Digital signal processor
A digital signal processor is a specialized microprocessor, with its architecture optimized for the operational needs of digital signal processing. The goal of DSP is to measure, filter or compress continuous real-world analog signals. Most general-purpose microprocessors can execute digital signal processing algorithms but may not be able to keep up with such processing continuously in real-time. Dedicated DSPs have better power efficiency, thus they are more suitable in portable devices such as mobile phones because of power consumption constraints. DSPs use special memory architectures that are able to fetch multiple data or instructions at the same time. Digital signal processing algorithms require a large number of mathematical operations to be performed and on a series of data samples. Signals are converted from analog to digital, manipulated digitally, converted back to analog form. Many DSP applications have constraints on latency. Most general-purpose microprocessors and operating systems can execute DSP algorithms but are not suitable for use in portable devices such as mobile phones and PDAs because of power efficiency constraints.
A specialized digital signal processor, will tend to provide a lower-cost solution, with better performance, lower latency, no requirements for specialised cooling or large batteries. Such performance improvements have led to the introduction of digital signal processing in commercial communications satellites where hundreds or thousands of analog filters, frequency converters and so on are required to receive and process the uplinked signals and ready them for downlinking, can be replaced with specialised DSPs with a significant benefits to the satellites' weight, power consumption, complexity/cost of construction and flexibility of operation. For example, the SES-12 and SES-14 satellites from operator SES, both intended for launch in 2017, were built by Airbus Defence and Space with 25% of capacity using DSP; the architecture of a digital signal processor is optimized for digital signal processing. Most support some of the features as an applications processor or microcontroller, since signal processing is the only task of a system.
Some useful features for optimizing DSP algorithms are outlined below. By the standards of general-purpose processors, DSP instruction sets are highly irregular. Both traditional and DSP-optimized instruction sets are able to compute any arbitrary operation but an operation that might require multiple ARM or x86 instructions to compute might require only one instruction in a DSP optimized instruction set. One implication for software architecture is that hand-optimized assembly-code routines are packaged into libraries for re-use, instead of relying on advanced compiler technologies to handle essential algorithms. With modern compiler optimizations hand-optimized assembly code is more efficient and many common algorithms involved in DSP calculations are hand-written in order to take full advantage of the architectural optimizations. Multiply–accumulates operations used extensively in all kinds of matrix operations convolution for filtering dot product polynomial evaluation Fundamental DSP algorithms depend on multiply–accumulate performance FIR filters Fast Fourier transform Instructions to increase parallelism: SIMD VLIW superscalar architecture Specialized instructions for modulo addressing in ring buffers and bit-reversed addressing mode for FFT cross-referencing Digital signal processors sometimes use time-stationary encoding to simplify hardware and increase coding efficiency.
Multiple arithmetic units may require memory architectures to support several accesses per instruction cycle Special loop controls, such as architectural support for executing a few instruction words in a tight loop without overhead for instruction fetches or exit testing Saturation arithmetic, in which operations that produce overflows will accumulate at the maximum values that the register can hold rather than wrapping around. Sometimes various sticky bits operation modes are available. Fixed-point arithmetic is used to speed up arithmetic processing Single-cycle operations to increase the benefits of pipelining Floating-point unit integrated directly into the datapath Pipelined architecture Highly parallel multiplier–accumulators Hardware-controlled looping, to reduce or eliminate the overhead required for looping operations In engineering, hardware architecture refers to the identification of a system's physical components and their interrelationships; this description called a hardware design model, allows hardware designers to understand how their components fit into a system architecture and provides to software component designers important information needed for software development and integration.
