloo1993，16，4： | 1 |
| 13 | Improved production of adenovirus vectors expressing apoptotie transgenes显示文摘 | Bruder J T Appiah A Kirkman W M | 2000 | Hum Gene Ther2000，，11： | 1 |
| 14 | Can family or replacement blood donors become regular volunteer donors显示文摘 | Kwame A M Achina G Appiah R | 2014 | Transfusion2014，54，1： | 1 |
| 15 | A spatially distributed model for foreground segmentation 显示文摘 | Dickinson P Hnnter A Appiah K | 2009 | Image and Vision Computing2009，27，9： | 1 |
| 16 | Comparative study on experiments and simulation of blended cathode active materials for lithium ion batteries显示文摘 | APPIAH W A PARK J VAN KHUE L | 2016 | Electrochimica Acta2016，187，： | 1 |
| 17 | Extradural spinal cavernous haemangioma: case report and review of the literature 显示文摘 | Appiah GA Knuckey NW Robbins PD | 2001 | J Clin Neurosei2001，8，2： | 1 |
| 18 | Texturing of polycrystalline SiC films on graphitic carbon in laminated composites grown by forced-flow chemical vapor infiltration显示文摘 | Appiah K A Wang Z L Lackey W J | 2000 | Thin Solid Films2000，371，： | 1 |
| 19 | Hemodialysis acutely improves hepatic CYP3A4 metabolic activity显示文摘 | Nolin TD Appiah K Kendrick SA | 2006 | J Am Soc Nephrol2006，17，9： | 1 |
| 20 | Improved production of adenovirus vectors expressing apoptotic transgenes显示文摘 | Bruder J T Appiah A Kirkman W M | 2000 | Hum Gene Ther2000，，11： | 1 |
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