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排序方式: 共有73条查询结果,搜索用时 15 毫秒
1.
Shi  Jiawen  Li  Hong  Zhou  Jiale  Pang  Zhicheng  Wang  Chiyu 《The Journal of supercomputing》2022,78(4):4759-4778

The traditional emotion–cause extraction task needs to give the exact emotion annotation contained in the document before extracting the cause. Different from this, the emotion–cause pair extraction (ECPE) task, which aims to extract emotion–cause pairs with causal relationships directly from the document, is a task proposed in the natural language processing field recently. At present, the task of ECPE is divided into two steps: emotion annotations and cause clause extraction, emotion–cause clause pair combining and filtering. In this article, we optimize these two steps. On the one hand, in the first step of ECPE, a mutual assistance single-task model proposed by us is used to replace the original multi-task model. On the other hand, the position information of the clause is added as an additional feature in the second step of ECPE. Furthermore, based on different levels of semantic features, we design three filtering models and explore their performance on ECPE tasks. The experimental results on the benchmark corpus show that our approach can make the ECPE task achieve better performance. Compared with the referenced method, F1-score is increased by 5.3%. Moreover, these optimization strategies improve the subtasks contained in ECPE to varying degrees.

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2.
刘驰宇 《中外建筑》2016,(4):126-129
目前伴随着经济的快速发展,交通量也再与日俱增,这给现有的交通设施造成了很大的压力,这种形势下,无论是高速公路还是其他低等级公路,都面临着改扩建的情形。但同时由于受到新增占地与建设成本的限制,更多的道路采取了加宽改造的方式,当遇到旧路中的桥梁需要加宽改造时,则需要从桥梁整体稳定性,受力特征等多方面考虑加宽改造形式的适宜性。  相似文献   
3.
Diabetic ulcer is the most common kind of chronic wound worldwide. Though great efforts have been devoted, diabetic ulcer still remains as a challenge that requires constant monitoring and management. In this work, a multifunctional zwitterionic hydrogel is developed to simultaneously detect two fluctuant wound parameters, pH and glucose level, to monitor the diabetic wound status. A pH indicator dye (phenol red) and two glucose sensing enzymes, glucose oxidase (GOx) and horseradish peroxidase (HRP), are encapsulated in the anti‐biofouling and biocompatible zwitterionic poly‐carboxybetaine (PCB) hydrogel matrix. The visible images are collected by a smartphone and transformed into RGB signals to quantify the wound parameters. Results show that the activity and stability of both two enzymes are improved within PCB hydrogel, and the Kcat/Km value of PCB‐HRP is ≈5.5 fold of free HRP in artificial wound exudate. This novel wound dressing can successfully monitor the pH range of 4–8 and glucose level of 0.1–10 × 10?3 m . Meanwhile, it also provides a moist healing environment that can promote diabetic wound healing. This multifunctional wound dressing may open vistas in chronic wound management and guide the diabetes treatment in clinical applications.  相似文献   
4.
射流流量计的仿真与试验研究   总被引:5,自引:0,他引:5  
以流场仿真为基础,设计射流流量计内部流道结构,研究射流流量计内部流场的速度分布和压力分布,并研究射流附壁诱发流体交替振荡的机理,提出主射流的偏转过程实际上是两个共同作用于主射流的涡流强弱交替的过程。在此基础上,以仿真模型优化射流流量计,通过试验验证射流振荡的效果以及管道流速与流体振动频率之间的特性关系。并设计出计量范围0.55~6.50 m/s(气体介质)、精度等级高于2级的射流传感器,为射流流量计的结构改进和优化设计提供了有效的途径。  相似文献   
5.
通过对美国北卡罗来纳州三角研究区建立,建设,发展过程的描述,归纳和总结其作为政府背景、各界合作、产学互动以及构筑独特园区风貌的经验和特征.  相似文献   
6.
