基于JIT思想对汽车玻璃生产线WIP的控制策略

本文分析了汽车玻璃加工生产线的生产流程,生产车间不同种类的在制品(WIP)数量很庞大,为此研究生产线的瓶颈工序,得到瓶颈工序生产线的切换时间对WIP库存的影响,研究生产线的切换时间、工序之间的生产节拍比和WIP库存数三者之间的关系,结合JIT和WIP库存控制策略来保证生产线的流畅生产,归纳出关键的工序节拍比下所需的WIP库存数的动态变化情况,从而动态地控制WIP库存的变化并最大程度地降低车间的WIP库存。     

Land use regulation and urban land value: Evidence from China

Land use regulation has always been regarded as one of the most crucial means of macro-control of urban growth, which can affect a city’s land values directly and further determine related urban economic well-being. Since the New Type Urbanization Strategy proposed by the government in 2014, China’s mode of urban growth has been transformed from addressing “quantity” to “quality" in the urbanization process. In this case, the regulation of land use by the Chinese government plays a more important role in urban growth. With their planned land regulatory scheme, the various instruments employed by Chinese governments have quite different mechanisms influencing land prices. However, there are no rigorous studies focusing on the land use regulation system and its impact on land values to date, particular in China. This study seeks to explore how land use regulation affects urban land values through the systematic lens. We summarize the main land use regulatory instruments based on the analysis of China’s planned land use system and urban land banking system, including the construction land quota, constraints on the allowed floor area ratio (FAR) of each land transaction parcel, and land supply restrictions. A new dataset based on land transaction data from 2007 to 2016 that covers 286 prefectural cities from the country’s coastal, central, and western regions is used in the empirical analysis. The results show that the effects of the floor area ratio (FAR) on land values are significant and positive, with the residential and commercial land supply ratio being a key factor. Moreover, the results imply that the effects of constraints on FAR and commercial land supply vary between regions. These findings indicate that the Chinese land market is considerably distorted by excessive administrative interventions by local governments, in the stage of urban transition guided, the capable regulatory instruments could play an important role in adjusting urban land prices and hence impact on urban growth.     

Policy responses to an overheated housing market: Credit tightening versus transaction taxes

Among Asian economies, Hong Kong has experienced the highest real growth in house prices since the 2010s. Two macroprudential measures, namely credit tightening (loan-to-value ratio cap) and transaction taxes (stamp duty), were introduced to cool down the overheated housing market. This study examines and compares their effectiveness based on a set of constant-quality house price indices. Through an error correction model, we find that credit tightening was able to curb house price growth in the high-price segment, while transaction taxes could not. An explanation is that the exemptions from transaction taxes for those with genuine housing needs could be abused by other market participants. It is easier for buyers to exploit the exemptions to get around the stamp duty than to manipulate the property valuation for mortgage lending. The implication is that the effectiveness of macroprudential measures hinges on whether compliance or exemption can be easily monitored and enforced.     

Comparative randomized inverse sampling

According to previous literature, we define randomized inverse sampling for comparing two treatments with respect to a binary response as the sampling that stops when a total fixed number of successes, irrespective of the treatments, are observed. We have obtained elsewhere the asymptotic distributions for the counting variables involved and have shown them to be equivalent to the corresponding asymptotic distributions for multinomial sampling. In this paper, we start deriving the same basic results using different techniques, and we then show how they give rise to genuinely novel procedures when translated into finite sample approximations. As the main example, a novel confidence interval for the logarithm of the odds ratio of two success probabilities can be constructed in the case of comparative randomized inverse sampling. Some advantages over the standard multinomial sampling in terms of coverage probabilities are visible when no adjustment for cells with zero counts is applied; otherwise, the two sampling schemes appear to be fairly equivalent. This is a reassurance that under certain circumstances, inverse sampling can be safely chosen over more traditional sampling schemes.     

Value of hedge and expected returns

We demonstrate how it is possible to generate value for an investor with a hedge attached to the buy-and-hold strategy of an S&P 500 index fund. We study the S&P 500 index portfolio (not including dividends) and the value-weighted S&P 500 index portfolio (including dividends) of the Center for Research in Securities Prices for 1967:01–2011:12, using the capacity utilization and the unemployment rates in real time to determine if a hedge position should be initiated or closed. A hedge is initiated if the capacity utilization, the unemployment rate or a combination of the two signals a contraction in the real economy. The hedge position is closed if it signals otherwise an expansion. We use utility gains (Campbell and Thompson 2008), the manipulation-proof performance measure (MPPM) statistics (Ingersoll et al. 2007) and the P-Sharpe ratio (Bailey and López de Prado 2012) to evaluate the performance of a particular hedge strategy. The empirical results show that there are infinitely many hedges that can generate positive utility gains, higher MPPM statistics and higher P-Sharpe ratios.     

