Concurrency bugs are extremely hard to detect due to huge interleaving space. They are happening in the real world more often because of the prevalence of multi-threaded programs taking advantage of multi-core hardware, and microservice based distributed systems moving more and more applications to the cloud. As the most common non-deadlock concurrency bugs, atomicity violations are studied in many recent works, however, those methods are applicable only to single-variable atomicity violation, and don't consider the specific challenge in distributed systems that have both pessimistic and optimistic concurrency control. This dissertation presents a tool using model checking to predict atomicity violation concurrency bugs involving two shared variables or shared resources. We developed a unique method inferring correlation between shared variables in multi-threaded programs and shared resources in microservice based distributed systems, that is based on dynamic analysis and is able to detect the correlation that would be missed by static analysis. For multi-threaded programs, we use a binary instrumentation tool to capture runtime information about shared variables and synchronization events, and for microservice based distributed systems, we use a web proxy to capture HTTP based traffic about API calls and the shared resources they access including distributed locks. Based on the detected correlation and runtime trace, the tool is powerful and can explore a vast interleaving space of a multi-threaded program or a microservice based distributed system given a small set of captured test runs. It is applicable to large real-world systems and can predict atomicity violations missed by other related works for multi-threaded programs and a couple of previous unknown atomicity violation in real world open source microservice based systems. A limitation is that redundant model checking may be performed if two recorded interleaved traces yield the same partial order model.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18076号 / 理博第3954号 / 新制||理||1570(附属図書館) / 30934 / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)准教授 野村 正, 教授 中家 剛, 教授 鶴 剛 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

The Qweak experiment has taken data to make a 2.5 percent measurement of parity violating elastic ep asymmetry in the four momentum transfer region of 0.0250 (GeV/c)2. This asymmetry is proportional to the weak charge of the proton, which is related to the weak mixing angle, sin2(thetaW). The final Qweak measurement will provide the most precise measurement of the weak mixing angle below the Z° pole to test the Standard Model prediction. A description of the experimental apparatus is provided in this dissertation. The experiment was carried out using a longitudinally polarized electron beam of up to 180 microampere on a 34.5 cm long unpolarized liquid hydrogen target. The Qweak target is not only the world’s highest cryogenic target ever built for a parity experiment but also is the least noisy target. This dissertation provides a detailed description of this target and presents a thorough analysis of the target performance. Statistical analysis of Run 1 data, collected between Feb - May 2011, is done to extract a blinded parity violating asymmetry of size--299.7 +/- 13.4 (stat.) +/- 17.2 (syst.) +/- 68 (blinding) parts-per-billion. This resulted in a preliminary proton’s weak charge of value 0.0865 +/- 0.0085, a 9% measurement. Based on this blinded asymmetry, the weak mixing angle was determined to be sin2(thetaW) = 0.23429 +/- 0.00211.

This thesis studies CP violation in the decay of the Ξ− hyperon, also known as the cascade baryon, which decays in the sequence Ξ− → Λπ− → pπ−π−. A difference between the angular distribution of this decay sequence and the angular distribution of the charge conjugate decay sequence ͞Ξ+ →͞Λπ+ → ͞pπ+π+, after taking into account the inversion of the momenta due to the parity operation, is indicative of CP violation. The decay sequence is described by three asymmetry parameters: αΞ, αΛ and φΞ, while the charge conjugate decay's sequence is described by: ͞αΞ, ͞αΛ and ͞φΞ. A measure of CP violation is given by the CP violating observables: AΞ, AΛ and ΦΞ. The aim of this thesis is to study how the normalised statistical uncertainties in the asymmetry parameters and in the CP violating observables depend on the magnitude of the polarisation vector (polarisation) of the cascade and the anticascade. This was done by simulating 1.0×107 Ξ− → Λπ− → pπ−π− and  ͞Ξ+ →͞Λπ+ → ͞pπ+π+ decays for different values of polarisation of the cascades using Monte Carlo, and then utilising maximum likelihood estimation and error propagation to estimate the uncertainties in the parameters and in the observables. It was shown using the methods of this thesis that the normalised statistical uncertainties in the asymmetry parameters and the CP violating observables decreased whenever the polarisation was increased, although with diminishing returns. In the region of 10% − 50% polarisation, the decrease in the uncertainties was substantial. An increase from 10% to 50% polarisation lowered all of the uncertainties by 76% − 80%. In the region of 50% − 100% polarisation, the decrease in the uncertainties was slightly less. An increase from 50% to 100% polarisation lowered the uncertainties in αΞ,  ͞αΞ and AΞ by roughly 33%, in αΛ,  ͞αΛ and AΛ by roughly 40%, and in φΞ,  ͞φΞ and ΦΞ it went down by 53%. It was also shown that, if one were to produce 60% polarised cascades and use the method of this thesis, it would require a sample of 1.1×1011 − 1.3×1011 Ξ− → Λπ− → pπ−π− and  ͞Ξ+ →͞Λπ+ → ͞pπ+π+ decays to reach the precision in the observables of the order given by the Standard Model. However, if one wished to match the uncertainty given by the most recent and best measurement of the observables, using 60% polarised cascades, one would only need a sample of 5.7×104 − 8.6×104 for each decay sequence.

