The Use of Subcarriers in Future DSN Missions

The performance of deep space telemetry signals that employ a residual carrier modulation technique is compared in the presence and absence of a subcarrier. When the subcarrier is present, the performance for the resulting pulse-coded modulation/phase-shift keyed/phase-modulated (PCM/PSK/PM) scheme is evaluated for both sine wave and square wave subcarriers and non-return-to zero (NRZ) data. When the subcarrier is absent, the performance for the resulting PCM/PM technique is evaluated for both the NRZ and the bi-phase data format. The comparison is based on telemetry performance as well as bandwidth efficiency. The first criterion is characterized in terms of the symbol error rate (SER) as a function of symbol SNR, loop bandwidth-to-data rate ratio, and modulation index. The bandwidth efficiency is characterized by the occupancy factor. The results of both the analysis and measurements show that when the interference-to-carrier ratio (ICR) is less than -15 dB, the performance degradation in the absence of a subcarrier is negligible. Various combinations of loop bandwidth-to-data rate ratios and modulation indices that achieve this performance are derived and listed. Bandwidth occupancy comparison indicates that PCM/PM/NRZ is the most efficient in this regard. Therefore, by eliminating the subcarrier and using the PCM/PM/NRZ scheme, many advantages can be realized without any sacrifice in performance

Real-time edge-enhanced optical correlator

The performance of five symbol lock detectors are compared. They are the square-law detector with overlapping (SQOD) and non-overlapping (SQNOD) integrators, the absolute value detectors with overlapping and non-overlapping (AVNOD) integrators and the signal power estimator detector (SPED). The analysis considers various scenarios when the observation interval is much larger or equal to the symbol synchronizer loop bandwidth, which has not been considered in previous analyses. Also, the case of threshold setting in the absence of signal is considered. It is shown that the SQOD outperforms all others when the threshold is set in the presence of signal, independent of the relationship between loop bandwidth and observation period. On the other hand, the SPED outperforms all others when the threshold is set in the presence of noise only

Inventing New Modes of Dissemination: Applied Preservation and Cultural Heritage Pedagogy in Interdisciplinary Studios

When we shift the word practice from noun to verb, practice turns into testing, experimenting with what is at hand. If we then apply this performative approach to the practice of teaching preservation and cultural heritage in a design studio setting, what would be the consequences? What would happen if we consider teaching as a practice of research and, consequently, of research as experimentation in a field that inherently resists innovation of practice? Two professors, one from architecture, the other from interior design, offer preliminary answers to these questions while also laying out a model for a new critical pedagogy built on an interdisciplinary practice of teaching in which students from architecture, interior design, and landscape architectrue have to address their own position within the context of a new studio while confronting a new language, i.e. that of the other discipline. In this study we analyze two interdisciplinary studios we co-taught in 2017 and 2018 as case studies for applied history and the production of culture through our collaboration with the US Department of State's Overseas Building Operations office in Cultural Heritage. In these research-based, interdisciplinary design studios we were tasked by the State Department to develop new methodologies of documenting and disseminating via websites information about two historic properties abroad, the Winfield House (London) and the Villa Petschek (Prague), both historically significant American Ambassadors' Residences. Our work resulted in a body of research that emerged out of applied onsite field work combined with analytic methods, archival investigations, and interdisciplinary communication to create a holistic understanding of the role historic properties abroad can play in the production of culture within an academic environment that is linked through current technology to society at large

Funding and Forming New Interdisciplinary Collaborations: The Development of Iowa State University\u27s Masters Program in Historic Preservation

For the past two years, five departments in ISU’s College of Design collaborated with the University’s Provost, the College’s Dean, Iowa businesses, and Iowa’s Main Street program to visualize and finance an interdisciplinary masters program in Historic Preservation. With the first phase of implementation complete this breakout session reviews a study that examines 1) how university programs in the arts and applied arts can collaborate with regional businesses and existing governmental agencies to secure external funding and 2) the key characteristics and essential strategies of a successful interdisciplinary and cross disciplinary collaboration

