Optimal design of culling compensation policy under the African swine fever——Based on simulations of typical pig farms in China

This paper aims to optimize the culling compensation policy from a micro perspective through scenario simulation.Based on an investigation of 273 pig farms in eight regions,four typical pig farms were constructed according to farm size and breeding mode,representing the swine producers in China.Besides,a decision objective function of pig farms facing suspected African swine fever(ASF)outbreaks was constructed.This study used a mathematical programming model to design and simulate scenarios based on compensation standards and local implementation levels,aiming to incentivize pig farms to report epidemics.The results show that the optimal decisions on epidemic reports differed among typical farms and by herd daily age.The results suggest the following adjustments for optimizing culling compensation policies:(1)to set culling compensation standards based on the market value and(2)to maintain a high level of epidemic surveillance capability in the animal husbandry and veterinary sector.

3D Model Occlusion Culling Optimization Method Based on WebGPU Computing Pipeline

Nowadays,Web browsers have become an important carrier of 3D model visualization because of their convenience and portability.During the process of large-scale 3D model visualization based on Web scenes with the problems of slow rendering speed and low FPS(Frames Per Second),occlusion culling,as an important method for rendering optimization,can remove most of the occluded objects and improve rendering efficiency.The traditional occlusion culling algorithm(TOCA)is calculated by traversing all objects in the scene,which involves a large amount of repeated calculation and time consumption.To advance the rendering process and enhance rendering efficiency,this paper proposes an occlusion culling with three different optimization methods based on the WebGPU Computing Pipeline.Firstly,for the problem of large amounts of repeated calculation processes in TOCA,these units are moved from the CPU to the GPU for parallel computing,thereby accelerating the calculation of the Potential Visible Sets(PVS);Then,for the huge overhead of creating pipeline caused by too many 3D models in a certain scene,the Breaking Occlusion Culling Algorithm(BOCA)is introduced,which removes some nodes according to building a Hierarchical Bounding Volume(BVH)scene tree to reduce the overhead of creating pipelines;After that,the structure of the scene tree is transmitted to the GPU in the order of depth-first traversal and finally,the PVS is obtained by parallel computing.In the experiments,3D geological models with five different scales from 1:5,000 to 1:500,000 are used for testing.The results show that the proposed methods can reduce the time overhead of repeated calculation caused by the computing pipeline creation and scene tree recursive traversal in the occlusion culling algorithm effectively,with 97%rendering efficiency improvement compared with BOCA,thereby accelerating the rendering process on Web browsers.

Impact of Vaccination and Culling on Controlling Foot and Mouth Disease: A Mathematical Modelling Approach

Foot and mouth disease (FMD) is a major threat, not only to countries whose economies rely on agricultural exports, but also to industrialized countries that maintain a healthy domestic livestock industry by eliminating major infectious diseases from their livestock populations. In this paper a simple mathematical model is formulated and comprehensively analyzed to assess the impact of vaccination and culling on controlling FMD. Overally the study demonstrates that vaccination and culling are essential on controlling FMD if they are all implemented. Furthermore the study illustrates that culling latently infected (early detection of infected animals) is extremely important on controlling FMD dynamics.

Analysis of the lifetime and culling reasons for AI boars

Background: The aim of the study was to analyze the lifetime and culling reasons for boars used in insemination centers(AI centers).Methods: The data collected from 355 culled boars from 1998 to 2013 included: age at start of semen collection,boar herd life, culling reason, daily gain and lean meat content, and number of ejaculates not meeting sales requirements after dilution. Culling reasons were divided into 7 groups: low semen value(LSV), low or lack of libido(LL), leg problems(LP), infectious diseases(ID), old age(OA), reduced demand for semen from the given boar(RD),and others(OT).Results: The most common culling reasons for boars were LSV(23.7%) and RD(22.5%). It was observed that the lowest daily gains were noted in boars culled due to OA. Boars culled due to OA and RD were maintained in production for the longest time(over 1000 d), for LSV and ID retention was about 700 d, and due to LL below 400 d. The survival probability was over 0.9 until 1.5 yr, and just over 0.2 until 4 yr. The highest relative frequency was observed in the 36 ^(th) and 42 ^(nd) mo of life(over 16%). Hazard risk analysis revealed a more than 10 times higher risk of culling in the case of LL, ID or OT, in comparison to OA.Conclusions: The results can be used as a direct point of reference for the identification of emerging problems in AI boar exploitation and the development of an appropriate culling policy in AI centers.

