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Information and Emerging Technologies, 2007. ICIET 2007. International Conference on

Date 6-7 July 2007

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Displaying Results 1 - 25 of 42
  • Multiple Neural Networks over Clustered Data (MNCD) to Obtain Instantaneous Frequencies (IFs)

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2151 KB) |  | HTML iconHTML  

    In this paper we present advantage of training MNCD for obtaining time localized frequencies (also called IF), which is one useful concept for describing the changing spectral structure of a time-varying signal, arising so often in time frequency distribution (TFD) theory. It has been found that training does not give the same results every time; this is because the weights are initialized to random values and high validation error may end up training early. Moreover once a network is trained with selected input, its performance improves significantly as opposed to the one that does not receive selected input data for training. The performance of MNCD can be compared by computing the entropy, mean square error (MSE) and time consumed for convergence. View full abstract»

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  • Speaker Accent Classification System Using a Fuzzy Gaussian Classifier

    Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2657 KB) |  | HTML iconHTML  

    A speaker's accent is the most important factor affecting the performance of automatic speech recognition (ASR) systems. This is due to the fact that accents vary widely, even within the same country or community. The reason may be attributed to the fuzziness between the boundaries of phoneme classes, a result of differences in a speaker's vocal tract and accent. In this paper, a new method of accent classification is proposed that is based on fuzzy Gaussian mixture models (FGMMs). The proposed method first uses a fuzzy clustering to fuzzily partition the data. In this way, fuzzy memberships to the cluster centres are determined by minimizing the distance between the cluster centres and feature vectors. Afterwards, a GMM classifier is trained by using the fuzzy Gaussian parameters to classify the speaker's accent. The experimental results show that the proposed method outperforms the Gaussian Mixture models, Vector Quantization modeling method, Hidden Markov Model, and Radial Basis Neural Networks. View full abstract»

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  • Temporal Patterns Analysis in EEG Data using Sonification

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (5027 KB) |  | HTML iconHTML  

    Brain computer interfacing is a direct communication pathway between human and computer. The area is innovative and under active research as a subset of human computer interaction. Brain computer interfacing typically utilize electroencephalogram (EEG) data to apply machine learning and or computational intelligence techniques to trigger actions. Electroencephalogram data is a multivariate time series data whose visualization suffers from problems like cluster overlapping and high dimensionality. In this paper we present a natural alternative to visualization i.e. sonification. Thus combining the two novel area of research to explore and get better results over the conventional approaches. Sonification is the use of non-speech audio to convey information. We have presented a technique to sonify alpha, beta and gamma bands present in the Electroencephalogram data. Experiments have been performed on EEG data of a controlled subject and the results have been discussed at the end. View full abstract»

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  • A Family of Multimodulus Algorithms for Blind Equalization of Square-QAM Signal

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2014 KB) |  | HTML iconHTML  

    In this paper, a modified family of blind equalization algorithms is proposed for use in quadrature amplitude modulation (QAM) based digital communication systems. We have called this family: the generalized multimodulus algorithms: MMA(p, q). This family is derived by introducing two degrees of freedom in the conventional MM criterion. We have shown that one of the members of this family, MM(2, 1), (which, to the best of our knowledge, has never been discussed) exhibits the fastest convergence for 16-QAM signal. The dynamic convergence behavior of MM(2, 1) is analyzed and shown to be conforming with simulation results. View full abstract»

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  • Adaptive Wavelet Domain Audio Steganography with High Capacity and Low Error Rate

    Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3177 KB) |  | HTML iconHTML  

    Embedding a secret message into a cover media without attracting attention, which is known as steganography, is desirable in some security applications. One of the medias which can be used as a cover media is audio signal. In this paper we introduce an adaptive wavelet domain steganography with high capacity and low error rate. We use lifting scheme to create perfect reconstruction filter banks which are Int2Int and hide data in least significant bits (LSB) of details coefficient in an adaptive way to reduce the error rate. Our method have zero error rate for hiding capacity below 100 kilo bits-per-second (kbps) and 0.3% error for 200 kbps, in comparison to 0.9% error of normal wavelet domain LSB steganography. Signal to noise ratio (SNR) values and listening tests results show that the stegano audio is imperceptible from original audio even with hiding capacity up to 200 kbps. View full abstract»