Clear definition of a hardware architecture allows the various traditional engineering disciplines to work more together to develop and manufacture new machines and components. Hardware is als
Defense Support Program
The Defense Support Program is a program of the U. S. Air Force that operates the reconnaissance satellites which form the principal component of the Satellite Early Warning System used by the United States. DSP satellites, which are operated by the Air Force Space Command, detect missile or spacecraft launches and nuclear explosions using sensors that detect the infrared emissions from these intense sources of heat. During Desert Storm, for example, DSP was able to detect the launches of Iraqi Scud missiles and provide timely warnings to civilians and military forces in Israel and Saudi Arabia; the satellites are in geosynchronous orbits, are equipped with infrared sensors operating through a wide-angle Schmidt camera. The entire satellite spins so that the linear sensor array in the focal plane scans over the earth six times every minute. DSP satellites were launched on Titan IVB boosters with Inertial Upper Stages. However, at least one DSP satellite was launched using the Space Shuttle, the known example being Atlantis on mission STS-44.
The last known DSP satellite was launched in 2007 aboard the first operational flight of the Delta IV Heavy rocket, as the Titan IV had been retired in 2005. All 23 satellites were built by prime contractor Northrop Grumman Aerospace Systems TRW, in Redondo Beach, CA; the 460th Space Wing, with headquarters at Buckley Air Force Base, has units the 2d Space Warning Squadron, that operate DSP satellites and report warning information, via communications links, to the NORAD and USSTRATCOM early warning centers within the Cheyenne Mountain Complex, Colorado. These centers forward data to various agencies and areas of operations around the world. Air Force Space Command's SBIRS Wing at the Space and Missile Systems Center, Los Angeles AFB, California is responsible for development and acquisition of the satellites; the Defense Support Program replaced. The first successful launch of MiDAS was 24 May 1960 and there were twelve launches before the DSP program replaced it in 1966; the first launch of a DSP satellite was on 6 November 1970 and since it has become the mainstay of the United States ballistic missile early warning system.
For the last 40 years they have provided an uninterrupted space-based early warning capability. The original DSP satellite weighed 2,000 pounds and had 400 watts of power, 2,000 detectors and a design life of 1.25 years. Throughout the life of the program, the satellite design has undergone numerous improvements to enhance reliability and capability; the weight grew to 5,250 pounds, the power to 1,275 watts, the number of detectors increased threefold to 6,000 and the design life has been increased to a goal of five years. The numerous improvement projects have enabled DSP to provide accurate, reliable data in the face of evolving missile threats. On-station sensor reliability has provided uninterrupted service well past their design lifetime. Recent technological improvements in sensor design include above-the-horizon capability and improved resolution. Increased on-board signal-processing capability improves clutter rejection. Enhanced reliability and survivability improvements were incorporated.
The 23rd, last DSP satellite was scheduled to be launched on 1 April 2007, aboard a Delta IV Heavy rocket, but the launch was postponed until mid-August 2007 after two structural cracks were found in the metal launch table at pad 37B, caused by a fuel leak during testing. Further delays forced the launch back to 11 November 2007, when the satellite launched at 01:50:00 GMT; this satellite died in space for reasons unknown. It remains a potential hazard to other craft; the Department of Defense sent a MiTEx spacecraft to inspect DSP 23 sometime in 2008. Another DSP satellite was lost in 1999, after its Inertial Upper Stage failed following launch from a Titan 4 booster. DSP satellites will be replaced by the Space-Based Infrared System satellites; the project was to have had a life of 25 satellites, but the last two have been canceled due to SBIRS. There were five major improvement programs on the 13 satellites: Block 1: Phase I, 1970–1973, four satellites Block 2: Phase II, 1975–1977, three satellites Block 3: Multi-Orbit Satellite Performance Improvement Modification, 1979–1984, four satellites Block 4: Phase II Upgrade, 1984–1987, two satellites Block 5: DSP-I, 1989More there has been some effort put into using DSPs' infrared sensors as part of an early warning system for natural disasters like volcanic eruptions and forest fires.
The DSP constellation may have offered an excellent vantage point for an early warning system against state-centric threats such as missiles, but military analysts warn its ability to collect intelligence on non-state actors is limited. Primary mission: Strategic and tactical missile launch detection Contractor team: Northrop Grumman Aerospace Systems TRW and Northrop Grumman Electronic Systems Aerojet Electronics Systems Weight: 5,250 lb Orbit altitude: 22,000 miles Power plant: Solar arrays generate 1,485 watts Height: 32.8 ft on orbit.