cull小议

近来有关禽流感的报道中经常用Ncun这个词，词典给cull下的定义是“为了减少或者限制数量，剔除动物，尤其是那些弱者”。cull这个词起源于拉丁语，然后进入法语，成了colligere，意思是“绑在一起”；从法语进入了英语，成了cull，原义是“选择植物或者砍伐树”，引申为“

Visibility Culling Algorithm with Hierarchical Adaptive Bounding Setting

Hierarchical adaptive bounding setting （HABS）, a novel algorithm to reduce potentially visible set, is designed to be Used for various geometry shape character in complex simulation scene to greatly improve geometry spatial storage precision. A spatial hierarchy tree is used to represent the topology of the model, and then the visibility geometry set from the viewpoint is determined by processing the hierarchy tree and frustum detection. In this process, HABS improves the viewpoint-to-region visibility detection efficiently. The algorithm is well-suited for complex models whose shape characters are various.

Occlusion Culling Algorithm Using Prefetching and Adaptive Level of Detail Techni

A novel approach that integrates occlusion culling within the view-dependent rendering framework is proposed. The algorithm uses the prioritized-layered projection（PLP） algorithm to occlude those obscured objects, and uses an approximate visibility technique to accurately and efficiently determine which objects will be visible in the coming future and prefetch those objects from disk before they are rendered, view-dependent rendering technique provides the ability to change level of detail over the surface seamlessly and smoothly in real-time according to cell solidity value.

Productive Performance of Double-Muscled Piemontese Culled Cows in Finishing Period

The aims of the study were to evaluate productive performances and environmental impact of double-muscled Piemontese culled cows. In two trials, 39 Piemontese culled cows aged from 46 to 176 mon were fattened using diets commonly applied in farm conditions. The animals were weighed at the beginning and end of the trials. Concentrate and hay intake were recorded daily. After slaughtering, meat, fat and bone yields were recorded and dressing percentage was calculated. The backward linear regression model was employed for statistical analysis. Results showed average body weight （ABW） of cows as （556.97± 55.99） kg and relatively low dry matter intake （DMI） [（9.17± 0.35） kg d^-1] during the fattening period. The ratio between DMI and ABW, i.e., ratio between intake and weight （RIW）, （1.66±0.18）% was negatively influenced by initial body weight （IBW） and duration of finishing period （D）, but age had no effect on RIW. Average daily gain （ADG） was relatively low [（0.55 ±0.21） kg d^-1, and was negatively correlated with IBW and D, which implied that lower IBW and shorter D could have higher ADG and vice versa. The dressing percentage （DP） was （59.80± 1.83）% and the carcass red meat yield （MY） was （75.17±3.10）%. Nevertheless, N efficiency was very low [（4.35 ± 1.76）%], which must be considered in relation to environmental protection so both animal requirements and a well balanced diet need more attention. In conclusion when Piemontese cows will be culled and fattened, IBW and D should be considered carefully in order to get a reasonable ADG and N efficiency to guarantee productive benefits and environmental protection at the same time.

Spatiotemporal changes in antlerless proportion of culled Sika deer in relation to deer density

Population management of herbivores is widely applied to decrease damage to forests in the northern hemisphere. Culling more antlerless deer, including females and fawns, is an effective means of reducing the population and helps to improve management efficiency. To increase the efficiency of antlerless-biased culling, we assessed the spatiotemporal distribution of the antlerless ratio in culled sika deer (Cervus nippon) in relation to population density. We hypothesized that the antlerless ratio is higher at the center of the distribution than at the margins of the deer’s range, because dispersal processes differ according to sex and age: Young male deer first disperse into an unoccupied area, and then males may become established in the new area for approximately 10–15 years before the number of females increases. A statistical model revealed spatiotemporal changes in the antlerless ratio of culled sika deer. The change in the ratio basically fit the density distribution of the deer, which was estimated independently on the basis of fecal pellet count surveys. The antlerless ratio estimated from the model increased asymptotically as deer density rose. The results support our hypothesis and suggest that antlerless sika deer will be more easily culled at the center rather than at the margins of the distribution range. These findings should help to increase the efficiency of managing the deer via antlerless-biased culling.

