Littérature scientifique sur le sujet « Equitu duration »

We analyze the cross-sectional expected return of KOSPI stocks using equity duration. From 1991 to 2018, we calculate equity durations for the KOSPI listed stocks (including de-listed stocks) and find that the shorter the equity duration, the higher the risk premium. Using the 4-factor model with equity duration added to the benchmark 3-factor model, the explanatory power of the 4-factor model is superior to that of the existing benchmark model in accounting for risk premiums. This is an unusual finding that is not readily explainable by the traditional CAPM or the Fama-French 3-factor model. This can be interpreted that the equity duration is a separate and significant risk factor dissociated from the HML of the 3-factor model.

This thesis consists of three empirical essays studying the capital market implications of the accounting for R&D costs. The first empirical study (Chapter 2) re-visits the debate over the positive R&D-returns relation. The second empirical study (Chapter 3) examines the risk relevance of current R&D accounting. The third empirical study (Chapter 4) explores the joint impact of R&D intensity and competition on the relative relevance of the idiosyncratic part of earnings. Prior research argues that the positive relation between current R&D activity and future returns is evidence of mispricing, a compensation for risk inherent in R&D or a transformation of the value/growth anomaly. The first empirical study contributes to this debate by taking into account the link between R&D activity, equity duration and systematic risk. This link motivates us to employ Campbell and Vuolteenaho (2004)'s intertemporal asset pricing model (ICAPM) which accommodates stochastic discount rates and investors' intertemporal preferences. The results support a risk based explanation; R&D intensive firms are exposed to higher discount rate risk. Hedge portfolio strategies show that the mispricing explanations is not economically significant. The second empirical study contributes to prior research on the value relevance of financial reporting information on R&D, by proposing an alternative approach which relies on a return variance decomposition model. We find that R&D intensity has a significant influence on market participants' revisions of expectations regarding future discount rates (or, discount rate news) and future cash flows (or, cash flow news), thereby driving returns variance. We extend this investigation to assess the risk relevance of this information by means of its influence on the sensitivity of cash flow and discount rate news to the market news. Our findings suggest R&D intensity is associated with significant variation in the sensitivity of cash flow news to the market news which implies that financial reporting information on R&D is risk relevant. Interestingly, we do not establish a similar pattern with respect to the sensitivity of discount news to the market news which may dismiss the impact of sentiment in stock returns of R&D intensive firms. The third empirical study examines the effect of financial reporting information on R&D to the value relevance of common and idiosyncratic earnings. More specifically, we investigate the value relevance of common and idiosyncratic earnings through an extension of the Vuolteenaho (2002) model which decomposes return variance into its discount rate, idiosyncratic and common cash flow news. We demonstrate that the relative importance of idiosyncratic over common cash flow news in explaining return variance increases with firm-level R&D intensity. Extending this analysis, we find that this relation varies with the level of R&D investment concentration in the industry. Those results indicate that the market perceives that more pronounced R&D activity leads to outcomes that enable the firm to differentiate itself from its rivals. However, our results also suggest that the market perceives that this relation depends upon the underlying economics of the industry where the firm operates.

In this paper I use an equity duration framework to develop and empirically test the hypothesis that returns on growth stock portfolios react more strongly to Federal Funds target rate change announcements, as compared to value stock portfolios. When I decompose the Federal Funds rate change, I find that portfolio returns are only sensitive to rate shocks, as opposed to the predictable component of rate change. Since growth stocks are expected to have higher duration than value stocks, I further explore the well documented polarity between value and growth stocks, by examining the interest rate sensitivities of portfolios that diverge along four fundamental-to-prices ratios: dividend yield, book-to-market value, earnings-to-price and cashflows-to-price. In each case, I find that price reactions are more pronounced for portfolios with high growth characteristics. I also document that portfolio returns react asymmetrically to positive and negative target rate surprises, and that this reaction is conditional on the state of business cycles - periods of economic expansions and recessions. To improve the robustness of my results, several statistical applications have been applied. First, I include Newey-west estimators to examine significant levels of regression estimates. Second, I check if there is any contemporaneous correlation across target rate shocks by applying ARIMA tests, and to overcome the problem resulted from serial correlation of target rate shocks, I substitute white noise residuals from the regressions on the rate shocks for target rate shocks to be new exogenous variables.

