A simple technique for combining simplified models and its application to direct stop production

The results of many LHC searches for supersymmetric particles are interpreted using simplified models, in which one fixes the masses and couplings of most sparticles then scans over a few remaining masses of interest. We present a new technique for combining multiple simplified models (that requires no additional simulation) thereby highlighting the utility and limitations of simplified models in general, and demonstrating a simple way of improving LHC search strategies. The technique is used to derive limits on the stop mass that are model independent, modulo some reasonably generic assumptions which are quantified precisely. We find that current ATLAS and CMS results exclude stop masses up to 340 GeV for neutralino masses up to 120 GeV, provided that the total branching ratio into channels other than top-neutralino and bottom-chargino is small, and that there is no mass difference smaller than 10 GeV in the mass spectrum. In deriving these limits we place upper bounds on the branching ratios for complete stop pair decay processes for many values of the stop, neutralino and chargino masses. These are available with this paper.Comment: 25 pages, data included in source. V3: new content added, version accepted for publicatio

Hydraulic mechanism to limit torsional loads between the IUS and space transportation system orbiter

The Inertial Upper Stage (IUS) is a two-stage booster used by NASA and the Defense Department to insert payloads into geosynchronous orbit from low-Earth orbit. The hydraulic mechanism discussed here was designed to perform a specific dynamic and static interface function within the Space Transportation System's Orbiter. Requirements, configuration, and application of the hydraulic mechanism with emphasis on performance and methods of achieving zero external hydraulic leakage are discussed. The hydraulic load-leveler mechanism meets the established design requirements for operation in a low-Earth orbit. Considerable testing was conducted to demonstrate system performance and verification that external leakage had been reduced to zero. Following each flight use of an ASE, all hydraulic mechanism components are carefully inspected for leakage. The ASE, including the hydraulic mechanism, has performed without any anomalies during all IUS flights

Affirmative Action: Problems and Prospects

We live in complicated times today, and one of the sparks that flies off from such complicated times involving difficult issues is that words have all kinds of meanings, and they tend to confuse. I was astonished to hear our president, Ronald Reagan, say that if Dr. King were alive he would agree with him in opposing affirmative action, because King was color-blind and so is Ronald Reagan. This was a stopper, really, a real stopper. Affirmative action has had an interesting history. I, with no attempted modesty, claim to have proposed the idea to Lyndon Johnson, in either late 1962 or early 1963, when he was Vice President

Affirmative Action: Problems and Prospects

Affirmative action has had an interesting history. I, with no attempted modesty, claim to have proposed the idea to Lyndon Johnson in either late 1962 or early 1963 when he was vice president. The only person I known who would disagree with me on that is the late Whitney Young, and he is not present to voice his disagreement now. When I reported to the Council on United Civil Rights Leadership, the group that was called the Big Six or the Big Four by the media, that I had had such a meeting with Vice President Lyndon Johnson and had proposed this idea, to which he gave the name affirmative action, Whitney said, Well, I discussed the same idea with Jack Kennedy. So perhaps we, in contemplating the same set of facts, had reached the same conclusion that something new was needed to deal with the terrible job situation that minorities found themselves in. We were making progress, it is true. Blacks were getting better jobs and black income was increasing but that was in absolute terms, not in relative terms. We were not closing the gap. As we (blacks) rose, the majority rose faster; the gap widened, and so we had to do something else. Well, that was one indication of the complex days we were entering then

A comparison of conventional heating techniques and microwave irradiation for the desorption of lithium borohydride and lithium borohydride composites

The desorption of lithium borohydride and lithium borohyride composites was examined using both conventional heating techniques and microwave irradiation. LiBH4 was milled with TiH2 in various molar ratios in an argon atmosphere using both roller and planetary mill techniques. Thermo-gravimetric analysis and differential scanning calorimetry determined the desorption characteristics of the as received and milled materials. Scanning electron microscopy was used to examine the particle size of the materials before heating. A temperature programmed desorption (TPD) rig and a custom built microwave rig were both connected to the same gas aborption system which was pressurised with hydrogen and could be operated with each system independently. A comparison in desorption characteristics was made between conventional TPD heating techniques and microwave irradiation for the as received and milled materials; mass flow controllers were able to measure the amount of hydrogen desorbed in both cases. X-ray diffraction was conducted on the samples before and after heating in the TPD rig. TiH2 was found to kinetically destabilise the desorption of LiBH4 in all techniques. Microwave induced desorption produced faster heating rates than were exhibited with conventional heating techniques using less energy, with similar amounts of hydrogen gas being desorbed in a much shorter time period