Physical Conditions of Cull Sows Associated with On-Farm Production Records

Cull sow physical conditions were associated with on-farm production records. Sows (923) within one integrated U.S. production system were evaluated at two harvest facilities. Physical conditions evaluated at harvest were analyzed by parity, culling code and production measures. Farm culling codes were categorized into poor body condition (BC), old age (G), lameness (L), other (O), poor litter performance (P) and reproductive failure (R). Production measures included lifetime pigs born alive (LPBA), pigs born alive in the last litter (PBALL), pigs per sow per year (PSY) and weaning to culling interval. The L culling code had a greater (P < 0.05) prevalence of cracked hooves when compared to the other five culling codes (30.9% vs. 18.7%). Sows without front cracked hooves tended (P = 0.07) to have greater PSY (0.80) when compared to sows having front cracked hooves. Females without rear digital overgrowth had more (P < 0.05) PBALL (0.54) and tended (P = 0.06) to have increased PSY (0.80) when compared to sows with rear digital overgrowth. Sows without shoulder lesions had greater (P < 0.05) LPBA (2.01) when compared to sows with shoulder lesions. Regression coefficient estimates for percent lung lesion involvement were positive and tended (P < 0.10) to be different from zero for LPBA (0.06) and PSY (0.03). Females with severe teeth wear tended (P ≤ 0.10) to have fewer LPBA (1.36), PBALL (0.45) and had fewer (P < 0.01) PSY (1.10) when compared to sows without severe teeth wear. Sows culled for BC and L had lower (P < 0.01) backfat when compared to sows from the other four culling codes (1.83 and 2.04 cm vs. 2.47 to 2.85 cm, respectively). Multiple cull sow physical conditions evaluated at harvest had associations with on-farm reproductive measures.

人乳头瘤病毒16E7和CulL2依赖蛋白对APOBEC3A蛋白表达及子宫颈细胞迁徙能力的影响

人乳头瘤病毒(Human papillomavirus,HPV)16 E7基因编码多功能磷酸蛋白,其功能和结构均类似腺病毒,HPV 16 E7可与激活的致癌基因结合,促进肿瘤进展。但是HPV 16 E7对子宫颈细胞迁移的影响和机制尚不清楚。因此本研究探究了HPV16 E7和CulL2依赖蛋白对APOBEC3A蛋白表达及子宫颈细胞迁徙能力的影响。随机选择60名年龄在21～55岁间的妇女,分别设置空白对照组(B组)、患有人乳头瘤细胞组(P组)、添加CulL2依赖蛋白组(C组),采用流式荧光杂交法和第二代杂交捕获实验(hc2)检测其子宫颈脱落细胞,进行细胞培养,采用Transwell法检测细胞数,重组质粒DNA分析基因克隆的完整性,代谢标记细胞,进行过氧化氢酶(catalase,CAT)分析。采用实时荧光定量PCR法对CulL2和APOBEC3A基因水平进行评估测定,免疫印迹(Western Blot,WB)检测相关蛋白表达。与B组相比,P组细胞穿透基质胶的细胞数增多,即迁徙能力提高,重组质粒转染后,C组细胞穿透基质胶的细胞数亦明显增多,但增多幅度不如P组,即迁徙能力有所增强(P<0.05)。高风险HPV蛋白E7可上调细胞中APOBEC3A蛋白的表达。APOBEC3A和HPV16 E7与CulL2相互作用,表明在HPV感染期间形成的E7可调节细胞中的APOBEC3A蛋白的水平。反转录PCR(Reverse transcription-PCR,RT-PCR)结果显示,与B组比较,P组细胞基因表达增加,C组细胞中CulL2和APOBEC3A基因的mRNA表达水平明显减少(P<0.05)。本研究发现HPV16 E7和CulL2依赖蛋白可影响APOBEC3A蛋白表达,并且促进子宫颈细胞的迁徙能力。

基于深度学习无人机影像道路实景三维修复

针对基于无人机倾斜影像实景三维重建中,移动目标对道路实景三维重建造成几何变形和纹理失真的问题,提出一种基于深度学习的无人机影像道路实景三维修复方法。首先,通过添加注意力机制的深度学习网络模型YOLOv8对影像中目标进行检测;其次,在得到影像对应目标标记的基础上,根据已生成三维Mesh模型中各三角面在可视影像集合中的投影位置,结合影像所标记目标的对应范围,统计各三角面的类别信息以此判定移动目标;最后,利用移动目标判定结果对移动目标造成的三维模型几何变形及纹理错误进行修复,实现道路实景三维重建。结果表明:改进的网络模型较YOLOv4、YOLOv5和YOLOv8模型,平均精度(mAP)值平均提升10.82%,移动目标判定准确率达97.43%。与流行国外商业软件相比,所提方法重建修复效果更佳,自动化程度更高。

