化工学报 ›› 2025, Vol. 76 ›› Issue (1): 266-282.DOI: 10.11949/0438-1157.20240708
收稿日期:
2024-06-24
修回日期:
2024-08-19
出版日期:
2025-01-25
发布日期:
2025-02-08
通讯作者:
卢建刚
作者简介:
杨晔(1996—),男,博士研究生,工程师,11832016@zju.edu.cn
基金资助:
Received:
2024-06-24
Revised:
2024-08-19
Online:
2025-01-25
Published:
2025-02-08
Contact:
Jiangang LU
摘要:
门尼系数的精准预测是优化橡胶混炼工艺的关键一环,有助于橡胶轮胎生产过程及时把控胶料质量。为此,提出了一种基于融合Transformer的门尼系数预测模型(fusion Transformer,Fusformer),对橡胶混炼产生的时间序列变量与静态协变量数据进行针对性建模,提取并融合各类数据特征,精确预测门尼系数。针对时间序列变量,模型引入有向图的概念,提出相对位置感知层与相对多头注意力机制,充分地捕捉时序依赖特征;针对静态协变量,模型引入门控线性单元并提出了静态特征富集模块,提取有效静态特征,最终将时序依赖特征与有效静态特征融合并输出预测值。实验利用大型橡胶轮胎企业的20万条实际采样样本测试了模型的预测性能,通过对照实验、消融分析以及参数灵敏度分析论证了模型设计的合理性。
中图分类号:
杨晔, 卢建刚. 基于融合Transformer的门尼系数预测建模研究[J]. 化工学报, 2025, 76(1): 266-282.
Ye YANG, Jiangang LU. Mooney viscosity prediction modeling based on fusion Transformer[J]. CIESC Journal, 2025, 76(1): 266-282.
算法1:所提出模型算法伪代码 |
---|
Input: 1. data:实验数据集 2. tsp(·):包含可训练参数 Θtsp的初始化时序特征处理模块 3. temporal(·):包含可训练参数 Θtem的初始化时序编码-解码框架 4. sem(·):包含可训练参数 Θsem的初始化静态特征富集模块 5. f (·):包含可训练参数 Θff的初始化全连接层 Output:门尼系数预测值 for each batch ( X, Y ) from data do 1. 将输入数据 X 分割成时间序列变量 Xts以及静态协变量 Xstatic 2. 将时间序列变量 Xts输入到时序特征处理模块计算时序特征:outtsp=tsp( Xts; Θtsp) 3. 将时序特征outtsp输入到时序编码-解码框架计算时序特征向量:outtem=temporal(outtsp; Θtem) 4. 将静态协变量 Xstatic输入到静态特征富集模块计算静态特征向量:outstatic=sem( Xstatic; Θsem) 5. 将时序特征向量outtem与静态特征向量outstatic进行拼接计算预测输入:predin=[outtem,outstatic] 6. 将预测输入输入到全连接层计算最终预测结果: Ypred=f(predin; Θff) end for |
表1 算法1
Table 1 Algorithm 1
算法1:所提出模型算法伪代码 |
---|
Input: 1. data:实验数据集 2. tsp(·):包含可训练参数 Θtsp的初始化时序特征处理模块 3. temporal(·):包含可训练参数 Θtem的初始化时序编码-解码框架 4. sem(·):包含可训练参数 Θsem的初始化静态特征富集模块 5. f (·):包含可训练参数 Θff的初始化全连接层 Output:门尼系数预测值 for each batch ( X, Y ) from data do 1. 将输入数据 X 分割成时间序列变量 Xts以及静态协变量 Xstatic 2. 将时间序列变量 Xts输入到时序特征处理模块计算时序特征:outtsp=tsp( Xts; Θtsp) 3. 将时序特征outtsp输入到时序编码-解码框架计算时序特征向量:outtem=temporal(outtsp; Θtem) 4. 将静态协变量 Xstatic输入到静态特征富集模块计算静态特征向量:outstatic=sem( Xstatic; Θsem) 5. 将时序特征向量outtem与静态特征向量outstatic进行拼接计算预测输入:predin=[outtem,outstatic] 6. 将预测输入输入到全连接层计算最终预测结果: Ypred=f(predin; Θff) end for |
字段名 | 变量类型 | 物理意义 | 备注说明 |
---|---|---|---|
Plan_Date | 静态协变量 | 生产计划日期 | YYYY/MM/DD |
Equip | 静态协变量 | 生产器械编号 | 数字格式 |
Type1 | 静态协变量 | 胶料主类别编号 | 字符串格式 |
Type2 | 静态协变量 | 胶料子类别编号 | 字符串格式 |
Done_Rtime | 静态协变量 | 排胶时间 | 单位为s |
PJ_Time | 静态协变量 | 卸料门开启时长 | 单位为s |
CB_DisTime | 静态协变量 | 加炭黑时长 | 单位为s |
Oil_DisTime | 静态协变量 | 加油时长 | 单位为s |
Mixing_Temp | 时序变量 | 实时温度 | 采样周期为1 s |
Mixing_Power | 时序变量 | 实时功率 | 采样周期为1 s |
Mixing_Press | 时序变量 | 实时压力 | 采样周期为1 s |
Mixing_Speed | 时序变量 | 实时转速 | 采样周期为1 s |
Mixing_Energy | 时序变量 | 实时能量 | 采样周期为1 s |
Item_Check | 静态协变量 | 门尼系数 | 预测目标 |
表2 数据集特征字段说明
Table 2 Description of dataset feature fields
字段名 | 变量类型 | 物理意义 | 备注说明 |
---|---|---|---|
Plan_Date | 静态协变量 | 生产计划日期 | YYYY/MM/DD |
Equip | 静态协变量 | 生产器械编号 | 数字格式 |
Type1 | 静态协变量 | 胶料主类别编号 | 字符串格式 |
Type2 | 静态协变量 | 胶料子类别编号 | 字符串格式 |
Done_Rtime | 静态协变量 | 排胶时间 | 单位为s |
PJ_Time | 静态协变量 | 卸料门开启时长 | 单位为s |
CB_DisTime | 静态协变量 | 加炭黑时长 | 单位为s |
Oil_DisTime | 静态协变量 | 加油时长 | 单位为s |
Mixing_Temp | 时序变量 | 实时温度 | 采样周期为1 s |
Mixing_Power | 时序变量 | 实时功率 | 采样周期为1 s |
Mixing_Press | 时序变量 | 实时压力 | 采样周期为1 s |
