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1.
姜胜贤  文天凤 《科技和产业》2023,23(13):164-168
近年来,大量企业基于数字化转型实现了弯道超车。选取2007—2021年A股上市公司数据,利用企业年报中数字关键词的词频来描述数字化转型程度,研究企业数字化转型程度对企业融资成本的影响。研究发现:企业数字化转型与融资成本显著负相关;检验延长时间窗口发现,在企业实施数字化转型后的一段时间内,数字化转型仍然降低了融资成本;根据异质性分析,数字化转型对非国有企业降低融资成本产生的效果更好,且东部地区企业深化数字化转型降低成本的作用更显著。  相似文献   
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山秋月  吴永强 《科技和产业》2023,23(14):223-227
针对全货运航空公司,研究其货运航线网络的构建问题。基于单分配严格枢纽航线网络,对传统模型进行改进。以各航线上货物的委托运输成本和自有机队的运输成本,取代传统的单位运输成本和折扣因子,考虑枢纽点的中转成本和载运率对路径选择的影响。结合航空货运夜航的特征考虑各机队夜间可用时间的限制,以总成本最小为目标,构建数学模型,采用LINGO优化软件求解,验证模型的有效性,为全货运航空公司构建货运航线网络提供参考。  相似文献   
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在国际货物销售合同纠纷中,争议解决费用往往是不可忽视的内容。在此基础之上,探讨CISG视角下的争议解决费用分摊问题兼具理论和实际意义。理论和实践中就CISG能否成为分摊争议解决费用的依据存在不同做法。差异背后的深层次原因在于有关方对CISG的立法精神和解释规则存在理解上的不同。本文支持依CISG分摊争议解决费用的观点,因为这不仅更契合于公约的精神,也更能实现公约适用的统一。域外的相关公约实践对我国同样具有借鉴意义。对于我国的有关实践,本文有4点建议:通过合同条款对争议解决费用的分摊加以明确;明确争议解决费用分摊的请求权基础;裁判主体应克服国内法思维,恪守公约精神进行条款的解释与适用;进一步明确争议解决费用分摊的国内法规则,从而实现国际法与国内法适用的统一。  相似文献   
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Instructional Manipulation Checks (IMCs) assess respondent behavior by, for example, asking participants not to answer a trick question. We find IMCs can be used to detect problematic response behavior in longitudinal surveys. This is important because a Latent Class Analysis based on IMC-failure in the two reported studies reveals that between 9% and 12% of respondents can be labelled Inattentive Stayers at the first survey-wave and between 13% and 17% at the third wave. The tendency of Inattentive Stayers to remain in the panel is particularly relevant for online panel services such as MTurk, with workers participating in many surveys over longer time-periods. We find IMC-failure to be mitigated by a warning to respondents that their attention will be checked early in the survey, but not by repeated exposure to IMCs, or a timer leaving questions on the screen longer. Respondent personality also plays a role in IMC-failure, which implies persistency of undesirable respondent behavior.  相似文献   
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Aims: To estimate the cost to hospitals of materials (i.e. medications, equipment, and supplies) required to administer common interventions for post-surgical analgesia after total knee arthroplasty (TKA), including single-injection peripheral nerve block (sPNB), continuous peripheral nerve block (cPNB), periarticular infiltration of multi-drug cocktails, continuous epidural analgesia, intravenous patient-controlled analgesia (IV PCA), and local infiltration of bupivacaine liposome injectable suspension (BLIS).

Materials and methods: This analysis was conducted using a mixed methods approach combining published literature, publicly available data sources, and administrative data, to first identify the materials required to administer these interventions, and then estimate the cost to the hospital of those materials. Medication costs were estimated primarily using the Wholesale Acquisition Costs (WAC), the cost of reusable equipment was obtained from published sources, and costs for disposable supplies were obtained from the US Government Services Administration (GSA) database. Where uncertainty existed about the technique used when administering these interventions, costs were calculated for multiple scenarios reflecting different assumptions.

Results: The total cost of materials (i.e. medications, equipment, and supplies) required to provide post-surgical analgesia was $41.88 for sPNB with bupivacaine; $756.57 for cFNB with ropivacaine; $16.38 for periarticular infiltration with bupivacaine, morphine, methylprednisolone, and cefuroxime; $453.84 for continuous epidural analgesia with fentanyl and ropivacaine; $178.94 for IV PCA with morphine; and $319.00 for BLIS.

Limitations: This analysis did not consider the cost of healthcare providers required to administer these interventions. In addition, this analysis focused on the cost of materials and, therefore, did not consider aspects of relative efficacy or safety, or how the choice of intervention for post-surgical analgesia might impact outcomes such as length of stay, re-admissions, discharge status, adverse events, or total hospitalization costs.

Conclusions: This study provided an estimate of the costs to hospitals for materials required to administer commonly used interventions for post-surgical analgesia after TKA.  相似文献   
8.
We examine private issuance of public equity (PIPE) in China, and our results suggest that PIPE investors benefit from the price manipulation before and after issuance. These investors tend to cash out after lockup expiration and make large profits. We also find evidence that the trading of PIPE investors after lockup expiration is informed. Tests about the abnormal returns in the 3 years after lockup expiration suggest that at least part of the benefits PIPE investors receive come from wealth transfer from outside investors. Overall, PIPE issuers in China seem to use an opaque mechanism to compensate PIPE investors.  相似文献   
9.
Using the workweek of capital as a measure of capital utilization, we empirically test whether news shocks actually increase capital utilization. To this end, by estimating a panel VAR on two-digit manufacturing data identifying news shocks as innovations to stock returns orthogonal to the variations in current-period TFP growth, we find the positive response of capital utilization to news shocks. Moreover, to explain the positive response of capital utilization to news shocks in terms of plant-level investment behavior, we propose a heterogeneous plant model that combines the fixed cost of capital adjustment and an endogenous capital utilization choice. With the presence of fixed costs, except for the plants that have recently adjusted capital stock, news shock shortens the effective time horizon of currently installed capital stock and increases capital utilization. When the model economy is calibrated to match the salient features of the plant-level investment rate distribution, the economy generates a news-driven positive response of capital utilization.  相似文献   
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