Thesis (MComm)--Stellenbosch University, 2002.
ENGLISH ABSTRACT: This assignment sets out to address the concept of equity duration, where equity duration is viewed as a measure of the interest rate sensitivity of common stock's market value. The traditional use of standard dividend discount models, results in extremely long duration estimates for equities - in the order of 10 years for income stocks to 25 years and more for growth companies whose cash flows are not expected to materialize until some future period. Leibowitz (1986) identified an alternative approach for assessing equity duration empirically. These empirical estimates of actual stock price sensitivity to underlying changes in interest rates imply that equities behave as if they are much shorter duration instruments. Various attempts have been made to reconcile the difference between theoretical predictions of equity duration and empirical findings. The differences in duration of assets in place and growth opportunities are given as a possible reason for the above mentioned differences. It is argued that investment opportunities are similar to options a company has. These option-like characteristics of growth opportunities may alter the basic relationship between equity valuation and interest rate changes. The option framework suggests that the duration of growth companies may be shorter (not longer) than those of assets in place. The results from option theory can however not be applied directly to growth options, since some of the assumptions may not be valid in the case of growth options. The presence of these growth options makes it virtually impossible to calculate equity duration theoretically. This study empirically tests the relationship between growth opportunities and equity duration by focussing the attention on the interest rate sensitivity of South African growth companies. The following hypotheses regarding equity duration and growth companies are postulated: • There is a significant difference in interest rate sensitivity between growth companies and low-growth companies. • There is a significant difference between duration of growth companies measured using nominal interest rates and duration of growth companies using real interest rates. All non-mining companies on the Johannesburg Securities Exchange SA, for the period 1980 to 2000, were analysed. These companies were sorted into different portfolios that reflected their growth opportunities. Market capitalisation, book-to-market and price-earnings ratios were used as proxies to rank companies according to growth opportunities. The results from univariate regressions suggest positive duration for common equities. The negative relationship between equity returns and changes in nominal interest rates are independent of size, book-to-market or price-earnings ratios of the sampled companies. Including the market factor as an independent variable results in markedly different equity duration. The duration is correlated with size, as both coefficients and t-statistics increase when moving from small companies to larger companies. In addition, the small companies have negative not positive duration, as was the case for simple univariate regressions. There is also some evidence that high growth portfolios, as measured by low book-to-market and high price-earnings ratios, are less sensitive to interest rate changes than low growth portfolios. Employing all three Fama and French's factors, there is no longer a cross-sectional dependence on company size, with the mean duration being close to zero and statistically insignificant in virtually all cases. Also, when dividing changes in the nominal interest rate into changes in real rates and changes in inflation, it does not significantly affect the estimates of equity duration. The author found no evidence to support the stated hypotheses, when employing the Fama and French's three factor model. This may mean that the relationships are subsumed in the Fama and French risk factors.
AFRIKAANSE OPSOMMING: Hierdie werkstuk bestudeer die konsep van die duur van gewone aandele (equity duration), waar die duur van 'n gewone aandeel gedefinieer word as 'n maatstaf van die rentekoerssensitiwiteit van die markwaarde van die aandeel. Die tradisionele gebruik van standaard dividend verdiskonterings modelle, lei tot uiters lang duur beramings vir gewone aandele - in die orde van 10 jaar vir inkomste aandele tot 25 jaar en meer vir groei ondernemings wie se kontantvloei nie verwag word om te materialiseer voor 'n sekere toekomstige datum nie. Leibowitz (1986) identifiseer 'n alternatiewe empiriese benadering vir die beraming van gewone aandeel duur. Hierdie empiriese bepaling van die sensitiwiteit van die werklike aandeelprys tot onderliggende veranderings in rentekoerse, impliseer dat gewone aandele reageer asof hulle baie korter duur instrumente is. Verskeie pogings is aangewend om die verskille tussen teoretiese voorspellings van gewone aandeel-duur en empiriese bevindings te rekonsilieer. Die verskille tussen duur van bates in plek en groei-geleenthede word aangevoer as 'n moontlike rede vir bogenoemde verskille. Dit word geargumenteer dat investeringsgeleenthede soortgelyk is aan die opsies wat 'n onderneming het. Hierdie opsie-soortgelyke eienskappe van groei-geleenthede kan die basiese verhouding tussen gewone aandeel waardasie en rentekoers verandering wysig. Die opsie raamwerk dui daarop dat die duur van groei-ondernemings korter kan wees (en nie langer nie) as die van bates in plek. Die resultate van opsie teorie kan egter nie direk toegepas word op groei-opsies nie, aangesien sekere van die aannames nie geldig mag wees in die geval van groei-opsies nie. Die teenwoordigheid van hierdie groei-opsies het tot gevolg dat dit feitlik onmoontlik is om gewone aandeel-duur teoreties te bereken. Die studie toets empiries die verhouding tussen groei-geleenthede en gewone aandeel-duur deur te fokus op die rentekoers sensitiwiteit van Suid Afrikaanse groei-ondernemings. Die volgende hipoteses met betrekking tot die gewone aandele duur en groei-ondernemings word gestel: • Daar is 'n betekenisvolle verskil in rentekoers sensitiwiteit tussen groei-ondernemings en lae groei-ondernemings. • Daar is 'n betekenisvolle verskil tussen duur van groei-ondernemings gemeet deur gebruik te maak van nominale rentekoerse en duur van groei-ondernemings deur gebruik te maak van reële rentekoerse. Alle nie-myn ondernemings op die Johannesburg Sekuriteite Beurs SA, vir die periode 1980 tot 2000, is ontleed. Hierdie ondernemings is gesorteer in verskillende portefeuljes wat hulle groei geleenthede reflekteer. Markkapitalisasie, boek-tot-markwaarde en prysverdienste verhoudings is gebruik as maatstawwe om ondernemings te rangskik volgens groeigeleenthede. Die resultate van enkel veranderlike regressies dui positiewe duur aan vir gewone aandele. Die negatiewe verhouding tussen aandeelopbrengs en verandering in nominale rentekoerse is onafhanklik van grootte, boek-tot-markwaarde of prysverdienste verhoudings vir die getoetste ondernemings. Indien die markfaktor ingesluit word, as 'n onafhanklike veranderlike, lei dit tot opvallend verskillende gewone aandeel-duur. Die duur is gekorreleer met grootte, met beide koëffisiënte en t-statistieke wat styg wanneer beweeg word van klein ondernemings tot groter ondernemings. Addisioneel, die klein ondernemings het negatiewe, nie positiewe duur, anders as in die geval van eenvoudige enkel veranderlike regressies. Daar is ook bewyse dat hoë groei portefeuljes, soos gemeet deur lae boek-tot-markwaarde en hoë prysverdienste verhoudings, minder sensitief is vir rentekoers veranderings as lae groei portefeuljes. Met die aanwending van al drie Fama en French se faktore is daar nie meer kruis-selektiewe afhanklikheid (cross-selectional dependence) op ondernemingsgrootte aanwesig nie, met die gemiddelde duur wat naby nul is en statisties onbedeidend in feitlik all gevalle is. Wanneer die verandering in die nominale rentekoers verdeel word in veranderings in reële koerse en veranderings in inflasie, beïnvloed dit ook nie betekenisvol die bepaalde gewone aandeel duur nie. Die outeur het met die gebruik van die Fama & French drie faktor model geen bewyse gevind wat die vermelde hipoteses staaf nie. Dit mag beteken dat die rente-risiko verwantskappe in die Fama en French risiko faktore vervat is.