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  • An Adaptive Method for Blind Carrier Phase Recovery in a QAM Receiver

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (470 KB) |  | HTML iconHTML  

    New multimodulus-based adaptive algorithms are being devised for blind phase recovery in QAM communication systems. Analysis of stationary points, sensitivity, steady-state misadjustment, convergence time and tracking ability are being provided. The proposed algorithm is compared with two existing adaptive algorithms and it is shown that the proposed algorithm can provide much better performance in terms of convergence time and steady-state jitter at the cost of complexity. View full abstract»

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  • Fast Convergent Multimodulus Algorithm for Blind Equalization of QAM Signals

    Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (316 KB) |  | HTML iconHTML  

    In this paper; the variant of the much celebrated multimodulus algorithm (MMA) is presented for the blind equalization of QAM signals to achieve better performance at high transmission rate. In this course, a new error function is proposed by introducing additional nulls in the existing MMA error function at specific locations which enables the new scheme to achieve low steady state mean squared error (MSE), reduced residual inter symbol interference (ISI) and faster convergence than those of existing MMA. The efficacy of the proposed scheme has been proved through simulation results for 16, 64 and 256-QAM signaling. View full abstract»

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  • Improving the Performance of QoS Models in MANETs through Interference Monitoring and Correction

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (5002 KB)  

    Mobile ad hoc networks (MANETs) have been proposed for a wide variety of applications, some of which require the support of real time and multimedia services. To do so, the network should be able to offer quality of service (QoS) appropriate for the latency and throughput bounds to meet appropriate real time constraints imposed by multimedia data. Due to the limited resources such as bandwidth in a wireless medium, flows need to be prioritised in order to guarantee QoS to the flows that need it. In this research, we propose a scheme to provide QoS guarantee to high priority flows in the presence of other high as well as low priority flows so that both type of flows achieve best possible throughput and end-to-end delays. Nodes independently monitor the level of interference by checking the rates of the highest priority flows and signal corrective mechanisms when these rates fall outside of specified thresholds. This research investigates using simulations the effects of a number of important parameters in MANETs, including node speed, pause time, interference, and the dynamic monitoring and correction on system performance in static and mobile scenarios. In this report we show that the dynamic monitoring and correction provides improved QoS than fixed monitoring and correction to both high priority and low priority flows in MANETs. View full abstract»

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  • Performance Evaluation of H.264 video transmission in CDMA2000 Network

    Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3320 KB) |  | HTML iconHTML  

    A phenomenal growth in the mobile communication sector and ever increasing demand for multimedia information has lead to video streaming over mobile network. Upcoming 3rd generation networks, like CDMA-2000, provide high speed for transmission, allowing users have more online services. When video is used in mobile networks, the most important requirements are related to low bit-rates, frame-rates and the screen size of mobile device, along with usual bandwidth, delay and jitter requirements, especially when considering background traffic. While in wired network the quality of service (QoS) is sustainable, in wireless network, however, the error prone nature restricts the QoS. In this paper we investigated and compared the performance of upcoming video codec, H.264 with MPEG-4, when used in video transmission in mobile networks using non-acknowledgment (NAK) based radio link protocol (RLP). The results showed that the H.264 codec produced the most satisfying video quality. View full abstract»

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  • Performance Evaluation of IEEE 802.15.4 Based IPMAC Network

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (4928 KB) |  | HTML iconHTML  

    Wireless adoption in industries is gaining momentum. With the recent development on the standardization front by virtue of IEEE 802.15.4 (Zigbee), the critical task of industrial process monitoring and control can be undertaken wirelessly. This switching over to wireless is, however, in the investigative stages with a few early adoptions in the industry. This work studies the performance of an IEEE 802.15.4 based IPMAC network using star topology in a simulated environment. Results so obtained have been analyzed. General recommendations have been made regarding issues pertaining to time criticality and packet loss. View full abstract»

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  • Random Key Encryption a New Cryptographic Scheme

    Page(s): 1 - 7
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1360 KB) |  | HTML iconHTML  