Delta Sigma Phi
Delta Sigma Phi known as Delta Sig, is a national men's fraternity established in 1899 at The City College of New York. It was the first fraternity to be founded on the basis of ethnic acceptance, it is one of three fraternities founded at CCNY. Delta Sigma Phi is a charter member of the North-American Interfraternity Conference; the fraternity's national headquarters are located in Indianapolis, Indiana, at the Fairbanks Mansion, the former home of Charles Warren Fairbanks, the U. S. vice president under Theodore Roosevelt. Since its inception, Delta Sigma Phi has chartered chapters at 233 different colleges and universities, with 115 operating undergraduate chapters and colonies across the United States today; the fraternity has more than 8,000 undergraduate active members and more than 85,000 living alumni members. More than 150,000 men have been initiated into Delta Sigma Phi since its founding. At the end of the nineteenth century, most fraternities were Christian or Jewish, barred membership to individuals on the basis of religion.
When a group of friends at the City College of New York tried to join a fraternity, they were denied membership because their group was composed of Christians and Jews. In response, they organized the first Delta Sigma Phi chapter on Dec. 10, 1899. The chapter was called Insula due to its location in Manhattan. In late 1902, with five members from Insula signing incorporation papers, Delta Sigma Phi was incorporated with the purpose to spread "the principles of friendship and brotherhood among college men, without respect to race or creed." By 1903 the fraternity had established chapters at New York University. Delta Sigma Phi recognizes Charles A. Tonsor, Jr. and Meyer Boskey as its two primary founding fathers. Although Boskey was one of the original members at the City College of New York and Tonsor was one of the charter members of the chapter at New York University, it is believed the fraternity was developed by a group of nearly a dozen men. During the short period when men of Jewish faith were barred membership, many of the fraternity's founding documents were ruined.
Given the circumstances, the national organization adopted both Boskey and Tonsor as the "founders" given their lifelong commitment to the fraternity and their service as visionaries for the development of the fraternity's ritual and national expansion. In the two years after the 1914 Convention, Delta Sigma Phi doubled in size with the addition of 10 chapters. In 1915, the first West Coast chapter, Hilgard Chapter at UC Berkeley was installed. Hilgard Chapter was named after a dean at the university and is the fraternity's only chapter without a Greek letter designation, taking the place of Xi Chapter. In 1914, the fraternity decided to admit only white men of the Christian faith, thus rejecting the founders' vision. Many Jewish members and other minorities left Delta Sigma Phi or joined others, including Meyer Boskey, who withdrew active participation in the fraternity for an extended period of time; as a testament to the geographic shift of the fraternity, the 1916 convention was held in Chicago, Illinois.
By this time, Delta Sigma Phi had expanded the number of staff and a national headquarters was created at the Riebold Building at Dayton, Ohio. When the United States entered World War I in 1917 Delta Sigma Phi had more than 1,000 initiates and 19 active chapters. During the course of the war better than three-quarters of the fraternity's membership served the government in some capacity with half of that number in combat duty overseas. Publication of The Carnation, the fraternity's magazine, the 1917 and 1918 conventions were suspended for the duration of the war. Though the colleges and universities remained open during the war many chapters suspended their operations when most of their members were called to service; some chapters never recovered from the disruptions of World War I. Delta Sigma Phi went through continued expansion during the 1920s, at which time many local fraternities and other social clubs petitioned for fraternity membership. Among these was Phi Nu fraternity at McGill University in Montreal, Canada.
When Phi Nu was chartered as the Alpha Omicron Chapter, Delta Sigma Phi became an international fraternity. Two of these chapters, the Alpha Theta Chapter at The University of Michigan and the Alpha Chi Chapter at Stetson University, were local organizations older than Delta Sigma Phi itself, it was during this time Delta Sigma Phi published its first pledge manual, the Gordian Knot. It was based upon a manual published by the Epsilon Chapter at Penn State; the Gordian Knot is considered to be one of the first pledge manuals to be published on a fraternity-wide basis. Another tradition started at this time was the Sailors' Ball, first held at the Alpha Chi Chapter at Stetson University. Today, the Sailors' Ball is an annual event, a semi-formal counterpart to the Carnation Ball, the fraternity's formal banquet; the Alpha Eta Chapter at Ohio Northern University in Ada, Ohio was founded in 1920. Two months after the Wall Street Crash of 1929, Delta Sigma Phi's yearly convention was held in Richmond, Virginia.