The aim of my thesis is an assessment of market value of a chosen company as of December 31, 2010. The appraisal was proceeded both by assumption of going concern and by assumption of limited duration of the company (in relation to prognosis of depletion of oil reserves).

Master of Science
Department of Clinical Sciences
Amy Rankin
Objective- The purpose was to compare the efficacy and duration of 0.5% proparacaine, 0.5% bupivacaine, 2% lidocaine, and 2% mepivacaine on corneal sensitivity in clinically normal horses. Animals- 68 clinically normal horses Procedures- In group 1, 60 horses from the Kansas State University horse unit were assigned to receive one topical anesthetic in a completely randomized design. In group 2, 8 privately owned horses were sequentially treated with each of the topical anesthetics in random order with a one week washout period between drugs. Corneal sensitivity was assessed by corneal touch threshold (CTT) measurements which were taken with a Cochet-Bonnet aesthesiometer before anesthetic application (T0), 1 minute after (T1), every 5 minutes until 60 minutes (T5-T60), and then every 10 minutes until 90 minutes (T70-T90) after application. General linear mixed models were fitted to CTT in each design in order to assess the effects of topical anesthetics over time, accounting for repeated observations within individual horses. Results- Corneal sensitivity, as determined by CTT measurements, decreased immediately following application of the topical anesthetic, with persisting effects until T35 for proparacaine and mepivacaine, T45 for lidocaine, and T60 for bupivacaine. Maximal CTT reduction was achieved following application of bupivacaine or proparacaine, while mepivacaine was least effective. Conclusions and Clinical Relevance- All topical anesthetics reduced corneal sensitivity, though maximal anesthesia and effect of duration differed between drugs. For brief corneal anesthesia, 0.5% proparacaine or 2% lidocaine appeared adequate, while 0.5% bupivacaine may be most appropriate for procedures requiring longer periods of corneal anesthesia.