基于Web3D的车间可视化系统设计与实现

针对当前三维可视化系统中存在的渲染速度慢、渲染效率低等问题,引入视锥体剔除渲染算法,基于Web3D技术设计了可视化车间系统。该系统采用B/S框架,利用Three.js技术实现场景的3D加载,实现了在浏览器上进行虚拟化仿真模拟。使用八叉树和轴对称包围盒的视锥体剔除渲染算法,提高了三维场景的渲染速度。并通过综合车间的实际验证,实现了车间设备的工作状态实时监控,生产数据展示更加立体、直观,有效提升了车间可视化系统运行效率和交互性能,满足了现代化车间的管理需求。

基于多策略融合灰狼算法的移动机器人路径规划

针对标准灰狼算法(GWO)在解决移动机器人路径规划问题时存在初始参数依赖性强、缺乏多样性及易陷入局部极值的缺陷,提出一种基于多策略融合灰狼算法(LTGWO)。首先运用精英化思想将Logistic-Tent复合混沌映射与反向学习结合,优化灰狼种群分布序列;然后引入sigmoid函数修改收敛因子a,平衡算法全局探索与局部开发能力,并改进控制参数C以更好地拟合灰狼实际捕猎过程;最后加入随适应度值变化的比例权重,提高灰狼个体搜索能力,同时采用种群淘汰策略,淘汰适应度值差的个体,促进种群进化。选用3组不同的栅格地图进行实验,实验结果表明:由LTGWO算法生成的平均路径长度、路径长度标准差都优于对比算法。

Unwanted and unintended effects of culling: A case for ecologically-based rodent management

In this study, the ecological effects of culling programs are considered in the context of rodent pest management.Despite the escalation of rodent problems globally, over the past quarter of a century there have not been many newdevelopments in culling programs directed at managing these populations. There is a strong reliance on broad scaleuse of chemical rodenticides or other lethal methods of control. The ecological consequences of culling programsbased on chemical rodenticides and bounty systems are considered. Although rodents cause tremendous economichardship to people on a continental scale, usually less than 10% of species cause substantial impacts. Indeed, manyspecies of rodent provide important “ecological services” and, given that culling programs rarely distinguishbetween rodent species, often the non-pest rodents are at grave risk. Rodent control is conducted with littleappreciation of what proportion of the population would need to be culled for a significant reduction in economicdamage. In Indonesian rice fields, once rodent densities are high then a reduction in yield loss from 30% to 15%would require more than 75% of the population to be culled;a reduction to less than 5% yield loss would requiremore than a 95% cull. The negative ecological consequences of culling can be better managed if the method isspecifically tailored to the species that need to be managed. A greater emphasis on ecologically-based rodentmanagement would assist markedly in reducing the unwanted and unintended effects of culling.

芝麻酱感官词典的开发和建立

为建立芝麻酱的感官词典,依据GB/T 16861-1997《感官分析通过多元分析方法鉴定和选择用于建立感官剖面的描述词》产生芝麻酱的感官描述词,以几何平均值法分析删减描述词以制作芝麻酱感官风味轮,以相关性分析和主成分分析提炼关键性描述词,对关键性描述词添加定义、寻找参比样并进行强度赋值以形成芝麻酱关键性感官属性定量描述词汇表。结果显示,最终提炼20个关键性描述词(7个气味描述词,8个风味描述词,3个口感描述词,2个外观描述词)对芝麻酱感官特征进行定量描述分析。通过芝麻酱感官词典获得了不同芝麻酱的感官属性特征,且不同产地和焙炒条件芝麻酱的感官特征存在差异,这验证了芝麻酱感官词典的有效性。芝麻酱感官词典的开发为芝麻酱感官评价体系的建立提供了基础。

基于Web的大规模三维空间模型高效可视化关键技术

在网络环境下客户端对大规模的三维空间模型进行可视化时仍存在着渲染时间长、计算量大等诸多问题,表现为模型遮挡剔除计算效率低、模型数据传输效率低以及渲染不同模型时存在性能和质量不平衡问题等方面。针对上述问题,提出了针对不同的空间模型剔除粒度的优化选择策略、基于WebGPU计算管线的遮挡剔除算法和基于多线程的大规模三维空间模型数据快速调度方案,降低了离线遮挡剔除方法的预处理时间消耗,提高了模型切换的效率和场景渲染的速率。开发了基于Web的大规模三维空间模型可视化原型系统,开展了不同尺度的三维模型加载与可视化实验,结果表明,本文方法可以有效减少网络环境下大规模三维空间模型数据可视化的加载和渲染时间,增强用户体验。