    Data security has become one of the major challenges in computing. Among them cryptography is one of the various methods in data security, although many algorithms of cryptography are in use since long but every algorithm has its own set of problems. Similarly all these algorithms have broken up by hackers. An algorithm which is safe with minimal problems is yet to be developed. For the development of such an algorithm one should understand the strengths and weaknesses of current algorithms. This paper discusses various problems of the existing cryptographic schemes and proposes a new scheme RKE. View full abstract»

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  • Trees and Butterflies Barriers in Distributed Simulation System: A Better Approach to Improve Latency and the Processor Idle Time

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (4223 KB) |  | HTML iconHTML  

    Global virtual time (GVT) is used in parallel discrete event simulations to reclaim memory, commit output, detect termination, and handle errors. Mattern 's [I] has proposed G VT approximation with distributed termination detection algorithm. This algorithm works fine and gives optimal performance in terms of accurate GVT computation at the expense of slower execution rate. This slower execution rate results a high GVT latency. Due to the high GVT latency, the processors involve in communication remain idle during that period of time. As a result, the overall throughput of a discrete event parallel simulation system degrades significantly. Thus, the high G VT latency prevents the widespread use of this algorithm in discrete event parallel simulation system. However, if we could improve the latency of GVT computation, most of the discrete event parallel simulation system would likely take advantage of this technique in terms of accurate G VT computation. In this paper, we examine the potential use of tress and butterflies barriers with the Mattern's GVT structure using a ring. Simulation results demonstrate that the use of tree barriers with the Mattern's GVT structure can significantly improve the latency time and thus increase the overall throughput of the parallel simulation system. The performance measure adopted in this paper is the achievable latency for a fixed number of processors and the number of message transmission during the G VT computation. View full abstract»

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  • Use of Self-Adaptive Methodology in Wireless Sensor Networks for Reducing Energy Consumption

    Page(s): 1 - 7
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (5669 KB) |  | HTML iconHTML  

    A sensor network is made up of numerous small independent sensor nodes with sensing, processing and communicating capabilities. The sensor nodes have limited battery and a minimal amount of on-board computing power. A self-adaptive methodology that utilizes the source and path redundancy techniques to efficiently reduce the required energy consumption is proposed. The proposed methodology presents a self-adaptive strategy to optimize the number of active sensor nodes and assign equal time slots to each sensor nodes for sensing and communication with the BS. The self-adaptive property enables the proposed methodology to perform a global search for optimizing the position of active sensor nodes with respect to the location of the base station (BS). The global search performed by the proposed methodology is carried out in a complete top down manner. The proposed self-adaptive methodology, therefore, not only reduces the energy consumption of wireless sensor nodes but also effectively maximizes the lifetime of active sensor nodes. Simulation results demonstrate that the proposed methodology significantly minimizes the energy consumption and consequently increases the life time of active sensor nodes. View full abstract»

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  • New SUB-SLM Method for PAPR Reduction in OFDM Signals

    Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (4557 KB) |  | HTML iconHTML  

    Selected mapping is an efficient algorithm for PAPR reduction in multicarrier systems. Two major issues in this technique are the side information and complexity of the implementation in terms of the number of IF FT blocks being used. Our proposed algorithm deals with the complexity issue. The new algorithm called sub-SLM algorithm divides the OFDM sequence into multiple equal length sequences then the SLM algorithm is applied on these individual partial sequences. Both the length of the new IFFT and the SLM is changed in the individual block which reduces the complexity. Simulation results show a reduction of almost 3 dB and reduction of complexity by a factor greater than two. The PAPR performance is slightly degraded as compared to the original SLM technique but the complexity is improved considerably. View full abstract»

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  • Performance of MC-CDMA with TCM over Wireless Fading Channels

    Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (5067 KB) |  | HTML iconHTML  

    In this paper we investigate the performance of a trellis code modulated MC-CDMA system as a function of the number of sub-carriers, bits per symbol, information rate and different flavors of TCM over wireless fading channels. Extensive simulations are performed where random data is sent over multi-path Rayleigh fading channels and performance is evaluated for both slow and fast fading channels. Specifically, two ray multi-path channel employing Jakes model is assumed. Meaningful bit error rate (BER) performance curves are generated for a number of scenarios and based upon these results, useful comparisons are extracted and design guidelines provided for the upcoming 4G communication systems. View full abstract»