BACKGROUND: Breastfeeding and lactation are cited as sensitive periods in the life course that contribute to the accumulation of risks or opportunities ultimately shaping vulnerability or resilience later in life. As such, breastfeeding and lactation are critical components of health equity. Despite this, Black women in the U.S. initiate and continue to breastfeed at lower rates than White women and other groups. Underlying reasons for racial inequities in breastfeeding rates are poorly understood. Exposure to racism, one manifestation of historical oppression in the U.S. has been cited as a determinant of poor health outcomes for decades but has not been extensively described in the context of breastfeeding. AIMS: To investigate the association between experiences of racism and 1.) breastfeeding initiation 2.) breastfeeding duration 3.) and the association between selected life-course factors and breastfeeding initiation and duration among participants of the Black Women’s Health Study. METHODS: This study was a prospective secondary analysis of the Black Women’s Health Study. The sample included all participants who enrolled in 1995, responded to the racism assessment in 1997 and reported the birth of a first child following the racism assessment resulting in an N=2, 995 for the initiation outcome and N= 2,392 for the duration outcome. In addition to the racism assessment, we also included life-course factors (nativity, neighborhood segregation and social mobility). For each aim, we calculated odds ratios and 95% confidence intervals using binomial and multinomial logistic regression using two models. The first adjusted for age, the second adjusted for age, BMI, education, marital status, geographic region, neighborhood SES and occupation. RESULTS: Associations between daily and institutional summary racism variables and breastfeeding initiation and duration were small and not statistically significant. Experiences of racism in the job setting was associated with lower odds of breastfeeding duration at 3-5 months compared with 3 months 95% CI [0.60, 0.98]. Experiences of racism with the police was associated with higher odds of breastfeeding initiation and duration at 3-5 months [1.01, 1.77] and at 6 months [1.10, 1.82] compared with women who did not report this experience. The participant’s nativity and the nativity of her parents were life-course factors that predicted lower odds of breastfeeding initiation and duration. Neighborhood segregation did not reach statistical significance after adjusting for covariates but results trended toward lower odds of breastfeeding initiation and duration for women who reported living in a predominately Black neighborhood (compared with White) up to age 18 and for women who reported living in a predominately Black neighborhood in 1999. CONCLUSION: Experiences of institutional racism in the job setting was associated with lower odds of breastfeeding duration. In addition to explicit experiences of racism, this study provides preliminary evidence surrounding life-course factors and breastfeeding. Individual level interventions may mitigate harmful effects of racism but structural level interventions are critical to close the gap of racial inequity in breastfeeding rates in the U.S.

Objective: To evaluate the association between shift work and blood pressure, pre-hypertension and hypertension in nursing personnel of a large general hospital. Methods: In a cross-sectional survey, 493 nurses, nurse technicians and assistants, were selected at random in a large general hospital. Hypertension was diagnosed by the mean of four automatic blood pressure readings>= 140/90 mmHg or use of blood pressure lowering agents, and pre-hypertension by systolic blood pressure>= 120-139 or diastolic blood pressure>= 80-89 mmHg. Risk factors for hypertension were evaluated by a standardized questionnaire and anthropometric measurements. The association between turns of work, defined as day or night, and by the combination of turns, and blood pressure, pre-hypertension and hypertension was explored in bivariate and multivariate analyses, controlling for risk factors for hypertension by covariance analysis and modified regression Poisson. Results: The mean age of the participants was 34.3 ± 9.4 years and 88.2% were women. Night shift workers were older, more frequently married or divorced, and less educated. The prevalence of hypertension in the whole sample was 16%, and 28% had pre-hypertension. Blood pressure (after adjustment for confounding) was not different in day and night shift workers. The prevalence of hypertension and pre-hypertension by shift work (day/night and combination of turns) was not different in the bivariate analysis and after adjustment for confounding (all risk ratios = 1.0). Conclusion: Night shift work is not associated with blood pressure, hypertension and pre-hypertension in nurses and nurses assistants working in a large general hospital.