针对坡角为18.4°的典型双坡低矮建筑屋面局部风压非高斯特性,在A、B、C 3类地貌下展开了风洞试验研究。主要研究了典型测点风压系数时程概率密度的分布特征,分析了不同地貌类别和不同风向角下风压非高斯区的分布规律,探讨了风压非高斯特性与屋面流场的关系。结果表明:斜风向下,相比Gaussian分布和Lognormal分布,GEV分布和Gamma分布能更好地拟合屋面易损区的风压系数概率分布,但当偏度与峰度较大时,对长拖尾区域的拟合效果较差;地貌类别和风向角对低矮建筑屋面风压非高斯区分布影响显著,斜风向下风压高斯区沿来流方向分成三股区域,且随着地貌类别变化而沿来流方向移动;屋面风压非高斯特性与风压空间互相关性系数呈正相关。  相似文献   
7.
Semiconductor lasers with monolithically integrated ring cavities exceeding 1 cm in perimeter were fabricated and characterized optically and electrically. Directional switching was observed, influenced by S-section seeding of unidirectional operation. The lasing threshold was identified by differential current-voltage measurements, which are also shown to be useful in monitoring directional switching. Mode beating was observed at three radio-frequency bands: 7.6, 15.2, and 22.9 GHz.  相似文献   
8.
针对苎麻纤维刚度大、成纱毛羽过多、经典四组分嵌入纺操作不便等技术问题,采用简化嵌入纺组分、加捻成纱段增设海绵接触纱条装置,提出接触式简易嵌入纺的纺纱方法。分析了简易嵌入纺、干态接触式简易嵌入纺、湿态接触式简易嵌入纺的成纱机制,并改造传统环锭纺纱小样机进行实验。对比分析各种简易嵌入纺技术的成纱性能与品质。结果表明:与简易嵌入纺、干态接触式简易嵌入纺相比,采用湿态接触式简易嵌入纺技术,可在线柔化苎麻纤维,利于纤维间扭转抱合与弯曲包缠,纺制的纱线毛羽大幅降低,拉伸断裂强力较高,成纱品质好。  相似文献   
9.
Single‐walled carbon nanotubes (SWCNTs) are a class of 1D nanomaterials that exhibit extraordinary electrical and optical properties. However, many of their fundamental studies and practical applications are stymied by sample polydispersity. SWCNTs are synthesized in bulk with broad structural (chirality) and geometrical (length and diameter) distributions; problematically, all known post‐synthetic sorting methods rely on ultrasonication, which cuts SWCNTs into short segments (typically <1 µm). It is demonstrated that ultralong (>10 µm) SWCNTs can be efficiently separated from shorter ones through a solution‐phase “self‐sorting”. It is shown that thin‐film transistors fabricated from long semiconducting SWCNTs exhibit a carrier mobility as high as ≈90 cm2 V?1 s?1, which is ≈10 times higher than those which use shorter counterparts and well exceeds other known materials such as organic semiconducting polymers (<1 cm2 V?1 s?1), amorphous silicon (≈1 cm2 V?1 s?1), and nanocrystalline silicon (≈50 cm2 V?1 s?1). Mechanistic studies suggest that this self‐sorting is driven by the length‐dependent solution phase behavior of rigid rods. This length sorting technique shows a path to attain long‐sought ultralong, electronically pure carbon nanotube materials through scalable solution processing.  相似文献   
10.
采用两种方法分别模拟了钢闸门的两种卡阻故障,一种是施加约束的方法模拟面板与侧轨间的卡阻;另一种是在接触面设立三维非线性薄层单元的方法模拟弧形闸门铰轴的卡阻。引用某水电站弧形闸门作为算例,对这两种卡阻故障进行了数值模拟,将得到的应力结果与钢闸门在正常运行情况下的应力状态做了对比分析:其中第一种模拟方法着重分析了面板的应力,结果表明卡阻处面板有应力集中,但影响范围不大,约占面板宽度的4%;而第二种模拟方法则着重分析了支臂的应力,结果显示支臂应力的最大值增大一倍,但并未出现应力集中的情况。  相似文献   
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