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  • A Trust based Security Framework for Pure AODV Network

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (4474 KB) |  | HTML iconHTML  

    This paper presents a trust based security framework to identify malicious nodes in ad hoc on-demand distance vector (AODV) protocol. In this framework each node calculates trust level of its neighboring nodes for route selection. Trust calculation process involves opinions of other nodes about the node whose trust level is to be determined. If a neighboring node has a trust level lower than a predefined threshold value, it is identified as malicious and it is not considered for route selection. The proposed security framework does not use any key distribution process and no changes are made in control packets of AODV. Simulation results show that the proposed framework improves performance of AODV by identifying and removing malicious nodes. Performance of the framework has been evaluated for three different types of malicious attacks (impersonation attack, colluding nodes attack and black hole attack). View full abstract»

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  • Availability simulation of Switch over for FSO and MMW

    Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (110 KB) |  | HTML iconHTML  

    Free Space Optics (FSO) links get attraction due to high bandwidth and the flexibility of wireless communication links. However weather patterns like fog and heavy snow fall effect the availability of FSO. Microwave links operating at 40-43 GHz can be considered as back up link due to similar properties regarding offered data rates and flexibility of set up. However rain limits microwave link availability. Redundant use of these links has proved as highly available high bandwidth wireless connection. But it needs redundant transmission on back up link of microwave even when FSO link is available. In this paper a switch over between these links has been proposed. Its performance has been simulated for one year measured availability data for these links. View full abstract»

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  • Further Cryptanalysis of 'A User Friendly Remote User Authentication Scheme with Smart Cards'

    Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1332 KB) |  | HTML iconHTML  

    Recently, Wu and Chieu proposed 'a user friendly remote user authentication scheme with smart cards'. We point out that their scheme is vulnerable and susceptible to the attacks and can easily be cryptanalyzed. Their scheme provides only unilateral authentication (only client authentication) and there is no mutual authentication between user and remote system, so their scheme suscepts from the server spoofing attack. Their scheme also suffers from the impersonation attack and an adversary can easily impersonate a valid user. Furthermore, we describe that an adversary can login into the system by copying the data of stolen or lost smart card of a legitimate user. Moreover, we discuss that Wu and Chieu's scheme has poor reparability, which makes it infeasible to implement. View full abstract»

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  • CFiTT - corrupt free file transfer technique

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2533 KB) |  | HTML iconHTML  

    Communication is one of the basic necessities of human beings. File transfer is one of the basic forms of communication. Reliability is the key issue raised due to complex nature of network and growth of computer science. In this paper we have devised a technique for file transfer which identifies whether some portion of the file is received corrupt or not, and if yes then exactly what portion is corrupt. This technique provides reliability by eliminating the corruption from a file, hence requiring less bandwidth of the network by reducing the amount of data to be re-sent in case of corruption. The reliability is ensured with the help of file signature generation method which we have devised in this paper. The beauty of this technique that it generates hashes which are not easy to break, hence ensuring security of the file. We have used TCP as the underlying protocol, whereas TCP is already considered to be reliable, but the fact is that it does not ensure the reliable transfer over the network due to the fact that it uses CRC which is still vulnerable to network conditions and malicious attacks. Our technique operates at the application layer and tries to finish the cope up with the reliability over the file transfer. We have also developed a prototype to test the integrity of our technique. Empirical results ensure the reliability of our technique. The emphasis of this paper is to provide users with the corrupt free file transfer over the network, so that their time and valuable resources might be saved. View full abstract»

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  • Digital Attendance Recording System

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3889 KB) |  | HTML iconHTML  

    Attendance recording in educational institutions is an imperative task. Most present systems provide database management but still involve laborious manual data entry procedures. The design presented in this paper offers a twofold solution to the problem. It relieves from handling paper records of attendance taken in the class by providing firsthand entry into a portable gadget built around the AVR ATmega8 microcontroller. The attendance entered is firstly stored in the microcontroller's EEPROMfrom where it is transferred to an application software residing on a computer through the serial port. This application stores the attendance data in a database and also displays requested information extracted from them. View full abstract»

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  • Enhancing Invisibility and Robustness of DWT based Video Watermarking scheme for Copyright Protection

    Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3574 KB) |  | HTML iconHTML  

    Requirements for digital watermarking are mainly application dependent. Robustness is one of the main requirements for many watermarking applications. In this paper a blind discrete wavelet transform (DWT) based video watermarking algorithm for copyright protection is proposed. We have embedded a meaningful watermark invisibly into uncompressed video. The watermark is embedded in high frequency sub-band coefficients of the DWT to improve the invisibility of the marked video sequence. The watermark is first scrambled and then encoded to minimize the error probabilities during watermark detection. We have applied 2-D automorphic transform and BCH error correction coding on the binary image for scrambling and encoding the watermark respectively before the watermark embedding. We have applied key based pseudo random 3-D interleaving on the coefficients selected for watermark insertion. We have also embedded the frame number as the synchronization information instead of using the sliding correlation as proposed in [1, 5]. Experimental results have proved that the embedded data with the proposed scheme is visually transparent, robust against unintentional or malicious attacks such as frames deleting, frames inserting and frame statistical averaging. 3-D interleaving has significantly improved the robustness of the proposed scheme against temporal attacks. The watermark embedded in such way is high bit rate and thus more robust. The series of experiments conducted has revealed the effectiveness and usefulness of the proposed watermark generation and embedding strategy. View full abstract»

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  • Hybrid Feature Selection Approach for Natural Language Call Routing Systems

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3906 KB) |  | HTML iconHTML  

    Call routing based on natural language identification is an important issue for call centres operating in a multilingual scenario. This is due to the fact that it is not possible for a human agent to become fluent in all languages. In this paper, we propose a call routing system based on prosodic and phonetic features to improve the performance of automatic call routing systems. The main focus of this paper is to propose a feature set that efficiently improves the performance of the system without incorporating several sets of features. Our proposed approach for combining the prosodic and phonetic features achieves an accuracy rate of 98.36% for a binary language identification call routing system. View full abstract»

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  • Paired Spectral Content Measure for Gene and Exon Prediction in Eukaryotes

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (520 KB) |  | HTML iconHTML  

    In this paper, we report on a new discrete Fourier transform (DFT) based method for gene and exon prediction in eukaryotes. The proposed paired spectral content (PSC) measure is compared with the well-known DFT based spectral content and spectral rotation measures, using the GENSCAN test set. False positive vs. sensitivity, receiver operating characteristic (ROC) curve and exonic nucleotides detected as false positive results all show that the newly proposed PSC outperforms existing methods, with 50% less DFT processing. View full abstract»

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  • Implementation of advanced radar processes on TMS320C5x processors

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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3689 KB) |  | HTML iconHTML  

    With respect to the advent of radar systems technology, necessity of using advanced and complex processing in the receivers, transfer of high volume of data and need of real time processing in relation to radar signals, appropriate processor must provide the required processing speed. This performance usually is provided with programmable digital signal processors. In this paper, first, processes such as pulse compression with phase coding method, clutter canceling with delay line canceller and Doppler filter bank methods are introduced, then several procedures of parametric and clutter map constant false alarm ratio along with combination of these two methods are described and finally possibility of implementation of these processes on a Texas Instrument DSP are investigated. View full abstract»

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  • A New Solution for Password Key Transferring in Steganography Methods by CAPTCHA through MMS Technology

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3648 KB) |  | HTML iconHTML  

    The Multimedia Messaging System (MMS) allows a user of a mobile phone to send messages containing multimedia objects, such as images, audio or video clips. On the other hand establishing hidden communication is an important subject of discussion that has gained increasing importance nowadays with the development of the Internet. One of the methods introduced for establishing hidden communication is steganography. Therefore steganography in MMS is an interesting idea. One of the problems in steganography methods is the security of transferring password key used for steganography between sender and receiver of secure data. In this paper a new method is proposed for solving this problem using CAPTCHA method through MMS messages. In this method the password key is spoken in an audio file and the data are hidden in the image by this password key. Then the image and audio files are inserted in a MMS message and sent to the receiver. Therefore the human receiver can recognize the password from the audio file and extract the data from the image using this password, but the computer cannot recognize the spoken word from the audio file and extracting the password. By this method the user does not need to memorize any password for extracting the data. This method has been implemented in J2ME programming language. View full abstract»

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