No description available.

Across domains, organizations and society are facing a trust deficit (Twenge, Campbell, & Carter, 2014). This is problematic, as trust is important to a variety of critical organizational outcomes, such as perceived task performance, team satisfaction, relationship commitment, and stress mitigation (Costa, Roe, & Taillieu, 2001), and has been cited as a motivator for cooperation and knowledge transfer due to its capacity to reduce fear and risk of exploitation (Chen et al., 1998; Fleig-Palmer & Schoorman, 2011; Irwin & Berigan, 2013; Yamagishi & Sato, 1986), and a key component of collaboration. As organizations increasingly rely upon collaboration for achieving important outcomes, it is of critical importance that organizations understand how to not only develop interpersonal trust in collaborative partnerships to facilitate these positive outcomes, but also the way in which interpersonal trust is broken and can be repaired when problems inevitably arise. Though research has begun to investigate trust violation and trust repair, relatively little is known about trust development, violation, and repair as a process that unfolds over time. This is problematic, as cross-sectional studies fail to capture change, both in terms of how trust itself changes as well as how the effect of a violation or the utility of a repair strategy may be weaker or stronger in the long-term than the short-term. Thus, findings from a single point in time may result in different conclusions and recommendations than those that would result from long-term investigation. Therefore, this study examines how interpersonal trust patterns unfold within individuals, and how these patterns differ between individuals depending on the type of violation and the repair strategy employed. An experimental study using discontinuous growth modeling to examine intraindividual and interindividual differences in trust processes found that generally, trust was negatively impacted more after an intentional ("will do") violation as compared to a competence ("can do") violation, such that it had a greater impact on character assessments than a competence violation and also damaged perceptions of ability as much as a competence violation. These negative impacts carried over into trust restoration, which was significantly slower after an intentional violation than a competence violation. Furthermore, study findings suggest that after an intentional violation, trust restored more quickly when surveillance was implemented than when compensation was offered. Though the opposite did not hold true for a competence violation, the findings did approach significance. Drawing from these findings, implications and future research recommendations are discussed.

No description available.

京都大学 / 新制・課程博士 / 博士(理学) / 甲第24962号 / 理博第4987号 / 新制||理||1712(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 中家 剛, 教授 永江 知文, 教授 田島 治 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

Millions of people's lives have been upended by the COVID-19 pandemic, which has also worsened existing inequalities and led to widespread abuses of human rights. This report examines the rise in teen marriage in Niger as a result of the global epidemic. The closure of schools, economic hardship, and social isolation have made females vulnerable to early marriage as families strive to reduce financial pressures or safeguard daughters from getting the virus. This report examines the causes of child marriage in Niger, the impacts of the pandemic on girls' rights, and the measures taken by government and civil society organisations to combat the issue. The document argues that child marriage violates girls' rights and perpetuates a cycle of poverty and poor health outcomes. The report concludes that urgent action is required to protect the rights of girls and end the harmful practise of child marriage, especially in light of the Covid-19 pandemic. This case study highlights the importance of addressing human rights violations during crises such as the COVID-19 pandemic, as well as the necessity of sustained efforts to promote gender equality and protect the rights of women and girls.

Against the background of an increasing number of cyclists sharing the infrastructure with an also rising number of e-scooter riders in Germany, the question of considerate coexistence among both modes of transportation, especially on shared infrastructure (on- or off-road) arises. In various contexts (e.g. work, education), studies have shown that social identity has an impact on how members of an ingroup ('us') and outgroup (''them') are perceived. These studies are based on social identity theory, which postulates members of the ingroup are more likely to be favored and members of the outgroup are more likely discriminated and stereotyped. This ingroup favorism or outgroup discrimination can refer to attitudes, cognition, and behavior. Initial research in the traffic context by, on which the present study builds, suggests that social identity also plays a role in traffic. Apart from that, research on social identity in traffic is scarce. The aim of the study is to determine whether the role as cyclist or e-scooter rider in traffic can serve as social identity, and subsequently whether ingroup-outgroup phenomena, such as ingroup favorism and effects of outgroup discrimination can be observed. [from Introduction]