Good practices on cost – effective road infrastructure safety investments

The paper presents the findings of a research project aiming to quantify and subsequently classify several infrastructure-related road safety measures, based on the international experience attained through extensive and selected literature review and additionally on a full consultation process including questionnaire surveys addressed to experts and relevant workshops. Initially, a review of selected research reports was carried out and an exhaustive list of road safety infrastructure investments covering all types of infrastructure was compiled. Individual investments were classified according to the infrastructure investment area and the type of investment and were thereafter analysed on the basis of key safety components. These investments were subsequently ranked in relation to their safety effects and implementation costs and on the basis of this ranking, a set of five most promising investments was selected for an in-depth analysis. The results suggest that the overall cost effectiveness of a road safety infrastructure investment is not always in direct correlation with the safety effect and is recommended that cost–benefit ratios and safety effects are always examined in conjunction with each other in order to identify the optimum solution for a specific road safety problem in specific conditions and with specific objectives.     

Corporate giving in Taiwan: agency cost theory vs. value enhancement theory

This article examines the determinants of corporate giving (CG) in Taiwan according to agency cost (AC) and value enhancement (VE) theories. Panel regression test results reveal several new and interesting pieces of evidence. First, VE determinants outweigh AC determinants in explaining CG there. Second, the positive link between the current CG ratio (CGR) and the lagged CGR (CGR(-1)) suggests the consistent nature of CG. Third, after the global financial crisis in 2008, the influence of debt leverage on CGR vanished, but the impact of managerial insiders’ shareholdings on CGR became significant. Last, the influences of VE determinants and CGR(-1) on CGR remain during both pre-crisis and post-crisis periods. Moreover, after the crisis, CG was still motivated to create current value for shareholders, and was apparently used as a business strategy to signal companies’ financial or managerial stability.     

A net stable funding ratio for Islamic banks and its impact on financial stability: An international investigation

The Islamic Financial Services Board (IFSB) is the standard setting body for the Islamic banking industry. The IFSB, while endorsing the Basel III accord, modified the criteria to calculate the Net Stable Funding Ratio (NSFR) to cater for the unique aspects of the Islamic banking industry. In this paper, we calculated the modified NSFR of 136 Islamic banks from 30 jurisdictions between 2000 and 2013 and explored the potential impact the requirements of this ratio has on the financial stability of Islamic banks after controlling for bank, country, and market-specific variables. The empirical findings suggest that the modified NSFR has a positive impact on the financial stability of Islamic banks during the sample period. However, the marginal impact of the NSFR on stability diminishes as the size of the bank increases. The results remained robust after applying an alternative measure of stability and using an alternative estimation model based on an instrumental variable approach. These results validate the use of the IFSB’s modified NSFR for Islamic banks as a regulatory measure.     

用于通信系统的干扰对消电路设计与实现

针对通信设备应用的复杂化和对在复杂电磁环境下工作的设备电磁兼容性提出的更高要求，通过分析对消技术的基本原理，提出了一种模拟电路和数字电路相结合的干扰对消技术，并研制出了基于该技术的干扰对消原理样机。对该样机的单机测试和系统联试结果表明，该对消技术具备点频干扰和噪声干扰的抑制能力，对消收敛时间小于100 ms，对消比大于43 dB，适合在窄带通信中应用并可推广到其他领域。该成果正逐步在实际工程中得到运用。     

Stochastic Dominance Analysis of iShares

Abstract

Country indices as represented by iShares exhibit non-normal return distributions with both skewness and kurtosis. Earlier studies provide procedures for determining the statistical significance of stochastic dominance measures and the Sharpe Ratio. This present study uses these refinements to compare the performance of 18 country market indices. The iShares are indistinguishable when using the Sharpe Ratio as no significant differences are found. In contrast, stochastic dominance procedures identify dominant iShares. Although the results vary over time, stochastic dominance appears to be both more robust and discriminating than the CAPM in the ranking of the iShares.