Freedom Fries

Do firms choose inputs that minimize their cost of production, ignoring the attitudes of their owners and employees? We examine this question using an episode of worsening relations between the US and France: from February 2002 to March 2003, France's favorability rating in US public opinion polls fell from 83 percent to 35 percent. Very negative attitudes towards France became common even among college educated Americans with high levels of income, so they were likely prevalent among managers. Using data from 1999-2005, we find that the worsening relations reduced US imports from France by about 15 percent and US exports to France by about 8 percent, compared to other Eurozone or OECD countries. This decline was due in large part to a fall in France's share of the quantity of inputs traded between the Eurozone and the US; this decline is significant even after we control for changes in the product composition of trade flows. We also find that the decline in trade w as accompanied by a similar drop in both business trips and tourist visitations of US residents to France compared to Western Europe. Taken together, our findings suggest that competition cannot eliminate the effect of attitudes on firms' choice of inputs.Trade, Discrimination

Capacity Analysis and Throughput Maximization of NOMA with Nonlinear Power Amplifier Distortion

In future B5G/6G broadband communication systems, non-linear signal distortion caused by the impairment of transmit power amplifier (PA) can severely degrade the communication performance, especially when uplink users share the wireless medium using non-orthogonal multiple access (NOMA) schemes. This is because the successive interference cancellation (SIC) decoding technique, used in NOMA, is incapable of eliminating the interference caused by PA distortion. Consequently, each user's decoding process suffers from the cumulative distortion noise of all uplink users. In this paper, we establish a new and tractable PA distortion signal model based on real-world measurements, where the distortion noise power is a polynomial function of PA transmit power diverging from the oversimplified linear function commonly employed in existing studies. Applying the proposed signal model, we characterize the capacity rate region of multi-user uplink NOMA by optimizing the user transmit power. Our findings reveal a significant contraction in the capacity region of NOMA, attributable to polynomial distortion noise power. For practical engineering applications, we formulate a general weighted sum rate maximization (WSRMax) problem under individual user rate constraints. We further propose an efficient power control algorithm to attain the optimal performance. Numerical results show that the optimal power control policy under the proposed non-linear PA model achieves on average 13\% higher throughput compared to the policies assuming an ideal linear PA model. Overall, our findings demonstrate the importance of accurate PA distortion modeling to the performance of NOMA and provide efficient optimal power control method accordingly.Comment: The paper has been submitted for potential journal publication

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Freedom fries

Do firms choose inputs that minimize their cost of production, ignoring the attitudes of their owners and employees? We examine this question using an episode of worsening relations between the US and France: from February 2002 to March 2003, France's favourability rating in US public opinion polls fell from 83 percent to 35 percent. Very negative attitudes towards France became common even among college educated Americans with high levels of income, so they were likely prevalent among managers. Using data from 1999-2005, we find that the worsening relations reduced US imports from France by about 15 percent and US exports to France by about 8 percent, compared to other Eurozone or OECD countries. This decline was due in large part to a fall in France's share of the quantity of inputs traded between the Eurozone and the US; this decline is significant even after we control for changes in the product composition of trade flows. We also find that the decline in trade was accompanied by a similar drop in both business trips and tourist visitations of US residents to France compared to Western Europe. Taken together, our findings suggest that competition cannot eliminate the effect of attitudes on firms' choice of inputs

Freedom fries

Do firms always choose the cheapest suitable inputs, or can group attitudes affect their choices? To investigate this question, we examine the deterioration of relations between the United States and France from 2002-2003, when France's favorability rating in the US fell by 48 percentage points. We estimate that the worsening attitudes reduced bilateral trade by about 9 percent and that trade in inputs probably declined similarly, by about 8 percent. We use these estimates to calculate the average decrease in firms' willingness to pay for French (or US) commodities when attitudes worsened

Freedom Fries

Do firms choose inputs that minimize their cost of production, ignoring the attitudes of their owners and employees? We examine this question using an episode of worsening relations between the US and France: from February 2002 to March 2003, France's favourability rating in US public opinion polls fell from 83 percent to 35 percent. Very negative attitudes towards France became common even among college educated Americans with high levels of income, so they were likely prevalent among managers. Using data from 1999-2005, we find that the worsening relations reduced US imports from France by about 15 percent and US exports to France by about 8 percent, compared to other Eurozone or OECD countries. This decline was due in large part to a fall in France's share of the quantity of inputs traded between the Eurozone and the US; this decline is significant even after we control for changes in the product composition of trade flows. We also find that the decline in trade was accompanied by a similar drop in both business trips and tourist visitations of US residents to France compared to Western Europe. Taken together, our findings suggest that competition cannot eliminate the effect of attitudes on firms' choice of inputs.Discrimination; Trade

Very High Cycle Fatigue Life Prediction of SLM AlSi10Mg Based on CDM and SVR Models

A novel fatigue evolution model considering the effect of defect size and additive manufacturing building direction based on the theories of continuum damage mechanics and its numerical implementation in ABAQUS is proposed in this paper. First, the constitutive model, fatigue damage evolution model and their parameter calibration methods are presented. Second, using the ABAQUS platform, the proposed model is implemented with user-defined subroutines. After that, based on the proposed model and its numerical implementation, the fatigue life of additively manufactured AlSi10Mg is predicted and its applicability is verified through experimental results. Finally, a support vector regression model is established to predict the fatigue life, and its results are compared to those of the numerical finite element method. The results show that the support vector regression model makes better predictions than the finite element method