碩士
國立高雄第一科技大學
財務管理所
93
This paper investigates the relationship between equity duration and the return of stock portfolio. The stocks listing on the Taiwan Sock Exchange (TSE) in the period between 1992~2003 are chosen for our study. At first, we adopt the B/M (book value to market value), MV/NTA (market value to net tangible assets), and P/E (price to earning per share) to determine the high、middle and low growth stock portfolio. After calculating the portfolio return and including nominal interest rate, real interest rate, inflation rate, the weighted stock market index, and the orthogonalized index, an multiple regression model is used to estimated the regression coefficient, a proxy for portfolio equity duration. And we further examine whether there is significant difference in equity duration from the two portfolios. The empirical evidences support two conclusions. First, we find that the high, middle, and low growth stock portfolio (B/M,MV/NTA)are all positive correlative sensitivity to the interest rate fluctuation, no matter in the full period(1992~2003 years) or the long-time interest stability period(1992~1999 years). Besides, the sensitivity of correlation is presented in an order of their size. That is that the high growth stock portfolio is more significant sensitive to interest changes at 5% significant level and the equity duration is larger; while the low growth stock portfolio is not sensitive to the change of interest rates. However, the stock portfolio of P/E doesn’t have this characteristics. On the other hand, the interest rate sensitivities to the return of the high and low growth stock portfolio(B/M,MV/NTA) have significant difference; but isn’t different between the P/E stock portfolios. Secondly, except the collinearity of the weighted stock market index and the interest rate, the return of the three growth stock portfolio (B/M、MV/NTA、P/E) all have negative correlative sensitivity to the interest rate fluctuation in the long-time interest rate drop period(2000~2003 years). Besides, the high growth stock portfolio has more significant sensitivity. However, there is no significant different between the equity durations of the high growth stock portfolio and the low growth stock portfolio.

碩士
銘傳大學
經濟學系碩士班
94
In past, all the researches about banking interest rate risk to measure the effect of interest rate fluctuation on banking industries asset value were base on banking visions. This study use the stock investors views to see the financial storm of Asia in 1997 till to established financial holding companies in 2000 . We used the equity duration to search the effect of the interest rate fluctuation on banking industries stocks price. And know how the investors to face the price risk. In order to explore the bank price risk that investors faced were involved structural change by Taiwan banking industries equity duration changes. From the first empirical target, Taiwan banking equity duration in 1997, the financial storm of Asia was decrease. That was showed the banking investor’s price risk was not increased. But, in 2000 the financial holding company established the result of the empirical was contrary. That were exhibit after the financial holding company established the risk of stock price was increased. This study was on second thought to analyze the main factor of equity duration. We were seen that banking industries growth opportunity and risk control were the main factors to influence the banking industries equity duration.

This chapter discusses the manner in which leases can be transferred or assigned. Leases constitute an important exception to the general rule that burdens cannot be assigned. The assignment of any lease, no matter what its duration, must be effected formally by deed. This is so even where the lease could have been created informally. Additionally, so far as leases of over seven years are concerned, the transfer must be registered in order to be effective. There is a fundamental distinction between a legal and an equitable lease. A legal lease comes into being when the requisite formalities for the creation of such a lease have been complied with. Meanwhile, an equitable lease comes into being when, although the requisite formalities have not been complied with, there is nevertheless a contract for a lease to which equity will give effect.

AbstractBatch runs corresponding to the same recipe usually have different duration. The data collected by the sensors that equip batch production lines reflects this fact: time series with different lengths and unsynchronized events. Dynamic Time Warping (DTW) is an algorithm successfully used, in batch monitoring too, to synchronize and map to a standard time axis two series, an action called alignment. The online alignment of running batches, although interesting, gives no information on the remaining time frame of the batch, such as its total runtime, or time-to-end. We notice that this problem is similar to the one addressed by Survival Analysis (SA), a statistical technique of standard use in clinical studies to model time-to-event data. Machine Learning (ML) algorithms adapted to survival data exist, with increased predictive performance with respect to classical formulations. We apply a SA-ML-based system to the problem of predicting the time-to-end of a running batch, and show a new application of DTW. The information returned by openended DTW can be used to select relevant data samples for the SA-ML system, without negatively affecting the predictive performance and decreasing the computational cost with respect to the same SA-ML system that uses all the data available. We tested the system on a real-world dataset coming from a chemical plant.

