The forward market for foreign exchange :

The findings of this study support others which examine financial markets. The time series distributions are not normal; they are stable Paretian. The forward market for foreign exchange is not random; but neither is it inefficient based on the weak form model.The study also shows that there were patterns in the time series of rates of return on forward contracts. These were low level autocorrelations and were not stable through time. The patterns were short and changed throughout the time period. Using several testing techniques, the hypothesis that the forward is inefficient was rejected. Several nonparametric tests and Box-Jenkins time series analysis were used. These show that the time series of rates of return on forward contracts, while not a random walk, are not inefficient at the weak form level.Intertemporal speculation, the act of speculating between forward maturities, was defined in the paper. The existence of profitability using this technique was found to be significantly different from zero, but less than the return on short-term U. S. government securities. Therefore, even though the technique is available for forward market participants, the return is not commensurate with the level of risk incurred.The study employed daily spot and forward exchange rates from March 1973 to June 1976 for the following currencies: U.S. to U.K.; U.S. to Swiss Franc; U.S. to German Mark; U.S. to Canadian Dollar; U.K. to German Mark; and U.K. to Canadian Dollar. The rate of return on forward contracts was defined to be the difference between the forward rate at time t and the spot rate which exists upon maturation of that forward contract expressed as a percentage of the spot rate. The distribution of these rates of return was shown to more closely approximate the stable Paretian distribution than the normal distribution. This was true for the spot rate and forward rate distributions as well. Since stable Paretian distributions have no defined variance, an alternative measure of disbursion should be established to replace the sample standard deviation or variance.This study is devoted to an examination of the efficiency and characteristics of the forward market for foreign exchange. Here, efficiency implies that current market prices or rates incorporate any information embodied in the pattern of past prices or rates. The characteristics of the forward market examined include the distribution of rates of return, as well as the relationship of forward exchange rates of different maturities.The percentage premia of different forward rates, relative to the spot rate, were examined in the paper. It was found that relative premia decline as time to maturity increases. Furthermore, the premia decrease at a decreasing rate. The slope between 30 and 60 day premia is more steep than the slope between 60 and 90 day premia. For firms using the forward market to cover exchange rate risk, the implication is that the cost of forward cover is decreased as forward maturity is increased. Thus a reward exists for good forward planning

Bryophyte and lichen biomass and nitrogen fixation in a high elevation cloud forest in Cerro de La Muerte, Costa Rica

Cloud forests have been found to lose more nitrogen in stream discharge than they gain from atmospheric deposition. They also support a large diversity and biomass of tree epiphytes, predominately composed of cryptogams. Since cryptogam epiphytes harbor nitrogen fixing cyanobacteria, they may help make up for the nitrogen loss from ecosystems. We assessed cryptogam biomass on the ground, boles and branches in Quercus costaricensis dominated stands near the tree line in the Cordillera de Talamanca, Costa Rica. Nitrogen fixation was assayed using 15N2 uptake. Total cryptogam biomass was 2 977 kg ha−1, with 67% being found on the lower branches. Bryophytes and chlorolichens made up 53% and 44%, respec- tively, of the biomass. Half of the bryophyte mass was composed of the liverwort Plagiochila heterophylla, and 66% of the chlorolichen of Lobariella pallida. There were no significant differences in nitrogen fixation rates between the cryptogam species, with a mean rate of 5.04 µg N g−1 day−1 during the predominantly wet condition in the forest. The overall nitrogen input from fixation was 6.1 kg N ha−1 year−1, of which 78% came from bryophytes, 18% from chlorolichens, and 4% from cyanolichens. Only 2.0% of the fixation occurred in cryptogams on the ground, whereas 67%, 24%, and 7% occurred on the lower branches, boles, and upper branches, respectively. These results show that tree epiphytes constitute a significant source of nitrogen for these forests, due to the trees’ large surface area, and can make up for the nitrogen lost from these ecosystemsUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de BiologíaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biodiversidad y Ecología Tropical (CIBET

New directions in Indigenous service population estimation

Accurate assessments of the number of people who access goods or services in a particular location are crucial to the equitable allocation of resources and the delivery of services. In particular, Indigenous Australians are an important subpopulation for whom such estimates would be useful, given the high levels of Indigenous temporary mobility. We review previous estimates of service populations relevant to Indigenous Australians and find that there is no currently accepted method for quantification. We argue that any attempt to develop a single measure of service populations for all services at a place is likely to meet only limited success. Instead, we propose that service populations should be estimated on a service-by-service basis. We then give a hypothetical example of how the Indigenous service populations of hospitals might be estimated using existing administrative data and a geographical approach. We conclude by arguing that access to key datasets remains the most important barrier to the estimation of Indigenous service populations