Despite the financial uncertainties of the time, a traveling secretary was added to the fraternity payroll. During the Great Depression the national fraternity's growth had ground to a halt. Several chapters lost their equity in chapter properties. Among them were Gamma; the only chapters founded during the Great
Digital signal processing
Digital signal processing is the use of digital processing, such as by computers or more specialized digital signal processors, to perform a wide variety of signal processing operations. The signals processed in this manner are a sequence of numbers that represent samples of a continuous variable in a domain such as time, space, or frequency. Digital signal processing and analog signal processing are subfields of signal processing. DSP applications include audio and speech processing, sonar and other sensor array processing, spectral density estimation, statistical signal processing, digital image processing, signal processing for telecommunications, control systems, biomedical engineering, among others. DSP can involve linear or nonlinear operations. Nonlinear signal processing is related to nonlinear system identification and can be implemented in the time and spatio-temporal domains; the application of digital computation to signal processing allows for many advantages over analog processing in many applications, such as error detection and correction in transmission as well as data compression.
DSP is applicable to static data. To digitally analyze and manipulate an analog signal, it must be digitized with an analog-to-digital converter. Sampling is carried out in two stages and quantization. Discretization means that the signal is divided into equal intervals of time, each interval is represented by a single measurement of amplitude. Quantization means. Rounding real numbers to integers is an example; the Nyquist–Shannon sampling theorem states that a signal can be reconstructed from its samples if the sampling frequency is greater than twice the highest frequency component in the signal. In practice, the sampling frequency is significantly higher than twice the Nyquist frequency. Theoretical DSP analyses and derivations are performed on discrete-time signal models with no amplitude inaccuracies, "created" by the abstract process of sampling. Numerical methods require a quantized signal, such as those produced by an ADC; the processed result might be a set of statistics. But it is another quantized signal, converted back to analog form by a digital-to-analog converter.
In DSP, engineers study digital signals in one of the following domains: time domain, spatial domain, frequency domain, wavelet domains. They choose the domain in which to process a signal by making an informed assumption as to which domain best represents the essential characteristics of the signal and the processing to be applied to it. A sequence of samples from a measuring device produces a temporal or spatial domain representation, whereas a discrete Fourier transform produces the frequency domain representation; the most common processing approach in the time or space domain is enhancement of the input signal through a method called filtering. Digital filtering consists of some linear transformation of a number of surrounding samples around the current sample of the input or output signal. There are various ways to characterize filters. Linear filters satisfy the superposition principle, i.e. if an input is a weighted linear combination of different signals, the output is a weighted linear combination of the corresponding output signals.
A causal filter uses only previous samples of the output signals. A non-causal filter can be changed into a causal filter by adding a delay to it. A time-invariant filter has constant properties over time. A stable filter produces an output that converges to a constant value with time, or remains bounded within a finite interval. An unstable filter can produce an output that grows without bounds, with bounded or zero input. A finite impulse response filter uses only the input signals, while an infinite impulse response filter uses both the input signal and previous samples of the output signal. FIR filters are always stable. A filter can be represented by a block diagram, which can be used to derive a sample processing algorithm to implement the filter with hardware instructions. A filter may be described as a difference equation, a collection of zeros and poles or an impulse response or step response; the output of a linear digital filter to any given input may be calculated by convolving the input signal with the impulse response.