Trends in in ovo sexing technologies:insights and interpretation from papers and patents

Numerous researchers and institutions have been developing in ovo sexing technologies to improve animal welfare by identifying male embryos in an early embryonic stage and disposing of them before pain perception.This review gives a complete overview of the technological approaches reported in papers and patents by performing a thorough search using Web of Science and Patstat/Espacenet databases for papers and patents,respectively.Based on a total of 49 papers and 115 patent families reported until May 2023 worldwide,11 technology categories were defined:6 non-optical and 5 optical techniques.Every category was described for its characteristics while assessing its potential for application.Next,the dynamics of the publications of in ovo sexing techniques in both paper and patent fields were described through growth curves,and the interest or actual status was visualized using the number of paper citations and the actual legal status of the patents.When comparing the reported technologies in papers to those in patents,scientific gaps were observed,as some of the patented technologies were not reported in the scientific literature,e.g.,ion mobility and mass spectrometry approaches.Generally,more diverse approaches in all categories were found in patents,although they do require more scientific evidence through papers or industrial adoption to prove their robustness.Moreover,although there is a recent trend for non-invasive techniques,invasive methods like analyzing DNA through PCR or hormones through immunosensing are still being reported(and might continue to be)in papers and patents.It was also observed that none of the technologies complies with all the industry requirements,although 5 companies already entered the market.On the one hand,more research and harmony between consumers,industry,and governments is necessary.On the other hand,close monitoring of the market performance of the currently available techniques will offer valuable insights into the potential and expectations of in ovo sexing techniques in the poultry industry.

Causes and Effects of Stillbirths on Days Open and Cow Herd Survival in Holstein Friesian Cows

The aim of this retrospective study was to investigate the causes and the effects of stillbirth on the number of days open and cow herd survival in subsequent lactation of Holstein Friesian cows. A total of 1371 calvings from research dairy farm were used. Stillbirth in calves was defined as the death of a fetus before or during calving at full term (≥270 days of gestation) or within 24 hours after calving. During the period from January 2006 to December 2017 a percent of 95.04% of the calvings were with live calves, and 4.96% of the calvings were stillbirths. The major causes of stillbirth identified were: calving difficulty, parity of the cows, and sex of the calves at calving. A five point scale was used to assess calving difficulties, and numbers 1, 2 and 3 were considered unassisted calvings and number 4 and 5 as assisted. The twin calvings were not taken into account. Days open were measured as days from first calving to conception, and cow herd survival from first calving to culling or death. Trend test and multivariate data analysis were used. The findings revealed that primiparous cows were at higher risk of having stillbirths compared with multiparous cows. Cows that were at calving male calves were at higher risk of having stillbirths compared with cows that had female calves at calving. Also, cows with assisted calving were at higher risk of having stillbirths compared with cows with unassisted calvings. Cows with stillbirths had a increase mean of days open with 32 days. Cow herd survival was better in the cows with live calves at calving compared with the cows that had stillbirth at calvings.

基于热红外与可见光图像融合的生菜水分胁迫指数模型研究

为了准确提取作物冠层温度,监测作物水分亏缺状态,以不同水分处理的生菜为研究对象,分别利用手持式热像仪和佳能相机获取生菜的热红外和可见光图像,计算生菜冠层可见光图像与热红外图像的仿射变换参数,并进行配准融合,以获取生菜冠层区域的热红外图像,而后计算不同处理下的基于冠层温度的水分胁迫指数(Crop Water Stress Index, CWSI)与日蒸散量(Evapotranspiration,ET),分析不同灌溉处理下CWSI同ET的相关关系来监测生菜水分亏缺程度。结果表明,基于仿射变换的热红外目标提取方法可以实现生菜冠层的准确提取,剔除背景后生菜冠层的平均温度值由20.25℃下降至19.25℃。不同水分处理下的生菜热红外冠层的CWSI值展示出明显的差异,且CWSI与ET呈显著负相关,当CWSI越大,ET越小,表明CWSI可以应用在生菜水分胁迫状态监测,能够很好的反应土壤水分含量变化状况。