Deployment and testing of a second prototype expandable surgical chamber in microgravity

During microgravity exposure, two separate expandable surgical chambers were tested. Both chambers had been modified to fit the microgravity work station without extending over the sides of the table. Both chambers were attached to a portable laminar flow generator which served two purposes: to keep the chambers expanded during use; and to provide an operative area environment free of contamination. During the tests, the chambers were placed on various parts of a total body moulage to simulate management of several types of trauma. The tests consisted of cleansing contusions, debridement of burns, and suturing of lacerations. Also, indigo carmine dye was deliberately injected into the chamber during the tests to determine the ease of cleansing the chamber walls after contamination by escaping fluids. Upon completion of the tests, the expandable surgical chambers were deflated, folded, and placed in a flattened state back into their original containers for storage and later disposal. Results are briefly discussed

A review of the bopyrid isopods infesting caridean shrimps in the northwestern Atlantic Ocean, with special reference to those collected during the Hourglass Cruises in the Gulf of Mexico

(156pp.

Autonomous learning for face recognition in the wild via ambient wireless cues

Facial recognition is a key enabling component for emerging Internet of Things (IoT) services such as smart homes or responsive offices. Through the use of deep neural networks, facial recognition has achieved excellent performance. However, this is only possibly when trained with hundreds of images of each user in different viewing and lighting conditions. Clearly, this level of effort in enrolment and labelling is impossible for wide-spread deployment and adoption. Inspired by the fact that most people carry smart wireless devices with them, e.g. smartphones, we propose to use this wireless identifier as a supervisory label. This allows us to curate a dataset of facial images that are unique to a certain domain e.g. a set of people in a particular office. This custom corpus can then be used to finetune existing pre-trained models e.g. FaceNet. However, due to the vagaries of wireless propagation in buildings, the supervisory labels are noisy and weak. We propose a novel technique, AutoTune, which learns and refines the association between a face and wireless identifier over time, by increasing the inter-cluster separation and minimizing the intra-cluster distance. Through extensive experiments with multiple users on two sites, we demonstrate the ability of AutoTune to design an environment-specific, continually evolving facial recognition system with entirely no user effort

Triple wavelength LED driver for optical brain–computer interfaces

A dedicated triple wavelength LED driver is presented for optical brain–computer interfacing (BCI). The solution caters for the constraints of a common-anode grounded case and modulation up to several kilohertz that allows source separation of light that has backscattered from the brain. With total harmonic distortion of 0.95% and a frequency range of ~40 kHz, the driver has application in a continuous wave optical BCI. Other modulation strategies such as time division multiplexing (TDM) are catered for, owing to input DC coupling. Linearity in the optical output is maintained by the ‘load sensing’ differential op-amp on the LED’s current limiting resistor, which is the basis for the V-I conversion

Triple wavelength LED driver for optical brain–computer interfaces

A dedicated triple wavelength LED driver is presented for optical brain–computer interfacing (BCI). The solution caters for the constraints of a common-anode grounded case and modulation up to several kilohertz that allows source separation of light that has backscattered from the brain. With total harmonic distortion of 0.95% and a frequency range of ~40 kHz, the driver has application in a continuous wave optical BCI. Other modulation strategies such as time division multiplexing (TDM) are catered for, owing to input DC coupling. Linearity in the optical output is maintained by the ‘load sensing’ differential op-amp on the LED’s current limiting resistor, which is the basis for the V-I conversion

Optical Safety Assessment of a Near-Infrared Brain-Computer Interface

This paper describes a safety assessment study of near-infrared sources used in an optical brain-computer interface (BCI). The measurement elements of an optical BCI consist of sets of optical sources and detectors. Our current system utilises sources which comprise of dual wavelength light emitting diodes (LED) at 760nm and 880nm. An optical analysis demonstrated that NIR radiation is a negligible source of heating in this case. LED heat conduction however is a major source of heating, and LEDs, though much safer than laser diodes, have been known to cause burns if improperly used. We describe a procedure by which we measure the heat conduction effect of LEDs. We show that the LED systems used in our current generation BCI produce safe levels of thermal energy and are within published safety levels