Putting the Power of Configuration in the Hands of the Users

Goal was to reduce the overall cost of human space flight while maintaining the most demanding standards for safety and mission success. In support of this goal, a project team was chartered to replace 18 legacy Space Shuttle nonconformance processes and systems with one fully integrated system Problem Reporting and Corrective Action (PRACA) processes provide a closed-loop system for the identification, disposition, resolution, closure, and reporting of all Space Shuttle hardware/software problems PRACA processes are integrated throughout the Space Shuttle organizational processes and are critical to assuring a safe and successful program Primary Project Objectives Develop a fully integrated system that provides an automated workflow with electronic signatures Support multiple NASA programs and contracts with a single "system" architecture Define standard processes, implement best practices, and minimize process variation

SCHIZOPHRENIA SPECTRUM PSYCHOSIS IN A CROATIAN GENETIC ISOLATE: GENEALOGICAL RECONSTRUCTIONS

Background: Schizophrenia spectrum psychosis is a chronic mental disorder, based on a range of genes whose expression can be altered by different environmental factors. Subjects and methods: In this archival and demographic study of genetic isolate we show an incidence of schizophrenia spectrum psychosis in a minority population and transmission of schizophrenia spectrum psychosis through several generations of two families in an isolated rural area of Dalmatia from the second half of 19th and the first half of 20th century. Results: The incidence of schizophrenia spectrum psychosis was between 0.58 and 2.58 per 1000 inhabitants. The genogram of Family 1 shows that out of 182 descendants in six generations, there were 27 people with schizophrenia spectrum psychosis. Schizophrenia spectrum psychosis occurred in two men who were born from a relationship of a mother with her relative. The genogram of Family 2 shows that 19 out of 86 descendants in five generations suffered from schizophreniform psychosis. Conclusion: The high occurrence of schizophrenia spectrum psychosis in an isolated village in central Dalmatia is in accordance with the results of earlier studies in that region. The fact that psychosis occurs in varying frequency, without obvious regularity, can be explained by the irregular expression of risk genes as well as by exogenous factors which may affect the activity of the key chromosome areas. Occurrence of psychosis in people born from incestuous relationships indicates the importance of genetic factors in the development of the disorder

Symbol lock detection implemented with nonoverlapping integration intervals

A symbol lock detector is introduced for an incoming coherent digital communication signal which utilizes a subcarrier modulated with binary symbol data, d(sub k), and known symbol interval T by integrating binary values of the signal over nonoverlapping first and second intervals selected to be T/2, delaying the first integral an interval T/2, and either summing or multiplying the second integral with the first one that preceded it to form a value X(sub k). That value is then averaged over a number M of symbol intervals to produce a static value Y. A symbol lock decision can then be made when the static value Y exceeds a threshold level delta

Residual and suppressed-carrier arraying techniques for deep-space communications

Three techniques that use carrier information from multiple antennas to enhance carrier acquisition and tracking are presented. These techniques in combination with baseband combining are analyzed and simulated for residual and suppressed-carrier modulation. It is shown that the carrier arraying using a single carrier loop technique can acquire and track the carrier even when any single antenna in the array cannot do so by itself. The carrier aiding and carrier arraying using multiple carrier loop techniques, on the other hand, are shown to lock on the carrier only when one of the array elements has sufficient margin to acquire the carrier on its own

The polyethylene terephthalate water bottles problem in Dubai hotels—Would an initiative solve this problem or does it need a law?

This paper examines the environmental effects of polyethylene terephthalate (PET) water bottles used by tourists in Dubai. Unfortunately, tourists residing in Dubai hotels must depend on these single-use plastic water bottles that have negative environmental impacts associated with their production and disposal. Thus, the government of Dubai launched an initiative to reduce the usage of PET bottles, and this paper discusses whether this initiative is adequate to change hotels' dependence on PET water bottles. Therefore, this paper tries first to find the reasons that would drive hotels to comply with this initiative and then assesses the compliance of hotels with this initiative 1 year after its launch. It is found that pressures from hotels with the same and higher ratings are crucial drivers for hotels to replace PET bottles with other alternatives. Officials affiliated with the Dubai Can initiative confirmed these findings. They have also anticipated that UAE residents who spend their vacations in Dubai hotels will exert substantial pressure on hotels to abandon PET bottle use. Decision-makers affirmed that a good percentage of five-star hotels, in addition to several four-star hotels, have abolished the use of PET bottles. Moreover, it is anticipated that all hotels are expected to stop using PET bottles. Consequently, this study shows that promoting environmentally responsible behavior without enacting laws is possible