| 1. |
- Segeborn, Johan, 1972, et al.
(författare)
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A Generalized method for weld Load balancing in multi station sheet metal assembly lines
- 2011
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Ingår i: Proceedings of the ASME 2011 International Mechanical Engineering Congress & Exposition IMECE2011 November 11-17, 2011, Denver, Colorado, USA.
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Konferensbidrag (refereegranskat)abstract
- Sheet metal assembly is investment intense. Therefore the equipment needs to be efficiently utilized. The balancing of welds has a significant influence on achievable production rate and equipment utilization. Robot line balancing is a complex problem, where each weld is to be assigned to a specific station and robot, such that line cycle time is minimized. Industrial robot line balancing has been manually conducted, based on experience and trial and error rather than mathematical methods. However, recently an automatic method for robot line balancing was proposed by the authors. To reduce robot coordination cycle time losses, this method requires identical reach ability of all line stations. This limits applicability considerably since in most industrial lines, reach ability differs over the stations to further line reach ability and flexibility.Therefore, in this work we propose a novel generalized simulation-based method for automatic robot line balancing that allows any robot positioning. It reduces the need for robot coordination significantly by spatially separating the robot weld work loads. This is furthermore achieved at a cost neglectable to line cycle time. The proposed method is furthermore successfully demonstrated on an automotive stud welding line. Moreover, algorithm CPU-times is a mere fraction of corresponding manual optimization times.
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| 2. |
- Carlsson, Fredrik, 1968, et al.
(författare)
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A Fair Share : Burden-Sharing Preferences in the United States and China
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Using a choice experiment, we investigated preferences for distributing the economic burden of decreasing CO2 emissions in the two largest CO2-emitting countries: the United States and China. We asked respondents about their preferences for four burden-sharing rules to reduce CO2 emissions according to their country’s 1) historical emissions, 2) income level, 3) equal right to emit per person, and 4) current emissions. We found that U.S. respondents preferred the rule based on current emissions, while the equal right to emit rule was clearly least preferred. The Chinese respondents, on the other hand, preferred the historical rule, while the current emissions rule was the least preferred. Respondents overall favored the rule that was least costly for their country. These marked differences may explain the difficulties countries face in agreeing how to share costs, presenting a tough hurdle to overcome in future negotiations. We also found that the strength of the preferences was much stronger in China, suggesting that how mitigation costs are shared across countries is more important there.
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| 3. |
- Carlsson, Fredrik, 1968, et al.
(författare)
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A fair share: Burden-sharing preferences in the United States and China
- 2013
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Ingår i: Resource and Energy Economics. - 0928-7655. ; 35:1, s. 1-17
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Tidskriftsartikel (refereegranskat)abstract
- Using a sequential discrete choice experiment, we investigate preferences for distributing the economic burden of reducing CO2 emissions in the two largest CO2-emitting countries: the United States and China. We asked respondents about their preferences for four burden-sharing rules to reduce CO2 emissions according to their country's relative (1) historical emissions, (2) income level, (3) emissions per capita, and (4) current emissions. We found that respondents overall favored the rule that was least costly for their country. In addition, the willingness to pay was much higher in China, suggesting that how mitigation costs are shared across countries is more important for Chinese than for Americans. To some extent the willingness to pay varies with socioeconomic characteristics and attitudes. For example, university-educated respondents in the United States are willing to pay more for the rule that is the least costly for their own country, compared with those with a lower education level. At the same time, the ranking of the two most preferred rules are generally robust across all socioeconomic groups within each country.
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| 4. |
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| 5. |
- Carlsson, Fredrik, 1968, et al.
(författare)
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Discrimination in scientific review - A natural field experiment on blind versus non-blind review
- 2012
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Ingår i: Scandinavian Journal of Economics. - : Wiley. - 1467-9442 .- 0347-0520. ; 114:2, s. 500-519
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Tidskriftsartikel (refereegranskat)abstract
- Using papers submitted to an international conference on economics held in Sweden in 2008, we analyze how gender, as well as other characteristics of the authors and reviewers, affects the grading of these papers by the reviewers. Correcting for other variables, including the country and research field, as well as the academic level of the author, we focus on the difference in grades between blind and non-blind review treatments. We find that non-blind reviewing has little effect, and there is no significant evidence of gender discrimination. Furthermore, we do not find any significant difference between the average grading by female and male reviewers.
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| 6. |
- Carlsson, Fredrik, 1968, et al.
(författare)
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Is Fairness Blind? - The effect of framing on preferences for effort-sharing rules
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- By using a choice experiment, this paper focuses on citizens’ preferences for effort-sharing rules of how carbon abatement should be shared among countries. We find that Swedes do not rank the rule favoring their own country highest. Instead, they prefer the rule where all countries are allowed to emit an equal amount per person, a rule that favors Africa at the expense of high emitters such as the U.S. The least preferred rule is reduction proportional to historical emissions. Using two different treatments, one where the respondents were informed about the country names and one where the country names were replaced with anonymous labels A-D, we also test whether people’s preferences for effort-sharing rules depend on the framing of the problem. We find that while the ranking of the principles is the same in both treatments, the strength of the preferences is significantly increased when the actual names of the countries are used.
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| 7. |
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| 8. |
- Carlsson, Fredrik, 1968, et al.
(författare)
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Paying for Mitigation: A Multiple Country Study
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Unique survey data from a contingent valuation study conducted in three different countries (China, Sweden, and the United States) were used to investigate the ordinary citizen’s willingness to pay (WTP) for reducing CO2 emissions. We find that a large majority of the respondents in all three countries believe that the mean global temperature has increased over the last 100 years and that humans are responsible for the increase. A smaller share of Americans, however, believes these statements, when compared to the Chinese and Swedes. A larger share of Americans is also pessimistic and believes that nothing can be done to stop climate change. We also find that Sweden has the highest WTP for reductions of CO2, while China has the lowest. Thus, even though the Swedes and Chinese are similar to each other in their attitudes toward climate change, they differ considerably in their WTP. When WTP is measured as a share of household income, the willingness to pay is the same for Americans and Chinese, while again higher for the Swedes.
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| 9. |
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| 10. |
- Carlsson, Fredrik, 1968, et al.
(författare)
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The Truth, the Whole Truth, and Nothing but the Truth - A Multiple Country Test of an Oath Script
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Hypothetical bias is one of the main issues bedeviling the field of nonmarket valuation. The general criticism is that survey responses reflect how people would like to behave, rather than how they actually behave. In our study of climate change and emissions reductions, we took advantage of the increasing bulk of evidence from psychology and economics that addresses the effects of making promises, in order to investigate the effect of an oath script in a contingent valuation survey. The survey was conducted in Sweden and China, and its results indicate that an oath script has significant effects on respondent behavior in answering willingness-to-pay (WTP) questions, some of which vary by country. In both countries, the share of zero WTP responses and extremely high WTP responses decreases when an oath script is used, which also results in lower variance. In China, the oath script also reduces the average WTP, cutting it by half in certain instances. We also found that the oath script has different impacts on various respondent groups. For example, without the oath script, Communist party members in China are more likely than others to have a positive WTP for emissions reductions, but with the oath script, there is no longer any difference between the groups.
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