Signals are converted from time or space domain to the frequency domain through use of the Fourier transform. The Fourier transform converts the time or space information to a magnitude and phase component of each frequency. With some applications, how the phase varies with frequency can be a significant consideration. Where phase is unimportant the Fourier transform is converted to the power spectrum, the magnitude of each frequency component squared; the most common purpose for analysis of signals in the frequency domain is analysis of signal properties. The engineer can study the spectrum to determine which frequencies are present in the input signal and which are missing. Frequency domain analysis is called spectrum- or spectral analysis. Filtering in non-realtime work can be achieved in the frequency domain, applying the filter and converting back to the time domain; this can be an efficient implementation and can g
Devi Sri Prasad
Devi Sri Prasad is an Indian music composer, lyricist and director. He is best known for his works in the cinema of South India in Telugu cinema, he has won eight Filmfare Awards, seven of which are Filmfare Best Music Director South Awards and one Special Jury Award, five CineMAA Awards - Best Music Director, & one Nandi Award for Best Music Director. Devi choreographed a song in the Telugu film Kumari 21F
Desmoplakin is a protein in humans, encoded by the DSP gene. Desmoplakin is a critical component of desmosome structures in cardiac muscle and epidermal cells, which function to maintain the structural integrity at adjacent cell contacts. In cardiac muscle, desmoplakin is localized to intercalated discs which mechanically couple cardiac cells to function in a coordinated syncytial structure. Mutations in desmoplakin have been shown to play a role in dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, striate palmoplantar keratoderma, Carvajal syndrome and paraneoplastic pemphigus. Desmoplakin exists as two predominant isoforms; these isoforms are identical except for the shorter rod domain in DPII. DPI is the predominant isoform expressed in cardiac muscle; the DSP gene is located on chromosome 6p24.3, containing 24 exons and spanning 45 kDa of genomic DNA. Desmoplakin is a large desmosomal plaque protein that homodimerizes and adopts a dumbbell-shaped conformation; the N-terminal globular head domain of desmoplakin is composed of a series of alpha helical bundles, is required for both the localization to the desmosome and interaction with the N-terminal region of plakophilin 1 and plakoglobin as well as desmocollin and desmoglein.
This is further sub divided into a region called the "Plakin domain" made up of six spectrin repeat domains separated by SH3 domain. A crystal structure of part of the plakin domain has been resolved, while the entire plakin domain has been elucidated using small angle X-ray scattering which revealed a non-linear structure, an unexpected result considering spectrin repeats are observed in linear orientations; the C-terminal region of desmoplakin is composed of three plakin repeat domains, termed A, B and C, which are essential for coalignment and binding of intermediate filaments. Located at the most distal C-terminus of desmoplakin is a region rich in glycine–serine–arginine. In the mid-region of desmoplakin, a coiled-coil rod domain is responsible for homodimerization. Desmosomes are intercellular junctions that link adjacent cells. Desmoplakin is an obligate component of functional desmosomes that anchors intermediate filaments to desmosomal plaques. In cardiomyocytes, desmoplakin forms desmosomal plaques with the intermediate filament desmin, whereas in endothelial cells cytokeratin type intermediate filaments are recruited, vimentin in arachnoid and follicular dendritic cell types.
Both types of intermediate filaments attach in a lateral fashion to desmoplakin to form the plaque. In cardiac muscle, desmoplakin is localized to desmosomes in intercalated discs. Desmoplakin isoform DPI is expressed and is thought to play a role in both the assembly and stabilization of desmosomes. In mice overexpressing a C-terminal mutated desmoplakin protein, desmoplakin binding to desmin is disrupted in cardiac muscle and hearts display abnormal intercalated disc formation and structure. Much has been learned regarding desmoplakin function from mutations in patients with arrhythmogenic right ventricular cardiomyopathy, where mutations in specific binding domains alter desmoplakin binding to plakoglobin or desmin and result in cell death and dysfunction. Mutations in this gene are the cause of several cardiomyopathies, including dilated cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy. Mutations in DSP have been associated with striate palmoplantar keratoderma. Carvajal syndrome results from an autosomal recessive mutation of a frameshift in DSP that results in a combination of above conditions, including dilated cardiomyopathy and woolly hair.