Early intervention treatments and approaches are reaching across the globe. There is no doubt though that these services are a low priority, especially in countries where adequate resources are not available. The practice of psychiatry has, in the last 50 years, moved from asylums, to community mental-health teams, to home treatments and early intervention. There appears to be an increasing body of evidence to suggest that early interventions can work in reducing the duration of untreated illness and aiding better recovery, but this needs to be researched in conditions other than psychoses, for which evidence is strong. This chapter provides recommendations for researchers, clinicians, and policymakers. All these recommendations are based on the principle of equity between physical and mental illness, and better integration between psychiatric services and social care and between primary care and psychiatric services.

This paper looks at banking following the way of thinking of J.A. Schumpeter and F. Besta, and addresses two main points: a) the idea that ‘loans make deposits’, as opposed to the popular view that ‘deposits make loans’, and b) the poor quality of information on banking performance delivered by double-entry bookkeeping, following either the equity-centered accounting system (‘sistema patrimoniale’) or the Zappa’s profit-centered accounting system (‘sistema del reddito’). The most important problems of banking, indeed, are loan liquidity and solvency, which are difficult to evaluate from the balance sheet items, so that additional information is needed from outside the balance sheet to evaluate, for example, maturities and durations. This critical point implies that the risk taker is CET1 and not savers, as the Basel Committee stated.

The needs to discipline and train prisoners for work, has become a convention that all nations including Ghana have come to accept with a view to churning out productive ex-prisoners. Thus, the aim prison education programs in Ghana is to turn inmates into useful citizens and the purpose of vocational training is to equip prisoners with skills which they can utilize to make a living. Additionally, the purpose for setting up the Junior and Senior High Schools is to give a second chance to inmates who dropped out of school before they were incarcerated. Similarly, the functional literacy program was introduced to teach illiterate prisoners how to read and write English, Akan, Ga, and Ewe languages. The chapter also discusses the duration, enrollment, teachers and the challenges of the programs. In addition, the general education program focuses on the curriculum, examination, and class attendance. The themes covered provide information on how prisoners are prepared toward reintegration in Ghana.

Bridging the gender diversity gap has become a key KPI for most organizations today. Diversity teams are constantly planning interventions to recruit and retain women in the workforce to increase their representation. One of the most common interventions is to provide women with training to equip them with the necessary skills and competencies (e.g., career management, social, management, and leadership) to stay and grow in their careers. Corporates today are relying on online learning to offer these training programs for cost-effective, flexible, and long-duration learning. However, there is a lack of guidelines for the successful implementation of online women training programs. This study aims to provide a framework to guide the planning and implementation of these programs. The framework is arrived at based on insights and best practices from a leading Online University that offers women training programs in India and south Africa. Participant feedback from the programs and participant perceptions on online training programs are also used to further refine framework.

Bridging the gender diversity gap has become a key KPI for most organizations today. Diversity teams are constantly planning interventions to recruit and retain women in the workforce to increase their representation. One of the most common interventions is to provide women with training to equip them with the necessary skills and competencies (e.g., career management, social, management, and leadership) to stay and grow in their careers. Corporates today are relying on online learning to offer these training programs for cost-effective, flexible, and long-duration learning. However, there is a lack of guidelines for the successful implementation of online women training programs. This study aims to provide a framework to guide the planning and implementation of these programs. The framework is arrived at based on insights and best practices from a leading Online University that offers women training programs in India and south Africa. Participant feedback from the programs and participant perceptions on online training programs are also used to further refine framework.

"The fourth National Climate Assessment warns of increases in the intensity and duration of precipitation events in the coming decades, leading to a greater severity and frequency of flash floods in portions of the United States. This concern is exacerbated by a national trend in deteriorating stormwater infrastructure and increased urbanization with densification of impervious land cover. In coastal cities with accelerated development, surge events overwhelm infrastructure that was not expanded with changes in land cover. In older cities with combined sewer systems, floods result in outflows of raw sewage into ecological zones. In sprawling cities with extreme seasonal storms, a historic failure to invest in infrastructure during periods of growth causes significant, annual property damage. The damages will worsen with the projected increases in extreme precipitation if innovations are not made. However, municipalities also face resource constraints. Under limited budgets governments increasingly are asked to monitor, prevent, and respond to the impacts of climate change. Is there another answer to urban flooding than massive, top-down, and single-purpose public works? Can municipalities instead address urban challenges with a new paradigm: decentralized, bottom-up, and multi-benefit infrastructure?"