Mixing_Speed | 时序变量 | 实时转速 | 采样周期为1 s |
Mixing_Energy | 时序变量 | 实时能量 | 采样周期为1 s |
Item_Check | 静态协变量 | 门尼系数 | 预测目标 |
参数 | 搜索范围 |
---|---|
d_model | 64, 128, 256, 512 |
encoder layer num | 1, 2, 3, 4 |
decoder layer num | 1, 2, 3, 4 |
dropout | 0.01, 0.02, 0.05, 0.1, 0.2 |
batch size | 16, 32, 64, 128 |
learning rate | 1×10-3, 1×10-4, 1×10-5 |
kernel size | 1, 2, 3, 4 |
dilation | 1, 2, 3, 4 |
clip | 40, 50, 60, 70 |
epoch | 80, 100, 120, 140 |
表3 实验参数的搜索范围
Table 3 Search range for experimental parameters
参数 | 搜索范围 |
---|---|
d_model | 64, 128, 256, 512 |
encoder layer num | 1, 2, 3, 4 |
decoder layer num | 1, 2, 3, 4 |
dropout | 0.01, 0.02, 0.05, 0.1, 0.2 |
batch size | 16, 32, 64, 128 |
learning rate | 1×10-3, 1×10-4, 1×10-5 |
kernel size | 1, 2, 3, 4 |
dilation | 1, 2, 3, 4 |
clip | 40, 50, 60, 70 |
epoch | 80, 100, 120, 140 |
参数 | 数值 |
---|---|
d_model | 256 |
encoder layer num | 3 |
decoder layer num | 1 |
dropout | 0.05 |
batch size | 64 |
learning rate | 0.0001 |
kernel size | 3 |
dilation | 3 |
clip | 60 |
epoch | 120 |
表4 实验模型参数设置
Table 4 Experimental parameter settings
参数 | 数值 |
---|---|
d_model | 256 |
encoder layer num | 3 |
decoder layer num | 1 |
dropout | 0.05 |
batch size | 64 |
learning rate | 0.0001 |
kernel size | 3 |
dilation | 3 |
clip | 60 |
epoch | 120 |
性能指标 | LSTM | LightGBM | ResNet1D | Transformer | Conv-Transformer | Fusformer |
---|---|---|---|---|---|---|
RMSE | 5.1946 | 4.7689 | 4.5132 | 4.3664 | 3.3798 | |
MAE | 3.7790 | 3.6576 | 3.5434 | 3.3530 | 2.6169 | |
CORR | 0.8673 | 0.8812 | 0.8891 | 0.9115 | 0.9323 |
表5 门尼系数预测精度对比
Table 5 Comparison of Mooney viscosity prediction accuracy
性能指标 | LSTM | LightGBM | ResNet1D | Transformer | Conv-Transformer | Fusformer |
---|---|---|---|---|---|---|
RMSE | 5.1946 | 4.7689 | 4.5132 | 4.3664 | 3.3798 | |
MAE | 3.7790 | 3.6576 | 3.5434 | 3.3530 | 2.6169 | |
CORR | 0.8673 | 0.8812 | 0.8891 | 0.9115 | 0.9323 |
Ablation module | Model | RMSE | IMV | Δ |
---|---|---|---|---|
LEL | Transformer | 4.3664 | — | — |
Fusformer W/O LEL | 3.8132 | 14.51% | 0.4334 | |
Fusformer | 3.3798 | 28.99% | — | |
RPL&RMA | Transformer | 4.3664 | — | — |
Fusformer W/O RPL&RMA | 3.6656 | 19.12% | 0.2858 | |
Fusformer | 3.3798 | 28.99% | — | |
SEM | Transformer | 4.3664 | — | — |
Fusformer W/O SEM | 3.6243 | 20.47% | 0.2445 | |
Fusformer | 3.3798 | 28.99% | — | |
GLU | Transformer | 4.3664 | — | — |
Fusformer W/O GLU | 3.4562 | 26.37% | 0.0764 | |
Fusformer | 3.3798 | 28.99% | — |
表6 各模块消融实验结果对比
Table 6 Comparison of ablation experiment results for each module
Ablation module | Model | RMSE | IMV | Δ |
---|---|---|---|---|
LEL | Transformer | 4.3664 | — | — |
Fusformer W/O LEL | 3.8132 | 14.51% | 0.4334 | |
Fusformer | 3.3798 | 28.99% | — | |
RPL&RMA | Transformer | 4.3664 | — | — |
Fusformer W/O RPL&RMA | 3.6656 | 19.12% | 0.2858 | |
Fusformer | 3.3798 | 28.99% | — | |
SEM | Transformer | 4.3664 | — | — |
Fusformer W/O SEM | 3.6243 | 20.47% | 0.2445 | |
Fusformer | 3.3798 | 28.99% | — | |
GLU | Transformer | 4.3664 | — | — |
Fusformer W/O GLU | 3.4562 | 26.37% | 0.0764 | |
Fusformer | 3.3798 | 28.99% | — |
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