Natural gauge mediation with a bino NLSP at the LHC

Natural models of supersymmetry with a gravitino LSP provide distinctive signatures at the LHC. For a neutralino NLSP, sparticles can decay to two high energy photons plus missing energy. We use the ATLAS diphoton search with 4.8 fb^{-1} of data to place limits in both the stop-gluino and neutralino-chargino mass planes for this scenario. If the neutralino is heavier than 50 GeV, the lightest stop must be heavier than 580 GeV, the gluino heavier than 1100 GeV and charginos must be heavier than approximately 300-470 GeV. This provides the first nontrivial constraints in natural gauge mediation models with a neutralino NLSP decaying to photons, and implies a fine tuning of at least a few percent in such models.Comment: 10 pages, 3 figures; v2: updated figure 3, version published in PR

Labour Relations - A Takeover by the State? The New Zealand Experience

The debate on the question of the role of law in labour relations is not new. At the one extreme, there is the oft quoted statement of Professor Wedderburn that "Most workers want nothing more of the law than it should leave them alone" so that "legal sanction and lawyers make their greatest contribution to industrial life by being self-effacing rather than obtrusive.

Learning Without Teaching : The Practice and Benefits of the Nelson-Heckmann Method of Socratic Dialogue

The subject of this dissertation is the Nelson-Heckmann Socratic Dialogue, a pedagogical method developed by the German philosophers and educators, Leonard Nelson (1882 - 1927), and Gustav Heckmann (1898 - 1996). The purpose of the research carried out here is to understand how Nelson-Heckmann Socratic Dialogues are conducted, to establish what the benefits are of participating in such dialogues, and to find out if the people who participate in Socratic Dialogues experience any of the expected benefits. The dissertation proceeds in the following way. Chapter one provides an introduction to Socratic Dialogue, and outlines why empirical research about Socratic Dialogue is worthwhile. Chapter two explains the philosophical underpinnings of Socratic Dialogue and outlines the process of conducting a dialogue. It then goes on to review the literature concerning Socratic Dialogue, focusing specifically on the claims made about the benefits of participating in a Socratic Dialogue. Chapter three outlines the research methodology and details the research method. Chapters four and five present and discuss the research findings, and chapter six concludes the study and presents further reflections on Socratic Dialogue. Reviewing the literature it was found that there are seven benefits which participants are said to experience as a result of participating in Socratic Dialogues, which are that it enables participants to: i) review and revise (and reject) some of their opinions, widen their vision, and gain insight into some of their beliefs; ii) experience the advantages of constructively and cooperatively thinking together; iii) recognise the educational value of personal experience; iv) improve their critical thinking, reasoning and arguing skills; v) learn that a heterogeneous group of people are able to reach genuine and meaningful consensus about challenging subjects; vi) expand their model(s) of what learning is, and of how and under what conditions it can take place; vii) strengthen their own values, and make the world in which they live more ethical, decent and humane. Three Socratic Dialogues were facilitated as part of the research, and focus groups were conducted with participants immediately afterwards. Analysis of the focus group data showed that, for the most part, the benefits of Socratic Dialogue as suggested by the literature are experienced by the participants who take part in the dialogues

Analysis of on-orbit thermal characteristics of the 15-meter hoop/column antenna

In recent years, interest in large deployable space antennae has led to the development of the 15 meter hoop/column antenna. The thermal environment the antenna is expected to experience during orbit is examined and the temperature distributions leading to reflector surface distortion errors are determined. Two flight orientations corresponding to: (1) normal operation, and (2) use in a Shuttle-attached flight experiment are examined. A reduced element model was used to determine element temperatures at 16 orbit points for both flight orientations. The temperature ranged from a minimum of 188 K to a maximum of 326 K. Based on the element temperatures, orbit position leading to possible worst case surface distortions were determined, and the subsequent temperatures were used in a static finite element analysis to quantify surface control cord deflections. The predicted changes in the control cord lengths were in the submillimeter ranges

The Hero’s Journey in Higher Education : A Twelve Stage Narrative Approach to the Design of Active, Student-Centred University Modules

This paper outlines and makes the case for a new, twelve stage narrative approach to the design of university modules. The twelve stages in the narrative approach to module design mirror the twelve stages which comprise the hero’s journey in myth and legend, as discussed in the work of Campbell (1993) and Vogler (1985). The purpose of designing a university module to mirror the stages of the hero’s journey is twofold. Firstly, it is proposed that the use of a narratively-focused design will lead to a greater sense of satisfaction on the part of those taking the module, because the narrative approach considers, for example, the importance of beginnings and endings, as well as the emotional journey of the participants. Secondly, the narrative approach is constructed to create module designs which are active and student-centred, thus a very strong emphasis is placed on what the students will be doing in each of the stages. Throughout the paper each of the twelve stages is explained, and an example of what the teacher and students might do in each of the stages is given. This narrative approach to module design has been constructed primarily for teachers who would like to design their modules to be more active and student centred, but who are unsure how to go about this and would like a supportive framework within which the module can be designed