Patients with Carvajal syndrome suffer from heart failure in teenage years. A case of compound heterozygosity for two DSP nonsense mutations resulting in lethal acantholytic epidermolysis bullosa has been reported. Autoantibodies to DSP are a hallmark of the autoimmune disease paraneoplastic pemphigus. Decreased desmoplakin expression has been found in patients with oropharyngeal cancer and breast cancer, which may alter cell-cell adhesion properties and propagate metastasis. Desmoplakin has been shown to interact with: List of target antigens in pemphigus List of conditions caused by problems with junctional proteins GeneReviews/NCBI/NIH/UW entry on Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy, Autosomal Dominant OMIM entries on Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy, Autosomal Dominant Desmoplakins at the US National Library of Medicine Medical Subject Headings
Delta Sigma Pi
Delta Sigma Pi is one of the largest co-ed professional business fraternities in the United States. Delta Sigma Pi was founded on November 7, 1907, at the School of Commerce and Finance of New York University in New York, New York and is headquartered in Oxford, Ohio; the Fraternity has 224 active collegiate chapters and 7 colonies, as well as 57 active alumni chapters, with over 280,000 initiated members. Delta Sigma Pi is a professional fraternity organized to foster the study of business in universities. Delta Sigma Pi was founded by four men: Alexander Frank Makay, Henry Albert Tienken, Harold Valentine Jacobs, Alfred Moysello; these four men, along with a fifth student, grew close to one another in their classes and from sharing the same subway route on their way home every evening. They discussed topics of mutual interest including school affairs. One such topic that came up involved the dominance of Alpha Kappa Psi, founded a few years earlier as the only fraternity at NYU's School of Commerce and Finance.
The men felt they had been ignored by the fraternity due to their race and religion, so they decided to develop a new organization to provide students with an alternative. They decided the new organization would be a club open to all students, but the idea did not take off with the student body. In 1907, the fifth student, Charlie Cashmore, dropped from the group when he was offered the opportunity to join the aforementioned organization; the four abandoned their plans for a club in favor of forming another Greek letter fraternity. In 1911, the fraternity published its first newsletter; the second chapter was founded at Northwestern School of Commerce. National meetings, called the Grand Chapter Congress, became a regular tradition and to this day the national fraternity meets every other year to conduct business and elect its national leaders. After rapid expansion in the early 1920s, the fraternity opened its national headquarters in Chicago, Illinois. In 1957, the central office moved to Ohio adjacent to the campus of Miami University.
The biggest change in the history of the Fraternity took place in 1975, as the Board of Directors mandated that chapters were allowed to initiate female business students, to conform with Title IX. The red rose was adopted as the official flower of Deltasig at the first Board of Directors Meeting in 1921, it was the gift given to the wives and courted women of Deltasig brothers. One of the founding fathers, Harold V. Jacobs, suggested a rose as the official fraternity flower because his wife loved roses and it was her first name. Five years in 1926, Jacobs suggested that the song sung at LEAD schools and Grand Chapter Congress events, "Rose of Deltasig," be adopted as the official song of the fraternity; the Central Office of Delta Sigma Pi, national administrative headquarters, was established in Chicago, Illinois, in 1924. In the fall of 1956, it moved to 330 South Campus Avenue in Ohio. In 1970, the original building nearly doubled in size with the addition of wings on either side of the building.
In 2010 extensive renovations, including a courtyard featuring engraved bricks, were completed to make the building more functional and accessible. The Executive Director has a full-time staff. Leadership and Excellence Academies for Deltasigs focus on the educational development of members of Delta Sigma Pi. LEAD academies are held at several locations around the United States each year. Examples of these academies includes LEAD Schools, Provincial Conferences, Volunteer Leadership Workshops, the LeaderShape Institute. Since its inception in 1907, Delta Sigma Pi has installed 298 chapters, of which 224 are active. In addition to these chapters, Delta Sigma Pi has active colonies at 7 universities. Delta Sigma Pi has 57 franchised Alumni Chapters on its roll for the 2018-2019 year in the United States, over 40 more locations worldwide have Brothers with an interest in starting a new Alumni Chapter