三羟甲基丙烷(TMP)生产及市场概况

本文介绍TMP的市场应用，比较了TMP两种主要生产工艺的特点，提出了我国TMP近期发展建议。／     

Option Approach to Search for Threshold Rice Price Toward Sustainable Paddy Field Management

This paper applies an option approach to search for the threshold rice price toward the sustainable paddy field management under rice price stochasticity. Rice price is assumed to follow geometric Brownian motion. The management model for paddy fields is a discrete stochastic dynamic programming model with binomial approximation for geometric Brownian motion, where a control variable is a decision to sustain or terminate paddy yield management. Our computational experiments indicate that an increase in rice price volatility could lower the threshold rice price for farmers to continue rice production. It is also shown that depending on the degree of rice price volatility, even under a lower price level than production costs, maintaining the management could become beneficial. Considering an option to terminate production could make the higher expected value of rice production than without it. Using 12 sets of time series data on voluntarily marketed rice produced in Hokkaido, Aomori, Iwate, Miyagi, Akita, Yamagata, Fukui, Ibaragi, Chiba, Niigata, Toyama and Nagano, the minimum threshold rice price of 6,700 Yen/60 kg was found in Chiba with the largest volatility, and the maximum of 7,250 Yen/60 kg in Ibaragi with the smallest volatility. If the market price becomes lower than the threshold rice price, some policy measures would be necessary toward sustainable paddy field management by covering the difference between them.     

证券领域行政执法与刑事司法的衔接问题研究

在我国,证券领域行政执法与刑事司法的衔接并不畅顺,大部分符合刑事追诉标准的案件仅被处以行政处罚,造成违法成本的低廉。其原因是多方面的,包括刑事与行政证明标准的差异,证据转换的困难,专业知识上的阻隔,以及监督的缺位等。建议通过推定方式转移公诉机关指控特殊类型证券犯罪的部分举证责任,减轻公诉机关的举证负担;根据不同证据的特点,完善行刑衔接证据转换规则;加强证券监管机构与公安机关、检察机关的沟通协调,建立信息共享及工作交流机制;增强规范执行力,确立有效的案件移送监督制度。     

冲击电压下特高压支柱绝缘子表面电场研究

特高压输变电工程对支柱绝缘子提出了更高的技术要求,运行中支柱绝缘子会因雷击发生污闪,而支柱绝缘子的电场、电位分布和闪络现象存在一定关系。为研究特高压支柱绝缘子表面电场分布特性,建立了1 100kV支柱绝缘子的有限元计算模型。理论分析与仿真结果表明,雷电冲击电压作用下支柱绝缘子表面电场分布随时间变化的曲线在波形上与激励源雷电波的波形相似,第一对和最后一对大小伞的电场强度较大,中间大小伞的电场强度较小,最大场强点位于金属电极下端的绝缘护套表面。     

村镇退化废弃地遥感监测方法初探

研究目的：开展村镇退化废弃地遥感监测技术分析,为村镇退化废弃地遥感快速监测奠定技术基础。研究方法：选择甘肃省白银市平川区作为研究区域,设计研究区内典型村镇退化废弃地类型,建立不同类型村镇退化废弃地的高分辨率遥感影像特征,提出利用遥感手段快速监测村镇退化废弃地的技术流程,详细描述了其技术方法,进而阐述村镇退化废弃地快速监测移动作业平台的详细功能需求。研究结果：研究区典型村镇退化废弃地在退化废弃前后的遥感影像特征和实地特征均有显著差别,本文的技术流程和方法可以服务于村镇退化废弃地的快速遥感监测。研究结论：采用遥感手段监测村镇退化废弃地在技术上是可行的。     

基于场强模型的合肥、马鞍山、芜湖三市融入长三角的现状与对策

文章首先概述了引力模型相关理论,提出经济辐射场强模型,通过模型得出合肥、马鞍山、芜湖融入长三角的客观条件辐射场强和主观条件辐射力;再以长三角15市接受上海经济辐射的辐射阈值为标准,分别总结出属于前三个层次的长三角城市并将其作为安徽三市融入长三角的主导城市进行承接;最后,根据安徽三市各自产业特点给出它们融入长三角的对策,为实现安徽省全面融入长三角经济圈奠定基础。     

When does advice impact startup performance?

Why do some entrepreneurs thrive while others fail? We explore whether the advice entrepreneurs receive about managing their employees influences their startup's performance. We conducted a randomized field experiment in India with 100 high-growth technology firms whose founders received in-person advice from other entrepreneurs who varied in their managerial style. We find that entrepreneurs who received advice from peers with a formal approach to managing people—instituting regular meetings, setting goals consistently, and providing frequent feedback to employees—grew 28% larger and were 10 percentage points less likely to fail than those who got advice from peers with an informal approach to managing people, 2 years after our intervention. Entrepreneurs with MBAs or accelerator experience did not respond to this intervention, suggesting that formal training can limit the spread of peer advice.     

国内外社会资本与旅游研究文献综述

社会资本包含集体社会资本和个体社会资本。通过对Elsevier，Springer link和CNKI等平台上的文献进行梳理发现：在旅游领域，社会资本理论研究主要集中于集体和个体社会资本对旅游发展影响以及旅游对目的地社会资本影响等方面，研究呈现出内容上集中于社会资本对旅游的影响，方法上以案例分析为主的特点，当前仍存在不足，并提出今后研究的趋势，为以旅游创新助力乡村振兴，关注特色小镇发展模式，促进文化旅游可持续等，更好地运用社会资本理论来解释和解决旅游活动中的现象和问题，促进旅游业可持续发展。     

玩具机械物理能力验证技术分析及建议

文章介绍了广州海关技术中心玩具婴童用品实验室历年来组织的玩具机械物理领域的能力验证计划项目的基本情况,详细分析了各项目的技术要点和常见不满意问题,总结了现阶段该领域能力验证计划的开展情况。     

TOOLS FOR RE‐RANDOMIZATION

With the rising popularity of field experiments in economics, re‐randomization schemes have emerged as tools to induce balance in observable variables across treatment groups. However, re‐randomization is not fully understood and the methodologies to estimate its effects on the distribution of parameters are still under‐developed. This paper helps to close that gap by suggesting an asymptotically normal re‐randomization scheme and bootstrapping procedure to carry inference under a wide range of estimators and re‐randomization schemes.