Abstract In this work, we use structural topology optimization to design the hip bone with multi-load conditions of walking gait cycle. Previous research works on optimal bone design primarily aimed to design the micro-structure of the femur bone using a multi-load approach with global geometry fixed. To the best of authors’ knowledge, no optimal design research literature is available on the hip bone. This work uses the concept of multiload conditions, since it considers the effect of entire gait cycle while applying loading conditions. We consider three cases for the weights. Those are (i) equi-weight case, (ii) non-equi weight case based on the fraction of the phase in the gait cycle and (iii) non-equi weight case based on the ratio of magnitude of the hip joint force in respective phases to the total hip joint force of the entire walking gait cycle. The optimal designs are compared with natural hip bone by measuring shape similarity using Procrustes Analysis. Results show that the compliance is less for the optimal designs compared with natural hip bone. The shape similarity values for the three cases are found to be 64%, 78% and 73% respectively. Optimal design obtained from the non-equi weight case based on the duration of phase has highest shape similarity value due to creation of a hole similar to obturator foramen in lower portion of the hip bone. The maximum stress and maximum displacement values are lower in optimal designs compared with natural hip bone. From the shape similarity results, the optimal design from the non-equi weight based on duration of the phase may be more suitable for prosthesis applications.

In the application of random vibration testing and the inverse power law to test products and extrapolate equivalent field life, the shape of the Power Spectral Density (PSD) vibration curve frequently introduces prediction errors and increased testing. A field PSD profile found to be highly dissimilar in shape to that used in the original accelerated testing raises questions of how to extrapolate equivalent life and often results in the need to repeat long duration vibration testing. Past work by the author has proposed utilizing the evaluation of zero crossings in two dissimilar PSD curves as a way to equate their testing impact and life predictions and therefore not require re-testing. This paper expands on this theory and explores utilization of spectral moments and Dirlik’s damage model to compare dissimilar PSD curves. Finite Element Analysis (FEA) and other analytical methods are utilized to expose a mechanical system to vibration inputs of different shapes, compute their fatigue life and then evaluate spectral moments and Dirlik’s damage model’s ability to account for dissimilar PSD curves.

Inflatable life rafts are currently used on almost all passenger, fishing and commercial vessels, and offshore oil installations. Worldwide, life rafts are the primary evacuation system from fishing vessels with relatively small crews to large Roll on/Roll off passenger vessels with over a thousand passengers and crew. While International Maritime Organization (IMO) standards currently require inflatable life raft components to “provide insulation” or “be sufficiently insulated”, there are no performance criteria for these requirements (IMO, 1996). In a passenger ship abandonment situation in cold water, passengers may be wearing very little personal protective clothing. Therefore, life rafts provide the only significant thermal protection against the cold ocean environment while they await rescue. Manufacturers equip life rafts with an insulated floor to reduce heat loss from direct contact with the cold ocean water. The insulation provided is critically important for life raft occupants who have little protective clothing. The heat loss of unprotected persons is drastically increased if there is a layer of water on the floor as would likely be the case when someone climbs into the life raft from the ocean or if water is splashed into the life raft in heavy weather. Experiments were conducted in mild cold (16°C water temperature and 19°C air temperature) and cold conditions (5°C water temperature and 5°C air temperature) to assess the thermal protection of a 16-person, Safety of Life at Sea (SOLAS) approved, commercially available life raft. This paper presents results in the mild cold condition only. It has been found that the wave height effect may be ignored as a first approximation to reduce the number of environmental variables because the results demonstrated that wave height effect is less important with leeway. Heat conductance decreases considerably with floor inflation. Heat conductance is about the same with floor inflated 50% and 100%. The CO2 concentration in the 11-person test exceeded 5000 ppm in less than an hour inside the life raft, with closed canopy and no active ventilation. This hostile microclimate inside the life raft suggests that active ventilation at a known rate is required to keep the CO2 level at a safe controlled level when longer duration tests are to be conducted in the future. Wet clothing has a significant effect on occupant heat loss.